Jump Rope Training: Balance and Motor Coordination in Preadolescent Soccer Players.

PubMed

Trecroci, Athos; Cavaggioni, Luca; Caccia, Riccardo; Alberti, Giampietro

2015-12-01

General physical practice and multidimensional exercises are essential elements that allow young athletes to enhance their coordinative traits, balance, and strength and power levels, which are linked to the learning soccer-specific skills. Jumping rope is a widely-used and non-specific practical method for the development of athletic conditioning, balance and coordination in several disciplines. Thus, the aim of this study was to investigate the effects of a short-term training protocol including jumping rope (JR) exercises on motor abilities and body balance in young soccer players. Twenty-four preadolescent soccer players were recruited and placed in two different groups. In the Experimental group (EG), children performed JR training at the beginning of the training session. The control group (CG), executed soccer specific drills. Harre circuit test (HCT) and Lower Quarter Y balance test (YBT-LQ) were selected to evaluate participant's motor ability (e.g. ability to perform rapidly a course with different physical tasks such as somersault and passages above/below obstacles ) and to assess unilateral dynamic lower limb balance after 8 weeks of training. Statistical analysis consisted of paired t-test and mixed analysis of variance scores to determine any significant interactions. Children who performed jumping rope exercises showed a significant decrease of 9% (p < 0.01, ES = 0.50-0.80) in the performance time of HCT. With regard to the CG, no differences were highlighted (p > 0.05, ES = 0.05-0.2) from pre- to post-training. A training-by-group interaction was found for the composite score in both legs (p < 0.05, Part η(2) > 0.14). Our findings demonstrated that JR practice within regular soccer training enhanced general motor coordination and balance in preadolescent soccer players. Therefore, the inclusion of JR practice within regular soccer training session should encouraged to improve children's motor skills. Key pointsPerforming jumping rope exercises within a regular soccer program can be an additional method to improve balance and motor coordination.The performance improvement in the Harre Circuit Test associated with jump rope training can potentially be attributed to an enhancement of the inter-limb coordination and SSC ability.Results from the present study indicate that young soccer players should be encouraged to practice general physical activities together with sport-specific exercise during their training sessions.

Feasibility of Using Soccer and Job Training to Prevent Drug Abuse and HIV

PubMed Central

Rotheram-Borus, Mary Jane; Tomlinson, Mark; Durkin, Andrew; Baird, Kelly; DeCelles, Jeff; Swendeman, Dallas

2016-01-01

Background Many young, South African men use alcohol and drugs and have multiple partners, but avoid health care settings – the primary site for delivery of HIV intervention activities. Objectives To identify the feasibility of engaging men in HIV testing and reducing substance use with soccer and vocational training programs. Methods In two Cape Town neighborhoods, all unemployed men aged 18–25 years were recruited and randomized by neighborhood to: 1) an immediate intervention condition with access to a soccer program, random rapid diagnostic tests (RDT) for alcohol and drug use, and an opportunity to enter a vocational training program (n=72); or 2) a delayed control condition (n=70). Young men were assessed at baseline and six months later by an independent team. Results Almost all young men in the two neighborhoods participated (98%); 85% attended at least one practice (M = 42.3, SD= 34.4); 71% typically attended practice. Access to job training was provided to the 35 young men with the most on-time arrivals at practice, drug-free RDT, and no red cards for violence. The percentage of young men agreeing to complete RDT at soccer increased significantly over time; RDTs with evidence of alcohol and drug use decreased over time. At the pre-post assessments, the frequency of substance use decreased; and employment and income increased in the immediate condition compared to the delayed condition. HIV testing rates, health care contacts, sexual behaviors, HIV knowledge, condom use and attitudes towards women were similar over time. Discussion Alternative engagement strategies are critical pathways to prevent HIV among young men. This feasibility study shows that soccer and job training offer such an alternative, and suggest that a more robust evaluation of this intervention strategy be pursued. PMID:26837624

Feasibility of Using Soccer and Job Training to Prevent Drug Abuse and HIV.

PubMed

Rotheram-Borus, Mary Jane; Tomlinson, Mark; Durkin, Andrew; Baird, Kelly; DeCelles, Jeff; Swendeman, Dallas

2016-09-01

Many young, South African men use alcohol and drugs and have multiple partners, but avoid health care settings-the primary site for delivery of HIV intervention activities. To identify the feasibility of engaging men in HIV testing and reducing substance use with soccer and vocational training programs. In two Cape Town neighborhoods, all unemployed men aged 18-25 years were recruited and randomized by neighborhood to: (1) an immediate intervention condition with access to a soccer program, random rapid diagnostic tests (RDT) for alcohol and drug use, and an opportunity to enter a vocational training program (n = 72); or (2) a delayed control condition (n = 70). Young men were assessed at baseline and 6 months later by an independent team. Almost all young men in the two neighborhoods participated (98 %); 85 % attended at least one practice (M = 42.3, SD = 34.4); 71 % typically attended practice. Access to job training was provided to the 35 young men with the most on-time arrivals at practice, drug-free RDT, and no red cards for violence. The percentage of young men agreeing to complete RDT at soccer increased significantly over time; RDTs with evidence of alcohol and drug use decreased over time. At the pre-post assessments, the frequency of substance use decreased; and employment and income increased in the immediate condition compared to the delayed condition. HIV testing rates, health care contacts, sexual behaviors, HIV knowledge, condom use and attitudes towards women were similar over time. Alternative engagement strategies are critical pathways to prevent HIV among young men. This feasibility study shows that soccer and job training offer such an alternative, and suggest that a more robust evaluation of this intervention strategy be pursued.

[RATE OF PHYSICAL DEVELOPMENT IN BOYS AGED 10-11 YEARS AND THE EFFECTS OF TRAINING LOADS DURING A 12-MONTH SOCCER PROGRAM].

PubMed

Boraczyński, Michał; Sozański, Henryk

2015-01-01

The aim of the study was to evaluate the rate of physical development in prepubertal boys in response to training at different loads. The study involved two groups of soccer players, experimental groups E1 (n = 26, age 10.4 ± 0.6 years) and E2 (n = 27, age 10.3 ± 0.8 years) who were involved in a 12-month soccer training program, and a control group (C) of age-matched untrained boys (n = 22). The training protocol of E1 involved a greater share of coordination-based exercises, in E2 more focus was placed on conditioning fitness and strength. Body height, mass, fat percentage, and body mass index were measured pre-, peri-, and post-training. Chronological and developmental age were used to calculate a Biological State Maturity Index (BSMI). Between-group differences were observed in body fat percentage, which was higher in the control group by 6.8% at post-training compared with E1 (p < 0.05). E1 showed the most congruence between chronological and developmental age. Developmental age was most retarded in E2 by an average of 4.3 months. Greatest between-group differences were observed in E1 and the control group for the BSMI of body height (49.9%) at pre-training. BSMI of height and mass in the control group were different (p < 0.01) from both experimental groups at pre-, peri-, and post-training. 1. The experimental soccer training programs were conducive to the physical development of boys aged 10-11 years as evidenced by the absence of disturbances in the range of observed variables characterizing the body built and biological development. 2. Body mass index did not accurately reflect changes in body composition. A more detailed analysis of body composition is required in the recruitment and selection of young soccer players in order to better control the effects of training and diet. 3. The adopted BSMI measure indicated a delay in growth according to developmental age norms in the entire sample. However, the accelerated physical development in E1 during the study duration may be indicative of the stimulative effect of this group's training program and the adopted training load on physical development.

The effect of plyometric training on power and kicking distance in female adolescent soccer players.

PubMed

Rubley, Mack D; Haase, Amaris C; Holcomb, William R; Girouard, Tedd J; Tandy, Richard D

2011-01-01

The purpose of this study was to measure the effects of low-frequency, low-impact plyometric training on vertical jump (VJ) and kicking distance in female adolescent soccer players. Sixteen adolescent soccer players were studied (age 13.4 ± 0.5 years) across 14 weeks. The control group (general soccer training only) had 6 subjects, and the plyometric training (general soccer training plus plyometric exercise) group had 10 subjects. All subjects were tested for VJ and kicking distance on 3 occasions: pre-test, 7 weeks, and 14 weeks. Data were analyzed using a 2 (Training) × 3 (Test) analysis of variance (ANOVA) with repeated measures on the factor test. No significant difference in kicking distance was found between groups at pre-test (p = 0.688) or 7 weeks (p = 0.117). The plyometric group had significantly greater kicking distance after 14 weeks (p < 0.001). No significant difference in VJ height was found between groups at pre-test (p = 0.837) or 7 weeks (p = 0.108). The plyometric group had a significantly higher VJ after 14 weeks (p = 0.014). These results provide strength coaches with a safe and effective alternative to high-intensity plyometric training. Based on these findings, to increase lower-body power resulting in increased VJ and kicking distance, strength coaches should implement once-weekly, low-impact plyometric training programs with their adolescent athletes.

Sequencing Effects of Plyometric Training Applied Before or After Regular Soccer Training on Measures of Physical Fitness in Young Players.

PubMed

Ramirez-Campillo, Rodrigo; Alvarez, Cristian; Gentil, Paulo; Loturco, Irineu; Sanchez-Sanchez, Javier; Izquierdo, Mikel; Moran, Jason; Nakamura, Fabio Y; Chaabene, Helmi; Granacher, Urs

2018-03-22

To compare the effects of short-term (i.e., 7 week) plyometric training applied before (PJT-B) or after (PJT-A) soccer practice on components of physical fitness in young soccer players, a single-blind randomized controlled trial was conducted. Post-pubertal boys aged 17.0±0.5 years were allocated to three groups: PJT-B (n=12), PJT-A (n=14), and control (CON; n=12). The outcome measures included tests to evaluate 20-m speed, standing long jump [SLJ], squat jump [SJ], countermovement jump [CMJ], and drop jump [DJ], 20-m multistage shuttle running speed [MSSRT], and Illinois change of direction speed [ICODT]. While the CON performed soccer-specific training, the PJT-A and PJT-B groups conducted the same soccer-specific sessions but replaced ∼11% of their time with plyometric training. The PJT-B group performed plyometric exercises after a warm-up program, and the PJT-A group conducted plyometric exercises ∼10 minutes after the completion of soccer training. Analyses of variance (ANOVAs) were used to detect differences between groups in all variables for pre- and post-training tests. Main effects of time (all p<.01; d=0.19-0.79) and group x time interactions (all p<.05; d=0.17-0.76) were observed for all examined variables. Post hoc analyses revealed significant increases in the PJT-B group (SLJ: 9.4%, d=1.7; CMJ: 11.2%, d=0.75; 20-m MSSRT: 9.0%, d=0.77) and the PJT-A group (SLJ: 3.1%, d=0.7; CMJ: 4.9%, d=0.27; 20-m MSSRT: 9.0%, d=0.76). Post hoc analyses also revealed significant increases in the PJT-B group (20-m speed: -7.4%, d=0.75; 20-cm DJ reactive strength index: 19.1%, d=1.4; SJ: 6.3%, d=0.44; ICODT results: -4.2%, d=1.1). In general, our study revealed that plyometric training is effective in improving measures of physical fitness in young male soccer players when combined with regular soccer training. More specifically, larger training induced effects on physical fitness were registered if plyometric training was conducted prior to soccer specific training.

Effect of Exercise Program Speed, Agility, and Quickness (SAQ) in Improving Speed, Agility, and Acceleration

NASA Astrophysics Data System (ADS)

Azmi, K.; Kusnanik, N. W.

2018-01-01

This study aimed to analyze the effect of speed, agility and quickness training program to increase in speed, agility and acceleration. This study was conducted at 26 soccer players and divided into 2 groups with 13 players each group. Group 1 was given SAQ training program, and Group 2 conventional training program for 8 weeks. This study used a quantitative approach with quasi-experimental method. The design of this study used a matching-only design. Data was collected by testing 30-meter sprint (speed), agility t-test (agility), and run 10 meters (acceleration) during the pretest and posttest. Furthermore, the data was analyzed using paired sample t-test and independent t-test. The results showed: that there was a significant effect of speed, agility and quickness training program in improving in speed, agility and acceleration. In summary, it can be concluded that the speed, agility and quickness training program can improve the speed, agility and acceleration of the soccer players.

Effect of Training on Physiological and Biochemical Variables of Soccer Players of Different Age Groups

PubMed Central

Manna, Indranil; Khanna, Gulshan Lal; Chandra Dhara, Prakash

2010-01-01

Purpose To find out the effect of training on selected physiological and biochemical variables of Indian soccer players of different age groups. Methods A total of 120 soccer players volunteered for the study, were divided (n = 30) into 4 groups: (i) under 16 years (U16), (ii) under 19 years (U19), (iii) under 23 years (U23), (iv) senior (SR). The training sessions were divided into 2 phases (a) Preparatory Phase (PP, 8 weeks) and (b) Competitive Phase (CP, 4 weeks). The training program consisted of aerobic, anaerobic and skill development, and were completed 4 hrs/day; 5 days/week. Selected physiological and biochemical variables were measured at zero level (baseline data, BD) and at the end of PP and CP. Results A significant increase (P < 0.05) in lean body mass (LBM), VO2max, anaerobic power, grip and back strength, urea, uric acid and high density lipoprotein cholesterol (HDL-C); and a significant decrease (P < 0.05) in body fat, hemoglobin (Hb), total cholesterol (TC), triglyceride (TG) and low density lipoprotein cholesterol (LDL-C) were detected in some groups in PP and CP phases of the training when compare to BD. However, no significant change was found in body mass and maximal heart rate of the players after the training program. Conclusion This study would provide useful information for training and selection of soccer players of different age groups. PMID:22375187

Effects of a combined resistance-plyometric training program on muscular strength, running economy, and Vo2peak in division I female soccer players.

PubMed

Grieco, Carmine R; Cortes, Nelson; Greska, Eric K; Lucci, Shawn; Onate, James A

2012-09-01

Resistance and plyometric training programs have demonstrated consistent improvements in running economy (RE) in trained and untrained adults in the absence of improvements in maximal oxygen consumption. The purpose of this study was to investigate the effect of a 10-week combined resistance-plyometric training program on the RE and V[Combining Dot Above]O2max in female soccer players. Fifteen Division 1A female soccer players (age 19.0 ± 0.7 years; height 1.67 ± 0.1 m; weight 61.7 ± 8.1 kg) performed a treadmill test for V[Combining Dot Above]O2max and RE at the end of a competitive season (PRE) and after a 10-week training program (POST). Isometric strength was measured in knee flexion and extension. Resistance training was conducted 2 d·wk on nonconsecutive days; plyometric training was conducted separately on different nonconsecutive days. Eleven subjects were included in the PRE-POST analysis (age 19.0 ± 0.8 years; height 1.67 ± 0.5 m; weight 59.9 ± 6.7 kg). Descriptive statistics were compared using analysis of variance with repeated measures with a Bonferroni adjustment, and significance was set at p < 0.05. A significant increase occurred after training in the V[Combining Dot Above]O2peak (10.5%; p = 0.008), time to fatigue (6.9%; p = 0.017), and interpolated maximal speed (3.6%; p = 0.016), despite there being a decrease in the maximal respiratory exchange ratio (2.9%; p = 0.001). There was no significant change in the RE at 9 km·h; however, there was a significant decrease in the percentage of the V[Combining Dot Above]O2peak at 9 km·h (-5.6%; p = 0.02). Maximal isometric strength of knee flexors and extensors did not change. The results suggest a plyometric-agility training program may increase the V[Combining Dot Above]O2peak in female soccer players; however, the effect on RE was equivocal.

Jump Training in Youth Soccer Players: Effects of Haltere Type Handheld Loading.

PubMed

Rosas, F; Ramirez-Campillo, R; Diaz, D; Abad-Colil, F; Martinez-Salazar, C; Caniuqueo, A; Cañas-Jamet, R; Loturco, I; Nakamura, F Y; McKenzie, C; Gonzalez-Rivera, J; Sanchez-Sanchez, J; Izquierdo, M

2016-12-01

The aim of this study was to compare the effects of a jump training program, with or without haltere type handheld loading, on maximal intensity exercise performance. Youth soccer players (12.1±2.2 y) were assigned to either a jump training group (JG, n=21), a jump training group plus haltere type handheld loading (LJG, n=21), or a control group following only soccer training (CG, n=21). Athletes were evaluated for maximal-intensity performance measures before and after 6 weeks of training, during an in-season training period. The CG achieved a significant change in maximal kicking velocity only (ES=0.11-0.20). Both jump training groups improved in right leg (ES=0.28-0.45) and left leg horizontal countermovement jump with arms (ES=0.32-0.47), horizontal countermovement jump with arms (ES=0.28-0.37), vertical countermovement jump with arms (ES=0.26), 20-cm drop jump reactive strength index (ES=0.20-0.37), and maximal kicking velocity (ES=0.27-0.34). Nevertheless, compared to the CG, only the LJG exhibited greater improvements in all performance tests. Therefore, haltere type handheld loading further enhances performance adaptations during jump training in youth soccer players. © Georg Thieme Verlag KG Stuttgart · New York.

[Effect of Core Muscle Strengthening Exercises (Including Plank and Side Plank) on Injury Rate in Male Adult Soccer Players: A Systematic Review].

PubMed

Blasimann, Angela; Eberle, Simon; Scuderi, Manuel Markus

2018-03-01

 Soccer is seen as highly intensive sport with an increased injury rate. Male adults are the players with the highest injury incidence. Accordingly, the importance of core muscle strengthening to prevent injury has increased in the past few years. Up to date, core muscle strengthening plays an important role in different prevention programs, such as the "FIFA 11 +". The aim of this systematic review was to investigate the effect of core muscle strengthening on injury rate in male adult soccer players, including at least the known and easy exercises "plank" and "side plank", on injury rate in male adult soccer players.  The databases PubMed, PEDro, Cochrane Library, SPORTDiscus and Cinahl were searched systematically. Included studies had to comprise exercises for core muscles as an intervention (as a part of a prevention program) for adult male soccer players. The control group had to continue their usual exercise routine. The exercises "plank" and "side plank" were mandatory elements of the training program. The number of injuries and/or the injury rate (per 1000 hours) were defined as outcomes. The quality of the included studies was assessed with the PEDro scale and the Risk of Bias tool.  Seven studies with 2491 participants in total could be included. Two studies found a significant decrease in the injury rate in the intervention group (p < 0.05, p < 0.001 respectively). In two studies, no significance level was reported, but the training showed preventive effects in the intervention group. In the other three studies, no significant changes in the injury rate were found (p > 0.05).  The seven included studies differed greatly with respect to the applied methods, the chosen interventions and the obtained results. Furthermore, core muscles were never trained separately but were always part of a program containing other preventive elements. Therefore, it was difficult to compare the studies. However, prevention programs including strengthening exercises for core muscles tend to positively affect the injury rate. Based on the literature found, the research question cannot definitively be answered. In the future, further studies are needed which investigate the effect of isolated core muscle training on the injury rate of soccer players. © Georg Thieme Verlag KG Stuttgart · New York.

Soccer Injuries in Players Aged 7 to 12 Years: A Descriptive Epidemiological Study Over 2 Seasons.

PubMed

Rössler, Roland; Junge, Astrid; Chomiak, Jiri; Dvorak, Jiri; Faude, Oliver

2016-02-01

As part of a risk-management approach, sound epidemiological data are needed to develop prevention programs. A recent review on soccer injuries of players younger than 19 years concluded that prospective data concerning children are lacking. To analyze the incidence and characteristics of soccer injuries in children aged 7 to 12 years. Descriptive epidemiological study. The present survey was a prospective descriptive epidemiological study on soccer injuries over 2 seasons in the Czech Republic and Switzerland. Exposure of players during training and match play (in hours) and injury data were reported by coaches via an Internet-based registration system. Location, type, and severity of injuries were classified according to an established consensus. Injury characteristics are presented as absolute numbers and injury incidence rates (injuries per 1000 hours of soccer exposure). An injury was defined as any physical complaint sustained during a scheduled training session or match play resulting in at least 1 of the following: (1) inability to complete the current match or training session, (2) absence from subsequent training sessions or matches, and (3) injury requiring medical attention. In total, 6038 player-seasons with 395,295 hours of soccer exposure were recorded. The mean (±SD) age of the players was 9.5 ± 2.0 years, and 3.9% of the participants were girls. A total of 417 injuries were reported. Most (76.3%) injuries were located in the lower limbs, with 15.6% located in the upper limbs. Joint and ligament injuries comprised 30.5%, contusions 22.5%, muscle and tendon injuries 18.5%, and fractures and bone injuries 15.4% of all injuries; 23.7% of injuries led to more than 28 days of absence from sport participation. The overall injury incidence was 0.61 (95% CI, 0.53-0.69) injuries per 1000 hours of soccer exposure during training sessions and 4.57 (95% CI, 4.00-5.23) during match play. Injury incidence rates increased with increasing age. The observed injury incidences were lower compared with studies in youth players. Children showed a relatively high proportion of fractures and bone stress and of injuries to the upper limbs. The study provides an evidence base for injury incidence rates and injury characteristics in children's soccer. These data are the basis to develop an age-specific injury-prevention program. © 2015 The Author(s).

Moderate running and plyometric training during off-season did not show a significant difference on soccer-related high-intensity performances compared with no-training controls.

PubMed

Nakamura, Daisuke; Suzuki, Tomohiro; Yasumatsu, Mikinobu; Akimoto, Takayuki

2012-12-01

Several investigators have reported the effects of reduced training and interrupted training on athletic performance, but few reports are available for soccer players. The purpose of this study was to examine, using the Yo-Yo intermittent recovery level 2 (YoYoIR2) test and sprint performance, the effects on soccer players of a reduced training program consisting of either moderate running training, plyometric training. After the completion of a competitive season, 29 male soccer players were divided into 3 groups: the running group (n = 13), the plyometric group (n = 11), and the control group (n = 5). Both training groups completed either running or plyometric training sessions 2 d·wk(-1) for 3 weeks, whereas the control group was not allowed to perform any training. The subjects performed YoYoIR2 and 20-m sprint tests before (pre) and after (post) the experimental period. Neither training group showed any significant training effects on the YoYoIR2 performance or 20-m sprint times compared with the control group. This study suggests that neither endurance running nor plyometric training 2 d·wk(-1) for 3 weeks has a significant effect on high-intensity performance compared with a nontraining regimen. However, our results do not support complete inactivity. These results may have important implications for the management of training cessation for a few weeks.

Do cognitive training strategies improve motor and positive psychological skills development in soccer players? Insights from a systematic review.

PubMed

Slimani, Maamer; Bragazzi, Nicola Luigi; Tod, David; Dellal, Alexandre; Hue, Olivier; Cheour, Foued; Taylor, Lee; Chamari, Karim

2016-12-01

Soccer players are required to have well-developed physical, technical and cognitive abilities. The present systematic review, adhering to Preferred Reporting Items for Systematic reviews and Meta-Analysis guidelines, examined the effects of cognitive training strategies on motor and positive psychological skills development in soccer performance and identified the potential moderators of the "cognitive training-soccer performance" relationship. Thirteen databases were systematically searched using keywords related to psychological or cognitive training in soccer players. The review is based on 18 studies, employing 584 soccer players aged 7-39 years. Cognitive strategies, particularly imagery, appear to improve sports performance in soccer players. Regarding imagery, the combination of two different types of cognitive imagery training (i.e., cognitive general and cognitive specific) has a positive influence on soccer performance during training, whereas motivational imagery (i.e., motivational general-arousal, motivational general-mastery and motivational specific) enhance competition performance. Younger soccer players employ cognitive general and cognitive specific imagery techniques to a greater extent than older soccer players. Combined cognitive training strategies were more beneficial than a single cognitive strategy relative to motor skills enhancement in elite (particularly midfielders) and amateur (i.e., when practising complex and specific soccer skills in precompetitive period) soccer players. In conclusion, it appears that there are differences in cognitive/psychological training interventions, and their efficacy, according to whether they are directed towards training or competition, and the age, standard and playing position of the players.

The effects of maturation on jumping ability and sprint adaptations to plyometric training in youth soccer players.

PubMed

Asadi, Abbas; Ramirez-Campillo, Rodrigo; Arazi, Hamid; Sáez de Villarreal, Eduardo

2018-04-03

The aim of this study was to investigate the effects of maturation on power and sprint performance adaptations following 6 weeks of plyometric training in youth soccer players during pre-season. Sixty male soccer players were categorized into 3 maturity groups (Pre, Mid and Post peak height velocity [PHV]) and then randomly assigned to plyometric group and control group. Vertical jump, standing long jump, and 20-m sprint (with and without ball) tests were collected before- and after-intervention. After the intervention, the Pre, Mid and Post-PHV groups showed significant (P ≤ 0.05) and small to moderate effect size (ES) improvement in vertical jump (ES = 0.48; 0.57; 0.73), peak power output (E = 0.60; 0.64; 0.76), standing long jump (ES = 0.62; 0.65; 0.7), 20-m sprint (ES = -0.58; -0.66), and 20-m sprint with ball (ES = -0.44; -0.8; -0.55) performances. The Post-PHV soccer players indicated greater gains than Pre-PHV in vertical jump and sprint performance after training (P ≤ 0.05). Short-term plyometric training had positive effects on sprinting and jumping-power which are important determinants of match-winning actions in soccer. These results indicate that a sixty foot contact, twice per week program, seems effective in improving power and sprint performance in youth soccer players.

Effects of an In-season Plyometric Training Program on Repeated Change of Direction and Sprint Performance in the Junior Soccer Player.

PubMed

Hammami, Mehréz; Negra, Yassine; Aouadi, Ridha; Shephard, Roy J; Chelly, Mohamed Souhaiel

2016-12-01

Hammami, M, Negra, Y, Aouadi, R, Shephard, RJ, and Chelly, MS. Effects of an in-season plyometric training program on repeated change of direction and sprint performance in the junior soccer player. J Strength Cond Res 30(12): 3312-3320, 2016-We aimed to determine the gains in explosive movements of male junior soccer players induced by incorporating an 8-week plyometric training program (PTP) into a standard soccer conditioning regimen 5 months after the beginning of the competitive season. Our hypothesis was that PTP would enhance explosive movements, and thus sprint running, repeated shuttle sprint ability (RSSA), agility and the ability to make repeated changes of direction (RCOD). A group of junior soccer players were randomly divided into 2 groups: an experimental group (E, n = 15, age 15.7 ± 0.2 years) and a control group (C, n = 13, age 15.8 ± 0.2 years). The participants in E and C performed training exercises and matches together, but for an 8-week period in the latter part of the season, the experimental group replaced a part of the normal regimen (the tactical session) by a biweekly course of PTP (hurdle and drop jumps). Two familiarization sessions were held 2 weeks before definitive testing. The ability of the players was assessed by 3 agility tests (a sprint test with 180° turns, a 9-3-6-3-9 m sprint with backward and forward running, and a four 5-m sprint test with turns); 2 repeated sprint tests (RSSA and RCOD); and running times over 5-, 10-, 20-, 30-, and 40-m distances. Participants in E showed gains relative to C in sprint times (p ≤ 0.05 for 5, 10, and 20 m), and 2 of 3 the RCOD parameters (RCOD best, p ≤ 0.001; RCOD total, p ≤ 0.05). However, with the pattern of plyometric training that we adopted, and perhaps because participants were in good initial physical condition, the agility and RSSA test scores remained unchanged. Nevertheless, we conclude that our PTP can be commended to junior soccer players as a means of improving important components of their physical performance.

Plyometric Training Effects on Athletic Performance in Youth Soccer Athletes: A Systematic Review.

PubMed

Bedoya, Abigail A; Miltenberger, Matthew R; Lopez, Rebecca M

2015-08-01

The purpose of this systematic review was to critically analyze the literature to determine the effectiveness of plyometric training on athletic performance in youth soccer athletes. A total of 7 studies were included in this review after meeting the following criteria: (a) used plyometric training programs to assess athletic performance, (b) subjects were soccer athletes aged preadolescent up to 17 years, and (c) were published from 2000 to January 2014. Study methods were assessed using the PEDro scale with scores ranging from 4 to 6. Results showed similarities and differences in methodologies and procedures among the included studies. Athletic performance consisting of kicking distance, speed, jumping ability, and agility significantly improved because of plyometric training interventions. The current evidence suggests that plyometric training should be completed 2 days per week for 8-10 weeks during soccer practice with a 72-hour rest period between plyometric training days. The initial number of foot contacts should be 50-60 per session and increase to no more than 80-120 foot contacts per session for this age group to prevent overuse injuries. A total of 3-4 plyometric training exercises should be performed 2-4 sets for 6-15 repetitions per training session. The evidence and the literature suggest that plyometric training for this age group should only be implemented using recommended safety guidelines such as those published by the Canadian Society for Exercise Physiology and the National Strength and Conditioning Association and under appropriate supervision by trained personnel.

Strength and endurance training reduces the loss of eccentric hamstring torque observed after soccer specific fatigue.

PubMed

Matthews, Martyn J; Heron, Kate; Todd, Stefanie; Tomlinson, Andrew; Jones, Paul; Delextrat, Anne; Cohen, Daniel D

2017-05-01

To investigate the effect of two hamstring training protocols on eccentric peak torque before and after soccer specific fatigue. Twenty-two university male soccer players. Isokinetic strength tests were performed at 60°/s pre and post fatigue, before and after 2 different training interventions. A 45-min soccer specific fatigue modified BEAST protocol (M-BEAST) was used to induce fatigue. Players were randomly assigned to a 4 week hamstrings conditioning intervention with either a maximum strength (STR) or a muscle endurance (END) emphasis. The following parameters were evaluated: Eccentric peak torque (EccPT), angle of peak torque (APT), and angle specific torques at knee joint angles of 10°, 20°, 30°, 40°, 50°, 60°, 70°, 80° and 90°. There was a significant effect of the M-BEAST on the Eccentric torque angle profile before training as well as significant improvements in post-fatigue torque angle profile following the effects of both strength and muscle endurance interventions. Forty-five minutes of simulated soccer activity leads to reduced eccentric hamstring torque at longer muscle lengths. Short-term conditioning programs (4-weeks) with either a maximum strength or a muscular endurance emphasis can equally reduce fatigue induced loss of strength over this time period. Copyright © 2017 Elsevier Ltd. All rights reserved.

Scapular resting position, shoulder pain and function in disabled athletes.

PubMed

Aytar, Aydan; Zeybek, Aslican; Pekyavas, Nihan Ozunlu; Tigli, Ayca Aytar; Ergun, Nevin

2015-10-01

Despite the fact that the number of disabled individuals participating in sports is increasing, there are only sparse reports in the literature concerning overuse injuries. The purpose of this study was to compare scapular resting position, shoulder pain, and function in wheelchair basketball, amputee soccer, and disabled table tennis players. Descriptive study. A total of 63 disabled players from amputee soccer, wheelchair basketball, and disabled table tennis participated in our study. Scapular resting position was taken as primary outcome; pain and function were taken as secondary outcome measurements. Scapular resting position was evaluated with Lateral Scapular Slide Test. Visual Analog Scale was used for evaluating shoulder pain intensity. Quick disabilities of the arm, shoulder, and hand questionnaire were used to assess upper extremity function. There was a significant difference in shoulder pain, function, and scapular resting position in all groups (p < 0.05). Paired comparisons between amputee soccer and wheelchair basketball players and also amputee soccer and disabled table tennis showed difference for all measurement parameters (p < 0.05). When the results are evaluated, it may be stated that amputee soccer players have better scapular resting position than other sports. Crutch usage may not negatively affect scapular resting position and perceived function as much as wheelchair usage. Exercise techniques for shoulder and resting position could be included in training programs of disabled athletes. Wheelchair/crutch usage is a risk, and special exercise techniques for shoulder and dyskinesis could be included in training programs to prevent injury. However, it may not just be important for wheelchair athletes, it may also be important for amputee soccer players. In particular, total upper extremity evaluations and exercises could be added within exercise programs. © The International Society for Prosthetics and Orthotics 2014.

Effects of Plyometric Training and Beta-Alanine Supplementation on Maximal-Intensity Exercise and Endurance in Female Soccer Players

PubMed Central

Rosas, Fabián; Ramírez-Campillo, Rodrigo; Martínez, Cristian; Cañas-Jamet, Rodrigo; McCrudden, Emma; Meylan, Cesar; Moran, Jason; Nakamura, Fábio Y.; Pereira, Lucas A.; Loturco, Irineu; Diaz, Daniela; Izquierdo, Mikel

2017-01-01

Abstract Plyometric training and beta-alanine supplementation are common among soccer players, although its combined use had never been tested. Therefore, a randomized, double-blind, placebo-controlled trial was conducted to compare the effects of a plyometric training program, with or without beta-alanine supplementation, on maximal-intensity and endurance performance in female soccer players during an in-season training period. Athletes (23.7 ± 2.4 years) were assigned to either a plyometric training group receiving a placebo (PLACEBO, n = 8), a plyometric training group receiving beta-alanine supplementation (BA, n = 8), or a control group receiving placebo without following a plyometric training program (CONTROL, n = 9). Athletes were evaluated for single and repeated jumps and sprints, endurance, and change-of-direction speed performance before and after the intervention. Both plyometric training groups improved in explosive jumping (ES = 0.27 to 1.0), sprinting (ES = 0.31 to 0.78), repeated sprinting (ES = 0.39 to 0.91), 60 s repeated jumping (ES = 0.32 to 0.45), endurance (ES = 0.35 to 0.37), and change-of-direction speed performance (ES = 0.36 to 0.58), whereas no significant changes were observed for the CONTROL group. Nevertheless, compared to the CONTROL group, only the BA group showed greater improvements in endurance, repeated sprinting and repeated jumping performances. It was concluded that beta-alanine supplementation during plyometric training may add further adaptive changes related to endurance, repeated sprinting and jumping ability. PMID:28828081

Effects of Plyometric Training and Beta-Alanine Supplementation on Maximal-Intensity Exercise and Endurance in Female Soccer Players.

PubMed

Rosas, Fabián; Ramírez-Campillo, Rodrigo; Martínez, Cristian; Caniuqueo, Alexis; Cañas-Jamet, Rodrigo; McCrudden, Emma; Meylan, Cesar; Moran, Jason; Nakamura, Fábio Y; Pereira, Lucas A; Loturco, Irineu; Diaz, Daniela; Izquierdo, Mikel

2017-09-01

Plyometric training and beta-alanine supplementation are common among soccer players, although its combined use had never been tested. Therefore, a randomized, double-blind, placebo-controlled trial was conducted to compare the effects of a plyometric training program, with or without beta-alanine supplementation, on maximal-intensity and endurance performance in female soccer players during an in-season training period. Athletes (23.7 ± 2.4 years) were assigned to either a plyometric training group receiving a placebo (PLACEBO, n = 8), a plyometric training group receiving beta-alanine supplementation (BA, n = 8), or a control group receiving placebo without following a plyometric training program (CONTROL, n = 9). Athletes were evaluated for single and repeated jumps and sprints, endurance, and change-of-direction speed performance before and after the intervention. Both plyometric training groups improved in explosive jumping (ES = 0.27 to 1.0), sprinting (ES = 0.31 to 0.78), repeated sprinting (ES = 0.39 to 0.91), 60 s repeated jumping (ES = 0.32 to 0.45), endurance (ES = 0.35 to 0.37), and change-of-direction speed performance (ES = 0.36 to 0.58), whereas no significant changes were observed for the CONTROL group. Nevertheless, compared to the CONTROL group, only the BA group showed greater improvements in endurance, repeated sprinting and repeated jumping performances. It was concluded that beta-alanine supplementation during plyometric training may add further adaptive changes related to endurance, repeated sprinting and jumping ability.

The Yo-Yo IR2 test: physiological response, reliability, and application to elite soccer.

PubMed

Oberacker, Lisa M; Davis, Shala E; Haff, G Gregory; Witmer, Chad A; Moir, Gavin L

2012-10-01

The purpose of this study was to compare the effects of resistance training performed on either a stable or unstable surface on performance tests in female soccer players. Nineteen National Collegiate Athletic Association Division II female soccer players were assigned to either an unstable training group (UST: 19.0 ± 0.47 years; 1.69 ± 6.4 m; 67.8 ± 7.7 kg) or a stable training group (ST: 19.6 ± 0.49 years; 1.64 ± 3.2 m; 62.7 ± 6.27 kg). Player positions were distributed evenly between the groups. Both the groups followed a 5-week periodized resistance training program designed to develop maximum muscular strength. The groups performed the same exercises during each workout, with the UST performing 2 of the exercises in each session on an unstable surface. Pretraining and posttraining measures of straight-line sprint speed, planned and reactive agility, aerobic capacity, and countermovement vertical jump (CMJ) were taken. Significant main effects for time were reported for straight-line sprint speed, planned agility, and reactive agility with both groups demonstrating improvements during the posttraining testing session. The ST demonstrated a significant increase in CMJ during the posttraining session (change in mean: 0.04 m) in contrast to the decline demonstrated by the UST (change in mean: -0.01 m). Performing resistance training exercises on an unstable surface confers no advantage over traditional resistance training exercises for improving the speed, agility, and aerobic capacity of female soccer players. Furthermore, the use of an unstable surface may inhibit the effects of resistance training on vertical jump height, an important variable in soccer performance.

The Effects of in-Season Repeated Sprint Training Compared to Regular Soccer Training.

PubMed

Nedrehagen, Eirik Solberg; Saeterbakken, Atle Hole

2015-12-22

The aim of this study was to compare the effects of repeated sprints (RSA) training and regular soccer training on Yo-Yo IR-1 and RSA performance (6 x 40 m shuttle sprints). Thirteen semi-professional female soccer players and nine amateur male soccer players were randomised into a repeated sprint group (RSG; n = 12) or a regular soccer training group (STG; n = 10). The RSG soccer players executed 3-4 sets of 4-6 repeated sprints (30 m with 180° directional changes) weekly during the last eight weeks of the in-season. In parallel, the STG soccer players performed low- to moderate intensity soccer training in form of technical or tactical skills. The RSG showed 15% improvement in Yo-Yo IR-1 (p = 0.04; ES = 1.83) and their mean RSA times were reduced by 1.5% (p = 0.02; ES = 0.89). No significant changes were found for the STG (Yo-Yo IR-1, p = 0.13; RSA, p = 0.49). Comparing the groups, greater improvements were observed in Yo-Yo IR-1 for the RSG (p = 0.02; ES = 1.15), but not for the RSA (p = 0.23; ES = -0.33). Similar training volumes and intensities (% of HFmax) were observed between the groups (p = 0.22 and p = 0.79). In conclusion, a weekly RSA session integrated into a regular soccer regime improved in-season RSA and Yo-Yo IR-1 performance compared to regular soccer training.

Effects of a Summer Treatment Program on Functional Sports Outcomes in Young Children with ADHD

PubMed Central

Fabiano, Gregory A.; Waschbusch, Daniel A.; Belin, Peter J.; Gnagy, Elizabeth M.; Pelham, William E.; Greiner, Andrew R.; Roemmich, James N.

2015-01-01

Participation in youth sports can be very beneficial, but children with Attention Deficit Hyperactivity Disorder (ADHD) may participate less often and less successfully. The current study evaluated functional sports outcomes for children with ADHD who attended an intensive behavioral treatment program that included a sports training component, and it compared outcomes to children with ADHD who did not attend the program. Results suggest that treatment resulted in significant improvements in many aspects of children’s sports functioning, including knowledge of game rules, in vivo game performance, and fundamental skill tasks (motor proficiency, ability to trap a soccer ball appropriately, reduced handball penalties in soccer, and improved ability to catch a baseball). Parents also reported improved sports skills and good sportsmanship in the treatment group. No differences between groups were evident on additional skill tasks evaluating accurately kicking a soccer ball, throwing a baseball, or hitting a baseball off a tee. These results suggest intensive behavioral intervention that includes sports training can significantly improve functional sports outcomes for young children with ADHD. PMID:24362766

High-Intensity Training and Salivary Immunoglobulin A Responses in Professional Top-Level Soccer Players: Effect of Training Intensity.

PubMed

Owen, Adam L; Wong, Del P; Dunlop, Gordon; Groussard, Carole; Kebsi, Wiem; Dellal, Alexandre; Morgans, Ryland; Zouhal, Hassane

2016-09-01

Owen, AL, Wong, DP, Dunlop, G, Groussard, C, Kebsi, W, Dellal, A, Morgans, R, and Zouhal, H. High-intensity training and salivary immunoglobulin A responses in professional top-level soccer players: Effect of training intensity. J Strength Cond Res 30(9): 2460-2469, 2016-This study aimed (a) to test the hypothesis that salivary immunoglobulin A (s-IgA) would vary with training intensity sessions (low-intensity [LI] vs. high-intensity sessions [HI]) during a traditional training program divided into 4 training periods and (b) to identify key variables (e.g., GPS data, rating of perceived exertion [RPE], and training duration), which could affect s-IgA. Saliva samples of 10 elite professional soccer players were collected (a) before the investigation started to establish the baseline level and (b) before and after each 4 training sessions (LI vs. HI). Training intensity was monitored as internal (through heart rate responses and RPE) and external (through GPS) loads. High-intensity sessions were associated with higher external load (GPS) and with higher RPE. Baseline and pretraining s-IgA did not differ between the 4 training sessions both for HI and LI. Post-training s-IgA were not different (in absolute value and in percentage of change) between HI and LI sessions at the first 3 periods. However, at the fourth period, s-IgA concentration for HI session was significantly lower (p ≤ 0.05) than the LI session. The percentage change between s-IgA post-training and s-IgA baseline concentrations differ significantly (p ≤ 0.05) between HI and LI training sessions. Significant correlations between s-IgA and training intensity were also noted. High-intensity soccer training sessions might cause a significant decrease in s-IgA values during the postexercise window as compared with LI sessions. This study encourages coaches to monitor s-IgA in routine, particularly during HI training periods, to take precautions to avoid upper respiratory tract infection in highly trained soccer players.

The effects of interday rest on adaptation to 6 weeks of plyometric training in young soccer players.

PubMed

Ramírez-Campillo, Rodrigo; Meylan, César M P; Álvarez-Lepín, Cristian; Henriquez-Olguín, Carlos; Martinez, Cristian; Andrade, David C; Castro-Sepúlveda, Mauricio; Burgos, Carlos; Baez, Eduardo I; Izquierdo, Mikel

2015-04-01

The purpose of this study was to determine the effects of short-term plyometric training interposed with 24 or 48 hours of rest between training sessions on explosive and endurance adaptations in young soccer players. A total of 166 players, between 10 and 17 years of age, were randomly divided into 3 groups: a control group (CG; n = 55) and 2 plyometric training groups with 24 hours (PT24; n = 54) and 48 hours (PT48; n = 57) of rest between training sessions. Before and after intervention, players were measured in squat jump, countermovement jump, 20 (RSI20) cm drop jump reactive strength index, broad long jump, 20-m sprint time, 10 × 5-m agility time, 20-m multistage shuttle run test, and sit-and-reach test. The plyometric training program was applied during 6 weeks, 2 sessions per week, with a load from 140 to 260 jumps per session, replacing some soccer-specific drills. After intervention, the CG did not show significant performance changes. PT24 and PT48 groups showed a small-to-moderate significant improvement in all performance tests (p < 0.001), with no differences between treatments. Although it has been recommended that plyometric drills should not be conducted on consecutive days, the study shows that plyometric training applied twice weekly on consecutive or nonconsecutive days results in similar explosive and endurance adaptations in young male soccer players.

Neuromuscular and athletic performance following core strength training in elite youth soccer: Role of instability.

PubMed

Prieske, O; Muehlbauer, T; Borde, R; Gube, M; Bruhn, S; Behm, D G; Granacher, U

2016-01-01

Cross-sectional studies revealed that inclusion of unstable elements in core-strengthening exercises produced increases in trunk muscle activity and thus potential extra stimuli to induce more pronounced performance enhancements in youth athletes. Thus, the purpose of the study was to investigate changes in neuromuscular and athletic performance following core strength training performed on unstable (CSTU) compared with stable surfaces (CSTS) in youth soccer players. Thirty-nine male elite soccer players (age: 17 ± 1 years) were assigned to two groups performing a progressive core strength-training program for 9 weeks (2-3 times/week) in addition to regular in-season soccer training. CSTS group conducted core exercises on stable (i.e., floor, bench) and CSTU group on unstable (e.g., Thera-Band® Stability Trainer, Togu© Swiss ball) surfaces. Measurements included tests for assessing trunk muscle strength/activation, countermovement jump height, sprint time, agility time, and kicking performance. Statistical analysis revealed significant main effects of test (pre vs post) for trunk extensor strength (5%, P < 0.05, d = 0.86), 10-20-m sprint time (3%, P < 0.05, d = 2.56), and kicking performance (1%, P < 0.01, d = 1.28). No significant Group × test interactions were observed for any variable. In conclusion, trunk muscle strength, sprint, and kicking performance improved following CSTU and CSTS when conducted in combination with regular soccer training. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Does SAQ training improve the speed and flexibility of young soccer players? A randomized controlled trial.

PubMed

Milanović, Zoran; Sporiš, Goran; Trajković, Nebojsa; Sekulić, Damir; James, Nic; Vučković, Goran

2014-12-01

The aim of this study was to determine the effects of a 12 week speed, agility and quickness (SAQ) training program on speed and flexibility in young soccer players. One hundred and thirty-two soccer players were randomly assigned to experimental (EG; n=66, mean±SD: age: 18.5±0.4 years (range 17-19 years); body mass: 71.30±5.93 kg; stature: 177.2±6.5 cm) and control groups (CG; n=66, mean±SD: age: 18.6±0.6 years (range 17-19 years); body mass: 70.63±4.87 kg; stature: 175.9±5.7 cm). The experimental group performed SAQ training whilst the control group undertook straight-line sprint training matched for volume and duration. Sprint performance was assessed using 5 and 10 m sprints and a further test including maximal speed, a 20 m sprint. Flexibility was assessed using sit and reach, V-sit and reach, leg lift from supine position and lateral leg lift while lying on the side tests. Sprints over 5, 10 and 20 m did not differ between groups at baseline, but by week 12, the 5m sprint had significantly improved (P<.05) in the SAQ training group compared to the control group (1.40±0.13 vs. 1.46±0.12s, respectively) although this improvement had a trivial effect size (ES=0.15). The 10 m sprint time had improved by 3.3% (P<.01) in the SAQ group with a moderate effect size (ES=0.66). No significant differences (P>.05) for all flexibility tests were found between experimental and control group at baseline and after the training programs. Consequently SAQ training was found to be an effective way of improving sprint time for short distances over 5 and 10 m but not over 20 m (where maximum speed was achieved) or flexibility. These results indicate that SAQ training may be more effective for improving sprint performance for some soccer players but more research is required to determine ideal training methods for improving acceleration and flexibility in young soccer players. Copyright © 2014 Elsevier B.V. All rights reserved.

Differential Learning as a Key Training Approach to Improve Creative and Tactical Behavior in Soccer

ERIC Educational Resources Information Center

Santos, Sara; Coutinho, Diogo; Gonçalves, Bruno; Schöllhorn, Wolfgang; Sampaio, Jaime; Leite, Nuno

2018-01-01

Purpose: The aim of this study was to identify the effects of a differential-learning program, embedded in small-sided games, on the creative and tactical behavior of youth soccer players. Forty players from under-13 (U13) and under-15 (U15) were allocated into control and experimental groups and were tested using a randomized pretest to posttest…

Training Guide to Cerebral Palsy Sports. Third Edition.

ERIC Educational Resources Information Center

Jones, Jeffery A., Ed.

This official training manual of the United States Cerebral Palsy Athletic Association includes the latest coaching and training techniques specific to all sports in the national program. The book features guidelines for coaching over a dozen sports, including soccer, swimming, cycling, and track and field. It contains everything coaches,…

Prophylactic training in asymptomatic soccer players with ultrasonographic abnormalities in Achilles and patellar tendons: the Danish Super League Study.

PubMed

Fredberg, Ulrich; Bolvig, Lars; Andersen, Niels T

2008-03-01

A recent study published in The American Journal of Sports Medicine showed that asymptomatic soccer players with an increased risk of developing Achilles and patellar tendon injuries within the next 12 months can be identified with use of ultrasonography. Prophylactic eccentric training and stretching can reduce both the frequency of asymptomatic ultrasonographic changes in Achilles and patellar tendons in soccer players and the risk of these asymptomatic intratendinous changes becoming symptomatic. Randomized controlled trial; Level of evidence, 1. Two hundred and nine Danish professional soccer players from the best national league (Super League) were followed over 12 months with use of ultrasonography and injury registration. Half the teams were randomized to an intervention group with prophylactic eccentric training and stretching of the Achilles and patellar tendons during the soccer season. The eccentric training and stretching did not reduce the injury risk, and, contrary to all expectations, the injury risk during the season was increased in players with abnormal patellar tendons at the beginning of the study in January. Eccentric training and stretching in players with normal patellar tendons significantly reduced the proportion of players with ultrasonographic changes in the patellar tendons at the end of the season (risk difference [RD] = 12%; 95% confidence interval [CI], 2%-22%; P = .02), but the training had no effect on the Achilles tendons (RD = 1%; 95% CI, -7% to 9%; P = .75). The presence of preseason ultrasonographic abnormalities in the tendons significantly increased the risk of developing tendon symptoms during the season (relative risk = 1.9; 95% CI, 1.2-3.1; P = .009). This study demonstrates that with the use of ultrasonography, tendon changes in soccer players can be diagnosed before they become symptomatic. The prophylactic eccentric training and stretching program reduces the risk of developing ultrasonographic abnormalities in the patellar tendons but has no positive effects on the risk of injury. On the contrary, in asymptomatic players with ultrasonographically abnormal patellar tendons, prophylactic eccentric training and stretching increased the injury risk.

Effect of Core Training on 16 Year-Old Soccer Players

ERIC Educational Resources Information Center

Afyon, Yakup Akif

2014-01-01

Core trainings have been widely used by trainers recently in order to improve performance of soccer players. In this context, the aim of this study is to examine the effect of core training on some motoric capabilities of 16 years old soccer players. Thirty certified soccer players who were 16 years old from B.B. Bodrumspor Club in 2013-2014…

Effects of Soccer Training on Anthropometry, Body Composition, and Physical Fitness during a Soccer Season in Female Elite Young Athletes: A Prospective Cohort Study.

PubMed

Lesinski, Melanie; Prieske, Olaf; Helm, Norman; Granacher, Urs

2017-01-01

The objectives of this study were to (i) describe soccer training (e.g., volume, types), anthropometry, body composition, and physical fitness and (ii) compute associations between soccer training data and relative changes of anthropometry, body composition, and physical fitness during a soccer season in female elite young athletes. Seasonal training (i.e., day-to-day training volume/types) as well as variations in anthropometry (e.g., body height/mass), body composition (e.g., lean body/fat mass), and physical fitness (e.g., muscle strength/power, speed, balance) were collected from 17 female elite young soccer players (15.3 ± 0.5 years) over the training periods (i.e., preparation, competition, transition) of a soccer season that resulted in the German championship title in under-17 female soccer. Training volume/types, anthropometrics, body composition, and physical fitness significantly varied over a soccer season. During the two preparation periods, higher volumes in resistance and endurance training were performed (2.00 ≤ d ≤ 18.15; p < 0.05), while higher sprint and tactical training volumes were applied during the two competition periods (2.22 ≤ d ≤ 11.18; p < 0.05). Body height and lean body mass increased over the season (2.50 ≤ d ≤ 3.39; p < 0.01). In terms of physical fitness, significant performance improvements were found over the soccer season in measures of balance, endurance, and sport-specific performance (2.52 ≤ d ≤ 3.95; p < 0.05). In contrast, no statistically significant changes were observed for measures of muscle power/endurance, speed, and change-of-direction speed. Of note, variables of muscle strength (i.e., leg extensors) significantly decreased ( d = 2.39; p < 0.01) over the entire season. Our period-specific sub-analyses revealed significant performance improvements during the first round of the season for measures of muscle power/endurance, and balance (0.89 ≤ d ≤ 4.01; p < 0.05). Moreover, change-of-direction speed significantly declined after the first round of the season, i.e., transition period ( d = 2.83; p < 0.01). Additionally, significant medium-to-large associations were observed between training and anthropometrics/body composition/physical fitness (-0.541 ≤ r ≤ 0.505). Soccer training and/or growth/maturation contributed to significant variations in anthropometry, body composition, and physical fitness outcomes throughout the different training periods over the course of a soccer season in female elite young soccer players. However, changes in components of fitness were inconsistent (e.g., power, speed, strength). Thus, training volume and/or types should be carefully considered in order to develop power-, speed- or strength-related fitness measures more efficiently throughout the soccer season.

Effects of Soccer Training on Anthropometry, Body Composition, and Physical Fitness during a Soccer Season in Female Elite Young Athletes: A Prospective Cohort Study

PubMed Central

Lesinski, Melanie; Prieske, Olaf; Helm, Norman; Granacher, Urs

2017-01-01

The objectives of this study were to (i) describe soccer training (e.g., volume, types), anthropometry, body composition, and physical fitness and (ii) compute associations between soccer training data and relative changes of anthropometry, body composition, and physical fitness during a soccer season in female elite young athletes. Seasonal training (i.e., day-to-day training volume/types) as well as variations in anthropometry (e.g., body height/mass), body composition (e.g., lean body/fat mass), and physical fitness (e.g., muscle strength/power, speed, balance) were collected from 17 female elite young soccer players (15.3 ± 0.5 years) over the training periods (i.e., preparation, competition, transition) of a soccer season that resulted in the German championship title in under-17 female soccer. Training volume/types, anthropometrics, body composition, and physical fitness significantly varied over a soccer season. During the two preparation periods, higher volumes in resistance and endurance training were performed (2.00 ≤ d ≤ 18.15; p < 0.05), while higher sprint and tactical training volumes were applied during the two competition periods (2.22 ≤ d ≤ 11.18; p < 0.05). Body height and lean body mass increased over the season (2.50 ≤ d ≤ 3.39; p < 0.01). In terms of physical fitness, significant performance improvements were found over the soccer season in measures of balance, endurance, and sport-specific performance (2.52 ≤ d ≤ 3.95; p < 0.05). In contrast, no statistically significant changes were observed for measures of muscle power/endurance, speed, and change-of-direction speed. Of note, variables of muscle strength (i.e., leg extensors) significantly decreased (d = 2.39; p < 0.01) over the entire season. Our period-specific sub-analyses revealed significant performance improvements during the first round of the season for measures of muscle power/endurance, and balance (0.89 ≤ d ≤ 4.01; p < 0.05). Moreover, change-of-direction speed significantly declined after the first round of the season, i.e., transition period (d = 2.83; p < 0.01). Additionally, significant medium-to-large associations were observed between training and anthropometrics/body composition/physical fitness (−0.541 ≤ r ≤ 0.505). Soccer training and/or growth/maturation contributed to significant variations in anthropometry, body composition, and physical fitness outcomes throughout the different training periods over the course of a soccer season in female elite young soccer players. However, changes in components of fitness were inconsistent (e.g., power, speed, strength). Thus, training volume and/or types should be carefully considered in order to develop power-, speed- or strength-related fitness measures more efficiently throughout the soccer season. PMID:29375392

Injuries in Portuguese Youth Soccer Players During Training and Match Play

PubMed Central

Brito, João; Malina, Robert M.; Seabra, André; Massada, José L.; Soares, José M.; Krustrup, Peter; Rebelo, António

2012-01-01

Context: Epidemiologic information on the incidence of youth soccer injuries in southern Europe is limited. Objective: To compare the incidence, type, location, and severity of injuries sustained by male subelite youth soccer players over the 2008–2009 season. Design: Descriptive epidemiology study. Setting: Twenty-eight Portuguese male youth soccer teams. Patients or Other Participants: A total of 674 youth male subelite soccer players in 4 age groups: 179 U-13 (age range, 11–12 years), 169 U-15 (age range, 13–14 years), 165 U-17 (age range, 15–16 years), and 161 U-19 (age range, 17–18 years). Main Outcome Measure(s): Injuries that led to participation time missed from training and match play prospectively reported by medical or coaching staff of the clubs. Results: In total, 199 injuries reported in 191 players accounted for 14.6 ± 13.0 days of absence from practice. The incidence was 1.2 injuries per 1000 hours of exposure to soccer (95% confidence interval [CI] = 0.8, 1.6), with a 4.2-fold higher incidence during match play (4.7 injuries per 1000 hours of exposure; 95% CI = 3.0, 6.5) than during training (0.9 injuries per 1000 hours of exposure; 95% CI = 0.6, 1.3) (F1,673 = 17.592, P < .001). The overall incidence of injury did not increase with age (F1,673 = 1.299, P = .30), and the incidence of injury during matches (F1,673 = 2.037, P = .14) and training (F1,673 = 0.927, P = .44) did not differ among age groups. Collisions accounted for 57% (n = 113) of all injuries, but participation time missed due to traumatic injury did not differ among age groups (F3,110 = 1.044, P = .38). Most injuries (86%, n = 172) involved the lower extremity. The thigh was the most affected region (30%, n = 60) in all age groups. Muscle strains were the most common injuries among the U-19 (34%, n = 26), U-17 (30%, n = 17), and U-15 (34%, n = 14) age groups, whereas contusions and tendon injuries were the most common injuries in U-13 players (both 32%, n = 8). The relative risk of injury slightly increased with the age of the competitors. Conclusions: The higher incidence of injury during matches than training highlights the need for education and prevention programs in youth soccer. These programs should focus on coach education aimed at improving skills, techniques, and fair play during competitions with the goal of reducing injuries. PMID:22488285

Sprint Conditioning of Junior Soccer Players: Effects of Training Intensity and Technique Supervision

PubMed Central

Haugen, Thomas; Tønnessen, Espen; Øksenholt, Øyvind; Haugen, Fredrik Lie; Paulsen, Gøran; Enoksen, Eystein; Seiler, Stephen

2015-01-01

The aims of the present study were to compare the effects of 1) training at 90 and 100% sprint velocity and 2) supervised versus unsupervised sprint training on soccer-specific physical performance in junior soccer players. Young, male soccer players (17 ±1 yr, 71 ±10 kg, 180 ±6 cm) were randomly assigned to four different treatment conditions over a 7-week intervention period. A control group (CON, n=9) completed regular soccer training according to their teams’ original training plans. Three training groups performed a weekly repeated-sprint training session in addition to their regular soccer training sessions performed at A) 100% intensity without supervision (100UNSUP, n=13), B) 90% of maximal sprint velocity with supervision (90SUP, n=10) or C) 90% of maximal sprint velocity without supervision (90UNSUP, n=13). Repetitions x distance for the sprint-training sessions were 15x20 m for 100UNSUP and 30x20 m for 90SUP and 90UNSUP. Single-sprint performance (best time from 15x20 m sprints), repeated-sprint performance (mean time over 15x20 m sprints), countermovement jump and Yo-Yo Intermittent Recovery Level 1 (Yo-Yo IR1) were assessed during pre-training and post-training tests. No significant differences in performance outcomes were observed across groups. 90SUP improved Yo-Yo IR1 by a moderate margin compared to controls, while all other effect magnitudes were trivial or small. In conclusion, neither weekly sprint training at 90 or 100% velocity, nor supervised sprint training enhanced soccer-specific physical performance in junior soccer players. PMID:25798601

The Effects of a 6-Week Strength Training on Critical Velocity, Anaerobic Running Distance, 30-M Sprint and Yo-Yo Intermittent Running Test Performances in Male Soccer Players.

PubMed

Karsten, Bettina; Larumbe-Zabala, Eneko; Kandemir, Gokhan; Hazir, Tahir; Klose, Andreas; Naclerio, Fernando

2016-01-01

The objectives of this study were to examine the effects of a moderate intensity strength training on changes in critical velocity (CV), anaerobic running distance (D'), sprint performance and Yo-Yo intermittent running test (Yo-Yo IR1) performances. two recreational soccer teams were divided in a soccer training only group (SO; n = 13) and a strength and soccer training group (ST; n = 13). Both groups were tested for values of CV, D', Yo-Yo IR1 distance and 30-m sprint time on two separate occasions (pre and post intervention). The ST group performed a concurrent 6-week upper and lower body strength and soccer training, whilst the SO group performed a soccer only training. after the re-test of all variables, the ST demonstrated significant improvements for both, YoYo IR1 distance (p = 0.002) and CV values (p<0.001) with no significant changes in the SO group. 30-m sprint performance were slightly improved in the ST group with significantly decreased performance times identified in the SO group (p<0.001). Values for D' were slightly reduced in both groups (ST -44.5 m, 95% CI = -90.6 to 1.6; SO -42.6 m, 95% CI = -88.7 to 3.5). combining a 6-week moderate strength training with soccer training significantly improves CV, Yo-Yo IR1 whilst moderately improving 30-m sprint performances in non-previously resistance trained male soccer players. Critical Velocity can be recommended to coaches as an additional valid testing tool in soccer.

The Effects of a 6-Week Strength Training on Critical Velocity, Anaerobic Running Distance, 30-M Sprint and Yo-Yo Intermittent Running Test Performances in Male Soccer Players

PubMed Central

Karsten, Bettina; Larumbe-Zabala, Eneko; Kandemir, Gokhan; Hazir, Tahir; Klose, Andreas; Naclerio, Fernando

2016-01-01

The objectives of this study were to examine the effects of a moderate intensity strength training on changes in critical velocity (CV), anaerobic running distance (D'), sprint performance and Yo-Yo intermittent running test (Yo-Yo IR1) performances. Methods: two recreational soccer teams were divided in a soccer training only group (SO; n = 13) and a strength and soccer training group (ST; n = 13). Both groups were tested for values of CV, D', Yo-Yo IR1 distance and 30-m sprint time on two separate occasions (pre and post intervention). The ST group performed a concurrent 6-week upper and lower body strength and soccer training, whilst the SO group performed a soccer only training. Results: after the re-test of all variables, the ST demonstrated significant improvements for both, YoYo IR1 distance (p = 0.002) and CV values (p<0.001) with no significant changes in the SO group. 30-m sprint performance were slightly improved in the ST group with significantly decreased performance times identified in the SO group (p<0.001). Values for D' were slightly reduced in both groups (ST -44.5 m, 95% CI = -90.6 to 1.6; SO -42.6 m, 95% CI = -88.7 to 3.5). Conclusions: combining a 6-week moderate strength training with soccer training significantly improves CV, Yo-Yo IR1 whilst moderately improving 30-m sprint performances in non-previously resistance trained male soccer players. Critical Velocity can be recommended to coaches as an additional valid testing tool in soccer. PMID:27015418

Effects of light-load maximal lifting velocity weight training vs. combined weight training and plyometrics on sprint, vertical jump and strength performance in adult soccer players.

PubMed

Rodríguez-Rosell, David; Torres-Torrelo, Julio; Franco-Márquez, Felipe; González-Suárez, José Manuel; González-Badillo, Juan José

2017-07-01

The purpose of this study was to compare the effects of combined light-load maximal lifting velocity weight training (WT) and plyometric training (PT) with WT alone on strength, jump and sprint performance in semiprofessional soccer players. Experimental, pre-post tests measures. Thirty adult soccer players were randomly assigned into three groups: WT alone (FSG, n=10), WT combined to jump and sprint exercises (COM, n=10) and control group (CG, n=10). WT consisted of full squat with low load (∼45-60% 1RM) and low volume (4-6 repetitions). Training program was performed twice a week for 6 weeks of competitive season in addition to 4 soccer sessions a week. Sprint time in 10 and 20m, jump height (CMJ), estimated one-repetition maximum (1RM est ) and velocity developed against different absolute loads in full squat were measured before and after training period. Both experimental groups showed significant improvements in 1RM est (17.4-13.4%; p<0.001), CMJ (7.1-5.2%; p<0.001), sprint time (3.6-0.7%; p<0.05-0.001) and force-velocity relationships (16.9-6.1%; p<0.05-0.001), whereas no significant gains were found in CG. No significant differences were found between FSG and COM. Despite FSG resulted of greater increases in strength variables than COM, this may not translate into superior improvements in the sport-related performance. In fact, COM showed higher efficacy of transfer of strength gains to sprint ability. Therefore, these findings suggest that a combined WT and PT program could represent a more efficient method for improving activities which involve acceleration, deceleration and jumps compared to WT alone. Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

[PREVALENCE OF DEHYDRATION BEFORE TRAINING IN PROFESIONAL CHILEAN SOCCER PLAYERS].

PubMed

Castro-Sepúlveda, Mauricio; Astudillo, Sebastian; Álvarez, Cristian; Zapata-Lamana, Rafael; Zbinden-Foncea, Hermann; Ramírez-Campillo, Rodrigo; Jorquera, Carlos

2015-07-01

there is a lack of studies concerning hydration status before training in professional soccer player. to describe hydration status before regular training practices in professional soccer players. a total of 156 male soccer players (age 25.4 ± 5.2 y) from six professional Chilean clubs were included. No hydration or food intake recommendations were made before experiment, with the aim to assess hydration status under athlete's regular "real" conditions. Body mass, height and urine specific gravity (USG) measurements were performed before training practices. 98% of athletes showed dehydration (between moderate and severe) before regular training practices. dehydration is the most prevalent hydration status in professional Chilean soccer players before training, which may negatively affect athlete's performance and may increase their risk of heat-related injuries. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

Effects of Different Combinations of Strength, Power, and Plyometric Training on the Physical Performance of Elite Young Soccer Players.

PubMed

Kobal, Ronaldo; Loturco, Irineu; Barroso, Renato; Gil, Saulo; Cuniyochi, Rogério; Ugrinowitsch, Carlos; Roschel, Hamilton; Tricoli, Valmor

2017-06-01

The combination of strength (ST) and plyometric training (PT) has been shown to be effective for improving sport-specific performance. However, there is no consensus about the most effective way to combine these methods in the same training session to produce greater improvements in neuromuscular performance of soccer players. Thus, the purpose of this study was to compare the effects of different combinations of ST and PT sequences on strength, jump, speed, and agility capacities of elite young soccer players. Twenty-seven soccer players (age: 18.9 ± 0.6 years) participated in an 8-week resistance training program and were divided into 3 groups: complex training (CP) (ST before PT), traditional training (TD) (PT before ST), and contrast training (CT) (ST and PT performed alternately, set by set). The experimental design took place during the competitive period of the season. The ST composed of half-squat exercises performed at 60-80% of 1 repetition maximum (1RM); the PT composed of drop jump exercises executed in a range from 30 to 45 cm. After the experimental period, the maximum dynamic strength (half-squat 1RM) and vertical jump ability (countermovement jump height) increased similarly and significantly in the CP, TD, and CT (48.6, 46.3, and 53% and 13, 14.2, and 14.7%, respectively). Importantly, whereas the TD group presented a significant decrease in sprinting speed in 10 (7%) and 20 m (6%), the other groups did not show this response. Furthermore, no significant alterations were observed in agility performance in any experimental group. In conclusion, in young soccer players, different combinations and sequences of ST and PT sets result in similar performance improvements in muscle strength and jump ability. However, it is suggested that the use of the CP and CT methods is more indicated to maintain/maximize the sprint performance of these athletes.

The effect of a novel movement strategy in decreasing ACL risk factors in female adolescent soccer players

PubMed Central

Celebrini, Richard G.; Eng, Janice J.; Miller, William C.; Ekegren, Christina L.; Johnston, James D.; MacIntyre, Donna L.

2015-01-01

There is a need to investigate the effect of specific movement strategies in reducing biomechanical risk factors for ACL injury in young female athletes. The purpose of this study was 1) to determine the feasibility of implementing a novel movement strategy (Core-PAC) into a team warm-up prior to soccer training based on subject compliance and integration of the Core-PAC into the warm-up and 2) to determine whether the Core-PAC would improve peak knee flexion angles and peak abduction moments at the knee during a side-cut (SC) and an unanticipated side-cut (USC) prior to kicking a soccer ball, and a side-hop (SH) task after immediate instruction and after a four-week training program. A convenience sample of ten 14–16 year old female soccer players were instructed in the Core-PAC immediately after baseline testing and during a training program consisting of a 20-minute warm-up, two-times per week. The Core-PAC was understood and accepted by the subjects and incorporated into their warm-up activities with good compliance. After the immediate instruction, there were significant increases in peak knee flexion angles of a mean 6.4° during the SC (p = 0.001), 3.5° during the USC (p = 0.007), and 5.8° during the SH (p < 0.001) tasks. Peak knee abduction moments decreased by a mean of 0.25 Nm/kg during the SC (p < 0.03), 0.17 Nm/kg during the USC (p = 0.05), and 0.27 Nm/kg during the SH (p = 0.04) tasks. After the 4-week training program, some individuals showed improvement. The results of this study suggest that the Core-PAC may be one method of modifying high-risk movements for ACL injury such as side-cutting and single-leg landing. PMID:22210470

Soccer practice as an add-on treatment in the management of individuals with a diagnosis of schizophrenia

PubMed Central

Battaglia, Giuseppe; Alesi, Marianna; Inguglia, Michele; Roccella, Michele; Caramazza, Giovanni; Bellafiore, Marianna; Palma, Antonio

2013-01-01

Physical activity is an important aspect of good health for everyone; it is even more important for psychiatric patients who usually live an unhealthy lifestyle. In recent years, there has been growing focus on the use of soccer as a vehicle to improve the health of subjects with severe mental illness. The aim of this study was to investigate the effects of soccer practice on the self-reported health quality of life (SRHQL) and sports performance (SP) in psychotic subjects. Eighteen male patients with diagnosis of schizophrenia were randomized into either a trained (TG) or a control group (CG). The TG was trained for 12 weeks using two soccer training sessions per week. The CG did not perform any regular sports activity during the experimental period. Anthropometric measurements, SRHQL, personal time records in a 30 meter sprint test and slalom test running with a ball were evaluated before and after the experimental period. SRHQL was assessed using Short Form-12 questionnaire measuring physical and mental component summary scores. After the training period, the TG showed a relevant decrease by 4.6% in bodyweight (BW) and body mass index compared to baseline. Conversely, the CG showed an increased BW and body mass index by 1.8% from baseline to posttest. Moreover, after 12 weeks we found that control patients increased their BW significantly when compared to trained patients (Δ = 5.4%; P < 0.05). After the training period, comparing the baseline TG’s Short Form-12-scores to posttest results, we found an improvement of 10.5% and 10.8% in physical component summary and mental component summary, respectively. In addition, performances on the 30 meter sprint test and slalom test running with a ball in the TG improved significantly (P < 0.01) from baseline to posttest when compared to CG. Soccer practice appears able to improve psychophysical health in individuals with diagnosis of schizophrenia. Indeed, our study demonstrated that programmed soccer physical activity could reduce antipsychotic medication-related weight gain and improve SRHQL and sports performance in psychotic subjects. PMID:23662058

Effects of Unloaded vs. Loaded Plyometrics on Speed and Power Performance of Elite Young Soccer Players.

PubMed

Kobal, Ronaldo; Pereira, Lucas A; Zanetti, Vinicius; Ramirez-Campillo, Rodrigo; Loturco, Irineu

2017-01-01

The purpose of this study was to investigate the effects of loaded and unloaded plyometric training strategies on speed and power performance of elite young soccer players. Twenty-three under-17 male soccer players (age: 15.9 ± 1.2 years, height: 178.3 ± 8.1 cm, body-mass (BM): 68.1 ± 9.3 kg) from the same club took part in this study. The athletes were pair-matched in two training groups: loaded vertical and horizontal jumps using an haltere type handheld with a load of 8% of the athletes' body mass (LJ; n = 12) and unloaded vertical and horizontal plyometrics (UJ; n = 11). Sprinting speeds at 5-, 10-, and 20-m, mean propulsive power (MPP) relative to the players' BM in the jump squat exercise, and performance in the squat jump (SJ) and countermovement jump (CMJ) were assessed pre- and post-training period. During the experimental period, soccer players performed 12 plyometric training sessions across a 6-week preseason period. Magnitude based inferences and standardized differences were used for statistical analysis. A very likely increase in the vertical jumps was observed for the LJ group (99/01/00 and 98/02/00 for SJ and CMJ, respectively). In the UJ group a likely increase was observed for both vertical jumps (83/16/01 and 90/10/00, for SJ and CMJ, respectively). An almost certainly decrease in the sprinting velocities along the 20-m course were found in the LJ group (00/00/100 for all split distances tested). Meanwhile, in the UJ likely to very likely decreases were observed for all sprinting velocities tested (03/18/79, 01/13/86, and 00/04/96, for velocities in 5-, 10-, and 20-m, respectively). No meaningful differences were observed for the MPP in either training group (11/85/04 and 37/55/08 for LJ and UJ, respectively). In summary, under-17 professional soccer players increased jumping ability after a 6-week preseason training program, using loaded or unloaded jumps. Despite these positive adaptations, both plyometric strategies failed to produce worthwhile improvements in maximal speed and power performances, which is possible related to the interference of concurrent training effects. New training strategies should be developed to ensure adequate balance between power and endurance loads throughout short (and high-volume) soccer preseasons.

Effect of Combined Sensorimotor-Resistance Training on Strength, Balance, and Jumping Performance of Soccer Players.

PubMed

Manolopoulos, Konstantinos; Gissis, Ioannis; Galazoulas, Christos; Manolopoulos, Evaggelos; Patikas, Dimitrios; Gollhofer, Albert; Kotzamanidis, Christos

2016-01-01

The purpose of the study was to investigate the effects of resistance training (RT) and sensorimotor training combined with RT (SM-RT) on balance, 1 repetition maximum (RM), rate of force development (RFD), and squat jump (SJ) height. Twenty amateur soccer players were equally divided into 2 groups assigned as SM-RT group (age: 22 ± 1.7 years, body mass: 79.9 ± 6.3 kg, body height: 1.81 ± 0.06 m) and RT group (age: 21.3 ± 1.3 years, body mass: 77.4 ± 9.3 kg, body height: 1.78 ± 0.04 m). Both groups were trained over a 6-week period with 2 session units per week. SM-RT group performed sensorimotor training (balance on balance board) followed by a high-intensity RT at 8-5RM leg press. The RT group performed the resistance program only. Both groups showed significantly increased 1RM leg press strength, RFD, SJ height, and balance abilities (p ≤ 0.05), whereas no significant between-group differences were observed in any of the outcome variables (p > 0.05). It was concluded that SM-RT was not superior compared with RT for both balance and strength enhancement. These findings have implications in time management during training for soccer players.

The effects of neuromuscular training on knee joint motor control during sidecutting in female elite soccer and handball players.

PubMed

Zebis, Mette K; Bencke, Jesper; Andersen, Lars L; Døssing, Simon; Alkjaer, Tine; Magnusson, S Peter; Kjaer, Michael; Aagaard, Per

2008-07-01

The project aimed to implement neuromuscular training during a full soccer and handball league season and to experimentally analyze the neuromuscular adaptation mechanisms elicited by this training during a standardized sidecutting maneuver known to be associated with non-contact anterior cruciate ligament (ACL) injury. The players were tested before and after 1 season without implementation of the prophylactic training and subsequently before and after a full season with the implementation of prophylactic training. A total of 12 female elite soccer players and 8 female elite team handball players aged 26 +/- 3 years at the start of the study. The subjects participated in a specific neuromuscular training program previously shown to reduce non-contact ACL injury. Neuromuscular activity at the knee joint, joint angles at the hip and knee, and ground reaction forces were recorded during a sidecutting maneuver. Neuromuscular activity in the prelanding phase was obtained 10 and 50 ms before foot strike on a force plate and at 10 and 50 ms after foot strike on a force plate. Neuromuscular training markedly increased before activity and landing activity electromyography (EMG) of the semitendinosus (P < 0.05), while quadriceps EMG activity remained unchanged. Neuromuscular training increased EMG activity for the medial hamstring muscles, thereby decreasing the risk of dynamic valgus. This observed neuromuscular adaptation during sidecutting could potentially reduce the risk for non-contact ACL injury.

Neuromuscular Training Availability and Efficacy in Preventing Anterior Cruciate Ligament Injury in High School Sports: A Retrospective Cohort Study.

PubMed

Murray, Jared J; Renier, Colleen M; Ahern, Jenny J; Elliott, Barbara A

2017-11-01

To document neuromuscular training (NMT) availability and its relationship to anterior cruciate ligament (ACL) injuries in 4 major high school sports by gender, sport, and rural/urban geography, with the hypothesis that increased exposure to NMT would be associated with fewer ACL injuries. A retrospective cohort study. All Minnesota high schools identified in the Minnesota State High School League (MSHSL) database for fall 2014 boys' football and soccer, and girls' volleyball and soccer. All high school athletic directors were surveyed to report their school's fall 2014 experience; 53.5% returned the survey reporting experience with one or more of the sports. Athletic directors documented each sport's preseason and in-season exposure to NMT (plyometric exercises, proximal/core muscle strengthening, education and feedback regarding proper body mechanics, and aerobics) and licensed athletic trainers. Reported ACL injuries by sport, gender and rural/urban. More than two-thirds of teams incorporated facets of NMT into their sport. Among male athletes, soccer players exposed to licensed athletic trainers experienced significantly fewer ACL injuries (P < 0.005), and NMT was associated with significantly fewer ACL injuries in football (P < 0.05) and soccer (P < 0.05). Female athletes did not demonstrate similar associated improvements, with volleyball injuries associated with increased NMT (P < 0.001), and soccer injuries not associated with NMT. However, girl soccer players in rural settings reported fewer ACL injures compared with urban teams (P < 0.001). Most fall high school sports teams were exposed to NMT, which was associated with fewer ACL injuries for male, but not for female athletes. Improved gender- and sport-specific preventive training programs are indicated.

Effects of a high-intensity intermittent training program on aerobic capacity and lipid profile in trained subjects

PubMed Central

Ouerghi, Nejmeddine; Khammassi, Marwa; Boukorraa, Sami; Feki, Moncef; Kaabachi, Naziha; Bouassida, Anissa

2014-01-01

Background Data regarding the effect of training on plasma lipids are controversial. Most studies have addressed continuous or long intermittent training programs. The present study evaluated the effect of short-short high-intensity intermittent training (HIIT) on aerobic capacity and plasma lipids in soccer players. Methods The study included 24 male subjects aged 21–26 years, divided into three groups: experimental group 1 (EG1, n=8) comprising soccer players who exercised in addition to regular short-short HIIT twice a week for 12 weeks; experimental group 2 (EG2, n=8) comprising soccer players who exercised in a regular football training program; and a control group (CG, n=8) comprising untrained subjects who did not practice regular physical activity. Maximal aerobic velocity and maximal oxygen uptake along with plasma lipids were measured before and after 6 weeks and 12 weeks of the respective training program. Results Compared with basal values, maximal oxygen uptake had significantly increased in EG1 (from 53.3±4.0 mL/min/kg to 54.8±3.0 mL/min/kg at 6 weeks [P<0.05] and to 57.0±3.2 mL/min/kg at 12 weeks [P<0.001]). Maximal oxygen uptake was increased only after 12 weeks in EG2 (from 52.8±2.7 mL/min/kg to 54.2±2.6 mL/min/kg, [P<0.05]), but remain unchanged in CG. After 12 weeks of training, maximal oxygen uptake was significantly higher in EG1 than in EG2 (P<0.05). During training, no significant changes in plasma lipids occurred. However, after 12 weeks, total and low-density lipoprotein cholesterol levels had decreased (by about 2%) in EG1 but increased in CG. High-density lipoprotein cholesterol levels increased in EG1 and EG2, but decreased in CG. Plasma triglycerides decreased by 8% in EG1 and increased by about 4% in CG. Conclusion Twelve weeks of short-short HIIT improves aerobic capacity. Although changes in the lipid profile were not significant after this training program, they may have a beneficial impact on health. PMID:25378960

Coaching Peripheral Vision Training for Soccer Athletes

ERIC Educational Resources Information Center

Marques, Nelson Kautzner, Jr.

2010-01-01

Brazilian Soccer began developing its current emphasis on peripheral vision in the late 1950s, by initiative of coach of the Canto do Rio Football Club, in Niteroi, Rio de Janeiro, a pioneer in the development of peripheral vision training in soccer players. Peripheral vision training gained world relevance when a young talent from Canto do Rio,…

Effects of the performance level and the FIFA "11" injury prevention program on the injury rate in Italian male amateur soccer players.

PubMed

Gatterer, H; Ruedl, G; Faulhaber, M; Regele, M; Burtscher, M

2012-02-01

Soccer is characterized by high injury rates that necessitate interventions for its reduction. The "11" is a multi-modal preventive program that was developed to reduce injury rate. However, outcomes on the effectiveness of the program are not unambiguous and data for the largest group at risk (i.e., male adult amateur players) are missing. The study aims to assess the injury rate in male adult amateur soccer players of different levels and to evaluate the effectiveness of the prevention program the "11". Three amateur soccer teams participated in the study during the first round of a competition season. Two teams played at a regional level (6th Italian league) and one team at a provincial level (7th Italian league). The regional league is of a higher skill level compared to the provincial league. Duration and frequency of training and match sessions and the occurrence of time-loss injuries were recorded. One team of the 6th league performed an injury prevention program. The total injury rate for the intervention and the control team in the 6th league was 3.3 (CI 0.7-5.9) and 4.3 (CI 1.3-7.3) injuries/1000 h, respectively (P=0.841). The 6th league control team tended to have a lesser injury rate compared to the 7th league team (P=0.081). The relative risk was 2 fold higher in the 7th compared to the 6th league team (P=0.0285 one tailed). Present results show that injury rate in amateur soccer depended rather on the skill level than the prevention program. In this study the prevention program the "11" was not shown to be highly effective in soccer player of intermediate level (i.e., 6th Italian league).

A retrospective study on anthropometrical, physical fitness, and motor coordination characteristics that influence dropout, contract status, and first-team playing time in high-level soccer players aged eight to eighteen years.

PubMed

Deprez, Dieter N; Fransen, Job; Lenoir, Matthieu; Philippaerts, Renaat M; Vaeyens, Roel

2015-06-01

The goal of this article was twofold, and a 2-study approach was conducted. The first study aimed to expose the anthropometrical, physical performance, and motor coordination characteristics that influence dropout from a high-level soccer training program in players aged 8-16 years. The mixed-longitudinal sample included 388 Belgian youth soccer players who were assigned to either a "club group" or a "dropout group." In the second study, cross-sectional data of anthropometry, physical performance, and motor coordination were retrospectively explored to investigate which characteristics influence future contract status (contract vs. no contract group) and first-team playing time for 72 high-level youth soccer players (mean age = 16.2 years). Generally, club players outperformed their dropout peers for motor coordination, soccer-specific aerobic endurance, and speed. Anthropometry and estimated maturity status did not discriminate between club and dropout players. Contract players jumped further (p = 0.011) and had faster times for a 5-m sprint (p = 0.041) than no contract players. The following prediction equation explains 16.7% of the variance in future playing minutes in adolescent youth male soccer players: -2,869.3 + 14.6 × standing broad jump. Practitioners should include the evaluation of motor coordination, aerobic endurance, and speed performances to distinguish high-level soccer players further succeeding a talent development program and future dropout players, between 8 and 16 years. From the age of 16 years, measures of explosivity are supportive when selecting players into a future professional soccer career.

Does eccentric training of hamstring muscles reduce acute injuries in soccer?

PubMed

Nichols, Andrew W

2013-01-01

To investigate the effectiveness of a 10-week hamstring exercise training program in reducing the incidence and severity of new and recurrent hamstring injuries among male soccer players. Cluster-randomized (by team)controlled trial, stratified by level of play and geographic location. Sample size was calculated with 80% power to show a relative risk reduction for injury of 50% at P ≤ 0.05. Soccer community study in Denmark during the period January to December 2008. Teams in the top 5 soccer divisions (2 professional and 3 amateur)were invited to participate. The exclusion criterion for teams was that they already used eccentric hamstring exercises, and for participants was that they joined the teams after the beginning of the season. Of 116 teams, 54 were eligible and willing to be randomized and 50 were included in the analysis (942 players). Teams in both the intervention and control groups followed their normal training programs. At the beginning of the study period, the intervention teams added 27 sessions of the Nordicham string exercise (after warm-up) during the 10-week period of the mid-season break. The exercise begins with the player kneeling with the torso upright and rigid, and the feet held down to the ground by a partner. The player lowers his torso forwards toward the ground braking with his hamstring muscles until the chest reaches the ground (eccentric phase). He returns to the upright position, pushing with his hands to minimize the concentric phase load. Sessions per week and sets and repetitions per session increased to 3, 3, and 12, respectively. Team coaches supervised the sessions. A hamstring injury was defined as an acute occurrence of a “physical complaint in the region of the posterior thigh sustained during a soccer match or training, irrespective of the need for medical attention or time loss from soccer activities.” Injuries were recorded by the teams’ medical staff on standardized forms. Only first injuries during the season were included and recorded as first-time injuries or recurrences of injuries sustained before the season.Severity of injury was defined by number of days lost from full participation in games and practices. Injury rates per 100 player sessions were lower for the intervention group (3.8) than for the control group(13.1); thus, the rate ratio (RR) adjusted for age, level of competition, and previous injury was 0.293 (95% confidence interval[CI], 0.150-0.572). Both rates of new and recurrent injuries were lower for the intervention group than for the control group(new injuries: RR, 0.410; 95% CI, 0.180-0.933; recurrent injuries: RR, 0.137; 95% CI, 0.037-0.509). The 15 injuries in the intervention group resulted in absence of 454 days from soccer (mean, 30.3; SD, 18.3; range, 7-64 days per injury), whereas 51 injuries in the control group resulted in 1344 days absent (mean, 26.4; SD, 19.5; range, 4-89 days per injury). Mean severity of injuries (days absent) was not significantly different (P = 0.16) between groups. Delayed onset muscle soreness,but no other adverse effect, was reported by most members of the intervention group during the training period. An eccentric hamstring exercise program was associated with lower rates of new and recurrent hamstring injuries in Danish male soccer players.

The Effects of Injury Preventive Warm-Up Programs on Knee Strength Ratio in Young Male Professional Soccer Players

PubMed Central

Daneshjoo, Abdolhamid; Mokhtar, Abdul Halim; Rahnama, Nader; Yusof, Ashril

2012-01-01

Purpose We aimed to investigate the effect of FIFA 11+ (11+) and HarmoKnee injury preventive warm-up programs on conventional strength ratio (CSR), dynamic control ratio (DCR) and fast/slow speed ratio (FSR) in young male professional soccer players. These ratios are related to the risk of injury to the knee in soccer players. Methods Thirty-six players were divided into 3 groups; FIFA 11+, HarmoKnee and control (n = 12 per group). These exercises were performed 3 times per week for 2 months (24 sessions). The CSR, DCR and FSR were measured before and after the intervention. Results After training, the CSR and DCR of knee muscles in both groups were found to be lower than the published normal values (0.61, 0.72, and 0.78 during 60°.s−1, 180°.s−1 and 300°.s−1, respectively). The CSR (60°.s−1) increased by 8% and FSR in the quadriceps of the non-dominant leg by 8% in the 11+. Meanwhile, the DCR in the dominant and non-dominant legs were reduced by 40% and 30% respectively in the 11+. The CSR (60°.s−1) in the non-dominant leg showed significant differences between the 11+, HarmoKnee and control groups (p = 0.02). As for the DCR analysis between groups, there were significant differences in the non-dominant leg between both programs with the control group (p = 0.04). For FSR no significant changes were found between groups. Conclusions It can be concluded that the 11+ improved CSR and FSR, but the HarmoKnee program did not demonstrate improvement. We suggest adding more training elements to the HarmoKnee program that aimed to enhance hamstring strength (CSR, DCR and FSR). Professional soccer players have higher predisposition of getting knee injuries because hamstring to quadriceps ratio were found to be lower than the average values. It seems that the 11+ have potentials to improve CSR and FSR as well as prevent knee injuries in soccer players. PMID:23226553

The effects of resisted sprint training on acceleration performance and kinematics in soccer, rugby union, and Australian football players.

PubMed

Spinks, Christopher D; Murphy, Aron J; Spinks, Warwick L; Lockie, Robert G

2007-02-01

Acceleration is a significant feature of game-deciding situations in the various codes of football. However little is known about the acceleration characteristics of football players, the effects of acceleration training, or the effectiveness of different training modalities. This study examined the effects of resisted sprint (RS) training (weighted sled towing) on acceleration performance (0-15 m), leg power (countermovement jump [CMJ], 5-bound test [5BT], and 50-cm drop jump [50DJ]), gait (foot contact time, stride length, stride frequency, step length, and flight time), and joint (shoulder, elbow, hip, and knee) kinematics in men (N = 30) currently playing soccer, rugby union, or Australian football. Gait and kinematic measurements were derived from the first and second strides of an acceleration effort. Participants were randomly assigned to 1 of 3 treatment conditions: (a) 8-week sprint training of two 1-h sessions x wk(-1) plus RS training (RS group, n = 10), (b) 8-week nonresisted sprint training program of two 1-h sessions x wk(-1) (NRS group, n = 10), or (c) control (n = 10). The results indicated that an 8-week RS training program (a) significantly improves acceleration and leg power (CMJ and 5BT) performance but is no more effective than an 8-week NRS training program, (b) significantly improves reactive strength (50DJ), and (c) has minimal impact on gait and upper- and lower-body kinematics during acceleration performance compared to an 8-week NRS training program. These findings suggest that RS training will not adversely affect acceleration kinematics and gait. Although apparently no more effective than NRS training, this training modality provides an overload stimulus to acceleration mechanics and recruitment of the hip and knee extensors, resulting in greater application of horizontal power.

Initial Weekly HRV Response is Related to the Prospective Change in VO2max in Female Soccer Players.

PubMed

Esco, M R; Flatt, A A; Nakamura, F Y

2016-06-01

The aim of this study was to determine whether the early response in weekly measures of HRV, when derived from a smartphone application, were related to the eventual change in VO2max following an off-season training program in female soccer athletes. 9 female collegiate soccer players participated in an 11-week off-season conditioning program. In the week immediately before and after the training program, each participant performed a test on a treadmill to determine maximal oxygen consumption (VO2max). Daily measures of the log-transformed root mean square of successive R-R intervals (lnRMSSD) were performed by the participants throughout week 1 and week 3 of the conditioning program. The mean and coefficient of variation (CV) lnRMSSD values of week 1 showed small (r=- 0.13, p=0.74) and moderate (r=0.57, p=0.11), respectively, non-significant correlations to the change in VO2max at the end of the conditioning program (∆VO2max). Significant and near-perfect correlation was found between the change in the weekly mean lnRMSSD values from weeks 1 and 3 (∆lnRMSSDM) and ∆VO2max (r=0.90, p=0.002). The current results have identified that the initial change in weekly mean lnRMSSD from weeks 1 to 3 of a conditioning protocol was strongly associated with the eventual adaptation of VO2max. © Georg Thieme Verlag KG Stuttgart · New York.

Switching between pitch surfaces: practical applications and future perspectives for soccer training.

PubMed

Rago, Vincenzo; Silva, João R; Brito, João; Barreira, Daniel; Mohr, Magni; Krustrup, Peter; Rebelo, António N

2018-04-04

Soccer training and completion is conventionally practiced on natural grass (NG) or artificial turf (AT). Recently, AT pitches for training / competition, and of unstable surfaces for injury prevention training has increased. Therefore, soccer players are frequently exposed to variations in pitch surface during either training or competition. These ground changes may impact physical and physiological responses, adaptations as well as the injury. The aim of this review was to summarize the acute physical and physiological responses, chronic adaptations, and injury risk associated with exercising on different pitch surfaces in soccer. Eligible studies were published in English, had pitch surface as an independent variable, and had physical, physiological or epidemiological information as outcome variables. Specific data extracted from the articles included the training response, training adaptations or injury outcomes according to different pitch surfaces. A total of 224 studies were retrieved from a literature search. Twenty articles met the inclusion criteria: 9 for acute physical and physiological responses, 2 for training adaptations and 9 for injury assessment. The literature lacks consistent evidence regarding the effects of pitch surface on performance and health outcomes in soccer players. However, it seems that occasionally switching training surfaces seems a valuable strategy for focusing on specific musculoskeletal queries and enhancing players' fitness. For instance, sand training may be occasionally proposed as complementary training strategy, given the recruitment of additional musculature probably not involved on firmer surfaces, but the possible training-induced adaptations of non-conventional soccer surfaces (e.g., sand) might potentially result into a negative transfer on AT or NG. Since the specific physical demands of soccer can differ between surfaces, coaches should resort to the use of non-traditional surfaces with parsimony, emphasizing the specific surface-related motor tasks, normally observed on natural grass or artificial turf. Further studies are required to better understand the physiological effects induced by systematic surface-specific training, or switching between pitch surfaces.

Rehabilitation after a grade III latissimus dorsi tear of a soccer player: A case report.

PubMed

Fysentzou, Christodoulos

2016-11-21

Latissimus dorsi, grade III tendon tears are an uncommon injury. There are very few cases reported in the literature, but most importantly, no cases could be found that relate to soccer. To present a successful, non-operative rehabilitation program for a professional athlete, after a grade III latissimus dorsi tear. A 37 year old healthy, elite professional soccer goalkeeper was injured during a championship game. The athlete fell on his left side with an outstretched and externally rotated upper extremity in order to catch a ball that was going very close to the left pole of his goal-post. After on-field and off-field clinical examinations, the diagnosis was a left latissimus dorsi tendon tear which was later confirmed by MRI as a grade III tear. During the first two weeks, intervention consisted of anti-inflammatory treatment and light therapeutic exercises. As the pain was subsiding and the strength was returning, the treatment shifted to purely strengthening and functional training. Four weeks after the injury, the athlete presented with pain 0/10 in all functional activities and full ROM in both active and passive movements. Before discharge, the athlete underwent a sport specific training program, without any complains, that cleared him to participate in normal training with the rest of the team. Three months after the injury the strength of the player's left shoulder was 5/5 in all movements. The protocol used yielded an accelerated return to sport (soccer) and function compared with other published research after a grade III latissimus dorsi tendon tear. One year later, the goalkeeper was still playing in the same competitive level without any re-injuries or complains, which means that this treatment protocol withstood the test of time.

Effects of High-Velocity Resistance Training on Athletic Performance in Prepuberal Male Soccer Athletes.

PubMed

Negra, Yassine; Chaabene, Helmi; Hammami, Mehréz; Hachana, Younés; Granacher, Urs

2016-12-01

Negra, Y, Chaabene, H, Hammami, M, Hachana, Y, and Granacher, U. Effects of high-velocity resistance training on athletic performance in prepuberal male soccer athletes. J Strength Cond Res 30(12): 3290-3297, 2016-The aim of this study was to assess the effectiveness of a 12-week in-season low-to-moderate load high-velocity resistance training (HVRT) in addition to soccer training as compared with soccer training only on proxies of athletic performance in prepubertal soccer players. Twenty-four male soccer players performed 2 different protocols: (a) regular soccer training with 5 sessions per week (n = 11; age = 12.7 ± 0.3 years) and (b) regular soccer training with 3 sessions per week and HVRT with 2 sessions per week (n = 13; age = 12.8 ± 0.2 years). The outcome measures included tests for the assessment of muscle strength (e.g., 1 repetition maximum [1RM] half-squat tests), jump ability (e.g., countermovement jump, squat jump [SJ], standing long jump [SLJ], and multiple 5-bound tests [MB5s]), linear speed (e.g., 5-, 10-, 20-, and 30-m sprint tests), and change of direction (e.g., T-test and Illinois change of direction test). Results revealed significant group × test interactions for the SJ test (p ≤ 0.05, d = 0.59) and the SLJ test (p < 0.01, d = 0.83). Post hoc tests illustrated significant pre-post changes in the HVRT group (SJ: [INCREMENT]22%, p < 0.001, d = 1.26; SLJ: [INCREMENT]15%, p < 0.001, d = 1.30) but not in the control group. In addition, tendencies toward significant interaction effects were found for the 1RM half-squat (p = 0.08, d = 0.54) and the 10-m sprint test (p = 0.06, d = 0.57). Significant pre-post changes were found for both parameters in the HVRT group only (1RM: [INCREMENT]25%, p < 0.001, d = 1.23; 10-m sprint: [INCREMENT]7%, p < 0.0001, d = 1.47). In summary, in-season low-to-moderate load HVRT conducted in combination with regular soccer training is a safe and feasible intervention that has positive effects on maximal strength, vertical and horizontal jump and sprint performance as compared with soccer training only.

Brain-Behavior Mechanisms for the Transfer of Neuromuscular Training Adaptions to Simulated Sport: Initial Findings from the Train the Brain Project.

PubMed

Grooms, Dustin R; Kiefer, Adam W; Riley, Michael A; Ellis, Jonathan D; Thomas, Staci; Kitchen, Katie; DiCesare, Christopher; Bonnette, Scott; Gadd, Brooke; Barber Foss, Kim D; Yuan, Weihong; Silva, Paula; Galloway, Ryan; Diekfuss, Jed; Leach, James; Berz, Kate; Myer, Gregory D

2018-03-27

A limiting factor for reducing anterior cruciate ligament (ACL) injury risk is ensuring that the movement adaptions made during the prevention program transfer to sport-specific activity. Virtual reality provides a mechanism to assess transferability and neuroimaging provides a means to assay the neural processes allowing for such skill transfer. To determine the neural mechanisms for injury risk reducing biomechanics transfer to sport after ACL injury prevention training. Cohort study Setting: Research laboratory Participants: Four healthy high school soccer athletes. Participants completed augmented neuromuscular training utilizing real-time visual feedback. An unloaded knee extension task and a loaded leg-press task was completed with neuroimaging before and after training. A virtual reality soccer specific landing task was also competed following training to assess transfer of movement mechanics. Landing mechanics during the virtual reality soccer task and blood oxygen level dependent signal change during neuroimaging. Increased motor planning, sensory and visual region activity during unloaded knee extension and decreased motor cortex activity during loaded leg-press were highly correlated with improvements in landing mechanics (decreased hip adduction and knee rotation). Changes in brain activity may underlie adaptation and transfer of injury risk reducing movement mechanics to sport activity. Clinicians may be able to target these specific brain processes with adjunctive therapy to facilitate intervention improvements transferring to sport.

High-Intensity Small-Sided Games versus Repeated Sprint Training in Junior Soccer Players.

PubMed

Eniseler, Niyazi; Şahan, Çağatay; Özcan, Ilker; Dinler, Kıvanç

2017-12-01

The aim of this study was to compare the effects of high-intensity small-sided games training (SSGT) versus repeated-sprint training (RST) on repeated-sprint ability (RSA), soccer specific endurance performance and short passing ability among junior soccer players. The junior soccer players were recruited from of a professional team (age 16.9 ± 1.1 years). The tests included the repeated-shuttle-sprint ability test (RSSAT), Yo-Yo Intermittent Recovery Test level 1 (Yo-Yo IR1) and Loughborough Soccer Passing Test (LSPT). Nineteen participants were randomly assigned to either the small-sided games training (SSGTG) (n = 10) or repeated-sprint training group (RSTG) (n = 9). Small-sided games or repeated-sprint training were added to the regular training sessions for two days of the regular practice week. The Wilcoxon signed-rank and Mann-Whitney U tests were used to examine differences in groups and training effects. A time x training group effect was found in the improvement of short-passing ability for the smallsided games training group which showed significantly better scores than the repeated-sprint training group (p ≤ 0.05). Both groups showed similar improvements in RSAdecrement (p < 0.05). Only the repeated-sprint training group improved in the Yo-Yo IR1 (p < 0.05). This study clearly shows that high-intensity small-sided games training can be used as an effective training mode to enhance both repeated sprint ability and short-passing ability.

High-Intensity Small-Sided Games versus Repeated Sprint Training in Junior Soccer Players

PubMed Central

Şahan, Çağatay; Özcan, Ilker; Dinler, Kıvanç

2017-01-01

Abstract The aim of this study was to compare the effects of high-intensity small-sided games training (SSGT) versus repeated-sprint training (RST) on repeated-sprint ability (RSA), soccer specific endurance performance and short passing ability among junior soccer players. The junior soccer players were recruited from of a professional team (age 16.9 ± 1.1 years). The tests included the repeated-shuttle-sprint ability test (RSSAT), Yo-Yo Intermittent Recovery Test level 1 (Yo-Yo IR1) and Loughborough Soccer Passing Test (LSPT). Nineteen participants were randomly assigned to either the small-sided games training (SSGTG) (n = 10) or repeated-sprint training group (RSTG) (n = 9). Small-sided games or repeated-sprint training were added to the regular training sessions for two days of the regular practice week. The Wilcoxon signed-rank and Mann-Whitney U tests were used to examine differences in groups and training effects. A time x training group effect was found in the improvement of short-passing ability for the smallsided games training group which showed significantly better scores than the repeated-sprint training group (p ≤ 0.05). Both groups showed similar improvements in RSAdecrement (p < 0.05). Only the repeated-sprint training group improved in the Yo-Yo IR1 (p < 0.05). This study clearly shows that high-intensity small-sided games training can be used as an effective training mode to enhance both repeated sprint ability and short-passing ability. PMID:29339990

Effect of 8 Weeks Soccer Training on Health and Physical Performance in Untrained Women

PubMed Central

Ortiz, Jaelson G.; da Silva, Juliano F.; Carminatti, Lorival J.; Guglielmo, Luiz G.A.; Diefenthaeler, Fernando

2018-01-01

This study aims to analyze the physiological, neuromuscular, and biochemical responses in untrained women after eight weeks of regular participation in small-sided soccer games compared to aerobic training. Twenty-seven healthy untrained women were divided into two groups [soccer group (SG = 17) and running group (RG = 10)]. Both groups trained three times per week for eight weeks. The variables measured in this study were maximal oxygen uptake (VO2max), relative velocity at VO2max (vVO2max), peak velocity, relative intensity at lactate threshold (vLT), relative intensity at onset of blood lactate accumulation (vOBLA), peak force, total cholesterol, HDL, LDL, triglycerides, and cholesterol ratio (LDL/HDL). VO2max, vLT, and vOBLA increased significantly in both groups (12.8 and 16.7%, 11.1 and 15.3%, 11.6 and 19.8%, in SG and RG respectively). However, knee extensors peak isometric strength and triglyceride levels, total cholesterol, LDL, and HDL did not differ after eight weeks of training in both groups. On the other hand, the LDL/HDL ratio significantly reduced in both groups. In conclusion, eight weeks of regular participation in small-sided soccer games was sufficient to increase aerobic performance and promote health benefits related to similar aerobic training in untrained adult women. Key points Regular participation in soccer small sided-games increase aerobic performance and promote health benefits related to similar aerobic training in untrained women. 8 weeks soccer training is enough to promote positive physiological and biochemical adaptations in untrained women. Soccer small sided-games have the potential to be more pleasurable and effective among women as other modalities as running and cycling. PMID:29535574

Combination of Recreational Soccer and Caloric Restricted Diet Reduces Markers of Protein Catabolism and Cardiovascular Risk in Patients with Type 2 Diabetes.

PubMed

Vieira de Sousa, M; Fukui, R; Krustrup, P; Dagogo-Jack, S; Rossi da Silva, M E

2017-01-01

Moderate calorie-restricted diets and exercise training prevent loss of lean mass and cardiovascular risk. Because adherence to routine exercise recommendation is generally poor, we utilized recreational soccer training as a novel therapeutic exercise intervention in type 2 diabetes (T2D) patients. We compared the effects of acute and chronic soccer training plus calorie-restricted diet on protein catabolism and cardiovascular risk markers in T2D. Fifty-one T2D patients (61.1±6.4 years, 29 females: 22 males) were randomly allocated to the soccer+diet-group (SDG) or to the diet-group (DG). The 40-min soccer sessions were held 3 times per week for 12 weeks. Nineteen participants attended 100% of scheduled soccer sessions, and none suffered any injuries. The SDG group showed higher levels of growth hormone (GH), free fatty acids and ammonia compared with DG. After 12 weeks, insulin-like growth factor binding protein (IGFPB)-3 and glucose levels were lower in SDG, whereas insulin-like growth factor (IGF)-1/ IGFBP-3 ratio increased in both groups. After the last training session, an increase in IGF-1/IGFBP-3 and attenuation in ammonia levels were suggestive of lower muscle protein catabolism. Recreational soccer training was popular and safe, and was associated with decreased plasma glucose and IGFBP-3 levels, decreased ammoniagenesis, and increased lipolytic activity and IGF-1/IGFBP-3 ratio, all indicative of attenuated catabolism.

Lactate threshold responses to a season of professional British youth soccer

PubMed Central

McMillan, K; Helgerud, J; Grant, S; Newell, J; Wilson, J; Macdonald, R; Hoff, J

2005-01-01

Objective: To examine the changes in aerobic endurance performance of professional youth soccer players throughout the soccer season. Methods: Nine youth soccer players were tested at six different time points throughout the soccer season by sub-maximal blood lactate assessment, using an incremental treadmill protocol. Whole blood lactate concentration and heart frequency (Hf) were determined at each exercise stage. Running velocities at the first lactate inflection point (v-Tlac) and at a blood lactate concentration of 4 mmol l–1 (v-4mM) were determined. Results: Running velocity at the two lactate thresholds increased from the start of pre-season training to the early weeks of the competitive season, from 11.67 (0.29) to 12.96 (0.28) km h–1 for v-Tlac, and from 13.62 (0.25) to 14.67 (0.24) km h–1 for v-4mM (p<0.001). However, v-Tlac and v-4mM when expressed relative to maximum heart frequency (Hfmax) remained unchanged. The Hf to blood lactate concentration relationship was unchanged after the pre-season training period. The two expressions of lactate threshold did not reveal differences between each other. Conclusion: Running velocity at v-Tlac and v-4mM increased significantly over the pre-season period, but v-Tlac and v-4mM were unchanged when expressed relative to Hfmax. This finding may indicate that increased endurance performance may be mainly attributable to alterations in Vo2max. Although lactate assessment of soccer players is useful for determining endurance training adaptations in soccer players, additional assessment of the other two determinants of endurance performance (Vo2max and running economy) may provide more useful information for determining physiological adaptations resulting from soccer training and training interventions. PMID:15976165

Endurance training in patients with schizophrenia and healthy controls: differences and similarities.

PubMed

Keller-Varady, Katriona; Hasan, Alkomiet; Schneider-Axmann, Thomas; Hillmer-Vogel, Ursula; Adomßent, Björn; Wobrock, Thomas; Schmitt, Andrea; Niklas, Andree; Falkai, Peter; Malchow, Berend

2016-08-01

The aims were to examine the feasibility of and adaptations to endurance training in persons diagnosed with schizophrenia and to address the question whether the principles and beneficial effects of endurance training established in the healthy population apply also to patients with schizophrenia. In this controlled interventional study, 22 patients with schizophrenia and 22 healthy controls performed a standardized aerobic endurance training on bicycle ergometers over 12 weeks. Another group of 21 patients with schizophrenia played table soccer. Endurance capacity was measured with incremental cycle ergometry before and after the intervention and 3 months later. A specific set of outcome parameters was defined. The training stimuli can be assumed to be similar in both endurance groups. Endurance capacity improved significantly in the endurance groups, but not in the table soccer group. Patients and healthy controls showed comparable adaptations to endurance training, as assessed by physical working capacity and maximal achieved power. Differences were found in changes of performance at a lactate concentration of 3 mmol/l. Endurance training was feasible and effective in both groups. The principles and types of training that are usually applied to healthy controls need to be verified in patients with schizophrenia. Nevertheless, patients benefited from endurance training in terms of improvement of endurance capacity and reduction in the baseline deficit in comparison with healthy controls. Therefore, endurance training should be implemented in future therapy programs. These programs need to pay special attention to the differences between patients with schizophrenia and healthy controls.

Effects of horizontal plyometric training volume on soccer players' performance.

PubMed

Yanci, Javier; Los Arcos, Asier; Camara, Jesús; Castillo, Daniel; García, Alberto; Castagna, Carlo

2016-01-01

The aim of this study was to examine the dose response effect of strength and conditioning programmes, involving horizontally oriented plyometric exercises, on relevant soccer performance variables. Sixteen soccer players were randomly allocated to two 6-week plyometric training groups (G1 and G2) differing by imposed (twice a week) training volume. Post-training G1 (4.13%; d = 0.43) and G2 (2.45%; d = 0.53) moderately improved their horizontal countermovement jump performance. Significant between-group differences (p < 0.01) in the vertical countermovement jump for force production time (T2) were detected post-training. No significant and practical (p > 0.05, d = trivial or small) post-training improvements in sprint, change of direction ability (CODA) and horizontal arm swing countermovement jump were reported in either group. Horizontal plyometric training was effective in promoting improvement in injury prevention variables. Doubling the volume of a horizontal plyometric training protocol was shown to have no additional effect over functional aspects of soccer players' performance.

Hydration Status and Fluid Balance of Elite European Youth Soccer Players during Consecutive Training Sessions.

PubMed

Phillips, Saun M; Sykes, Dave; Gibson, Neil

2014-12-01

The objective of the study was to investigate the hydration status and fluid balance of elite European youth soccer players during three consecutive training sessions. Fourteen males (age 16.9 ± 0.8 years, height 1.79 ± 0.06 m, body mass (BM) 70.6 ± 5.0 kg) had their hydration status assessed from first morning urine samples (baseline) and pre- and post-training using urine specific gravity (USG) measures, and their fluid balance calculated from pre- to post-training BM change, corrected for fluid intake and urine output. Most participants were hypohydrated upon waking (USG >1.020; 77% on days 1 and 3, and 62% on day 2). There was no significant difference between first morning and pre-training USG (p = 0.11) and no influence of training session (p = 0.34) or time (pre- vs. post-training; p = 0.16) on USG. Significant BM loss occurred in sessions 1-3 (0.69 ± 0.22, 0.42 ± 0.25, and 0.38 ± 0.30 kg respectively, p < 0.05). Mean fluid intake in sessions 1-3 was 425 ± 185, 355 ± 161, and 247 ± 157 ml, respectively (p < 0.05). Participants replaced on average 71.3 ± 64.1% (range 0-363.6%) of fluid losses across the three sessions. Body mass loss, fluid intake, and USG measures showed large inter-individual variation. Elite young European soccer players likely wake and present for training hypohydrated, when a USG threshold of 1.020 is applied. When training in a cool environment with ad libitum access to fluid, replacing ~71% of sweat losses results in minimal hypohydration (<1% BM). Consumption of fluid ad libitum throughout training appears to prevent excessive (≥2% BM) dehydration, as advised by current fluid intake guidelines. Current fluid intake guidelines appear applicable for elite European youth soccer players training in a cool environment. Key PointsThe paper demonstrates a notable inter-participant variation in first morning, pre- and post-training hydration status and fluid balance of elite young European soccer players.On average, elite young European soccer players are hypohydrated upon waking and remain hypohydrated before and after training.Elite young European soccer players display varied fluid intake volumes during training, but on average do not consume sufficient fluid to offset fluid losses.Consecutive training sessions do not significantly impair hydration status, suggesting that elite young European soccer players consume sufficient fluid between training to maintain a stable hydration status and prevent excessive (≥2% body mass) dehydrationCurrent fluid intake guidelines appear applicable to this population when training in a cool environment.

Hydration Status and Fluid Balance of Elite European Youth Soccer Players during Consecutive Training Sessions

PubMed Central

Phillips, Saun M.; Sykes, Dave; Gibson, Neil

2014-01-01

The objective of the study was to investigate the hydration status and fluid balance of elite European youth soccer players during three consecutive training sessions. Fourteen males (age 16.9 ± 0.8 years, height 1.79 ± 0.06 m, body mass (BM) 70.6 ± 5.0 kg) had their hydration status assessed from first morning urine samples (baseline) and pre- and post-training using urine specific gravity (USG) measures, and their fluid balance calculated from pre- to post-training BM change, corrected for fluid intake and urine output. Most participants were hypohydrated upon waking (USG >1.020; 77% on days 1 and 3, and 62% on day 2). There was no significant difference between first morning and pre-training USG (p = 0.11) and no influence of training session (p = 0.34) or time (pre- vs. post-training; p = 0.16) on USG. Significant BM loss occurred in sessions 1-3 (0.69 ± 0.22, 0.42 ± 0.25, and 0.38 ± 0.30 kg respectively, p < 0.05). Mean fluid intake in sessions 1-3 was 425 ± 185, 355 ± 161, and 247 ± 157 ml, respectively (p < 0.05). Participants replaced on average 71.3 ± 64.1% (range 0-363.6%) of fluid losses across the three sessions. Body mass loss, fluid intake, and USG measures showed large inter-individual variation. Elite young European soccer players likely wake and present for training hypohydrated, when a USG threshold of 1.020 is applied. When training in a cool environment with ad libitum access to fluid, replacing ~71% of sweat losses results in minimal hypohydration (<1% BM). Consumption of fluid ad libitum throughout training appears to prevent excessive (≥2% BM) dehydration, as advised by current fluid intake guidelines. Current fluid intake guidelines appear applicable for elite European youth soccer players training in a cool environment. Key Points The paper demonstrates a notable inter-participant variation in first morning, pre- and post-training hydration status and fluid balance of elite young European soccer players. On average, elite young European soccer players are hypohydrated upon waking and remain hypohydrated before and after training. Elite young European soccer players display varied fluid intake volumes during training, but on average do not consume sufficient fluid to offset fluid losses. Consecutive training sessions do not significantly impair hydration status, suggesting that elite young European soccer players consume sufficient fluid between training to maintain a stable hydration status and prevent excessive (≥2% body mass) dehydration Current fluid intake guidelines appear applicable to this population when training in a cool environment PMID:25435774

Hormonal (Cortical-Gonadotropic Axis) and Physical Changes With Two Years Intense Exercise Training in Elite Young Soccer Players.

PubMed

Hammami, Mohamed Ali; Ben Abderrahman, Abderraouf; Hackney, Anthony C; Kebsi, Wiem; Owen, Adam L; Nebigh, Amar; Racil, Ghazi; Tabka, Zouhair; Zouhal, Hassane

2017-09-01

Hammami, MA, Ben Abderrahman, A, Hackney, AC, Kebsi, W, Owen, AL, Nebigh, A, Racil, G, Tabka, Z, and Zouhal, H. Hormonal (cortical-gonadotropic axis) and physical changes with two years intense exercise training in elite young soccer players. J Strength Cond Res 31(9): 2388-2397, 2017-The aim of this study was to investigate the effects of 2 soccer-training seasons on physical fitness and hormone concentrations in elite youth soccer players. Twenty male elite soccer players (SP, age 14.5 ± 0.4 years) and 20 male control subjects (CS, age 14.3 ± 0.3 years) participated in the study. Anthropometric measurements, aerobic (Yo-Yo Intermittent Recovery Test Level 1 [YYIRT1]) and anaerobic soccer relevant performances (jump and sprint tests), blood testosterone (T), cortisol (C), sex hormone binding globulin (SHBG), and T/C ratio were assessed 5 times (from T0 to T4) during 2 competitive seasons. Significant differences from basal values (Δ) of T, SHBG, and C between SP and CS were observed (p < 0.01). Additionally, T and T/C ratio changes were positively correlated with physical performance (p ≤ 0.05). In conclusion, as expected, higher T concentration and greater power performance were observed in the soccer players group compared with controls. Our findings also show that the T concentrations and power performance outcomes co-vary positively over the 2 soccer seasons in soccer players.

Evaluating injury risk in first and second league professional Portuguese soccer: muscular strength and asymmetry.

PubMed

Carvalho, Alberto; Brown, Scott; Abade, Eduardo

2016-06-01

Strength imbalances between the hamstrings and quadriceps are an essential predictor for hamstring strain in soccer. The study aimed to investigate and compare the muscle strength imbalances of professional soccer players of different performance levels. One hundred and fifty nine senior male professional soccer players from first (n = 75) and second league (n = 84) Portuguese clubs participated in this study. Muscle strength was evaluated with a REV9000 isokinetic dynamometer. Maximal peak torque data were used to calculate quadriceps and hamstrings strength during concentric and eccentric actions, bilateral asymmetry, conventional strength ratios and dynamic control ratios. Second league athletes produced slightly lower conventional strength ratios in the right and left legs (ES = 0.22, p = 0.17 and ES = 0.36, p = 0.023, respectively) compared to the first league athletes. No significant differences were found in dynamic control ratios or in bilateral asymmetry among first and second league athletes. These findings do not show a clear link between the competitive level and injury risk in soccer players. However, some of the differences found, particularly in conventional strength ratios, highlight the importance of performing off-season and pre-season strength assessments to prescribe and adjust individual strength training programs among professional soccer players.

Evaluating injury risk in first and second league professional Portuguese soccer: muscular strength and asymmetry

PubMed Central

Carvalho, Alberto; Brown, Scott

2016-01-01

Abstract Strength imbalances between the hamstrings and quadriceps are an essential predictor for hamstring strain in soccer. The study aimed to investigate and compare the muscle strength imbalances of professional soccer players of different performance levels. One hundred and fifty nine senior male professional soccer players from first (n = 75) and second league (n = 84) Portuguese clubs participated in this study. Muscle strength was evaluated with a REV9000 isokinetic dynamometer. Maximal peak torque data were used to calculate quadriceps and hamstrings strength during concentric and eccentric actions, bilateral asymmetry, conventional strength ratios and dynamic control ratios. Second league athletes produced slightly lower conventional strength ratios in the right and left legs (ES = 0.22, p = 0.17 and ES = 0.36, p = 0.023, respectively) compared to the first league athletes. No significant differences were found in dynamic control ratios or in bilateral asymmetry among first and second league athletes. These findings do not show a clear link between the competitive level and injury risk in soccer players. However, some of the differences found, particularly in conventional strength ratios, highlight the importance of performing off-season and pre-season strength assessments to prescribe and adjust individual strength training programs among professional soccer players. PMID:28149364

The effect of a 4-week training regimen on body fat and aerobic capacity of professional soccer players during the transition period.

PubMed

Sotiropoulos, Aristomenis; Travlos, Antonios K; Gissis, Ioannis; Souglis, Atnanasios G; Grezios, Apostolos

2009-09-01

The purpose of this study was to evaluate the changes in body fat percentage and aerobic capacity in professional soccer players, after the implementation of a specific 4-week training regimen during the transition period. Fifty-eight professional soccer players of the Greek Premier National Division were separated in experimental (n = 38) and control groups (n = 20). Body composition and maximum oxygen intake were evaluated before and after a 4-week training regimen followed during the transition period. The experimental design used for analyzing weight (kg), percent body fat (%) and VO2 max values (ml x kg(-1) x min(-1)) was a 2 x 2 (Groups x Measures), with Groups as a between-subjects factor and Measures as a within-subjects factor. The level of significance was set at p < or = 0.05 for all analyses. Analyses of variances showed that the experimental and the control groups achieved statistically significant (a) increases from pretest to posttest measures in body weight (0.595 kg and 1.425 kg, respectively) and percent body fat (0.25 and 0.82, respectively), and (b) decreases in VO2 max values from pretest to posttest measures (0.81 and 3.56, respectively). The findings of the study revealed that the players who followed the training regimen compared with the players that did not follow any specific training program gained less weight and body fat and exhibited lower reduction in their VO2 max values.

Variety Wins: Soccer-Playing Robots and Infant Walking.

PubMed

Ossmy, Ori; Hoch, Justine E; MacAlpine, Patrick; Hasan, Shohan; Stone, Peter; Adolph, Karen E

2018-01-01

Although both infancy and artificial intelligence (AI) researchers are interested in developing systems that produce adaptive, functional behavior, the two disciplines rarely capitalize on their complementary expertise. Here, we used soccer-playing robots to test a central question about the development of infant walking. During natural activity, infants' locomotor paths are immensely varied. They walk along curved, multi-directional paths with frequent starts and stops. Is the variability observed in spontaneous infant walking a "feature" or a "bug?" In other words, is variability beneficial for functional walking performance? To address this question, we trained soccer-playing robots on walking paths generated by infants during free play and tested them in simulated games of "RoboCup." In Tournament 1, we compared the functional performance of a simulated robot soccer team trained on infants' natural paths with teams trained on less varied, geometric paths-straight lines, circles, and squares. Across 1,000 head-to-head simulated soccer matches, the infant-trained team consistently beat all teams trained with less varied walking paths. In Tournament 2, we compared teams trained on different clusters of infant walking paths. The team trained with the most varied combination of path shape, step direction, number of steps, and number of starts and stops outperformed teams trained with less varied paths. This evidence indicates that variety is a crucial feature supporting functional walking performance. More generally, we propose that robotics provides a fruitful avenue for testing hypotheses about infant development; reciprocally, observations of infant behavior may inform research on artificial intelligence.

Influence of oxygen uptake kinetics on physical performance in youth soccer.

PubMed

Doncaster, Greg; Marwood, Simon; Iga, John; Unnithan, Viswanath

2016-09-01

To examine the relationship between oxygen uptake kinetics (VO2 kinetics) and physical measures associated with soccer match play, within a group of highly trained youth soccer players. Seventeen highly trained youth soccer players (age: 13.3 ± 0.4 year, self-assessed Tanner stage: 3 ± 1) volunteered for the study. Players initially completed an incremental treadmill protocol to exhaustion, to establish gaseous exchange threshold (GET) and VO2max (59.1 ± 5.4 mL kg(-1) min(-1)). On subsequent visits, players completed a step transition protocol from rest-moderate-intensity exercise, followed by an immediate transition, and from moderate- to severe-intensity exercise (moderate: 95 % GET, severe: 60 %∆), during which VO2 kinetics were determined. Physical soccer-based performance was assessed using a maximal Yo-Yo intermittent recovery test level 1 (Yo-Yo IR1) and via GPS-derived measures of physical soccer performance during soccer match play, three 2 × 20 min, 11 v 11 matches, to gain measures of physical performance during soccer match play. Partial correlations revealed significant inverse relationships between the unloaded-to-moderate transition time constant (tau) and: Yo-Yo IR1 performance (r = -0.58, P = 0.02) and GPS variables [total distance (TD): r = -0.64, P = 0.007, high-speed running (HSR): r = -0.64, P = 0.008 and high-speed running efforts (HSReff): r = -0.66, P = 0.005]. Measures of VO2 kinetics are related to physical measures associated with soccer match play and could potentially be used to distinguish between those of superior physical performance, within a group of highly trained youth soccer players.

Youth Sport Development through Soccer: An Evaluation of an After-School Program Using the TPSR Model

ERIC Educational Resources Information Center

Cryan, Mark; Martinek, Thomas

2017-01-01

The Soccer Coaching Club program used the Teaching Personal and Social Responsibility (TPSR) model in an after-school soccer program for sixth grade boys between 11 and 12 years old in a local middle school. Soccer, as the featured physical activity, provided the "hook" for regular attendance. Desired outcomes included improved…

Exercise physiology and nutritional perspectives of elite soccer refereeing.

PubMed

Schenk, K; Bizzini, M; Gatterer, H

2018-03-01

Referees are an integral part of soccer, and their performance is fundamental for regular match flow, irrespective of the competition level or age classes. So far, scientific interest was mainly limited to aspects of exercise physiology and match performance of soccer referees, whereas recommendations for nutrition were adopted from active professional soccer. In contrast to elite soccer players, most referees are non-professional and engaged in different occupations. Furthermore, elite referees and soccer players differ in regard to age, body composition, aerobic capacity, and training load. Thus, referees' caloric needs and recommended daily carbohydrate intake may generally be lower compared to active soccer players, with higher intakes limited to periods of increased training load and match days or for referees engaged in physical demanding occupations. With respect to fluid intake, pre-match and in-match hydration strategies generally valid in sports are recommended also for referees to avoid cognitive and physical performance loss, especially when officiating in extreme climates and altitude. In contrast to elite soccer, professional assistance concerning nutrition and training is rarely available for national elite referees of most countries. Therefore, special attention on education about adequate nutrition and fluid intake, about the dietary prevention of deficiencies (iron in female referees, vitamin D irrespective of sex and age), and basic precautions for travels abroad is warranted. In conclusion, the simple adoption of nutritional considerations from active soccer for referees may not be appropriate. Recommendations should respect gender differences, population-specific physical characteristics, and demands just as well as individual characteristics and special needs. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Effects of Exercise Training under Hyperbaric Oxygen on Oxidative Stress Markers and Endurance Performance in Young Soccer Players: A Pilot Study.

PubMed

Burgos, Carlos; Henríquez-Olguín, Carlos; Andrade, David Cristóbal; Ramírez-Campillo, Rodrigo; Araneda, Oscar F; White, Allan; Cerda-Kohler, Hugo

2016-01-01

The aim of the present study was to determine the effects of three weeks of hyperbaric oxygen (HBO 2 ) training on oxidative stress markers and endurance performance in young soccer players. Participants (18.6 ± 1.6 years) were randomized into hyperbaric-hyperoxic (HH) training ( n = 6) and normobaric normoxic (NN) training ( n = 6) groups. Immediately before and after the 5th, 10th, and 15th training sessions, plasma oxidative stress markers (lipid hydroperoxides and uric acid), plasma antioxidant capacity (6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid [TROLOX]), arterial blood gases, acid-base balance, bases excess (BE), and blood lactate analyses were performed. Before and after intervention, maximal oxygen uptake (VO 2 max) and peak power output (PPO) were determined. Neither HH nor NN experienced significant changes on oxidative stress markers or antioxidant capacity during intervention. VO 2 max and PPO were improved (moderate effect size) after HH training. The results suggest that HBO 2 endurance training does not increase oxidative stress markers and improves endurance performance in young soccer players. Our findings warrant future investigation to corroborate that HBO 2 endurance training could be a potential training approach for highly competitive young soccer players.

Effects of Exercise Training under Hyperbaric Oxygen on Oxidative Stress Markers and Endurance Performance in Young Soccer Players: A Pilot Study

PubMed Central

Henríquez-Olguín, Carlos; Andrade, David Cristóbal; Ramírez-Campillo, Rodrigo; White, Allan; Cerda-Kohler, Hugo

2016-01-01

The aim of the present study was to determine the effects of three weeks of hyperbaric oxygen (HBO2) training on oxidative stress markers and endurance performance in young soccer players. Participants (18.6 ± 1.6 years) were randomized into hyperbaric-hyperoxic (HH) training (n = 6) and normobaric normoxic (NN) training (n = 6) groups. Immediately before and after the 5th, 10th, and 15th training sessions, plasma oxidative stress markers (lipid hydroperoxides and uric acid), plasma antioxidant capacity (6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid [TROLOX]), arterial blood gases, acid-base balance, bases excess (BE), and blood lactate analyses were performed. Before and after intervention, maximal oxygen uptake (VO2max) and peak power output (PPO) were determined. Neither HH nor NN experienced significant changes on oxidative stress markers or antioxidant capacity during intervention. VO2max and PPO were improved (moderate effect size) after HH training. The results suggest that HBO2 endurance training does not increase oxidative stress markers and improves endurance performance in young soccer players. Our findings warrant future investigation to corroborate that HBO2 endurance training could be a potential training approach for highly competitive young soccer players. PMID:28083148

Effects of plyometric training and creatine supplementation on maximal-intensity exercise and endurance in female soccer players.

PubMed

Ramírez-Campillo, Rodrigo; González-Jurado, José Antonio; Martínez, Cristian; Nakamura, Fábio Yuzo; Peñailillo, Luis; Meylan, Cesar M P; Caniuqueo, Alexis; Cañas-Jamet, Rodrigo; Moran, Jason; Alonso-Martínez, Alicia M; Izquierdo, Mikel

2016-08-01

To investigate the effects of a six-week plyometric training and creatine supplementation intervention on maximal-intensity and endurance performance in female soccer players during in-season training. Randomized, double-blind, placebo-controlled trial. Young (age 22.9±2.5y) female players with similar training load and competitive background were assigned to a plyometric training group receiving placebo (PLACEBO, n=10), a plyometric training group receiving creatine supplementation (CREATINE, n=10) or a control group receiving placebo without following a plyometric program (CONTROL, n=10). Athletes were evaluated for jumping, maximal and repeated sprinting, endurance and change-of-direction speed performance before and after six weeks of training. After intervention the CONTROL group did not change, whereas both plyometric training groups improved jumps (ES=0.25-0.49), sprint (ES=0.35-0.41), repeated sprinting (ES=0.48-0.55), endurance (ES=0.32-0.34) and change-of-direction speed performance (ES=0.46-0.55). However, the CREATINE group improved more in the jumps and repeated sprinting performance tests than the CONTROL and the PLACEBO groups. Adaptations to plyometric training may be enhanced with creatine supplementation. Copyright © 2015 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

The Transition Period in Soccer: A Window of Opportunity.

PubMed

Silva, Joao Renato; Brito, Joao; Akenhead, Richard; Nassis, George P

2016-03-01

The aim of this paper is to describe the physiological changes that occur during the transition period in soccer players. A secondary aim is to address the issue of utilizing the transition period to lay the foundation for the succeeding season. We reviewed published peer-reviewed studies if they met the following three selection criteria: (1) the studied population comprised adult soccer players (aged >18 years), (2) time points of physiological and performance assessments were provided, and (3) appropriate statistics for the calculation of effect sizes were reported. Following two selection phases, 12 scientific publications were considered, involving a total sample of 252 players. The transition period elicits small to moderate negative changes in body composition, a moderate decline in sprint performance with and without changes of direction, and small to moderate decrements in muscle power. Detraining effects are also evident for endurance-related physiological and performance outcomes: large decrements in maximal oxygen consumption V̇O2max) and time to exhaustion, and moderate to very large impairments have been observed in intermittent-running performance. Off-season programs should be characterized by clear training objectives, a low frequency of training sessions, and simple training tools in order to facilitate compliance. The program suggested here may constitute the 'minimum effective dose' to maintain or at least attenuate the decay of endurance- and neuromuscular-related performance parameters, as well as restore an adequate strength profile (reduce muscle strength imbalances). This periodization strategy may improve the ability of players to cope with the elevated training demands of pre-season training and therefore reduce the risk of injury. Moreover, this strategy will favor a more efficient development of other relevant facets of performance during the pre-competition phase (e.g., tactical organization). We contend that the transition period needs to be perceived as a 'window of opportunity' for players to both recover and 'rebuild' for the following season.

Effect of Sequencing Strength and Endurance Training in Young Male Soccer Players.

PubMed

Makhlouf, Issam; Castagna, Carlo; Manzi, Vincenzo; Laurencelle, Louis; Behm, David G; Chaouachi, Anis

2016-03-01

This study examined the effects of strength and endurance training sequence (strength before or after endurance) on relevant fitness variables in youth soccer players. Fifty-seven young elite-level male field soccer players (13.7 ± 0.5 years; 164 ± 8.3 cm; 53.5 ± 8.6 kg; body fat; 15.6 ± 3.9%) were randomly assigned to a control (n = 14, CG) and 3 experimental training groups (twice a week for 12 weeks) strength before (SE, n = 15), after (ES, n = 14) or on alternate days (ASE, n = 14) with endurance training. A significant (p = 0.001) intervention main effect was detected. There were only trivial training sequence differences (ES vs. SE) for all variables (p > 0.05). The CG showed large squat 1 repetition maximum (1RM) and medium sprint, change of direction ability, and jump improvements. ASE demonstrated a trivial difference in endurance performance with ES and SE (p > 0.05). Large to medium greater improvements for SE and ES were reported compared with ASE for sprinting over 10 and 30 m (p < 0.02). The SE squat 1RM was higher than in ASE (moderate, p < 0.02). Postintervention differences between ES and SE with CG fitness variables were small to medium (p ≤ 0.05) except for a large SE advantage with the Yo-Yo intermittent recovery test (p < 0.001, large). This study showed no effect of intrasession training sequence on soccer fitness-relevant variables. However, combining strength and endurance within a single training session provided superior results vs. training on alternate days. Concurrent training may be considered as an effective and safe training method for the development of the prospective soccer player.

Variety Wins: Soccer-Playing Robots and Infant Walking

PubMed Central

Ossmy, Ori; Hoch, Justine E.; MacAlpine, Patrick; Hasan, Shohan; Stone, Peter; Adolph, Karen E.

2018-01-01

Although both infancy and artificial intelligence (AI) researchers are interested in developing systems that produce adaptive, functional behavior, the two disciplines rarely capitalize on their complementary expertise. Here, we used soccer-playing robots to test a central question about the development of infant walking. During natural activity, infants' locomotor paths are immensely varied. They walk along curved, multi-directional paths with frequent starts and stops. Is the variability observed in spontaneous infant walking a “feature” or a “bug?” In other words, is variability beneficial for functional walking performance? To address this question, we trained soccer-playing robots on walking paths generated by infants during free play and tested them in simulated games of “RoboCup.” In Tournament 1, we compared the functional performance of a simulated robot soccer team trained on infants' natural paths with teams trained on less varied, geometric paths—straight lines, circles, and squares. Across 1,000 head-to-head simulated soccer matches, the infant-trained team consistently beat all teams trained with less varied walking paths. In Tournament 2, we compared teams trained on different clusters of infant walking paths. The team trained with the most varied combination of path shape, step direction, number of steps, and number of starts and stops outperformed teams trained with less varied paths. This evidence indicates that variety is a crucial feature supporting functional walking performance. More generally, we propose that robotics provides a fruitful avenue for testing hypotheses about infant development; reciprocally, observations of infant behavior may inform research on artificial intelligence. PMID:29867427

Sport activities differentiating match-play improvement in elite youth footballers - a 2-year longitudinal study.

PubMed

Güllich, Arne; Kovar, Peter; Zart, Sebastian; Reimann, Ansgar

2017-02-01

This study examined contributions of different types of sport activities to the development of elite youth soccer performance. Match-play performance of 44 German male players was assessed by expert coaches twice, 24 months apart (age 11.1-13.1 years), based on videotaped 5v5 matches. Player pairs were matched by identical age and initial performance at t 1 . Each player was assigned to a group of either "Strong" or "Weak Responders" based on a higher or lower subsequent performance improvement at t 2 within each pair (mean Δperformance 29% vs. 7%). A questionnaire recorded current and earlier amounts of organised practice/training and non-organised sporting play, in soccer and other sports, respectively. Group comparison revealed that "Strong Responders" accumulated more non-organised soccer play and organised practice/training in other sports, but not more organised soccer practice/training. Subsequent multivariate analyses (multiple linear regression analyses (MLR)) highlighted that higher resultant match-play performance at t 2 was accounted for R 2 adj  = 0.65 by performance at t 1 , together with more non-organised soccer play and organised engagement in other sports, respectively, and greater current, but less earlier volume of organised soccer. The findings suggest that variable early sporting experience facilitates subsequent soccer performance development in German elite youth footballers.

Association Between MCT1 A1470T Polymorphism and Fat-Free Mass in Well-Trained Young Soccer Players.

PubMed

Massidda, Myosotis; Eynon, Nir; Bachis, Valeria; Corrias, Laura; Culigioni, Claudia; Cugia, Paolo; Scorcu, Marco; Calò, Carla M

2016-04-01

The aim of this study was to investigate the association between the MCT1 A1470T polymorphism and fat-free mass in young Italian elite soccer players. Participants were 128 Italian male soccer players. Fat-free mass was estimated for each of the soccer player using age- and gender-specific formulas with plicometry. Genotyping for the MCT1 A1470T polymorphism was performed using polymerase chain reaction. The MCT1 A1470T genotypes were in agreement with the Hardy-Weinberg equilibrium distribution. The percentage of fat-free mass was significantly higher in soccer players with the TT genotype and in the T-allele-dominant model group (TT + AT) compared with the soccer players with the AA genotype. The MCT1 T allele is associated with the percentage of fat-free mass in young elite male soccer players. Elucidating the genetic basis of body composition in athletes could potentially be used as an additional tool for strength and conditioning professionals in planning and adjusting training. However, these results are preliminary and need to be replicated in more cohorts.

Sport-specific trunk muscle profiles in soccer players of different skill levels.

PubMed

Krutsch, Werner; Weishaupt, Philipp; Zeman, Florian; Loibl, Markus; Neumann, Carsten; Nerlich, Michael; Angele, Peter

2015-05-01

Physical fitness and trunk stability are essential factors for successful soccer competition. We investigated the impact of soccer exposure on the trunk muscle profile of players of different skill levels. Professional and amateur soccer players were examined for trunk flexibility and maximum isometric muscle strength in the midseason period 2011. 24 professional soccer players who had not participated in any specific trunk muscle training programmes had significantly higher isometric trunk muscle strength in the sagittal plane (Ext: p = 0.003, Flex: p = 0.014), the frontal plane (Lat. right: p = 0.001, left: p = 0.003) and the transverse plane (Rotation right and left: p < 0.001) than 83 amateur soccer players. Professional players also had higher trunk flexibility in the sagittal plane (Flex: p = 0.001) and the transverse plane (Rotation right: p = 0.02, left: p = 0.002) than amateur players. The side of the dominant kicking leg had no influence on muscle strength and flexibility of the trunk. Trunk flexibility and stability as necessary factors for avoiding physical overstress and injuries are differently trained in player of different soccer skill levels.

Analysis of Injury Incidences in Male Professional Adult and Elite Youth Soccer Players: A Systematic Review.

PubMed

Pfirrmann, Daniel; Herbst, Mark; Ingelfinger, Patrick; Simon, Perikles; Tug, Suzan

2016-05-01

The incidence of injury for elite youth and professional adult soccer players is an important concern, but the risk factors for these groups are different. To summarize and compare the injury incidences and injury characteristics of male professional adult and elite youth soccer players. We searched MEDLINE and Web of Science using the search terms elite, international, European, soccer, football, injury, injuries, epidemiology, incidence, prevalence, not female, not American football, and not rugby. We also used the search terms professional for studies on professional adult soccer players and high-level, soccer academy, youth, adolescent, and young for studies on elite youth soccer players. Eligible studies were published in English, had a prospective cohort design, and had a minimum study period of 6 months. To ensure that injury data were assessed in relationship to the athlete's individual exposure, we included only studies that reported on injuries and documented exposure volume. Two independent reviewers applied the selection criteria and assessed the quality of the studies. A total of 676 studies were retrieved from the literature search. Eighteen articles met the inclusion criteria: 6 for elite youth and 12 for professional adult soccer players. Injury rates were higher for matches than for training for both youth and adult players. Youth players had a higher incidence of training injuries than professionals. Efforts must be made to reduce the overall injury rate in matches. Therefore, preventive interventions, such as adequately enforcing rules and focusing on fair play, must be analyzed and developed to reduce match-related injury incidences. Reducing training injuries should be a particular focus for youth soccer players.

Analysis of Injury Incidences in Male Professional Adult and Elite Youth Soccer Players: A Systematic Review

PubMed Central

Pfirrmann, Daniel; Herbst, Mark; Ingelfinger, Patrick; Simon, Perikles; Tug, Suzan

2016-01-01

Context:  The incidence of injury for elite youth and professional adult soccer players is an important concern, but the risk factors for these groups are different. Objective:  To summarize and compare the injury incidences and injury characteristics of male professional adult and elite youth soccer players. Data Sources:  We searched MEDLINE and Web of Science using the search terms elite, international, European, soccer, football, injury, injuries, epidemiology, incidence, prevalence, not female, not American football, and not rugby. We also used the search terms professional for studies on professional adult soccer players and high-level, soccer academy, youth, adolescent, and young for studies on elite youth soccer players. Study Selection:  Eligible studies were published in English, had a prospective cohort design, and had a minimum study period of 6 months. To ensure that injury data were assessed in relationship to the athlete's individual exposure, we included only studies that reported on injuries and documented exposure volume. Data Extraction:  Two independent reviewers applied the selection criteria and assessed the quality of the studies. Data Synthesis:  A total of 676 studies were retrieved from the literature search. Eighteen articles met the inclusion criteria: 6 for elite youth and 12 for professional adult soccer players. Conclusions:  Injury rates were higher for matches than for training for both youth and adult players. Youth players had a higher incidence of training injuries than professionals. Efforts must be made to reduce the overall injury rate in matches. Therefore, preventive interventions, such as adequately enforcing rules and focusing on fair play, must be analyzed and developed to reduce match-related injury incidences. Reducing training injuries should be a particular focus for youth soccer players. PMID:27244125

Hamstring injury prevention in soccer: Before or after training?

PubMed

Lovell, R; Knox, M; Weston, M; Siegler, J C; Brennan, S; Marshall, P W M

2018-02-01

We examined the effects of a 12-week program of Nordic hamstring exercises (NHE), administered before or after football training, upon eccentric hamstring strength, muscle activity, and architectural adaptations. Amateur soccer players were randomized into three groups. The control group (CON; n=11) undertook core stability exercises, whereas a periodized NHE program was delivered either before (NHE BEF ; n=10) or after (NHE AFT ; n=14) biweekly training sessions. Outcome measures included peak torque and concomitant normalized peak surface electromyography signals (sEMG) of the biceps femoris (BF) and medial hamstring (MH) muscles during knee flexor maximal eccentric contractions, performed at 30°·s -1 . Ultrasonography was used to determine BF muscle thickness, muscle fiber pennation angle, and fascicle length. Performing the NHE derived likely moderate peak torque increases in both NHE BEF (+11.9%; 90% confidence interval: 3.6%-20.9%) and NHE AFT (+11.6%; 2.6%-21.5%) vs CON. Maximum sEMG increases were moderately greater in the BF of both NHE training groups vs CON. There were likely moderate increases in BF muscle thickness (+0.17 cm; 0.05-0.29 cm) and likely small pennation angle increases (+1.03°; -0.08° to 2.14°) in NHE AFT vs CON and NHE BEF . BF fascicle length increases were likely greater in NHE BEF (+1.58 cm; 0.48-2.68 cm; small effect) vs CON and NHE AFT . A 12-week eccentric hamstring strengthening program increased strength and sEMG to a similar magnitude irrespective of its scheduling relative to the football training session. However, architectural adaptations to support the strength gains differed according to the timing of the injury prevention program. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Explosive strength and endurance adaptations in young elite soccer players during two soccer seasons.

PubMed

Di Giminiani, Riccardo; Visca, Christiano

2017-01-01

The purpose of the present study was to investigate the explosive strength and endurance adaptations in young elite soccer players who underwent a supervised training program for a period of two years. Nineteen players, with seven years of training experience (age: 13.3 ± 0.1 years; body weight: 57.9 ± 4.9 kg; height: 168.9 ± 4.7 cm; BMI: 20.1 ± 1.1 kg/m2), voluntarily participated in the present study. The testing sessions were performed at the beginning of the preparation period in the first (T1), second (T2), and third year (T3). The following performance variables were measured: explosive strength [squat-jump (SJ) and counter-movement-jump (CMJ)], pre-stretch augmentation (CMJ-SJ), leg stiffness [hopping test (HT)], short sprint performance [15 m (SSP15) and 30 m (SSP30)], aerobic endurance [test of Leger (VO2max)], maximal heart rate [at the last step of Leger (HR)], and speed-strength endurance [continuous counter-movement-jumps (CCMJ)]. A significant main effect on the VO2Max (+5.72%; F(2.49) = 3.822; p = 0.029; ES = 1.00), HR (-1.70%; F(2.54) = 3.472; p = 0.038; ES = 0.97), CCMJ (+7.64%; F(2.54) = 5.438; p = 0.007; ES = 1.15), SJ (+10.26%; F(2.54) = 15.254; p = 0.0001; ES = 1.53), CMJ (+7.36; F(2.54) = 8.270; p = 0.001; ES = 1.33), HT (+8.34%; F(2.48) = 3.297; p = 0.046; ES = 1.01), SSP15 (-3.50%; F(2.44) = 12.760; p = 0.0001; ES = 1.53), and SSP30 (-4.44%; F(2.44) = 5.797; p = 0.006; ES = 1.16) was observed in the two soccer seasons. These results highlight that, in long-term training, the monitoring of the adaptive responses in relation to the training load may provide a guideline to optimize the trainability of some performance variables in young elite soccer players (13-15 years). In the present study, we cannot exclude the influence of growth and maturation on some performance variables; therefore, the monitored adaptive responses should be considered as the possible results of an interaction between the applied training load and maturation.

Explosive strength and endurance adaptations in young elite soccer players during two soccer seasons

PubMed Central

Visca, Christiano

2017-01-01

The purpose of the present study was to investigate the explosive strength and endurance adaptations in young elite soccer players who underwent a supervised training program for a period of two years. Nineteen players, with seven years of training experience (age: 13.3 ± 0.1 years; body weight: 57.9 ± 4.9 kg; height: 168.9 ± 4.7 cm; BMI: 20.1 ± 1.1 kg/m2), voluntarily participated in the present study. The testing sessions were performed at the beginning of the preparation period in the first (T1), second (T2), and third year (T3). The following performance variables were measured: explosive strength [squat-jump (SJ) and counter-movement-jump (CMJ)], pre-stretch augmentation (CMJ-SJ), leg stiffness [hopping test (HT)], short sprint performance [15 m (SSP15) and 30 m (SSP30)], aerobic endurance [test of Leger (VO2max)], maximal heart rate [at the last step of Leger (HR)], and speed-strength endurance [continuous counter-movement-jumps (CCMJ)]. A significant main effect on the VO2Max (+5.72%; F(2.49) = 3.822; p = 0.029; ES = 1.00), HR (-1.70%; F(2.54) = 3.472; p = 0.038; ES = 0.97), CCMJ (+7.64%; F(2.54) = 5.438; p = 0.007; ES = 1.15), SJ (+10.26%; F(2.54) = 15.254; p = 0.0001; ES = 1.53), CMJ (+7.36; F(2.54) = 8.270; p = 0.001; ES = 1.33), HT (+8.34%; F(2.48) = 3.297; p = 0.046; ES = 1.01), SSP15 (-3.50%; F(2.44) = 12.760; p = 0.0001; ES = 1.53), and SSP30 (-4.44%; F(2.44) = 5.797; p = 0.006; ES = 1.16) was observed in the two soccer seasons. These results highlight that, in long-term training, the monitoring of the adaptive responses in relation to the training load may provide a guideline to optimize the trainability of some performance variables in young elite soccer players (13–15 years). In the present study, we cannot exclude the influence of growth and maturation on some performance variables; therefore, the monitored adaptive responses should be considered as the possible results of an interaction between the applied training load and maturation. PMID:28192512

The preventive effect of a soccer-specific ankle brace on acute lateral ankle sprains in girls amateur soccer players: study protocol of a cluster-randomised controlled trial.

PubMed

Thijs, Karin; Huisstede, Bionka; Goedhart, Edwin; Backx, Frank

2017-07-27

Acute lateral ankle sprains are the single most often diagnosed injury in female soccer players and often result in an inability to play. This highlights the need for effective prevention strategies. Proprioceptive training and/or the use of an external support to decrease inversion of the ankle joint can prevent or reduce the number of acute lateral ankle sprains. The effectiveness of a soccer-specific ankle brace in reducing first-time and recurrent acute lateral ankle sprains has never been investigated in girl soccer players. If effective, ankle braces could be introduced into soccer. Cluster-randomised controlled trial. Girl amateur soccer players (aged 14-18 years) will be allocated to an intervention or control group. The intervention group will be instructed to wear soccer-specific ankle braces on both ankles during soccer training and matches; the control group will continue playing soccer as usual. Primary outcomes are the incidence and severity of acute lateral ankle sprains. Secondary outcomes are the prognostic value of generalised joint hypermobility and functional stability on the risk of acute lateral ankle sprains and compliance with the intervention. The findings from this study may provide evidence to support the use of a soccer-specific ankle brace to prevent lateral ankle sprains during soccer. We hypothesise that this brace will reduce the incidence of ankle sprains among young amateur girl soccer players by 50%. The prevention of such injuries will be beneficial to players, clubs and society. The Netherlands Trial Register (NTR): NTR6045; Pre-results. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

P-Soccer: Soccer Games Application using Kinect

NASA Astrophysics Data System (ADS)

Nasir, Mohamad Fahim Mohamed; Suparjoh, Suriawati; Razali, Nazim; Mustapha, Aida

2018-05-01

This paper presents a soccer game application called P-Soccer that uses Kinect as the interaction medium between users and the game characters. P-Soccer focuses on training penalty kicks with one character who is taking the kick. This game is developed based on the Game Development Life Cycle (GDLC) methodology. Results for alpha and beta testing showed that the target users are satisfied with overall game design and theme as well as the interactivity with the main character in the game.

Laterality-Specific Training Improves Mental Rotation Performance in Young Soccer Players.

PubMed

Pietsch, Stefanie; Jansen, Petra

2018-01-01

This study investigates the influence of specific soccer training with the non-dominant leg on mental rotation performance of 20 adolescent soccer players between 10 and 11 years of age. While the experimental group performed soccer specific tasks only with the non-dominant foot once a week for 10 weeks, the control group absolved the same exercises with the dominant foot for the same period of time. Both groups performed a mental rotation task and shot, dribbling and ball control tests before and after the 10 week intervention. The most relevant result was that the experimental group showed a significantly larger increase in mental rotation ability than the control group.

Laterality-Specific Training Improves Mental Rotation Performance in Young Soccer Players

PubMed Central

Pietsch, Stefanie; Jansen, Petra

2018-01-01

This study investigates the influence of specific soccer training with the non-dominant leg on mental rotation performance of 20 adolescent soccer players between 10 and 11 years of age. While the experimental group performed soccer specific tasks only with the non-dominant foot once a week for 10 weeks, the control group absolved the same exercises with the dominant foot for the same period of time. Both groups performed a mental rotation task and shot, dribbling and ball control tests before and after the 10 week intervention. The most relevant result was that the experimental group showed a significantly larger increase in mental rotation ability than the control group. PMID:29535665

Comparison of inflammatory responses to a soccer match between elite male and female players.

PubMed

Souglis, Athanasios G; Papapanagiotou, Angeliki; Bogdanis, Gregory C; Travlos, Antonis K; Apostolidis, Nikolaos G; Geladas, Nikolaos D

2015-05-01

The aim of this study was to compare the inflammatory responses between male and female soccer players for a period of 48 hours after an official match. Blood samples were taken from 83 subjects (22 elite male and 21 elite female soccer players and 20 male and 20 female inactive individuals) in the morning of the game day, immediately after the soccer game and 24 and 48 hours after the match. Average relative exercise intensity during the match was similar in male and female players, as indicated by mean heart rate that was 86.9 ± 4.3 and 85.6 ± 2.3% of maximal heart rate (p = 0.23), respectively. Interleukin 6 (IL-6) and tumor necrosis factor alpha (TNF-α) increased 2- to 4-fold above resting values, peaking immediately after the match. C-reactive protein (CRP) and creatine kinase peaked 24 hours after the match. Interleukin 6, CRP, and creatine kinase responses were similar in male and female players, but the peak in TNF-α was 18% higher in male players. Interleukin 6, TNF-α, and CRP at rest were lower in male and female players compared with the control subjects, suggesting a protective effect of regular exercise training regarding the inflammatory profile. The results of this study show that a soccer match induces significant inflammatory responses in both male and female players, with only TNF-α peak values being lower in females. Because of the effects of inflammatory responses on performance and health of the players, it is suggested that coaches and trainers should adjust exercise training programs after a match to promote recovery and protect the athletes' health.

Nutritional guidance to soccer players for training and competition.

PubMed

Clark, K

1994-01-01

Strategies for a nutrition education as applied to individual soccer players provide a key to guiding them towards appropriate food selection. Scientific investigations have associated energy requirements, composition of the diet and carbohydrate intake with muscle glycogen storage, and adequacy of fluids with optimal athletic performance. In general, soccer players appear to consume adequate energy but low carbohydrate diets. The training diet should be comprised of 55-65% carbohydrate, 12-15% protein and less than 30% fat. The goal of the training diet is to provide adequate energy for weight maintenance, and 7-10 g of carbohydrate per kg body weight for maximizing glycogen storage. Nutritional needs for competition include eating prior to and after matches. Consumption of carbohydrate-rich foods for energy needs and glycogen resynthesis are key behaviours soccer players need to focus on daily. Qualified dietitians should be on hand to provide personal nutrition counselling, carbohydrate resource lists and education on food labels as simple and quick nutrition education strategies to guide soccer players, their parents, coaches and trainers towards improved food selections.

Nutrition and Supplementation in Soccer.

PubMed

Oliveira, César Chaves; Ferreira, Diogo; Caetano, Carlos; Granja, Diana; Pinto, Ricardo; Mendes, Bruno; Sousa, Mónica

2017-05-12

Contemporary elite soccer features increased physical demands during match-play, as well as a larger number of matches per season. Now more than ever, aspects related to performance optimization are highly regarded by both players and soccer coaches. Here, nutrition takes a special role as most elite teams try to provide an adequate diet to guarantee maximum performance while ensuring a faster recovery from matches and training exertions. It is currently known that manipulation and periodization of macronutrients, as well as sound hydration practices, have the potential to interfere with training adaptation and recovery. A careful monitoring of micronutrient status is also relevant to prevent undue fatigue and immune impairment secondary to a deficiency status. Furthermore, the sensible use of evidence-based dietary supplements may also play a role in soccer performance optimization. In this sense, several nutritional recommendations have been issued. This detailed and comprehensive review addresses the most relevant and up-to-date nutritional recommendations for elite soccer players, covering from macro and micronutrients to hydration and selected supplements in different contexts (daily requirements, pre, peri and post training/match and competition).

Nutrition and Supplementation in Soccer

PubMed Central

Oliveira, César Chaves; Ferreira, Diogo; Caetano, Carlos; Granja, Diana; Pinto, Ricardo; Mendes, Bruno; Sousa, Mónica

2017-01-01

Contemporary elite soccer features increased physical demands during match-play, as well as a larger number of matches per season. Now more than ever, aspects related to performance optimization are highly regarded by both players and soccer coaches. Here, nutrition takes a special role as most elite teams try to provide an adequate diet to guarantee maximum performance while ensuring a faster recovery from matches and training exertions. It is currently known that manipulation and periodization of macronutrients, as well as sound hydration practices, have the potential to interfere with training adaptation and recovery. A careful monitoring of micronutrient status is also relevant to prevent undue fatigue and immune impairment secondary to a deficiency status. Furthermore, the sensible use of evidence-based dietary supplements may also play a role in soccer performance optimization. In this sense, several nutritional recommendations have been issued. This detailed and comprehensive review addresses the most relevant and up-to-date nutritional recommendations for elite soccer players, covering from macro and micronutrients to hydration and selected supplements in different contexts (daily requirements, pre, peri and post training/match and competition). PMID:29910389

Leg Stiffness in Female Soccer Players: Intersession Reliability and the Fatiguing Effects of Soccer-Specific Exercise.

PubMed

De Ste Croix, Mark B A; Hughes, Jonathan D; Lloyd, Rhodri S; Oliver, Jon L; Read, Paul J

2017-11-01

De Ste Croix, MBA, Hughes, JD, Lloyd, RS, Oliver, JL, and Read, PJ. Leg stiffness in female soccer players: intersession reliability and the fatiguing effects of soccer-specific exercise. J Strength Cond Res 31(11): 3052-3058, 2016-Low levels of leg stiffness and reduced leg stiffness when fatigue is present compromise physical performance and increase injury risk. The purpose of this study was to (a) determine the reliability of leg stiffness measures obtained from contact mat data and (b) explore age-related differences in leg stiffness after exposure to a soccer-specific fatigue protocol in young female soccer players. Thirty-seven uninjured female youth soccer players divided into 3 subgroups based on chronological age (under 13 [U13], under 15 [U15], and under 17 [U17] year-olds) volunteered to participate in the study. After baseline data collection, during which relative leg stiffness, contact time, and flight time were collected, participants completed an age-appropriate soccer-specific fatigue protocol (SAFT). Upon completion of the fatigue protocol, subjects were immediately retested. Intersession reliability was acceptable and could be considered capable of detecting worthwhile changes in performance. Results showed that leg stiffness decreased in the U13 year-olds, was maintained in the U15 age group, and increased in the U17 players. Contact times and flight times did not change in the U13 and U15 year-olds, but significantly decreased and increased, respectively, in the U17 age group. The data suggest that age-related changes in the neuromuscular control of leg stiffness are present in youth female soccer players. Practitioners should be aware of these discrepancies in neuromuscular responses to soccer-specific fatigue, and should tailor training programs to meet the needs of individuals, which may subsequently enhance performance and reduce injury risk.

Eccentric Exercises Reduce Hamstring Strains in Elite Adult Male Soccer Players: A Critically Appraised Topic.

PubMed

Shadle, Ian B; Cacolice, Paul A

2017-11-01

Clinical Scenario: Hamstring strains are a common sport-related injury, which may limit athletic performance for an extended period of time. These injuries are common in the soccer setting. As such, it is important to determine an appropriate prevention program to minimize the risk of such an injury for these athletes. Eccentric hamstring training may be an effective and practical hamstring strain prevention strategy. What is the effect of eccentric exercises on hamstring strain prevention in adult male soccer players? Summary of Key Findings: Current literature was searched for studies of level 2 evidence or higher that investigated the effect of eccentric exercises in preventing hamstring strains in adult male soccer players. Three articles returned from the literature search met the inclusion criteria. A fourth article looked at differences in strength gains between eccentric and concentric hamstring strengthening exercises, but did not record hamstring strain incidence. A fifth article, a systematic review, met all the criteria except for the correct population. Of the 3 studies, 2 were randomized control trails and 1 was a cohort study. Clinical Bottom Line: There is robust supportive evidence that eccentric hamstring exercises can prevent a hamstring injury to an elite adult male soccer player. Therefore, it is recommended that athletic trainers and other sports medicine providers evaluate current practices relating to reducing hamstring strains and consider implementing eccentric exercise based prevention programs. Strength of Recommendation: All evidence was attained from articles with a level of evidence 2b or higher, based on the Center for Evidence-Based Medicine (CEBM) criteria, stating that eccentric exercises can decrease hamstring strains.

Alpha-amylase serum levels in professional soccer players are not related with physical fitness.

PubMed

Sanchis-Gomar, Fabian; Alis, Rafael; Rampinini, Ermanno; Bosio, Andrea; Romagnoli, Marco; Lombardi, Giovanni; Lippi, Giuseppe

2017-03-01

Recent evidence has showed that serum or salivary values of α-amylase predict endurance running performance. In this study we investigate whether serum α-amylase concentration may be associated with training status during a competitive season and after a detraining period in professional soccer players. The study population consisted in 15 male professional soccer players from an Italian major league team (age [mean±SD] 27±5 years, weight 76.9±4.1 kg, height 1.82±0.05 m). Serum α-amylase levels were measured 3 times during the last part of a competitive season (January, March and May) and just before preseason training (July). Metabolic and cardiovascular fitness of soccer players was improved during the last part of the season. The levels of α-amylase did not change significantly throughout the study period (χ2=7.331, P=0.062), nor they were found to be associated with variation of physical fitness and training status. The α-amylase fluctuations throughout a competitive season and after vacation time were meaningless in professional soccer players. No significant associations with physical fitness variations could be observed. These results suggest that α-amylase concentration may be a useful parameter for identifying individual inclination to endurance exercise, but not for predicting actual training status.

Effects of plyometric training on soccer players

PubMed Central

Wang, Ying-Chun; Zhang, Na

2016-01-01

Plyometric training (PT) is a technique used to increase strength and explosiveness. It consists of physical exercises in which muscles exert maximum force at short intervals to increase dynamic performances. In such a training, muscles undergo a rapid elongation followed by an immediate shortening (stretch-shortening contraction), utilizing the elastic energy stored during the stretching phase. There is consensus on the fact that when used, PT contributes to improvement in vertical jump performance, acceleration, leg strength, muscular power, increase of joint awareness and overall sport-specific skills. Consequently, PT which was primarily used by martial artists, sprinters and high jumpers to improve performances has gained in popularity and has been used by athletes in all types of sports. However, although PT has been shown to increase performance variables in many sports, little scientific information is currently available to determine whether PT actually enhances skill performance in soccer players, considering that soccer is an extremely demanding sport. Soccer players require dynamic muscular performance for fighting at all levels of training status, including rapid movements such as acceleration and deceleration of the body, change of direction, vertical and horizontal jumps, endurance, speed as well as power for kicking and tackling. In this review we discussed the effects of PT on soccer players by considering gender and age categories. PMID:27446242

Somatotype and stress hormone levels in young soccer players.

PubMed

Handziska, E; Handziski, Z; Gjorgoski, I; Dalip, M

2015-11-01

The relationship between somatotype and cortisol and adrenocorticotropic (ACTH) hormone concentrations at rest or after exercise in adolescent soccer players at different time points throughout a soccer season is not understood. Therefore, the aim of this study was to examine the relationship between somatotype and cortisol and ACTH concentrations at rest and after exercise in adolescent soccer players at different time points during a soccer season. During the first 4 months of the soccer season, 47 soccer players (between 15-17 years of age) were tested at three different time points including at baseline, after 6 weeks, and at the end of 4 months. Testing included anaerobic threshold (AnT, km/h) and maximal speed of running (Max, km/h) were measured with Conconi protocol on treadmill. Before and after a maximal exercise Test, plasma levels of cortisol (ug/dL) and ACTH (pg/ml) were assessed by chemiluminometry enzyme amplificated method. Heath-Carter anthropometric somatotype model was used to determine 13 elements of somatotype. Descriptive statistics and multiple regression were used for statistical analysis (P<0.05). Body composition and AnT were not significantly different between each time point of testing. The mesomorph-ectomorph (N.=21), balanced mesomorph (N.=8) and balanced ectomorph (N.=7) were the most frequent somatotypes. There were significant decrements of cortisol plasma levels (at rest 33.4%; after test 27.46%), with insignificant changes of ACTH plasma levels, after 6 weeks of preparation phase and after finishing of half season, at rest and after maximal treadmill test. There were significant correlation between ACTH levels at rest (R=0.44; P<0.01) and some somatotypes (mesomorph endomorph, central and balanced endomorph) and ACTH levels after maximal exercise test (R=0.36; P<0.05) and balanced ectomorph and endomorph mesomorph. There were significant correlation between cortisol levels after maximal exercise test at the beginning of training process (R=0.59; P<0.01) and some somatotypes (mesomorph ectomorph, mesomorph endomorph, balanced endomorph and endomorph mesomorph) and after the finishing of training process (R=0.62; P<0.01) and some somatotypes (central, balanced ectomorph and mesomorph ectomorph). The significant decreases of cortisol plasma levels during soccer training process could indicate a stagnation of training process, accordingly with insignificant changes of AnT. The significant correlations of some somatotypes with stress hormonal responses could only suggest that the somatotype characteristics of young soccer players could be of interest in process of selection and planning of soccer training process with an essential need for more studies.

Effects of a Special Olympics Unified Sports soccer program on psycho-social attributes of youth with and without intellectual disability.

PubMed

Özer, D; Baran, F; Aktop, A; Nalbant, S; Ağlamış, E; Hutzler, Y

2012-01-01

The purpose of the study was to investigate the effects of a Special Olympics (SO) Unified Sports (UNS) soccer program on psycho-social attributes of youth with and without intellectual disabilities (ID). Participants were 76 male youth with (n=38) and without (n=38) ID. Participants with ID were randomly allocated into a SO athletes group (n=23, mean age=14.5; SD=1.2 years) and a control group (CG) (n=15, mean age=14.5; SD=.8 years). Twenty-three randomly selected youth without ID formed the partner group (mean age=14.1; SD=.9 years) and 15 youth without ID (mean age=13.8; SD=.5 years) formed the CG. Instruments included the Friendship Activity Scale (FAS) (Siperstein, 1980), the Adjective Checklist (Siperstein, 1980), and the Children Behavior Checklist (Achenbach, 1991). The soccer training program lasted eight weeks, 1.5h per session, three times per week, in addition to school physical education (PE). The CG did not participate in any sports in addition to PE. The findings showed that the UNS program was effective in decreasing the problem behaviors of youth with ID and increasing their social competence and FAS scores. In addition, the program was found to be effective in improving the attitude of youth without disabilities toward participants with disabilities. In conclusion, the present findings demonstrate the utility of a UNS program for both youth with and without disabilities. Copyright © 2011 Elsevier Ltd. All rights reserved.

Lower limb strength in professional soccer players: profile, asymmetry, and training age.

PubMed

Fousekis, Konstantinos; Tsepis, Elias; Vagenas, George

2010-01-01

Kicking and cutting skills in soccer are clearly unilateral, require asymmetrical motor patterns and lead to the development of asymmetrical adaptations in the musculoskeletal function of the lower limbs. Assuming that these adaptations constitute a chronicity-dependent process, this study examined the effects of professional training age (PTA) on the composite strength profile of the knee and ankle joint in soccer players. One hundred soccer players (n=100) with short (5-7 years), intermediate (8-10 years) and long (>11 years) PTA were tested bilaterally for isokinetic concentric and eccentric strength of the knee and ankle muscles. Knee flexion-extension was tested concentrically at 60°, 180° and 300 °/sec and eccentrically at 60° and 180 °/sec. Ankle dorsal and plantar flexions were tested at 60 °/sec for both the concentric and eccentric mode of action. Bilaterally averaged muscle strength [(R+L)/2] increased significantly from short training age to intermediate and stabilized afterwards. These strength adaptations were mainly observed at the concentric function of knee extensors at 60°/sec (p = 0. 023), knee flexors at 60°/sec (p = 0.042) and 180°/sec (p = 0.036), and ankle plantar flexors at 60o/sec (p = 0.044). A linear trend of increase in isokinetic strength with PTA level was observed for the eccentric strength of knee flexors at 60°/sec (p = 0.02) and 180°/sec (p = 0.03). Directional (R/L) asymmetries decreased with PTA, with this being mainly expressed in the concentric function of knee flexors at 180°/sec (p = 0.04) and at 300 °/sec (p = 0.03). These findings confirm the hypothesis of asymmetry in the strength adaptations that take place at the knee and ankle joint of soccer players mainly along with short and intermediate PTA. Players with a longer PTA seem to adopt a more balanced use of their lower extremities to cope with previously developed musculoskeletal asymmetries and possibly reduce injury risk. This has certain implications regarding proper training and injury prevention in relation to professional experience in soccer. Key pointsMuscle strength increased from the low (5-7 years) to the intermediate professional training age (8-10 years) and stabilized thereafter.Soccer practicing and competition at the professional level induces critical strength adaptations (asymmetries) regarding the function of the knee and ankle musculature.Soccer players with long professional training age showed a tendency for lower isokinetic strength asymmetries than players with intermediate and short professional training age.

Assessment of the in-season changes in mechanical and neuromuscular characteristics in professional soccer players.

PubMed

García-García, Oscar; Serrano-Gómez, Virginia; Hernández-Mendo, Antonio; Tapia-Flores, Antonio

2016-06-01

The aim of this study was to monitor in-season changes in the mechanical and neuromuscular characteristics of knee extensor and flexor muscles in professional soccer players. Twenty-one professional soccer players (soccer group, or SG) and sixteen non-soccer playing males (non-soccer group, or NSG) were assessed by tensiomyography on two occasions: just after the start of the competitive season and 10 weeks later. During this time the soccer players' training sessions were built mainly on speed and strength drills. Mixed-design factorial analysis of variance was conducted and effect sizes were calculated. There was a significant interaction between time (assessment points) x group (SG vs. NSG) x muscle for contraction time (Tc), maximum radial muscle displacement (Dm), and delay time (Td). In the case of the knee extensors, after 10 weeks, there was a 17.7%-22.7% decrease in Tc, an 8.7%-9.9% decrease in Td, and a 12.2%-14.2% decrease in Dm knee extensor in the SG (P<0.01), with a large effect size. In the case of the knee flexors, by contrast, there was an 11.9% increase in Td and a 24.5% increase in Dm (P<0.01), with a moderate to large effect size. The findings confirm that mechanical and neuromuscular characteristics change over time and also vary according to the characteristics of the athlete (SG vs. NSG) and the muscle analyzed. In conclusion, soccer coaches could use Tc, Td, and Dm data to individualize work load and intensity and control the effects of neuromuscular training throughout the season using a portable, non-invasive technique that, unlike stress tests, does not cause fatigue and therefore does not interfere with training periodization.

Effects of Static Stretching and Playing Soccer on Knee Laxity.

PubMed

Baumgart, Christian; Gokeler, Alli; Donath, Lars; Hoppe, Matthias W; Freiwald, Jürgen

2015-11-01

This study investigated exercise-induced effects of static stretching and playing soccer on anterior tibial translation (ATT) of the knee joint. Randomized controlled trial. University biomechanics laboratory. Thirty-one athletes were randomly assigned into a stretching (26.9 ± 6.2 years, 1.77 ± 0.09 m, 67.9 ± 10.7 kg) and a control group (27.9 ± 7.4 years, 1.75 ± 0.08 m, 72.0 ± 14.9 kg). Thirty-one amateur soccer players in an additional soccer group (25.1 ± 5.6 years, 1.74 ± 0.10 m, 71.8 ± 14.8 kg). All participants had no history of knee injury requiring surgery and any previous knee ligament or cartilage injury. The stretching group performed 4 different static stretching exercises with a duration of 2 × 20 seconds interspersed with breaks of 10 seconds. The soccer group completed a 90-minute soccer-specific training program. The control group did not perform any physical activity for approximately 30 minutes. Anterior tibial translation was measured with the KT-1000 knee arthrometer at forces of 67 N, 89 N, and maximal manual force (Max) before and after the intervention. There was a significant increase in ATT after static stretching and playing soccer at all applied forces. Maximal manual testing revealed a mean increase of ATT after static stretching of 2.1 ± 1.6 mm (P < 0.0005) and after playing soccer of 1.0 ± 1.5 mm (P = 0.001). The ATT increase after static stretching at 67 and 89 N is significantly higher than in controls. At maximum manual testing, significant differences were evident between all groups. Static stretching and playing soccer increase ATT and may consequently influence mechanical factors of the anterior cruciate ligament. The ATT increase after static stretching was greater than after playing soccer. The observed increase in ATT after static stretching and playing soccer may be associated with changes in kinesthetic perception and sensorimotor control, activation of muscles, joint stability, overall performance, and higher injury risk.

Longitudinal predictors of aerobic performance in adolescent soccer players.

PubMed

Valente-dos-Santos, João; Coelho-e-Silva, Manuel J; Duarte, João; Figueiredo, António J; Liparotti, João R; Sherar, Lauren B; Elferink-Gemser, Marije T; Malina, Robert M

2012-01-01

The importance of aerobic performance in youth soccer is well established. The aim of the present study was to evaluate the contributions of chronological age (CA), skeletal age (SA), body size, and training to the longitudinal development of aerobic performance in youth male soccer players aged 10 to 18 years. Players (n=83) were annually followed up during 5 years, resulting in an average of 4.4 observations per player. Decimal CA was calculated, and SA, stature, body weight, and aerobic performance were measured once per year. Fat-free mass (FFM) was estimated from age- and gender-specific anthropometric formulas, and annual volume training was recorded. After testing for multicollinearity, multilevel regression modeling was used to analyze the longitudinal data aligned by CA and SA (Model 1 and 2, respectively) and to develop aerobic performance scores. The following equations provide estimations of the aerobic performance for young soccer players: ŷ(Model 1 [deviance from the null model =388.50; P<0.01]) =57.75+9.06×centered CA-0.57×centered CA(2)+0.03×annual volume training and ŷ(Model 2 [deviance from the null model=327.98; P<0.01])=13.03+4.04×centered SA-0.12×centered SA(2)+0.99×FFM+0.03×annual volume training. The development of aerobic performance in young soccer players was found to be significantly related to CA, biological development, and volume of training.

The scientific foundations and associated injury risks of early soccer specialisation.

PubMed

Read, Paul J; Oliver, Jon L; De Ste Croix, Mark B A; Myer, Gregory D; Lloyd, Rhodri S

2016-12-01

Early specialisation is characterised by formal participation in a single sport at the exclusion of others. Limited data are available to support this approach in the development of soccer players who attain elite status later in life. Of growing concern is the associated increased risk of injury and suggestions that single sport specialisation is a risk factor independent of age, growth, biological maturation and training volumes. In the United Kingdom, elite soccer organisations have recently adopted an early sport specialisation approach following the introduction of the Elite Player Performance Plan. A key tenet of this programme is increased opportunities for training through a marked rise in the specified on-pitch hours per week. The accumulation of high training hours may be less of a relevant marker for success, and the impact of such a significant increase in training volume for young athletes who are experiencing a range of growth and maturational processes is currently unknown. This critical commentary includes an evidence-based discussion of the effectiveness of early sport specialisation and the potential injury risks associated with such programmes placing a specific focus on elite male youth soccer players. Available data indicate that modifications to the existing Elite Player Performance Plan framework could enhance players' development and reduce injury risk. Proposed alterations include reduced volume of soccer-specific training at key stages of growth and maturation and guidelines for the provision of a greater variety of physical activities that are integrated within other programme components.

The scientific foundations and associated injury risks of early soccer specialisation

PubMed Central

Read, Paul J.; Oliver, Jon L.; De Ste Croix, Mark B. A.; Myer, Gregory D.; Lloyd, Rhodri S.

2017-01-01

Early specialisation is characterised by formal participation in a single sport at the exclusion of others. Limited data are available to support this approach in the development of soccer players who attain elite status later in life. Of growing concern is the associated increased risk of injury and suggestions that single sport specialisation is a risk factor independent of age, growth, biological maturation and training volumes. In the United Kingdom, elite soccer organisations have recently adopted an early sport specialisation approach following the introduction of the Elite Player Performance Plan. A key tenet of this programme is increased opportunities for training through a marked rise in the specified on-pitch hours per week. The accumulation of high training hours may be less of a relevant marker for success, and the impact of such a significant increase in training volume for young athletes who are experiencing a range of growth and maturational processes is currently unknown. This critical commentary includes an evidence-based discussion of the effectiveness of early sport specialisation and the potential injury risks associated with such programmes placing a specific focus on elite male youth soccer players. Available data indicate that modifications to the existing Elite Player Performance Plan framework could enhance players’ development and reduce injury risk. Proposed alterations include reduced volume of soccer-specific training at key stages of growth and maturation and guidelines for the provision of a greater variety of physical activities that are integrated within other programme components. PMID:27120711

Effects of Small-Sided Games vs. Interval Training in Aerobic Fitness and Physical Enjoyment in Young Elite Soccer Players

PubMed Central

Martín, Juan; Lerga, Javier; Sánchez, Felipe; Villagra, Federico; Zulueta, Javier J.

2015-01-01

The purpose of this study was to compare the effects of Small-Sided Games (SSG) vs. Interval Training (IT) in soccer training on aerobic fitness and physical enjoyment in youth elite soccer players during the last 8 weeks of the season. Seventeen U-16 male soccer players (age = 15.5 ± 0.6 years, and 8.5 years of experience) of a Spanish First Division club academy were randomized to 2 different groups for 6 weeks: SSG group (n = 9) and IT group (n = 8). In addition to the usual technical and tactical sessions and competitive games, the SSG group performed 11 sessions with different SSGs, whereas the IT group performed the same number of sessions of IT. Players were tested before and after the 6-week training intervention with a continuous maximal multistage running field test and the counter movement jump test (CMJ). At the end of the study, players answered the physical activity enjoyment scale (PACES). During the study, heart rate (HR) and session perceived effort (sRPE) were assessed. SSGs were as effective as IT in maintaining the aerobic fitness in elite young soccer players during the last weeks of the season. Players in the SSG group declared a greater physical enjoyment than IT (P = 0.006; ES = 1.86 ± 1.07). Coaches could use SSG training during the last weeks of the season as an option without fear of losing aerobic fitness while promoting high physical enjoyment. PMID:26331623

Creatine monohydrate supplementation on lower-limb muscle power in Brazilian elite soccer players.

PubMed

Claudino, João G; Mezêncio, Bruno; Amaral, Sérgio; Zanetti, Vinícius; Benatti, Fabiana; Roschel, Hamilton; Gualano, Bruno; Amadio, Alberto C; Serrão, Julio C

2014-01-01

Studies involving chronic creatine supplementation in elite soccer players are scarce. Therefore, the aim of this study was to examine the effects of creatine monohydrate supplementation on lower-limb muscle power in Brazilian elite soccer players (n = 14 males) during pre-season training. This was a randomized, double-blind, placebo-controlled parallel-group study. Brazilian professional elite soccer players participated in this study. During the pre-season (7 weeks), all the subjects underwent a standardized physical and specific soccer training. Prior to and after either creatine monohydrate or placebo supplementation, the lower-limb muscle power was measured by countermovement jump performance. The Jumping performance was compared between groups at baseline (p = 0.99). After the intervention, jumping performance was lower in the placebo group (percent change = - 0.7%; ES = - 0.3) than in the creatine group (percent change = + 2.4%; ES = + 0.1), but it did not reach statistical significance (p = 0.23 for time x group interaction). Fisher's exact test revealed that the proportion of subjects that experienced a reduction in jumping performance was significantly greater in the placebo group than in the creatine group (5 and 1, respectively; p = 0.05) after the training. The magnitude-based inferences demonstrated that placebo resulted in a possible negative effect (50%) in jumping performance, whereas creatine supplementation led to a very likely trivial effect (96%) in jumping performance in the creatine group. Creatine monohydrate supplementation prevented the decrement in lower-limb muscle power in elite soccer players during a pre-season progressive training.

Effectiveness of a stress management pilot program aimed at reducing the incidence of sports injuries in young football (soccer) players.

PubMed

Olmedilla-Zafra, Aurelio; Rubio, Victor J; Ortega, Enrique; García-Mas, Alexandre

2017-03-01

Several attempts to reduce the incidence of sport injuries using psychosocial interventions produced fruitful, although inconclusive results. This paper presents the effectiveness and implementation issues of a pilot 3-month stress-management and muscle relaxation program aimed at reducing sport injury incidence. Pre-post treatment-non treatment group comparison. The program was administered by a trained psychologist on a once-a-week, 1-h session basis. Seventy-four male soccer players from four National Youth league teams voluntarily participated. Teams were randomly assigned to either treatment/non-treatment group. Injury protocol, Self-monitoring cards, Athletes' satisfaction and commitment survey, Coaches' interview. Group main effect and Time-Group interaction effect were both statistically significant, F(1,60) = 8.30, p = 0.005, η 2 p  = 0.121, with the average number of injuries larger in the post-treatment phase of non-treatment group (p = 0.005, η 2 p  = 0.077). There was a significant decrease in the average number of injuries for the intervention group before and after implementing the program (p < 0.001, η 2 p  = 0.309). A controlled implementation of a psychosocial program was effective in reducing youth soccer sport injuries, with a high level of satisfaction and commitment from the athletes, as well as high acceptance from the coaches. Copyright © 2016 Elsevier Ltd. All rights reserved.

Injuries in Professional Male Soccer Players in the Netherlands: A Prospective Cohort Study

PubMed Central

Stubbe, Janine H.; van Beijsterveldt, Anne-Marie M. C.; van der Knaap, Sissi; Stege, Jasper; Verhagen, Evert A.; van Mechelen, Willem; Backx, Frank J. G.

2015-01-01

Context: Injuries are a major adverse event in a soccer player's career. Reducing injury incidence requires a thorough knowledge of the epidemiology of soccer injuries. Objective: To investigate the incidence and characteristics of injuries in the Dutch premier soccer league. Design: Cohort study. Setting: The Dutch premier soccer league. Patients or Other Participants: During the 2009–2010 soccer season, a total of 217 professional soccer players from 8 teams were prospectively followed. Main Outcome Measure(s): The medical staff recorded time-loss injuries, including information on injuries (ie, type, body part, duration) and exposure data for training sessions and matches. Results: A total of 286 injuries were recorded, affecting 62.7% of the players. The overall injury incidence was 6.2 injuries per 1000 player-hours, 2.8 in training sessions and 32.8 in matches. Most of the recorded injuries were acute (68.5%). Eight percent of the injuries were classified as recurrent. Injuries were most likely to be located in the lower extremities (82.9%). Injury time loss ranged from 1 to 752 days, with a median of 8 days. Knee injuries had the greatest consequences in terms of days of absence from soccer play (on average, 45 days). The most common diagnosis was muscle/tendon injury of the lower extremities (32.9%). Conclusions: Injury risk in the Dutch premier soccer league is high, especially during matches. Preventive measures should focus on the most common diagnoses, namely, muscle/tendon injuries of the lower extremities. PMID:25531144

Soccer injuries and recovery in Dutch male amateur soccer players: results of a prospective cohort study.

PubMed

van Beijsterveldt, Anne-Marie; Steffen, Kathrin; Stubbe, Janine H; Frederiks, Janet E; van de Port, Ingrid G L; Backx, Frank J G

2014-07-01

To describe characteristics of outdoor soccer injury and recovery among Dutch soccer players. Prospective cohort study. The 2009-2010 competitive season (33 weeks). Four hundred fifty-six Dutch male soccer players of 23 amateur teams. Coaches recorded individual exposure to all soccer activities. Paramedics or sports trainers collected information on the occurrence (e.g., location, type, circumstances) and consequences (eg, absenteeism, medical treatment) of injuries. In total, 424 time-loss injuries were sustained by 60% (n = 274) of the players, with 23% (n = 105) having more than 1 injury. This corresponds to an overall density of 9.6 (8.7-10.5) injuries per 1000 player hours; 3.9 (3.3-4.7) in training sessions and 20.4 (18.1-23.1) in soccer matches. Almost 30% (n = 123) of the injuries lasted for more than 1 month, 14% (n = 58) were reinjuries (causing longer absence than new injuries), and 54% (n = 230) of the injuries were given medical treatment. The most common diagnoses were muscle/tendon (38%) or joint/ligament injuries (23%) of the lower extremities. After regaining the ability to fully take part in soccer training or matches, 27.4% of the players (n = 116) still reported complaints. Two recommendations based on the above-mentioned results are (1) prevention should primarily focus on these most common diagnoses and (2) players resuming soccer activities after an injury should be given special attention to resolve the remaining complaints and to prevent reinjuries.

Biomechanical Differences of Multidirectional Jump Landings Among Female Basketball and Soccer Players.

PubMed

Taylor, Jeffrey B; Ford, Kevin R; Schmitz, Randy J; Ross, Scott E; Ackerman, Terry A; Shultz, Sandra J

2017-11-01

Taylor, JB, Ford, KR, Schmitz, RJ, Ross, SE, Ackerman, TA, and Shultz, SJ. Biomechanical differences of multidirectional jump landings among female basketball and soccer players. J Strength Cond Res 31(11): 3034-3045, 2017-Anterior cruciate ligament (ACL) injury prevention programs are less successful in basketball than soccer and may be due to distinct movement strategies that these athletes develop from sport-specific training. The purpose of this study was to identify biomechanical differences between female basketball and soccer players during multidirectional jump landings. Lower extremity biomechanics of 89 female athletes who played competitive basketball (n = 40) or soccer (n = 49) at the middle- or high-school level were analyzed with 3-dimensional motion analysis during a drop vertical jump, double- (SAG-DL) and single-leg forward jump (SAG-SL), and double- (FRONT-DL) and single-leg (FRONT-SL) lateral jump. Basketball players landed with either less hip or knee, or both hip and knee excursion during all tasks (p ≤ 0.05) except for the SAGSL task, basketball players landed with greater peak hip flexion angles (p = 0.04). The FRONT-SL task elicited the most distinct sport-specific differences, including decreased hip adduction (p < 0.001) angles, increased hip internal rotation (p = 0.003), and increased relative knee external rotation (p = 0.001) excursions in basketball players. In addition, the FRONT-SL task elicited greater forces in knee abduction (p = 0.003) and lesser forces in hip adduction (p = 0.001) and knee external rotation (p < 0.001) in basketball players. Joint energetics were different during the FRONT-DL task, as basketball players exhibited less sagittal plane energy absorption at the hip (p < 0.001) and greater hip (p < 0.001) and knee (p = 0.001) joint stiffness. Sport-specific movement strategies were identified during all jump landing tasks, such that soccer players exhibited a more protective landing strategy than basketball players, justifying future efforts toward sport-specific ACL injury prevention programs.

Soccer vs. running training effects in young adult men: which programme is more effective in improvement of body composition? Randomized controlled trial

PubMed Central

Pantelić, S; Kostić, R; Trajković, N; Sporiš, G

2015-01-01

The aims of this study were: 1) To determine the effects of a 12-week recreational soccer training programme and continuous endurance running on body composition of young adult men and 2) to determine which of these two programmes was more effective concerning body composition. Sixty-four participants completed the randomized controlled trial and were randomly assigned to one of three groups: a soccer training group (SOC; n=20), a running group (RUN; n=21) or a control group performing no physical training (CON; n=23). Training programmes for SOC and RUN lasted 12-week with 3 training sessions per week. Soccer sessions consisted of 60 min ordinary five-a-side, six-a-side or seven-a-side matches on a 30-45 m wide and 45-60 m long plastic grass pitch. Running sessions consisted of 60 min of continuous moderate intensity running at the same average heart rate as in SOC (~80% HRmax). All participants, regardless of group assignment, were tested for each of the following dependent variables: body weight, body height, body mass index, percent body fat, body fat mass, fat-free mass and total body water. In the SOC and RUN groups there was a significant decrease (p < 0.05) in body composition parameters from pre- to post-training values for all measures with the exception of fat-free mass and total body water. Body mass index, percent body fat and body fat mass did not differ between groups at baseline, but by week 12 were significantly lower (p < 0.05) in the SOC and RUN groups compared to CON. To conclude, recreational soccer training provides at least the same changes in body composition parameters as continuous running in young adult men when the training intensity is well matched. PMID:26681832

The Mental Skills Training of University Soccer Players

ERIC Educational Resources Information Center

Sadeghi, Hassan; Omar-Fauzee, Mohd-Sofian; Jamalis, Marjohan; Ab-Latif, Rozita; Cheric, Majid Chahrdah

2010-01-01

The purpose of this study is to identify the kind of mental skills training needed most by the university soccer players. Eight male university football players (aged 25 to 36) from one large university in Kuala Lumpur agreed to participate in this study. On average, they have 10 years of playing experience. All of them have signed the informed…

[Nutritional study of a third division soccer team].

PubMed

Martínez Reñón, Cristian; Sánchez Collado, Pilar

2013-01-01

To analyze the nutritional habits and attitudes of a semiprofessional soccer team. Nutritional study of 21 semiprofessional soccer players (18-35 years) by analyzing the daily energy intake and expenditure also the distribution of macro and micro-nutrients, differentiated type of day (normal, training or competition). The energy balance is negative in the three days studied (- 31%, - 38% and -31% respectively). There were significant differences in caloric intake between the day of competition, a normal day and a day of training. These differences are observed both in absolute values (2,438 kcal vs 2,127 y 2,221 kcal respectively) as referring to body weight (30.5 kcal/kg vs 27 y 28 kcal/kg respectively). Regarding macronutrient intake, the samples eat a diet with an insufficient amount of carbohydrates (328 g vs 371 and 540 g recommended in function of physical activity). There were no significant differences in the composition of micronutrients. The football players studied show a negative energy balance with a diet low in carbohydrates. This poor nutritional status may interfere with the development of their sporting performance and, ultimately, increase the risk of lesions. This implies the need for design and implementation of a diet and introducing nutritional education programs for these athletes. Copyright © AULA MEDICA EDICIONES 2013. Published by AULA MEDICA. All rights reserved.

Changes in Acceleration and Deceleration Capacity Throughout Professional Soccer Match-Play.

PubMed

Russell, Mark; Sparkes, William; Northeast, Jonny; Cook, Christian J; Love, Tom D; Bracken, Richard M; Kilduff, Liam P

2016-10-01

Russell, M, Sparkes, W, Northeast, J, Cook, CJ, Love, TD, Bracken, RM, and Kilduff, LP. Changes in acceleration and deceleration capacity throughout professional soccer match-play. J Strength Cond Res 30(10): 2839-2844, 2016-As the acceleration and deceleration demands of soccer are currently not well understood, this study aimed to profile markers of acceleration and deceleration capacity during professional soccer match-play. This within-player observational study required reserve team players from a Premier League club to wear 10-Hz Global Positioning System units throughout competitive matches played in the 2013-14 competitive season. Data are presented for players who completed 4 or more games during the season (n = 11), and variables are presented according to six 15-minute intervals (I1-6: 00:00-14:59 minutes, 15:00-29:59 minutes, 30:00-44:59 minutes, 45:00-59:59 minutes, 60:00-74:59 minutes, and 75:00-89:59 minutes, respectively). During I6, the distance covered (total, per minute, and at high intensity), number of sprints, accelerations (total and high intensity), decelerations (total and high intensity), and impacts were reduced compared with I1 (all p ≤ 0.05). The number of high-intensity impacts remained unchanged throughout match-play (p > 0.05). These findings indicate that high-intensity actions and markers of acceleration and deceleration capacity are reduced in the last 15 minutes of the normal duration of match-play. Such information can be used to increase the specificity of training programs designed for soccer players while also giving further insight in to the effects of 90 minutes of soccer-specific exercise. Interventions that seek to maintain the acceleration and deceleration capacity of players throughout the full duration of a soccer match warrant investigation.

Effect of astaxanthin supplementation on muscle damage and oxidative stress markers in elite young soccer players.

PubMed

Djordjevic, B; Baralic, I; Kotur-Stevuljevic, J; Stefanovic, A; Ivanisevic, J; Radivojevic, N; Andjelkovic, M; Dikic, N

2012-08-01

The purpose of the current study was to examine the effect of Astaxanthin (Asx) supplementation on muscle enzymes as indirect markers of muscle damage, oxidative stress markers and antioxidant response in elite young soccer players. Thirty-two male elite soccer players were randomly assigned in a double-blind fashion to Asx and placebo (P) group. After the 90 days of supplementation, the athletes performed a 2 hour acute exercise bout. Blood samples were obtained before and after 90 days of supplementation and after the exercise at the end of observational period for analysis of thiobarbituric acid-reacting substances (TBARS), advanced oxidation protein products (AOPP), superoxide anion (O2•¯), total antioxidative status (TAS), sulphydril groups (SH), superoxide-dismutase (SOD), serum creatine kinase (CK) and aspartate aminotransferase (AST). TBARS and AOPP levels did not change throughout the study. Regular training significantly increased O2•¯ levels (main training effect, P<0.01). O2•¯ concentrations increased after the soccer exercise (main exercise effect, P<0.01), but these changes reached statistical significance only in the P group (exercise x supplementation effect, P<0.05). TAS levels decreased significantly post- exercise only in P group (P<0.01). Both Asx and P groups experienced increase in total SH groups content (by 21% and 9%, respectively) and supplementation effect was marginally significant (P=0.08). Basal SOD activity significantly decreased both in P and in Asx group by the end of the study (main training effect, P<0.01). All participants showed a significant decrease in basal CK and AST activities after 90 days (main training effect, P<0.01 and P<0.001, respectively). CK and AST activities in serum significantly increased as result of soccer exercise (main exercise effect, P<0.001 and P<0.01, respectively). Postexercise CK and AST levels were significantly lower in Asx group compared to P group (P<0.05) The results of the present study suggest that soccer training and soccer exercise are associated with excessive production of free radicals and oxidative stress, which might diminish antioxidant system efficiency. Supplementation with Asx could prevent exercise induced free radical production and depletion of non-enzymatic antioxidant defense in young soccer players.

Effect of Practicing Soccer Juggling With Different Sized Balls Upon Performance, Retention, and Transfer to Ball Reception.

PubMed

Raastad, Olav; Aune, Tore Kristian; van den Tillaar, Roland

2016-10-01

The aim of this study was to investigate if making the skill acquisition phase more difficult or easier would enhance performance in soccer juggling, and if this practice has a positive intertask transfer effect to ball reception performance. Twenty-two adolescent soccer players were tested in juggling a soccer ball and in the control of an approaching ball at a pre, post and retention test. The participants were randomly divided in a small ball size and bigger ball size training group that both trained four times per week for 6 weeks. At the post and retention test both groups enhanced performance in soccer juggling test with no difference between groups and no increase in ball reception performance at these tests. It was concluded that about intra task transfer and retention of soccer juggling skills, it does not matter if you increase (small balls) or decrease the difficulty (larger balls) when using the same amount of practice time within the skill acquisition phase in soccer juggling. In addition that for ball juggling and ball reception (inter task) these two tasks differ too much in afferent information and movement characteristics that no positive transfer between these two skills no positive intertask transfer can be expected.

The Effect of Two Speed Endurance Training Regimes on Performance of Soccer Players.

PubMed

Iaia, F Marcello; Fiorenza, Matteo; Perri, Enrico; Alberti, Giampietro; Millet, Grégoire P; Bangsbo, Jens

2015-01-01

In order to better understand the specificity of training adaptations, we compared the effects of two different anaerobic training regimes on various types of soccer-related exercise performances. During the last 3 weeks of the competitive season, thirteen young male professional soccer players (age 18.5±1 yr, height 179.5±6.5 cm, body mass 74.3±6.5 kg) reduced the training volume by ~20% and replaced their habitual fitness conditioning work with either speed endurance production (SEP; n = 6) or speed endurance maintenance (SEM; n = 7) training, three times per wk. SEP training consisted of 6-8 reps of 20-s all-out running bouts followed by 2 min of passive recovery, whereas SEM training was characterized by 6-8 x 20-s all-out efforts interspersed with 40 s of passive recovery. SEP training reduced (p<0.01) the total time in a repeated sprint ability test (RSAt) by 2.5%. SEM training improved the 200-m sprint performance (from 26.59±0.70 to 26.02±0.62 s, p<0.01) and had a likely beneficial impact on the percentage decrement score of the RSA test (from 4.07±1.28 to 3.55±1.01%) but induced a very likely impairment in RSAt (from 83.81±2.37 to 84.65±2.27 s). The distance covered in the Yo-Yo Intermittent Recovery test level 2 was 10.1% (p<0.001) and 3.8% (p<0.05) higher after SEP and SEM training, respectively, with possibly greater improvements following SEP compared to SEM. No differences were observed in the 20- and 40-m sprint performances. In conclusion, these two training strategies target different determinants of soccer-related physical performance. SEP improved repeated sprint and high-intensity intermittent exercise performance, whereas SEM increased muscles' ability to maximize fatigue tolerance and maintain speed development during both repeated all-out and continuous short-duration maximal exercises. These results provide new insight into the precise nature of a stimulus necessary to improve specific types of athletic performance in trained young soccer players.

The Effect of Two Speed Endurance Training Regimes on Performance of Soccer Players

PubMed Central

Iaia, F. Marcello; Fiorenza, Matteo; Perri, Enrico; Alberti, Giampietro; Millet, Grégoire P.; Bangsbo, Jens

2015-01-01

In order to better understand the specificity of training adaptations, we compared the effects of two different anaerobic training regimes on various types of soccer-related exercise performances. During the last 3 weeks of the competitive season, thirteen young male professional soccer players (age 18.5±1 yr, height 179.5±6.5 cm, body mass 74.3±6.5 kg) reduced the training volume by ~20% and replaced their habitual fitness conditioning work with either speed endurance production (SEP; n = 6) or speed endurance maintenance (SEM; n = 7) training, three times per wk. SEP training consisted of 6–8 reps of 20-s all-out running bouts followed by 2 min of passive recovery, whereas SEM training was characterized by 6–8 x 20-s all-out efforts interspersed with 40 s of passive recovery. SEP training reduced (p<0.01) the total time in a repeated sprint ability test (RSAt) by 2.5%. SEM training improved the 200-m sprint performance (from 26.59±0.70 to 26.02±0.62 s, p<0.01) and had a likely beneficial impact on the percentage decrement score of the RSA test (from 4.07±1.28 to 3.55±1.01%) but induced a very likely impairment in RSAt (from 83.81±2.37 to 84.65±2.27 s). The distance covered in the Yo-Yo Intermittent Recovery test level 2 was 10.1% (p<0.001) and 3.8% (p<0.05) higher after SEP and SEM training, respectively, with possibly greater improvements following SEP compared to SEM. No differences were observed in the 20- and 40-m sprint performances. In conclusion, these two training strategies target different determinants of soccer-related physical performance. SEP improved repeated sprint and high-intensity intermittent exercise performance, whereas SEM increased muscles’ ability to maximize fatigue tolerance and maintain speed development during both repeated all-out and continuous short-duration maximal exercises. These results provide new insight into the precise nature of a stimulus necessary to improve specific types of athletic performance in trained young soccer players. PMID:26394225

A genetic-based algorithm for personalized resistance training

PubMed Central

Kiely, J; Suraci, B; Collins, DJ; de Lorenzo, D; Pickering, C; Grimaldi, KA

2016-01-01

Association studies have identified dozens of genetic variants linked to training responses and sport-related traits. However, no intervention studies utilizing the idea of personalised training based on athlete's genetic profile have been conducted. Here we propose an algorithm that allows achieving greater results in response to high- or low-intensity resistance training programs by predicting athlete's potential for the development of power and endurance qualities with the panel of 15 performance-associated gene polymorphisms. To develop and validate such an algorithm we performed two studies in independent cohorts of male athletes (study 1: athletes from different sports (n = 28); study 2: soccer players (n = 39)). In both studies athletes completed an eight-week high- or low-intensity resistance training program, which either matched or mismatched their individual genotype. Two variables of explosive power and aerobic fitness, as measured by the countermovement jump (CMJ) and aerobic 3-min cycle test (Aero3) were assessed pre and post 8 weeks of resistance training. In study 1, the athletes from the matched groups (i.e. high-intensity trained with power genotype or low-intensity trained with endurance genotype) significantly increased results in CMJ (P = 0.0005) and Aero3 (P = 0.0004). Whereas, athletes from the mismatched group (i.e. high-intensity trained with endurance genotype or low-intensity trained with power genotype) demonstrated non-significant improvements in CMJ (P = 0.175) and less prominent results in Aero3 (P = 0.0134). In study 2, soccer players from the matched group also demonstrated significantly greater (P < 0.0001) performance changes in both tests compared to the mismatched group. Among non- or low responders of both studies, 82% of athletes (both for CMJ and Aero3) were from the mismatched group (P < 0.0001). Our results indicate that matching the individual's genotype with the appropriate training modality leads to more effective resistance training. The developed algorithm may be used to guide individualised resistance-training interventions. PMID:27274104

n-3 Fatty Acid Supplementation During 4 Weeks of Training Leads to Improved Anaerobic Endurance Capacity, but not Maximal Strength, Speed, or Power in Soccer Players.

PubMed

Gravina, Leyre; Brown, Frankie F; Alexander, Lee; Dick, James; Bell, Gordon; Witard, Oliver C; Galloway, Stuart D R

2017-08-01

Omega-3 fatty acid (n-3 FA) supplementation could promote adaptation to soccer-specific training. We examined the impact of a 4-week period of n-3 FA supplementation during training on adaptations in 1RM knee extensor strength, 20-m sprint speed, vertical jump power, and anaerobic endurance capacity (Yo-Yo test) in competitive soccer players. Twenty six soccer players were randomly assigned to one of two groups: n-3 FA supplementation (n-3 FA; n = 13) or placebo (n = 13). Both groups performed two experimental trial days. Assessments of physical function and respiratory function were conducted pre (PRE) and post (POST) supplementation. Training session intensity, competitive games and nutritional intake were monitored during the 4-week period. No differences were observed in respiratory measurements (FEV1, FVC) between groups. No main effect of treatment was observed for 1RM knee extensor strength, explosive leg power, or 20 m sprint performance, but strength improved as a result of the training period in both groups (p < .05). Yo-Yo test distance improved with training in the n-3 FA group only (p < .01). The mean difference (95% CI) in Yo-Yo test distance completed from PRE to POST was 203 (66-340) m for n-3 FA, and 62 (-94-217) m for placebo, with a moderate effect size (Cohen's d of 0.52). We conclude that 4 weeks of n-3 FA supplementation does not improve strength, power or speed assessments in competitive soccer players. However, the increase in anaerobic endurance capacity evident only in the n-3 FA treatment group suggests an interaction that requires further study.

Ad libitum fluid intake does not prevent dehydration in suboptimally hydrated young soccer players during a training session of a summer camp.

PubMed

Arnaoutis, Giannis; Kavouras, Stavros A; Kotsis, Yiannis P; Tsekouras, Yiannis E; Makrillos, Michalis; Bardis, Costas N

2013-06-01

There is a lack of studies concerning hydration status of young athletes exercising in the heat. To assess preexercise hydration status in young soccer players during a summer sports camp and to evaluate body- water balance after soccer training sessions. Initial hydration status was assessed in 107 young male soccer players (age 11-16 yr) during the 2nd day of the camp. Seventy-two athletes agreed to be monitored during 2 more training sessions (3rd and 5th days of the camp) to calculate dehydration via changes in body weight, while water drinking was allowed ad libitum. Hydration status was assessed via urine specific gravity (USG), urine color, and changes in total body weight. Mean environmental temperature and humidity were 27.2 ± 2 °C and 57% ± 9%, respectively. According to USG values, 95 of 107 of the players were hypohydrated (USG ≥ 1.020) before practice. The prevalence of dehydration observed was maintained on both days, with 95.8% and 97.2% of the players being dehydrated after the training sessions on the 3rd and 5th days, respectively. Despite fluid availability, 54 of the 66 (81.8%) dehydrated players reduced their body weight (-0.35 ± 0.04 kg) as a response to training, while 74.6% (47 out of the 63) further reduced their body weight (-0.22 ± 0.03 kg) after training on the 5th day. Approximately 90% of the young soccer players who began exercising under warm weather conditions were hypohydrated, while drinking ad libitum during practice did not prevent further dehydration in already dehydrated players.

Effects of 12-week on-field combined strength and power training on physical performance among U-14 young soccer players.

PubMed

Wong, Pui-lam; Chamari, Karim; Wisløff, Ulrik

2010-03-01

This study examined the effects of on-field combined strength and power training (CSPT) on physical performance among U-14 young soccer players. Players were assigned to experimental (EG, n = 28) and control groups (CG, n = 23). Both groups underwent preseason soccer training for 12 weeks. EG performed CSPT twice a week, which consisted of strength and power exercises that trained the major muscles of the core, upper, and lower body. CSPT significantly (p < 0.05) improved vertical jump height, ball-shooting speed, 10 m and 30 m sprint times, Yo-Yo intermittent endurance run (YYIER), and reduced submaximal running cost (RC). CSPT had moderate effect on vertical jump, ball-shooting, 30 m sprint, and YYIER, small effect on 10 m sprint, RC, and maximal oxygen uptake. YYIER had significant (p < 0.05) correlations with 10 m (r = -0.47) and 30 m (r = -0.43) sprint times, ball-shooting speed (r = 0.51), and vertical jump (r = 0.34). The CSPT can be performed together with soccer training with no concomitant interference on aerobic capacity and with improved explosive performances. In addition, it is suggested that CSPT be performed during the preseason period rather than in-season to avoid insufficient recovery/rest or overtraining.

Effect of 8 Weeks Soccer Training on Health and Physical Performance in Untrained Women.

PubMed

Ortiz, Jaelson G; da Silva, Juliano F; Carminatti, Lorival J; Guglielmo, Luiz G A; Diefenthaeler, Fernando

2018-03-01

This study aims to analyze the physiological, neuromuscular, and biochemical responses in untrained women after eight weeks of regular participation in small-sided soccer games compared to aerobic training. Twenty-seven healthy untrained women were divided into two groups [soccer group (SG = 17) and running group (RG = 10)]. Both groups trained three times per week for eight weeks. The variables measured in this study were maximal oxygen uptake (VO 2 max), relative velocity at VO 2 max (vVO 2 max), peak velocity, relative intensity at lactate threshold (vLT), relative intensity at onset of blood lactate accumulation (vOBLA), peak force, total cholesterol, HDL, LDL, triglycerides, and cholesterol ratio (LDL/HDL). VO 2 max, vLT, and vOBLA increased significantly in both groups (12.8 and 16.7%, 11.1 and 15.3%, 11.6 and 19.8%, in SG and RG respectively). However, knee extensors peak isometric strength and triglyceride levels, total cholesterol, LDL, and HDL did not differ after eight weeks of training in both groups. On the other hand, the LDL/HDL ratio significantly reduced in both groups. In conclusion, eight weeks of regular participation in small-sided soccer games was sufficient to increase aerobic performance and promote health benefits related to similar aerobic training in untrained adult women.

Is Recreational Soccer Effective for Improving VO2max A Systematic Review and Meta-Analysis.

PubMed

Milanović, Zoran; Pantelić, Saša; Čović, Nedim; Sporiš, Goran; Krustrup, Peter

2015-09-01

Soccer is the most popular sport worldwide, with a long history and currently more than 500 million active participants, of whom 300 million are registered football club members. On the basis of scientific findings showing positive fitness and health effects of recreational soccer, FIFA (Fédération Internationale de Football Association) introduced the slogan "Playing football for 45 min twice a week-best prevention of non-communicable diseases" in 2010. The objective of this paper was to perform a systematic review and meta-analysis of the literature to determine the effects of recreational soccer on maximal oxygen uptake (VO2max). Six electronic databases (MEDLINE, PubMed, SPORTDiscus, Web of Science, CINAHL and Google Scholar) were searched for original research articles. A manual search was performed to cover the areas of recreational soccer, recreational physical activity, recreational small-sided games and VO2max using the following key terms, either singly or in combination: recreational small-sided games, recreational football, recreational soccer, street football, street soccer, effect, maximal oxygen uptake, peak oxygen uptake, cardiorespiratory fitness, VO2max. The inclusion criteria were divided into four sections: type of study, type of participants, type of interventions and type of outcome measures. Probabilistic magnitude-based inferences for meta-analysed effects were based on standardised thresholds for small, moderate and large changes (0.2, 0.6 and 1.2, respectively) derived from between-subject standard deviations for baseline fitness. Seventeen studies met the inclusion criteria and were included in the systematic review and meta-analysis. Mean differences showed that VO2max increased by 3.51 mL/kg/min (95 % CI 3.07-4.15) over a recreational soccer training programme in comparison with other training models. The meta-analysed effects of recreational soccer on VO2max compared with the controls of no exercise, continuous running and strength training were most likely largely beneficial [effect size (ES) = 1.46; 95 % confidence interval (CI) 0.91, 2.01; I (2) = 88.35 %], most likely moderately beneficial (ES = 0.68; 95 % CI 0.06, 1.29; I (2) = 69.13 %) and most likely moderately beneficial (ES = 1.08; 95 % CI -0.25, 2.42; I (2) = 71.06 %), respectively. In men and women, the meta-analysed effect was most likely largely beneficial for men (ES = 1.22) and most likely moderately beneficial for women (ES = 0.96) compared with the controls. After 12 weeks of recreational soccer with an intensity of 78-84 % maximal heart rate (HRmax), healthy untrained men improved their VO2max by 8-13 %, while untrained elderly participants improved their VO2max by 15-18 %. Soccer training for 12-70 weeks in healthy women resulted in an improvement in VO2max of 5-16 %. Significant improvements in VO2max have been observed in patients with diabetes mellitus, hypertension and prostate cancer. Recreational soccer produces large improvements in VO2max compared to strength training and no exercise, regardless of the age, sex and health status of the participants. Furthermore, recreational soccer is better than continuous endurance running, albeit the additional effect is moderate. This kind of physical activity has great potential for enhancing aerobic fitness, and for preventing and treating non-communicable diseases, and is ideal for addressing lack of motivation, a key component in physical (in)activity.

Injuries in youth amateur soccer and rugby players--comparison of incidence and characteristics.

PubMed

Junge, A; Cheung, K; Edwards, T; Dvorak, J

2004-04-01

In reviewing the literature on sports injuries, few studies could be found in which exposure related incidences of injury in different types of sport were compared. These studies indicated that ice hockey, handball, basketball, soccer, and rugby are popular team sports with a relatively high risk of injury. The aim of the study was to compare the characteristics and incidence of injuries in male youth amateur soccer and rugby players. This prospective cohort study comprised an initial baseline examination to ascertain the characteristics of the players and their level of performance, and a one season observation period during which a physician visited the team weekly and documented all occurring injuries. Twelve soccer and 10 rugby school teams with male amateur players aged 14-18 years were selected for the study. 145 soccer and 123 rugby players could be followed up over one season. Comparison of the incidence of soccer and rugby injuries indicated that rugby union football was associated with a significantly higher rate of injury than soccer. The differences were pronounced for contact injuries, injuries of the head, neck, shoulder, and upper extremity, as well as for concussion, fractures, dislocations, and strains. Rugby players incurred 1.5 times more overuse and training injuries in relation to exposure time, and 2.7 times more match injuries than soccer players. Three rugby players but no soccer players had to stop their participation in sport because of severe injury. The incidence of injury in New Zealand school teams playing soccer or rugby union is high, probably in part because of the low ratio of hours spent in training relative to hours spent playing matches. The development and implementation of preventive interventions to reduce the rate and severity of injury is recommended.

Injuries in youth amateur soccer and rugby players—comparison of incidence and characteristics

PubMed Central

Junge, A; Cheung, K; Edwards, T; Dvorak, J

2004-01-01

Objectives: In reviewing the literature on sports injuries, few studies could be found in which exposure related incidences of injury in different types of sport were compared. These studies indicated that ice hockey, handball, basketball, soccer, and rugby are popular team sports with a relatively high risk of injury. The aim of the study was to compare the characteristics and incidence of injuries in male youth amateur soccer and rugby players. Methods: This prospective cohort study comprised an initial baseline examination to ascertain the characteristics of the players and their level of performance, and a one season observation period during which a physician visited the team weekly and documented all occurring injuries. Twelve soccer and 10 rugby school teams with male amateur players aged 14–18 years were selected for the study. 145 soccer and 123 rugby players could be followed up over one season. Results: Comparison of the incidence of soccer and rugby injuries indicated that rugby union football was associated with a significantly higher rate of injury than soccer. The differences were pronounced for contact injuries, injuries of the head, neck, shoulder, and upper extremity, as well as for concussion, fractures, dislocations, and strains. Rugby players incurred 1.5 times more overuse and training injuries in relation to exposure time, and 2.7 times more match injuries than soccer players. Three rugby players but no soccer players had to stop their participation in sport because of severe injury. Conclusion: The incidence of injury in New Zealand school teams playing soccer or rugby union is high, probably in part because of the low ratio of hours spent in training relative to hours spent playing matches. The development and implementation of preventive interventions to reduce the rate and severity of injury is recommended. PMID:15039253

Effects of soccer vs swim training on bone formation in sedentary middle-aged women.

PubMed

Mohr, Magni; Helge, Eva W; Petersen, Liljan F; Lindenskov, Annika; Weihe, Pál; Mortensen, Jann; Jørgensen, Niklas R; Krustrup, Peter

2015-12-01

The present study examined the effects of 15 weeks of soccer training and two different swimming training protocols on bone turnover in sedentary middle-aged women. Eighty-three premenopausal mildly hypertensive women [age: 45 ± 6 (± SD) years, height: 165 ± 6 cm, weight: 80.0 ± 14.1 kg, body fat: 42.6 ± 5.7 %, systolic blood pressure/diastolic blood pressure: 138 ± 6/85 ± 3 mmHg] were randomized into soccer training (SOC, n = 21), high-intensity intermittent swimming (HS, n = 21), moderate-intensity swimming (MS, n = 21) intervention groups, and a control group (C, n = 20). The training groups completed three sessions per week for 15 weeks. DXA scans were performed and resting blood samples were drawn pre- and post-intervention. In SOC, plasma osteocalcin, procollagen type I N propeptide and C-terminal telopeptide increased (P < 0.05) by 37 ± 15, 52 ± 23 and 42 ± 18 %, respectively, with no changes in MS, HS and C. The intervention-induced increase in SOC was larger (P < 0.05) than in MS, HS and C. In SOC, leg BMC increased (P < 0.05) by 3.1 ± 4.5 %, with a larger increase in SOC than in C. Femoral shaft and trochanter bone mineral density (BMD) increased (P < 0.05) by 1.7 ± 1.9 and 2.4 ± 2.9 %, respectively, in SOC, with a greater (P < 0.05) change in SOC than in MS and C, whereas total body and total leg BMD did not change in any of the groups. In conclusion, 15 weeks of soccer training with sedentary middle-aged women caused marked increases in bone turnover markers, with concomitant increases in leg bone mass. No changes in bone formation and resorption markers were seen after prolonged submaximal or high-intensity intermittent swimming training. Thus, soccer training appears to provide a powerful osteogenic stimulus in middle-aged women.

Effects of Plyometric and Directional Training on Speed and Jump Performance in Elite Youth Soccer Players.

PubMed

Beato, Marco; Bianchi, Mattia; Coratella, Giuseppe; Merlini, Michele; Drust, Barry

2018-02-01

Beato, M, Bianchi, M, Coratella, G, Merlini, M, and Drust, B. Effects of plyometric and directional training on speed and jump performance in elite youth soccer players. J Strength Cond Res 32(2): 289-296, 2018-Soccer players perform approximately 1,350 activities (every 4-6 seconds), such as accelerations/decelerations and changes of direction (CODs) during matches. It is well established that COD and plyometric training have a positive impact on fitness parameters in football players. This study analyzed the effect of a complex COD and plyometric protocol (CODJ-G) compared with an isolated COD protocol (COD-G) training on elite football players. A randomized pre-post parallel group trial was used in this study. Twenty-one youth players were enrolled in this study (mean ± SD; age 17 ± 0.8 years, mass 70.1 ± 6.4 kg, and height 177.4 ± 6.2 cm). Players were randomized into 2 different groups: CODJ-G (n = 11) and COD-G (n = 10), training frequency of 2 times a week more than 6 weeks. Sprint 10, 30, and 40 m, long jump, triple hop jump, and 505 COD test were considered. Exercise-induced within-group changes in performance for both CODJ-G and COD-G: long jump (effect size [ES] = 0.32 and ES = 0.26, respectively) and sprint 10 m (ES = -0.51 and ES = -0.22, respectively), after 6 weeks of training. Moreover, CODJ-G reported substantially better results (between-group changes) in long jump test (ES = 0.32). In conclusion, this study showed that short-term protocols (CODJ-G and COD-G) are important and able to give meaningful improvements on power and speed parameters in a specific soccer population. CODJ-G showed a larger effect in sprint and jump parameters compared with COD-G after the training protocol. This study offers important implications for designing COD and jumps training in elite soccer.

Assessing the Energy Expenditure of Elite Female Soccer Players: A Preliminary Study.

PubMed

Mara, Jocelyn K; Thompson, Kevin G; Pumpa, Kate L

2015-10-01

The aim of this study was to assess the total and exercise energy expenditure of elite female soccer players during a training week. Eight elite female soccer players wore SenseWear Mini Armbands (SWAs) for 7 consecutive days during the preseason phase of a national league competition. In addition, players wore 15-Hz GPSports tracking devices during 4 training sessions and a friendly game. Total energy expenditure, exercise energy expenditure, and training and game demands were collected from the SWA and GPSports devices. Mean daily energy expenditure for the game day, training days, and rest days were 12,242 kJ (SD = 603 kJ), 11,692 (SD = 274 kJ), and 9,516 (SD = 369 kJ), respectively, with significant differences shown between activities (p < 0.001, partial η2 = 0.357), as well as between individual days (p < 0.001, partial η2 = 0.517). Mean values for energy expenditure during the friendly game (mean = 2,695 kJ, SD = 301 kJ) and training sessions (mean = 2,538 kJ, SD = 316 kJ) were similar (p = 0.278, Cohen's d = 0.5). However, there were significant differences found between individual training sessions (p = 0.001-0.035). Total and exercise energy expenditure differs throughout the week in female soccer players. Nutritional intake should be adjusted accordingly to avoid energy imbalances for optimal performance and recovery.

Using Distance Physical Education in Elite Class Soccer Referee Training: A Case Study

ERIC Educational Resources Information Center

Kizilet, Ali

2011-01-01

The objective of this study is to present a model in the framework of Distance Education (DE), which suggests that a Distance Physical Education Program (DPEP) could be applied to those who are at various ages, in various geographical locations, and are working in various professions as part-time or full-time professionals. The use of DE in…

The Effect of Immediate Post-Training Active and Passive Recovery Interventions on Anaerobic Performance and Lower Limb Flexibility in Professional Soccer Players

PubMed Central

Rey, Ezequiel; Lago-Peñas, Carlos; Casáis, Luis; Lago-Ballesteros, Joaquín

2012-01-01

The capacity to recover from intense training, competition and matches is considered an important determinant in soccer performance. At present, there is no consensus on the effect of post-training recovery interventions on subsequent training session. The aim of this study was to determine the effectiveness of active (12 min submaximal running and 8 min of static stretching) and passive recovery (20 min sitting on a bench) interventions performed immediately after a training session on anaerobic performances (CMJ, 20 m sprint and Balsom agility test) and lower limb flexibility 24 h after the training. During two experimental sessions, 31 professional soccer players participated in a randomized fully controlled trial design. The first session was designed to evaluate the player’s anaerobic performances and lower limb flexibility (pretest). After baseline measurements, participants performed a standardized soccer training during which heart rate and RPE were recorded to evaluate the training load. At the end of the training unit all players were randomly assigned to the active recovery group and the passive recovery group. A second experimental session was organized to obtain the posttest values. Players performed the same test, administered in the same order than in the first trial. No significant differences between groups were observed in heart rate and RPE. No significant effect due to recovery interventions was found on lower limb flexibility and anaerobic performances except CMJ that posttest value was significantly greater in the active recovery group than in the passive group (p < 0.05). PMID:23486836

The Effects on Soccer Passing Skills When Warming Up with Two Different Sized Soccer Balls

ERIC Educational Resources Information Center

Burcak, Keskin

2015-01-01

The purpose of the present research is studying the effects of warm-up with two different sizes of balls on passing skills. Loughborough Soccer Passing Test (LSPT) was conducted on 28 non-elite football players, who participated in the present research for 10 training days. LSPT is a passing skill protocol established on completing 16 passes…

Investigation of characteristics and risk factors of sports injuries in young soccer players: a retrospective study

PubMed Central

2013-01-01

Background The participation of children and adolescents in sports has become increasingly frequent, including soccer. This growing involvement gives rise to concerns regarding the risk of sports injuries. Therefore, the aim of the present study was to describe the musculoskeletal injuries in young soccer players. Methods 301 male soccer players with a mean age 14.67 ± 2.08 years were randomly recruited. The Referred Condition Inquiry was used to collect information on the mechanism of injury and anatomic site affected as well as personal data on the participants. The variables were analyzed based on the degree of association using Goodman’s test for contrasts between multinomial populations, with the p < 0.05. Results Among the 301 athletes, 24.25% reported at least one injury. With regard to height, taller individuals reported more injuries than shorter individuals (62.5% and 37.5%, respectively; p < 0.05). Injuries were more frequent among players with a training duration greater than five years (69.65%) in comparison to those who trained for a shorter duration (30.35%) (p < 0.05). The lower limbs, especially the ankle/foot and knee, were the most affected anatomic sites. Impact was the most common mechanism of injury. Conclusion The young practitioners of soccer analyzed had low rates of injury. The main causal mechanism was the impact. A taller height and longer exposure to training were the main risk factors for injury among young soccer players. PMID:23602027

Expression analysis of selected classes of circulating exosomal miRNAs in soccer players as an indicator of adaptation to physical activity

PubMed Central

Jastrzębski, Zbigniew; Kiszałkiewicz, Justyna; Brzeziański, Michał; Pastuszak-Lewandoska, Dorota; Radzimińki, Łukasz; Brzeziańska-Lasota, Ewa; Jegier, Anna

2017-01-01

Recently studies have shown that, depending on the type of training and its duration, the expression levels of selected circulating myomiRNAs (c-miR-27a,b, c-miR-29a,b,c, c-miR-133a) differ and correlate with the physiological indicators of adaptation to physical activity. To analyse the expression of selected classes of miRNAs in soccer players during different periods of their training cycle. The study involved 22 soccer players aged 17-18 years. The multi-stage 20-m shuttle run test was used to estimate VO2 max among the soccer players. Samples serum were collected at baseline (time point I), after one week (time point II), and after 2 months of training (time point III). The analysis of the relative quantification (RQ) level of three exosomal myomiRNAs, c-miRNA-27b, c-miR-29a, and c-miR-133, was performed by quantitative polymerase chain reaction (qPCR) at three time points – before the training, after 1 week of training and after the completion of two months of competition season training. The expression analysis showed low expression levels (according to references) of all evaluated myomiRNAs before the training cycle. Analysis performed after a week of the training cycle and after completion of the entire training cycle showed elevated expression of all tested myomiRNAs. Statistical analysis revealed significant differences between the first and the second time point in soccer players for c-miR-27b and c-miR-29a; between the first and the third time point for c-miR-27b and c-miR-29a; and between the second and the third time point for c-miR-27b. Statistical analysis showed a positive correlation between the levels of c-miR-29a and VO2 max. Two months of training affected the expression of c-miR-27b and miR-29a in soccer players. The increased expression of c-miR-27b and c-miR-29 with training could indicate their probable role in the adaptation process that takes place in the muscular system. Possibly, the expression of c-miR-29a will be found to be involved in cardiorespiratory fitness in future research. PMID:29472735

Nutrient intake and food habits of soccer players: analyzing the correlates of eating practice.

PubMed

García-Rovés, Pablo M; García-Zapico, Pedro; Patterson, Angeles M; Iglesias-Gutiérrez, Eduardo

2014-07-18

Despite the impact and popularity of soccer, and the growing field of soccer-related scientific research, little attention has been devoted to the nutritional intake and eating habits of soccer players. Moreover, the few studies that have addressed this issue suggest that the nutritional intake of soccer players is inadequate, underscoring the need for better adherence to nutritional recommendations and the development and implementation of nutrition education programs. The objective of these programs would be to promote healthy eating habits for male and female soccer players of all ages to optimize performance and provide health benefits that last beyond the end of a player's career. To date, no well-designed nutrition education program has been implemented for soccer players. The design and implementation of such an intervention requires a priori knowledge of nutritional intake and other correlates of food selection, such as food preferences and the influence of field position on nutrient intake, as well as detailed analysis of nutritional intake on match days, on which little data is available. Our aim is to provide an up-to-date overview of the nutritional intake, eating habits, and correlates of eating practice of soccer players.

Nutrient Intake and Food Habits of Soccer Players: Analyzing the Correlates of Eating Practice

PubMed Central

García-Rovés, Pablo M.; García-Zapico, Pedro; Patterson, Ángeles M.; Iglesias-Gutiérrez, Eduardo

2014-01-01

Despite the impact and popularity of soccer, and the growing field of soccer-related scientific research, little attention has been devoted to the nutritional intake and eating habits of soccer players. Moreover, the few studies that have addressed this issue suggest that the nutritional intake of soccer players is inadequate, underscoring the need for better adherence to nutritional recommendations and the development and implementation of nutrition education programs. The objective of these programs would be to promote healthy eating habits for male and female soccer players of all ages to optimize performance and provide health benefits that last beyond the end of a player’s career. To date, no well-designed nutrition education program has been implemented for soccer players. The design and implementation of such an intervention requires a priori knowledge of nutritional intake and other correlates of food selection, such as food preferences and the influence of field position on nutrient intake, as well as detailed analysis of nutritional intake on match days, on which little data is available. Our aim is to provide an up-to-date overview of the nutritional intake, eating habits, and correlates of eating practice of soccer players. PMID:25045939

Effects of recreational soccer in men with prostate cancer undergoing androgen deprivation therapy: study protocol for the ‘FC Prostate’ randomized controlled trial

PubMed Central

2013-01-01

Background Androgen deprivation therapy (ADT) is a cornerstone in the treatment of advanced prostate cancer. Adverse musculoskeletal and cardiovascular effects of ADT are widely reported and investigations into the potential of exercise to ameliorate the effects of treatment are warranted. The ‘Football Club (FC) Prostate’ study is a randomized trial comparing the effects of soccer training with standard treatment approaches on body composition, cardiovascular function, physical function parameters, glucose tolerance, bone health, and patient-reported outcomes in men undergoing ADT for prostate cancer. Methods/Design Using a single-center randomized controlled design, 80 men with histologically confirmed locally advanced or disseminated prostate cancer undergoing ADT for 6 months or more at The Copenhagen University Hospital will be enrolled on this trial. After baseline assessments eligible participants will be randomly assigned to a soccer training group or a control group receiving usual care. The soccer intervention will consist of 12 weeks of training 2–3 times/week for 45–60 min after which the assessment protocol will be repeated. Soccer training will then continue bi-weekly for an additional 20 weeks at the end of which all measures will be repeated to allow for additional analyses of long-term effects. The primary endpoint is changes in lean body mass from baseline to 12 weeks assessed by dual X-ray absorptiometry scan. Secondary endpoints include changes of cardiovascular, metabolic, and physical function parameters, as well as markers of bone metabolism and patient-reported outcomes. Discussion The FC Prostate trial will assess the safety and efficacy of a novel soccer-training approach to cancer rehabilitation on a number of clinically important health outcomes in men with advanced prostate cancer during ADT. The results may pave the way for innovative, community-based interventions in the approach to treating prostate cancer. Trial registration ClinicalTrials.gov: NCT01711892 PMID:24330570

Hematological and Biochemical Parameters in Elite Soccer Players During A Competitive Half Season

PubMed Central

Anđelković, Marija; Baralić, Ivana; Đorđević, Brižita; Stevuljević, Jelena Kotur; Radivojević, Nenad; Dikić, Nenad; Škodrić, Sanja Radojević; Stojković, Mirjana

2015-01-01

Summary Background The purpose of the present study was to report and discuss the hematological and biochemical behavior of elite soccer players, in order to get more insight in the physiological characteristics of these sportsmen and to provide trainers and sports doctors with useful indicators. Methods Nineteen male soccer players volunteered to participate in this study. We followed the young elite soccer players during a competitive half season. Venous blood samples were collected between 9:00 and 10:00 a.m. after an overnight fast (10 h) at baseline, after 45 and 90 days and hematological and biochemical parameters were measured. Results Hemoglobin and hematocrit levels were significantly reduced over the observational period (p<0.05), but erythrocyte count and iron levels remained unchanged. Bilirubin and ferritin levels significantly increased in response to regular soccer training (p<0.05). We observed a significant decrease in muscle enzyme plasma activity during the 90 days study period. ANOVA analysis revealed a significant increase in the leukocyte and neutrophil counts (p<0.05), in parallel with a significant decrease in the lymphocyte count (p<0.05) after the observational period of 90 days. Conclusions Elite soccer players are characterized by significant changes in biochemical and hematological parameters over the half season, which are linked to training workload, as well as adaptation induced by the soccer training. Although the values of the measured parameters fell within the reference range, regular monitoring of the biochemical and hematological parameters is fundamental for the identification of a healthy status and related optimal performances by sport doctors and trainers and selection of a correct workload by trainers. PMID:28356856

Risk factors associated with self-reported injury history in female youth soccer players.

PubMed

Sugimoto, Dai; Howell, David R; Tocci, Noah X; Meehan, William P

2018-04-18

studies that investigate risk factors for musculoskeletal injuries in female youth athletes are limited, especially related to training attributes and position status. to determine risk factors including training attributes and position status for a self-reported musculoskeletal injury history in female youth soccer players. we conducted a cross-sectional study of young female soccer players (mean age: 13.6 ± 2.3 years). we asked about their history of musculoskeletal injuries using an electronic questionnaire. the proportion of young female soccer players with and without a history of soccer-related musculoskeletal injuries were compared based on physical characteristics, training attributes, position status (single vs. multiple), lower extremity strength, and joint laxity. a binary logistic regression analysis was used to generate, and adjusted odds ratios adjusted for potential co-variates (aor). a 95% confidence interval (95%ci) that did not cross one or p < 0.05 were considered statistically significant. a total of 160 young female soccer players (mean age: 13.6 ± 2.3 years) participated in the study. an independent association was found between prior musculoskeletal injuries and older ages (aor: 1.60, 95%ci: 1.17, 2.20, p = 0.004), higher weight (aor: 1.10, 95%ci: 1.01, 1.20, p = 0.026), and greater bmi (aor: 1.43, 95%ci: 1.07, 1.90, p = 0.014). musculoskeletal injuries were associated with age, weight, and bmi in female youth players. the current study indicates that maintaining proper body composition may be beneficial to reduce musculoskeletal injuries among female youth soccer players.

Preseason preparation training and endothelial function in elite professional soccer players

PubMed Central

Androulakis, Nikolaos E; Koundourakis, Nikolaos E; Nioti, Eleni; Spatharaki, Paraskevi; Hatzisymeon, Despina; Miminas, Ioannis; Alexandrakis, Michael G

2015-01-01

Aim To examine whether a high volume of soccer-specific training can lead to endothelial activation and/or dysfunction in professional soccer players due to exercise-induced oxidative stress. Methods Twenty-three (15 nonsmokers and eight smokers) healthy, elite male professional soccer players (mean age: 25.2±4.3 years, BMI: 23.1±1.3 kg/m2, fat: 7.8%±2.6%) were selected for this study. All participants had a full clinical and laboratory evaluation. von Willebrand factor antigen (vWf Ag) plasma levels were measured on two different occasions: 1 day before the beginning of the preseason preparation period and after 7 weeks of strenuous exercise. Results Mean vWf Ag plasma levels were significantly decreased from 95.1%±26% to 88.3%±27.2% at the end of the experimental period (P=0.018), suggesting a potential beneficial effect on the endothelium of these athletes. Further analysis showed that age greater than 29 years with an age range from 29 to 34 years can not impair this effect (P>0.05). Conclusion Strenuous exercise did not lead to endothelium activation or dysfunction in well-trained elite soccer players. On the contrary, it seemed to produce a beneficial effect on the endothelium of these players. PMID:26648731

[Need of cardiopulmonary resuscitation training in the sport of soccer].

PubMed

Guerra-Martín, María Dolores; Martínez-Montilla, José Manuel; Amador-Marín, Bárbara

2016-01-01

In Spain there are around 25,000 cardiac arrests, many of them in the presence of non-medical personnel. In less than 25% of the cardio-respiratory arrests witnessed, witnesses began cardiopulmonary resuscitation. Soccer is a contact sport with multiple physical characteristics and requirements which pushes your body to the limit, thus leading to a higher chance of developing multiple lesions, including cardio-respiratory arrest. Therefore, our goal was to know the actual situation on training in basic life support in soccer. A literature review was performed on different databases both national (IME, CUIDEN, ENCUENTR@, ENFERMERÍA AL DÍA, ISOC) and international (PUBMED, SCOPUS, CINAHL), with different MESH descriptors related to the topic. A total of 395 references were identified. 17 studies were selected; 8 of them had like main theme cardiopulmonary resuscitation and the remaining 9 spoke on the use of semi-automatic defibrillators. There is a lack of research on this topic in soccer. This strikes our attention because in this area there could be situations requiring immediate rescue action. Therefore, we emphasize the importance of early cardio-respiratory resuscitation because training in basic life support and semi-automatic defibrillators in soccer are fundamental. Copyright © 2015 Elsevier España, S.L.U. All rights reserved.

New Tool to Control and Monitor Weighted Vest Training Load for Sprinting and Jumping in Soccer.

PubMed

Carlos-Vivas, Jorge; Freitas, Tomás T; Cuesta, Miguel; Perez-Gomez, Jorge; De Hoyo, Moisés; Alcaraz, Pedro E

2018-04-26

Carlos-Vivas, J, Freitas, TT, Cuesta, M, Perez-Gomez, J, De Hoyo, M, and Alcaraz, PE. New tool to control and monitor weighted vest training load for sprinting and jumping in soccer. J Strength Cond Res XX(X): 000-000, 2018-The purpose of this study was to develop 2 regression equations that accurately describe the relationship between weighted vest loads and performance indicators in sprinting (i.e., maximum velocity, Vmax) and jumping (i.e., maximum height, Hmax). Also, this study aimed to investigate the effects of increasing the load on spatio-temporal variables and power development in soccer players and to determine the "optimal load" for sprinting and jumping. Twenty-five semiprofessional soccer players performed the sprint test, whereas a total of 46 completed the vertical jump test. Two different regression equations were developed for calculating the load for each exercise. The following equations were obtained: % body mass (BM) = -2.0762·%Vmax + 207.99 for the sprint and % BM = -0.7156·%Hmax + 71.588 for the vertical jump. For both sprinting and jumping, when the load increased, Vmax and Hmax decreased. The "optimal load" for resisted training using weighted vest was unclear for sprinting and close to BM for vertical jump. This study presents a new tool to individualize the training load for resisted sprinting and jumping using weighted vest in soccer players and to develop the whole force-velocity spectrum according to the objectives of the different periods of the season.

Nutritional Practices of National Female Soccer Players: Analysis and Recommendations

PubMed Central

Martin, Louise; Lambeth, Anneliese; Scott, Dawn

2006-01-01

The aim of the study was to establish the nutritional practices and activity patterns of elite female soccer players. The nutritional intake of 16 female England Soccer players was self-reported over a seven-day period. Participants were provided with written and verbal guidelines for the completion of the diaries. Training details were also recorded, and used in combination with BMR predictions to calculate daily energy expenditure. Energy, macronutrient and micronutrient intakes were determined using DietMaster 4.0 software. Results suggest that energy intake was low (1904 ± 366.3 kcal) in relation to previous recommendations for soccer players. Energy expenditure (2153.5 ± 596.2 kcal) was not significantly different (p > 0.05) from intake, suggesting energy balance was achieved. Carbohydrate (53.8 ± 6.8%), protein (16.8 ± 2.1%) and fat (28.8 ± 6.6%) intakes were in line with recommendations. Fluid intake (2466 ± 1350.5ml·day-1) was sufficient to meet baseline recommendations, but would need to be higher to meet the additional requirement of training and competition. With the exception of vitamin A and iron, all micronutrient intakes were higher than the DRI. In conclusion, recommendations for female soccer players are to encourage consumption of carbohydrate-electrolyte beverages to enhance carbohydrate intake and increase fluid intake, and ensure sufficient iron rich foods are included in the diet to meet the DRI. Key points Female soccer players demonstrate a low energy intake in relation to predicted requirements, but were in energy balance in this study. Increased carbohydrate intake may be beneficial to both training and competition performance of elite female soccer players Fluid requirements should be addressed on an individual basis and matched to player requirements. The iron status of female soccer players may be compromised due to insufficient dietary intake to meet the DRV. PMID:24198690

Nutritional practices of national female soccer players: analysis and recommendations.

PubMed

Martin, Louise; Lambeth, Anneliese; Scott, Dawn

2006-01-01

The aim of the study was to establish the nutritional practices and activity patterns of elite female soccer players. The nutritional intake of 16 female England Soccer players was self-reported over a seven-day period. Participants were provided with written and verbal guidelines for the completion of the diaries. Training details were also recorded, and used in combination with BMR predictions to calculate daily energy expenditure. Energy, macronutrient and micronutrient intakes were determined using DietMaster 4.0 software. Results suggest that energy intake was low (1904 ± 366.3 kcal) in relation to previous recommendations for soccer players. Energy expenditure (2153.5 ± 596.2 kcal) was not significantly different (p > 0.05) from intake, suggesting energy balance was achieved. Carbohydrate (53.8 ± 6.8%), protein (16.8 ± 2.1%) and fat (28.8 ± 6.6%) intakes were in line with recommendations. Fluid intake (2466 ± 1350.5ml·day(-1)) was sufficient to meet baseline recommendations, but would need to be higher to meet the additional requirement of training and competition. With the exception of vitamin A and iron, all micronutrient intakes were higher than the DRI. In conclusion, recommendations for female soccer players are to encourage consumption of carbohydrate-electrolyte beverages to enhance carbohydrate intake and increase fluid intake, and ensure sufficient iron rich foods are included in the diet to meet the DRI. Key pointsFemale soccer players demonstrate a low energy intake in relation to predicted requirements, but were in energy balance in this study.Increased carbohydrate intake may be beneficial to both training and competition performance of elite female soccer playersFluid requirements should be addressed on an individual basis and matched to player requirements.The iron status of female soccer players may be compromised due to insufficient dietary intake to meet the DRV.

Evaluation of Functional Limitations in Female Soccer Players and Their Relationship with Sports Level – A Cross Sectional Study

PubMed Central

Grygorowicz, Monika; Piontek, Tomasz; Dudzinski, Witold

2013-01-01

The main objective(s) of the study The aim of this study was to analyze: a) abnormalities in the length of lower limb muscles, b) the correctness of movement patterns, and c) the impact of functional limitations of muscles on the correctness of fundamental movement patterns in a group of female soccer players, in relation to their skill level. Materials and Methods 21 female soccer players from Polish Ekstraklasa and 22 players from the 1st Division were tested for lower limb muscle length restrictions and level of fundamental movement skills (with the Fundamental Movement Screen™ test concept by Gray Cook). Chi-square test was used for categorical unrelated variables. Differences between groups in absolute point values were analyzed using the non-parametric Mann-Whitney U test. Statistical significance was set at p<0.05. Results Statistically significant higher number of measurements indicating an abnormal length of rectus femoris was observed in the 1st Division group (p = 0.0433). In the group of Ekstraklasa the authors obtained a significantly higher number of abnormal hamstring test results (p = 0.0006). Ekstraklasa players scored higher in the rotational stability test of the trunk (p = 0.0008), whereas the 1st Division players scored higher in the following tests: deep squat (p = 0.0220), in-line lunge (p = 0.0042) and active straight leg raise (p = 0.0125). The results suggest that there are different functional reasons affecting point values obtained in the FMS™ tests in both analyzed groups. Conclusions The differences in the flexibility of rectus femoris and hamstring muscle observed between female soccer players with different levels of training, may result from a long-term impact of soccer training on the muscle-tendon system and articular structures. Different causes of abnormalities in fundamental movement patterns in both analyzed groups suggest the need for tailoring prevention programs to the level of sport skills represented by the players. PMID:23825579

Short- or long-rest intervals during repeated-sprint training in soccer?

PubMed

Iaia, F Marcello; Fiorenza, Matteo; Larghi, Luca; Alberti, Giampietro; Millet, Grégoire P; Girard, Olivier

2017-01-01

The present study compared the effects of two repeated-sprint training (RST) programs, differing in duration of the between-sprint rest intervals, on various soccer-related exercise performances. For 5 weeks during the competitive season, twenty-nine young trained male soccer players either replaced two of their habitual fitness conditioning sessions with RST characterized by short (5-15; n = 9) or long (5-30; n = 10) rest intervals, or served as control (n = 10). The 5-15 and 5-30 protocols consisted of 6 repetitions of 30-m (~5 s) straight-line sprints interspersed with 15 s or 30 s of passive recovery, respectively. 5-15 improved 200-m sprint time (2.0±1.5%; p<0.05) and had a likely positive impact on 20-m sprint performance, whereas 5-30 lowered the 20-m sprint time (2.7±1.6%; p<0.05) but was only possibly effective for enhancing the 200-m sprint performance. The distance covered during the Yo-Yo Intermittent Recovery Test Level 2 increased following 5-15 (11.4±5.0%; p<0.05), which was possibly better than the non-significant 6.5% enhancement observed in 5-30. Improvements in the total time of a repeated-sprint ability test were possibly greater following 5-30 (3.6±0.9%; p<0.05) compared to 5-15 (2.6±1.1%; p<0.05). Both RST interventions led to similar beneficial (p<0.05) reductions in the percentage decrement score (~30%) of the repeated-sprint ability test as well as in blood lactate concentration during submaximal exercise (17-18%). No changes occurred in the control group. In soccer players, RST over a 5-week in-season period is an efficient means to simultaneously develop different components of fitness relevant to match performance, with different benefits induced by shorter compared to longer rest intervals.

Short- or long-rest intervals during repeated-sprint training in soccer?

PubMed Central

Iaia, F. Marcello; Fiorenza, Matteo; Larghi, Luca; Alberti, Giampietro; Millet, Grégoire P.; Girard, Olivier

2017-01-01

The present study compared the effects of two repeated-sprint training (RST) programs, differing in duration of the between-sprint rest intervals, on various soccer-related exercise performances. For 5 weeks during the competitive season, twenty-nine young trained male soccer players either replaced two of their habitual fitness conditioning sessions with RST characterized by short (5–15; n = 9) or long (5–30; n = 10) rest intervals, or served as control (n = 10). The 5–15 and 5–30 protocols consisted of 6 repetitions of 30-m (~5 s) straight-line sprints interspersed with 15 s or 30 s of passive recovery, respectively. 5–15 improved 200-m sprint time (2.0±1.5%; p<0.05) and had a likely positive impact on 20-m sprint performance, whereas 5–30 lowered the 20-m sprint time (2.7±1.6%; p<0.05) but was only possibly effective for enhancing the 200-m sprint performance. The distance covered during the Yo-Yo Intermittent Recovery Test Level 2 increased following 5–15 (11.4±5.0%; p<0.05), which was possibly better than the non-significant 6.5% enhancement observed in 5–30. Improvements in the total time of a repeated-sprint ability test were possibly greater following 5–30 (3.6±0.9%; p<0.05) compared to 5–15 (2.6±1.1%; p<0.05). Both RST interventions led to similar beneficial (p<0.05) reductions in the percentage decrement score (~30%) of the repeated-sprint ability test as well as in blood lactate concentration during submaximal exercise (17–18%). No changes occurred in the control group. In soccer players, RST over a 5-week in-season period is an efficient means to simultaneously develop different components of fitness relevant to match performance, with different benefits induced by shorter compared to longer rest intervals. PMID:28199402

Effects of knee injury primary prevention programs on anterior cruciate ligament injury rates in female athletes in different sports: a systematic review.

PubMed

Michaelidis, Michael; Koumantakis, George A

2014-08-01

Anterior Cruciate Ligament (ACL) injury is frequently encountered in sports. To analyze the effects of ACL injury prevention programs on injury rates in female athletes between different sports. A comprehensive literature search was performed in September 2012 using Pubmed Central, Science Direct, CINAHL, PEDro, Cochrane Library, SCOPUS, SPORTDiscus. The key words used were: 'anterior cruciate ligament', 'ACL', 'knee joint', 'knee injuries', 'female', 'athletes', 'neuromuscular', 'training', 'prevention'. The inclusion criteria applied were: (1) ACL injury prevention training programs for female athletes; (2) Athlete-exposure data reporting; (3) Effect of training on ACL incidence rates for female athletes. 13 studies met the inclusion criteria. Three training programs in soccer and one in handball led to reduced ACL injury incidence. In basketball no effective training intervention was found. In season training was more effective than preseason in ACL injury prevention. A combination of strength training, plyometrics, balance training, technique monitoring with feedback, produced the most favorable results. Comparing the main components of ACL injury prevention programs for female athletes, some sports-dependent training specificity issues may need addressing in future studies, related primarily to the individual biomechanics of each sport but also their most effective method of delivery. Copyright © 2013 Elsevier Ltd. All rights reserved.

Muscle adaptations and performance enhancements of soccer training for untrained men.

PubMed

Krustrup, Peter; Christensen, Jesper F; Randers, Morten B; Pedersen, Henrik; Sundstrup, Emil; Jakobsen, Markus D; Krustrup, Birgitte R; Nielsen, Jens J; Suetta, Charlotte; Nybo, Lars; Bangsbo, Jens

2010-04-01

We examined the physical demands of small-sided soccer games in untrained middle-age males and muscle adaptations and performance effects over 12 weeks of recreational soccer training in comparison with continuous running. Thirty-eight healthy subjects (20-43 years) were randomized into a soccer (SO), running (RU) and control (CO) group. Two-three weekly 1-h training sessions were performed. Muscle lactate (30.1 +/- 4.1 vs. 15.6 +/- 3.3 mmol/kg d.w.), blood lactate, blood glucose and time above 90% HR(max) (20 +/- 4% vs. 1 +/- 1%) were higher (p < 0.05) during training in SO than in RU. After 12 weeks of training, quadriceps muscle mass and mean muscle fibre area were 9 and 15% larger (p < 0.05) in SO, but unaltered in RU, and in SO, the fraction of FTx fibres was lowered (10.7 +/- 1.8 vs. 17.9 +/- 3.2%). In SO, citrate synthase activity was 10 and 14% higher (p < 0.05) after 4 and 12 weeks, but unaltered in RU. After 4 weeks VO(2max) and Yo-Yo IE2 performance were elevated (p < 0.05) to a similar extent in SO (7 and 37%) and RU (6 and 36%) but increased further (p < 0.05) from 4 to 12 weeks in SO (6 and 23%). In SO, 30-m sprint performance was improved (p < 0.05) by 0.11 +/- 0.02 s. Blood lactate during running at 11 km/h was lowered (p < 0.05) from 0 to 4 and 4 to 12 weeks (2.6 +/- 0.3 vs. 3.8 +/- 0.6 vs. 6.1 +/- 0.9 mM) and from 0 to 12 weeks in RU. No changes occurred for CO. In conclusion, recreational soccer organized as small-sided games stimulates both aerobic and anaerobic energy turnover and is an effective type of training leading to significant cardiovascular and muscular adaptations as well as performance enhancements throughout a 12-week training period.

Soccer training improves cardiac function in men with type 2 diabetes.

PubMed

Schmidt, Jakob Friis; Andersen, Thomas Rostgaard; Horton, Joshua; Brix, Jonathan; Tarnow, Lise; Krustrup, Peter; Andersen, Lars Juel; Bangsbo, Jens; Hansen, Peter Riis

2013-12-01

Patients with type 2 diabetes mellitus (T2DM) have an increased risk of cardiovascular disease, which is worsened by physical inactivity. Subclinical myocardial dysfunction is associated with increased risk of heart failure and impaired prognosis in T2DM; however, it is not clear if exercise training can counteract the early signs of diabetic heart disease. This study aimed to evaluate the effects of soccer training on cardiac function, exercise capacity, and blood pressure in middle-age men with T2DM. Twenty-one men age 49.8 ± 1.7 yr with T2DM and no history of cardiovascular disease participated in a soccer training group (n = 12) that trained 1 h twice a week or a control group (n = 9) with no change in lifestyle. Examinations included comprehensive transthoracic echocardiography, measurements of blood pressure, maximal oxygen consumption (V(˙)O(2max)), and intermittent endurance capacity before and after 12 and 24 wk. Two-way repeated-measures ANOVA was applied. After 24 wk of soccer training, left ventricular (LV) end-diastolic diameter and volume were increased (P < 0.001) compared to baseline. LV longitudinal systolic displacement was augmented by 23% (P < 0.001) and global longitudinal two-dimensional strain increased by 10% (P < 0.05). LV diastolic function, determined by mitral inflow (E/A ratio) and peak diastolic velocity E', was increased by 18% (P < 0.01) and 29% (P < 0.001), respectively, whereas LV filling pressure E/E' was reduced by 15% (P = 0.05). Systolic, diastolic, and mean arterial pressures were all reduced by 8 mm Hg (P < 0.01, P < 0.001, and P < 0.001, respectively). V(˙)O(2max) and intermittent endurance capacity was 12% and 42% (P < 0.001) higher, respectively. No changes in any of the measured parameters were observed in control group. Regular soccer training improves cardiac function, increases exercise capacity, and lowers blood pressure in men with T2DM.

Return to Training and Playing After Acute Lisfranc Injuries in Elite Professional Soccer and Rugby Players.

PubMed

Deol, Rupinderbir Singh; Roche, Andrew; Calder, James D F

2016-01-01

Lisfranc joint injuries are increasingly recognized in elite soccer and rugby players. Currently, no evidence-based guidelines exist on time frames for return to training and competition after surgical treatment. To assess the time to return to training and playing after Lisfranc joint injuries. Case series; Level of evidence, 4. A consecutive series of 17 professional soccer and rugby players in the English Premier/Championship leagues was assessed using prospectively collected data. All were isolated injuries sustained during training or competitive matches. Each player had clinical and radiological evidence of an unstable Lisfranc injury and required surgical treatment. A standardized postoperative regimen was used. The minimum follow-up time was 2 years. Clinical and radiological follow-up was obtained in all 17 players. Seven players had primarily ligamentous injuries, and 10 had bony injuries. The time from injury to fixation ranged from 8 to 31 days, and hardware was removed at 16 weeks postoperatively. One athlete retired after a ligamentous injury; the remaining 16 players returned to training and full competition. Excluding the retired player, the mean time to return to training was 20.1 weeks (range, 18-24 weeks) and to full competition was 25.3 weeks (range, 21-31 weeks). There was a significant difference between the mean time to return to competition for rugby (27.8 weeks) and soccer players (24.1 weeks; P = .02) and for ligamentous (22.5 weeks) compared with bony injuries (26.9 weeks; P = .003). Three patients suffered deep peroneal nerve sensation loss, from which 1 patient did not fully recover. Return to competitive elite-level soccer and rugby is possible after surgically treated Lisfranc injuries. Return to training can take up to 24 weeks and return to playing up to 31 weeks, with bony injuries taking longer. © 2015 The Author(s).

Effects of Ramadan Fasting on Body Composition, Aerobic Performance and Lactate, Heart Rate and Perceptual Responses in Young Soccer Players

PubMed Central

Güvenç, Alpay

2011-01-01

The purpose of this study was to examine the effects of Ramadan fasting on body composition, aerobic exercise performance and blood lactate, heart rate and perceived exertion in regularly trained young soccer players. Sixteen male soccer players participated in this study. Mean age, stature, body mass and training age of the players were 17.4±1.2 years, 175.4±3.6 cm, 69.6±4.3 kg and 5.1±1.3 years, respectively. During the Ramadan period, all subjects voluntarily chose to follow the fasting guidelines and abstained from eating and drinking from sunrise to sunset. Body composition, hydration status, dietary intake and sleep duration were assessed on four occasions: before Ramadan, at the beginning of Ramadan, at the end of Ramadan and 2 weeks after the end of Ramadan. On each occasion, aerobic exercise performance and blood lactate, heart rate and rating of perceived exertion responses of players were also determined during an incremental running test. Repeated measures of ANOVA revealed that body mass, percentage of body fat, fat-free mass, hydration status, daily sleeping time and daily energy and macronutrient intake of players did not vary significantly throughout the study period (p>0.05). However, players experienced a small but significant decrease in skinfold thicknesses over the course of the study (p<0.05). Although ratings of perceived exertion at submaximal workloads increased during Ramadan (p<0.05), blood lactate and heart rate responses had decreased by the end of Ramadan (p<0.05). In line with these changes, peak running performance and running velocity at anaerobic threshold also improved by the end of Ramadan (p<0.05). Improvements in aerobic exercise performance with time were probably due to the effects of pre-season training program that was performed after the break of the fast (Iftar) during the month of Ramadan. The results of the present study suggest that if regular training regimen, body fluid balance, daily energy intake and sleep duration are maintained as before Ramadan, Ramadan fasting does not have detrimental effects on aerobic exercise performance or body composition in young soccer players. PMID:23486092

Effects of ramadan fasting on body composition, aerobic performance and lactate, heart rate and perceptual responses in young soccer players.

PubMed

Güvenç, Alpay

2011-09-01

The purpose of this study was to examine the effects of Ramadan fasting on body composition, aerobic exercise performance and blood lactate, heart rate and perceived exertion in regularly trained young soccer players. Sixteen male soccer players participated in this study. Mean age, stature, body mass and training age of the players were 17.4±1.2 years, 175.4±3.6 cm, 69.6±4.3 kg and 5.1±1.3 years, respectively. During the Ramadan period, all subjects voluntarily chose to follow the fasting guidelines and abstained from eating and drinking from sunrise to sunset. Body composition, hydration status, dietary intake and sleep duration were assessed on four occasions: before Ramadan, at the beginning of Ramadan, at the end of Ramadan and 2 weeks after the end of Ramadan. On each occasion, aerobic exercise performance and blood lactate, heart rate and rating of perceived exertion responses of players were also determined during an incremental running test. Repeated measures of ANOVA revealed that body mass, percentage of body fat, fat-free mass, hydration status, daily sleeping time and daily energy and macronutrient intake of players did not vary significantly throughout the study period (p>0.05). However, players experienced a small but significant decrease in skinfold thicknesses over the course of the study (p<0.05). Although ratings of perceived exertion at submaximal workloads increased during Ramadan (p<0.05), blood lactate and heart rate responses had decreased by the end of Ramadan (p<0.05). In line with these changes, peak running performance and running velocity at anaerobic threshold also improved by the end of Ramadan (p<0.05). Improvements in aerobic exercise performance with time were probably due to the effects of pre-season training program that was performed after the break of the fast (Iftar) during the month of Ramadan. The results of the present study suggest that if regular training regimen, body fluid balance, daily energy intake and sleep duration are maintained as before Ramadan, Ramadan fasting does not have detrimental effects on aerobic exercise performance or body composition in young soccer players.

The effect of 8-week plyometric training on leg power, jump and sprint performance in female soccer players.

PubMed

Ozbar, Nurper; Ates, Seda; Agopyan, Ani

2014-10-01

The aim of this study was to determine the effect of 8-week plyometric training (PT) on the leg power and jump and sprint performance in female soccer players. Eighteen female soccer players from Women Second League (age = 18.2 ± 2.3 years, height = 161.3 ± 5.4 cm, body mass = 56.6 ± 7.2 kg) were randomly assigned to control (n = 9) and plyometric (n = 9) groups. Both groups continued together with regular technical and tactical soccer training for 4 days a week. Additionally, the plyometric group underwent PT for 8 weeks, 1 day per week, 60-minute session duration. During the 8-week period, the control group was hindered from any additional conditioning training. All players' jumps (triple hop, countermovement jump, and standing broad jump), running speed (20 m), and peak power were evaluated before and after 8 weeks. No significant difference was found between the groups at pretest variables (p > 0.05). Significant improvements were found in the posttest of both the groups (p ≤ 0.05), except for 20-m sprint test in the control group (p > 0.05). Triple hop distance, countermovement jump, standing broad jump, peak power, and 20-m sprint test values were all significantly improved in the plyometric group, compared with the control group (p ≤ 0.05). We concluded that short duration PT is an improved important component of athletic performance in female soccer players. The results indicate that safe, effective, and alternative PT can be useful to strength and conditioning coaches, especially during competition season where less time is available for training.

Injury incidence in a Premier League youth soccer academy using the consensus statement: a prospective cohort study

PubMed Central

Renshaw, Andrew

2016-01-01

Background There is an established risk of injury to young athletes exposed to high training loads. Identifying and monitoring injury risk is essential to aid prevention. The aim of this study was to use the consensus statement to determine the incidence and pattern of injury in 1 English Premier League soccer academy during 1 season. Methods A prospective cohort study included 181 elite academy soccer players during the 2012–2013 season. Players were divided into 5 age groups between 9 and 18 years. The number, type and incidence of injuries were recorded during matches and training. Incidence was calculated per 1000 hours of exposure. Results 127 injuries occurred during 29 346 hours of soccer exposure. 72% of injuries were non-contact related. Under (U)18 players sustained the highest number of match injuries. U12–14 players sustained the highest number of training injuries and injuries overall. U16 players sustained the highest number of severe injuries, and U18 players sustained the highest number of moderate injuries. U18 players sustained the highest number of injuries/1000 hours of training and overall. U15 players sustained the highest number of injuries/1000 hours of matches, the highest number of recurrent injuries and the highest incidence of recurrence. The most common injuries were muscle injuries in U15 and U18 players. The most common injury location was the anterior thigh, with the majority of these occurring in training. Conclusions Using the consensus statement, this study used a repeatable method to identify the injury profile of elite academy-level soccer players. PMID:27900186

Girls' soccer performance and motivation: games vs technique approach.

PubMed

Chatzopoulos, Dimitris; Drakou, Amalia; Kotzamanidou, Marina; Tsorbatzoudis, Haralambos

2006-10-01

The purpose of this study was to investigate the effects of the Technique and Games approaches on girls' soccer performance and motivation. The Technique approach focuses on technique instruction using drills, whereas the Games approach places emphasis on tactic instruction with modified games. 37 girls, 12 to 13 years old, were taught 15 soccer lessons by the Technique approach and 35 girls by the Games approach. At the beginning and at the end of the research soccer matches were videotaped and evaluated by Oslin, Mitchell, and Griffin's Game Performance Assessment Instrument. Girls' motivation was assessed on the Intrinsic Motivation Inventory. The Games group had significantly better scores after training on tactical behaviour and intrinsic motivation than the Technique group. There were no significant differences in skill execution between groups trained under the two approaches. Considering the importance of intrinsic motivation for a lifelong, physically active lifestyle, researchers could focus study on the approaches and girls' motivation.

High-density lipoprotein cholesterol subfractions and lecithin: cholesterol acyltransferase activity in collegiate soccer players.

PubMed

Imamura, H; Nagata, A; Oshikata, R; Yoshimura, Y; Miyamoto, N; Miyahara, K; Oda, K; Iide, K

2013-05-01

Many of the published data on the lipid profile of athletes is based on studies of endurance athletes. The data on soccer players are rare. The purpose of this study was to examine serum high-density lipoprotein cholesterol subfractions and lecithin:cholesterol acyltransferase activity in collegiate soccer players. 31 well-trained male collegiate soccer players were divided into 2 groups: 16 defenders and 15 offenders. They were compared with 16 sedentary controls. Dietary information was obtained with a food frequency questionnaire. The subjects were all non-smokers and were not taking any drug known to affect the lipid and lipoprotein metabolism. The offenders had significantly higher high-density lipoprotein cholesterol, high-density lipoprotein2 cholesterol, and apolipoprotein A-I than the defenders and controls, whereas the defenders had the significantly higher high-density lipoprotein2 cholesterol than the controls. Both groups of athletes had significantly higher lecithin:cholesterol acyltransferase activity than the controls. The results indicate that favorable lipid and lipoprotein profile could be obtained by vigorous soccer training. © Georg Thieme Verlag KG Stuttgart · New York.

Effects of lower extremity injuries on aerobic exercise capacity, anaerobic power, and knee isokinetic muscular function in high school soccer players.

PubMed

Ko, Kwang-Jun; Ha, Gi-Chul; Kim, Dong-Woo; Kang, Seol-Jung

2017-10-01

[Purpose] The study investigated the effects of lower extremity injuries on aerobic exercise capacity, anaerobic power, and knee isokinetic muscular function in high school soccer players. [Subjects and Methods] The study assessed U High School soccer players (n=40) in S area, South Korea, divided into 2 groups: a lower extremity injury group (n=16) comprising those with knee and ankle injuries and a control group (n=24) without injury. Aerobic exercise capacity, anaerobic power, and knee isokinetic muscular function were compared and analyzed. [Results] Regarding the aerobic exercise capacity test, significant differences were observed in maximal oxygen uptake and anaerobic threshold between both groups. For the anaerobic power test, no significant difference was observed in peak power and average power between the groups; however, a significant difference in fatigue index was noted. Regarding the knee isokinetic muscular test, no significant difference was noted in knee flexion, extension, and flexion/extension ratio between both groups. [Conclusion] Lower extremity injury was associated with reduced aerobic exercise capacity and a higher fatigue index with respect to anaerobic exercise capacity. Therefore, it seems necessary to establish post-injury training programs that improve aerobic and anaerobic exercise capacity for soccer players who experience lower extremity injury.

Physiological Characteristics of Incoming Freshmen Field Players in a Men’s Division I Collegiate Soccer Team

PubMed Central

Lockie, Robert G.; Davis, DeShaun L.; Birmingham-Babauta, Samantha A.; Beiley, Megan D.; Hurley, Jillian M.; Stage, Alyssa A.; Stokes, John J.; Tomita, Tricia M.; Torne, Ibett A.; Lazar, Adrina

2016-01-01

Freshmen college soccer players will have lower training ages than their experienced teammates (sophomores, juniors, seniors). How this is reflected in field test performance is not known. Freshmen (n = 7) and experienced (n = 10) male field soccer players from the same Division I school completed soccer-specific tests to identify potential differences in incoming freshmen. Testing included: vertical jump (VJ), standing broad jump, and triple hop (TH); 30-m sprint, (0–5, 5–10, 0–10, and 0–30 m intervals); 505 change-of-direction test; Yo-Yo Intermittent Recovery Test Level 2 (YYIRT2); and 6 × 30-m sprints to measure repeated-sprint ability. A MANOVA with Bonferroni post hoc was conducted on the performance test data, and effect sizes and z-scores were calculated from the results for magnitude-based inference. There were no significant between-group differences in the performance tests. There were moderate effects for the differences in VJ height, left-leg TH, 0–5, 0–10 and 0–30 m sprint intervals, and YYIRT2 (d = 0.63–1.18), with experienced players being superior. According to z-score data, freshmen had meaningful differences below the squad mean in the 30-m sprint, YYIRT2, and jump tests. Freshmen soccer players may need to develop linear speed, high-intensity running, and jump performance upon entering a collegiate program. PMID:29910282

Virtual gait training for children with cerebral palsy using the Lokomat gait orthosis.

PubMed

Koenig, Alexander; Wellner, Mathias; Köneke, Susan; Meyer-Heim, Andreas; Lünenburger, Lars; Riener, Robert

2008-01-01

The Lokomat gait orthosis was developed in the Spinal Cord Injury Center at the University Hospital Balgrist Zurich and provides automatic gait training for patients with neurological gait impairments, such as Cerebral Palsy (CP). Each patient undergoes a task-oriented Lokomat rehabilitation training program via a virtual reality setup. In four virtual scenarios, the patient is able to exercise tasks such as wading through water, playing soccer, overstepping obstacles or training in a street scenario, each task offering varying levels of difficulty. Patients provided positive feedback in reference to the utilized haptic method, specifically addressing the sufficient degree of realism. In a single case study, we verified the task difficulty.

[Cruciate ligament injuries under gender aspects].

PubMed

Grabau, D E; Vitzthum, K; Mache, S; Groneberg, D A; Quarcoo, D

2011-12-01

An injury of cruciate ligament is one the most common knee injuries. This accident happens mostly without external impact and towards the end of training and competition sessions. Women, especially athletes playing team sports ball games such as soccer or disciplines such as tennis, are affected 2 to 8 times more often than men. Anatomic, biomechanical and endocrinological differences are currently discussed as potential risk factors. In terms of prevention, biomechanical impact is of greatest importance given its influenceability through various training opportunities. Training programs including endurance aspects, strengthening knee musculature, balance as well as plyometric trainings were most effective. Further studies should focus more on concomitants of course of injuries. © Georg Thieme Verlag KG Stuttgart · New York.

Vitamin C and E Supplementation Effects in Professional Soccer Players Under Regular Training

PubMed Central

Zoppi, Claudio C; Hohl, Rodrigo; Silva, Fernando C; Lazarim, Fernanda L; Neto, Joaquim MF Antunes; Stancanneli, Mirtes; Macedo, Denise V

2006-01-01

Exercise training is known to induce an increase in free radical production potentially leading to enhanced muscle injury. Vitamins C and E are well known antioxidants that may prevent muscle cell damage. The purpose of this study was to determine the effects of these supplemental antioxidant vitamins on markers of oxidative stress, muscle damage and performance of elite soccer players. Ten male young soccer players were divided into two groups. Supplementation group (n = 5) received vitamins C and E supplementation daily during the pre-competitive season (S group), while the placebo group (PL group, n = 5) received a pill containing maltodextrin. Both groups performed the same training load during the three-month pre-season training period. Erythrocyte antioxidant enzymes glutathione reductase, catalase and plasma carbonyl derivatives did not show any significant variation among the experimental groups. Similarly, fitness level markers did not differ among the experimental groups. However, S group demonstrated lower lipid peroxidation and muscle damage levels (p < 0.05) compared to PL group at the final phase of pre-competitive season. In conclusion, our data demonstrated that vitamin C and E supplementation in soccer players may reduce lipid peroxidation and muscle damage during high intensity efforts, but did not enhance performance. PMID:18500971

The within-participant correlation between perception of effort and heart rate-based estimations of training load in elite soccer players.

PubMed

Kelly, David M; Strudwick, Anthony J; Atkinson, Greg; Drust, Barry; Gregson, Warren

2016-07-01

The measurement of relative physiological stress during training is important because this is the stimulus for the long-term adaptive response. Measurements of perceived exertion (RPE) have been reported to correlate with the heart rate during field-based training sessions. Nevertheless, there are few studies on how well RPE tracks with the heart rate over repeated training sessions in elite soccer players. Therefore, we aimed to quantify the within-participant correlations between variability in session-RPE (sRPE) and the heart rate in elite male soccer players, and to determine whether the playing position moderated these correlations. The field-based training of four central defenders, four wide defenders, six central midfielders, two wide midfielders and three attackers from an elite English Premier League squad were monitored over an entire in-season competitive period, giving a total of 1010 individual training sessions for study. Correlations between session-RPE and heart rates were quantified using a within-participant model. The correlation between changes in sRPE and heart rates was r = 0.75 (95% CI: 0.71-0.78). This correlation remained high across the various player positions (wide-defender, r = 0.81; central-defender, r = 0.74; wide midfielder, r = 0.70; central midfielder, r = 0.70; attacker, r = 0.84; P < 0.001). The correlation between changes in RPE and heart rates, measured during a season-long period of field-based training, is high in a sample of elite soccer players.

EFFECTS OF TWO TYPES OF TRUNK EXERCISES ON BALANCE AND ATHLETIC PERFORMANCE IN YOUTH SOCCER PLAYERS

PubMed Central

Kaneoka, Koji; Okubo, Yu; Shiraki, Hitoshi

2014-01-01

Purpose/Background: Many athletes perform trunk stabilization exercises (SE) and conventional trunk exercises (CE) to enhance trunk stability and strength. However, evidence regarding the specific training effects of SE and CE is lacking and there have been no studies for youth athletes. Therefore, the purpose of this study was to investigate the training effects of SE and CE on balance and athletic performance in youth soccer players. Methods: Twenty‐seven male youth soccer players were assigned randomly to either an SE group (n = 13) or CE group (n = 14). Data from nineteen players who completed all training sessions were used for statistical analyses (SE, n = 10; CE, n = 9). Before and after the 12‐week intervention program, pre‐ and post‐testing comprised of a static balance test, Star Excursion Balance Test (SEBT), Cooper’s test, sprint, the Step 50, vertical jump, and rebound jump were performed. After pre‐testing, players performed the SE or CE program three times per week for 12 weeks. A two‐way repeated‐measures ANOVA was used to assess the changes over time, and differences between the groups. Within‐group changes from pre‐testing to post‐testing were determined using paired t‐tests. Statistical significance was inferred from p < 0.05. Results: There were significant group‐by‐time interactions for posterolateral (p = 0.022) and posteromedial (p < 0.001) directions of the SEBT. Paired t‐tests revealed significant improvements of the posterolateral and posteromedial directions in the SE group. Although other measurements did not find group‐by‐time interactions, within‐group changes were detected indicating significant improvements in the static balance test, Cooper’s test, and rebound jump in the only SE group (p < 0.05). Vertical jump and sprint were improved significantly in both groups (p < 0.05), but the Step 50 was not improved in either group (p > 0.05). Conclusions: Results suggested that the SE has specific training effects that enhance static and dynamic balance, Cooper’s test, and rebound jump. Level of Evidence: 3b PMID:24567855

The acute phase response and exercise: court and field sports

PubMed Central

Fallon, K; Fallon, S; Boston, T

2001-01-01

Objective—To determine the presence or absence of an acute phase response after training for court and field sports. Participants—All members of the Australian women's soccer team (n = 18) and all members of the Australian Institute of Sport netball team (n = 14). Methods—Twelve acute phase reactants (white blood cell count, neutrophil count, platelet count, serum iron, ferritin, and transferrin, percentage transferrin saturation, α1 antitrypsin, caeruloplasmin, α2 acid glycoprotein, C reactive protein, and erythrocyte sedimentation rate) were measured during a rest period and after moderate and heavy training weeks in members of elite netball and women's soccer teams. Results—Responses consistent with an acute phase response were found in five of 24 tests in the soccer players, and in three of 24 tests in the netball players. Responses in the opposite direction were found in seven of 24 tests in the soccer players and two of 24 tests in the netballers. The most sensitive reactant measured, C reactive protein, did not respond in a manner typical of an acute phase response. Conclusion—An acute phase response does not seem to occur as a consequence of the levels of training typical of elite female netball and soccer teams. This has implications for the interpretation of biochemical variables in these groups. Key Words: acute phase response; iron; plasma proteins; inflammation PMID:11375875

The perceptions of professional soccer players on the risk of injury from competition and training on natural grass and 3rd generation artificial turf

PubMed Central

2014-01-01

Background The purpose of this study was to describe professional soccer players’ perceptions towards injuries, physical recovery and the effect of surface related factors on injury resulting from soccer participation on 3rd generation artificial turf (FT) compared to natural grass (NG). Methods Information was collected through a questionnaire that was completed by 99 professional soccer players from 6 teams competing in Major League Soccer (MLS) during the 2011 season. Results The majority (93% and 95%) of the players reported that playing surface type and quality influenced the risk of sustaining an injury. Players believed that playing and training on FT increased the risk of sustaining a non-contact injury as opposed to a contact injury. The players identified three surface related risk factors on FT, which they related to injuries and greater recovery times: 1) Greater surface stiffness 2) Greater surface friction 3) Larger metabolic cost to playing on artificial grounds. Overall, 94% of the players chose FT as the surface most likely to increase the risk of sustaining an injury. Conclusions Players believe that the risk of injury differs according to surface type, and that FT is associated with an increased risk of non-contact injury. Future studies should be designed prospectively to systematically track the perceptions of groups of professional players training and competing on FT and NG. PMID:24581229

Repeated-Sprint Sequences During Female Soccer Matches Using Fixed and Individual Speed Thresholds.

PubMed

Nakamura, Fábio Y; Pereira, Lucas A; Loturco, Irineu; Rosseti, Marcelo; Moura, Felipe A; Bradley, Paul S

2017-07-01

Nakamura, FY, Pereira, LA, Loturco, I, Rosseti, M, Moura, FA, and Bradley, PS. Repeated-sprint sequences during female soccer matches using fixed and individual speed thresholds. J Strength Cond Res 31(7): 1802-1810, 2017-The main objective of this study was to characterize the occurrence of single sprint and repeated-sprint sequences (RSS) during elite female soccer matches, using fixed (20 km·h) and individually based speed thresholds (>90% of the mean speed from a 20-m sprint test). Eleven elite female soccer players from the same team participated in the study. All players performed a 20-m linear sprint test, and were assessed in up to 10 official matches using Global Positioning System technology. Magnitude-based inferences were used to test for meaningful differences. Results revealed that irrespective of adopting fixed or individual speed thresholds, female players produced only a few RSS during matches (2.3 ± 2.4 sequences using the fixed threshold and 3.3 ± 3.0 sequences using the individually based threshold), with most sequences composing of just 2 sprints. Additionally, central defenders performed fewer sprints (10.2 ± 4.1) than other positions (fullbacks: 28.1 ± 5.5; midfielders: 21.9 ± 10.5; forwards: 31.9 ± 11.1; with the differences being likely to almost certainly associated with effect sizes ranging from 1.65 to 2.72), and sprinting ability declined in the second half. The data do not support the notion that RSS occurs frequently during soccer matches in female players, irrespective of using fixed or individual speed thresholds to define sprint occurrence. However, repeated-sprint ability development cannot be ruled out from soccer training programs because of its association with match-related performance.

Cognitive Functions in Elite and Sub-Elite Youth Soccer Players Aged 13 to 17 Years.

PubMed

Huijgen, Barbara C H; Leemhuis, Sander; Kok, Niels M; Verburgh, Lot; Oosterlaan, Jaap; Elferink-Gemser, Marije T; Visscher, Chris

2015-01-01

Soccer players are required to anticipate and react continuously in a changing, relatively unpredictable situation in the field. Cognitive functions might be important to be successful in soccer. The current study investigated the relationship between cognitive functions and performance level in elite and sub-elite youth soccer players aged 13-17 years. A total of 47 elite youth soccer players (mean age 15.5 years, SD = 0.9) and 41 sub-elite youth soccer players (mean age 15.2 years, SD = 1.2) performed tasks for "higher-level" cognitive functions measuring working memory (i.e., Visual Memory Span), inhibitory control (i.e., Stop-Signal Task), cognitive flexibility (i.e., Trail Making Test), and metacognition (i.e., Delis-Kaplan Executive Function System Design Fluency Test). "Lower-level" cognitive processes, i.e., reaction time and visuo-perceptual abilities, were also measured with the previous tasks. ANOVA's showed that elite players outscored sub-elite players at the "higher-level" cognitive tasks only, especially on metacognition (p < .05). Using stepwise discriminant analysis, 62.5% of subjects was correctly assigned to one of the groups based on their metacognition, inhibitory control and cognitive flexibility performance. Controlling for training hours and academic level, MANCOVA's showed differences in favor of the elite youth soccer players on inhibitory control (p = .001), and cognitive flexibility (p = .042), but not on metacognition (p = .27). No differences were found concerning working memory nor the "lower-level" cognitive processes (p > .05). In conclusion, elite youth soccer players have better inhibitory control, cognitive flexibility, and especially metacognition than their sub-elite counterparts. However, when training hours are taken into account, differences between elite and sub-elite youth soccer players remain apparent on inhibitory control and cognitive flexibility in contrast to metacognition. This highlights the need for longitudinal studies to further investigate the importance of "higher-level" cognitive functions for talent identification, talent development and performance in soccer.

Cognitive Functions in Elite and Sub-Elite Youth Soccer Players Aged 13 to 17 Years

PubMed Central

Huijgen, Barbara C. H.; Leemhuis, Sander; Kok, Niels M.; Verburgh, Lot; Oosterlaan, Jaap; Elferink-Gemser, Marije T.; Visscher, Chris

2015-01-01

Soccer players are required to anticipate and react continuously in a changing, relatively unpredictable situation in the field. Cognitive functions might be important to be successful in soccer. The current study investigated the relationship between cognitive functions and performance level in elite and sub-elite youth soccer players aged 13–17 years. A total of 47 elite youth soccer players (mean age 15.5 years, SD = 0.9) and 41 sub-elite youth soccer players (mean age 15.2 years, SD = 1.2) performed tasks for “higher-level” cognitive functions measuring working memory (i.e., Visual Memory Span), inhibitory control (i.e., Stop-Signal Task), cognitive flexibility (i.e., Trail Making Test), and metacognition (i.e., Delis-Kaplan Executive Function System Design Fluency Test). “Lower-level” cognitive processes, i.e., reaction time and visuo-perceptual abilities, were also measured with the previous tasks. ANOVA’s showed that elite players outscored sub-elite players at the “higher-level” cognitive tasks only, especially on metacognition (p < .05). Using stepwise discriminant analysis, 62.5% of subjects was correctly assigned to one of the groups based on their metacognition, inhibitory control and cognitive flexibility performance. Controlling for training hours and academic level, MANCOVA’s showed differences in favor of the elite youth soccer players on inhibitory control (p = .001), and cognitive flexibility (p = .042), but not on metacognition (p = .27). No differences were found concerning working memory nor the “lower-level” cognitive processes (p > .05). In conclusion, elite youth soccer players have better inhibitory control, cognitive flexibility, and especially metacognition than their sub-elite counterparts. However, when training hours are taken into account, differences between elite and sub-elite youth soccer players remain apparent on inhibitory control and cognitive flexibility in contrast to metacognition. This highlights the need for longitudinal studies to further investigate the importance of “higher-level” cognitive functions for talent identification, talent development and performance in soccer. PMID:26657073

Bridging the gap between empirical results, actual strategies, and developmental programs in soccer.

PubMed

Figueiredo, António J; Gonçalves, Carlos E; Tessitore, Antonio

2014-05-01

Being one of the most prominent globalized sports, soccer played at club, national, and continental levels has a relevant societal role. At present, the specific competencies, interests, and languages of the different actors involved in the selection, development, and support of long-lasting careers of players might limit opportunities for potential talented players. Unless the cultural environment of soccer resolves the gaps between empirical results and actual soccer strategies, scientific discussion relating to the effectiveness of talent selection and development remains limited. This commentary is intended to highlight the need for developmental programs to prepare soccer personnel for a transdisciplinary dialogue, which could foster a future development of this sport. Finally, in considering the wide soccer-related employment opportunities at local, national, and international levels, the need for a clear qualification framework is crucial.

Strength performance in youth: trainability of adolescents and children in the back and front squats.

PubMed

Keiner, Michael; Sander, Andre; Wirth, Klaus; Caruso, Oliver; Immesberger, Peter; Zawieja, Martin

2013-02-01

A basic question for many athletic coaches pertains to the maximum attainable strength level for youth athletes. The aim of this investigation was to establish reference values for the strength performance in the front and back squats in youth athletes. The strength performance in front and back squats of 141 elite youth soccer players was tested by a 1 repetition maximum (1RM) and 1RM related to bodyweight (SREL). The subjects aged between 11 and 19 years and were divided into 2 groups and 4 subgroups (A = younger than 19 years, B = younger than 17 years, C = younger than 15 years, and D = younger than 13 years). For approximately 2 years, one group (control group [CG]) only participated in routine soccer training and the other group (strength training group [STG]) participated in an additional strength training program along with the routine soccer training. Additionally, the strength performance in a 5RM in both squat variants of 105 young elite weightlifters (National Weightlifting Organization Baden Württemberg, [BWG]) was examined to show the high level of trainability of children and adolescents and to determine the reference strength values for young athletes. The STG performed in the parallel front squat SREL in the subgroups A 1.7 +/- 0.2, B 1.6 +/- 0.2, C 1.4 +/-0.2 and D 0.9 +/- 0.3. The STG had significantly (p < 0.001) higher strength values in 1RM and SREL than CG. The BWG had higher strength values than STG, but the BWG was not part of the statistical analysis because of the different test protocols (1RM vs. 5RM). Our data show that the SREL in parallel squat for young elite athletes with long-term training experience should be a minimum of 2.0 for 16- to 19-year-olds, 1.5 for 13- to 15-year-olds, and 0.7 for 11- to 12-year-olds.

Use of the RSA/RCOD Index to Identify Training Priority in Soccer Players.

PubMed

Wong, Del P; Hjelde, Geir H; Cheng, Ching-Feng; Ngo, Jake K

2015-10-01

The use of RSA/RCOD index indicates the repeated change-of-direction (RCOD) performance relative to the repeated-sprint ability (RSA) and provides a standardized approach to prioritize training needs for RSA and RCOD. To compare the RSA/RCOD index among different age groups, RSA and RCOD were measured from 20 under-16 players (U16), 20 under-19 players (U19), and 17 first-team professional players (PRO) from a football (soccer) club that has regular participation in the UEFA Champions League. Each player performed the RSA and RCOD tests, during which the fastest time (FT), average time (AT), total time (TT), and percentage decrement score (%Dec) were recorded. No significant differences were found in RSA/RCOD index-FT, AT, TT, and %Dec among the 3 groups (p > 0.05) and between U19 and PRO in all RSA and RCOD measures (p > 0.05). Most values of RSA/RCOD index were 0.51 among the U16, U19, and PRO groups. Moreover, we concluded that the RSA/RCOD index might not be further changed after 16 years of age unless specific training programs for RSA and RCOD are prescribed. Therefore, this study provides an empirical case, and coaches can establish the RSA/RCOD index value relevant to their training system and monitor players' training needs of RSA and RCOD in a longer term.

Nutritional profile of the Brazilian Amputee Soccer Team during the precompetition period for the world championship.

PubMed

Innocencio da Silva Gomes, Ainá; Gonçalves Ribeiro, Beatriz; de Abreu Soares, Eliane

2006-10-01

The purpose of this study was to determine the dietary and anthropometric profiles of the Brazilian amputee soccer players during the training period before the world soccer amputee championship, according to their positional roles in the game. Fifteen male athletes participated in the study. Data on height, weight, skinfold thickness, and circumferences were collected to assess nutritional status. Dietary intake was obtained by using 6-d dietary records, analyzed by a Nutrition Support Program for total energy intake, carbohydrates, proteins, lipids, vitamins, and minerals. One-way analysis of variance was used to identify differences in groups (P < 0.05). Midfield players were heavier than the others, and this difference may have been caused by a large quantity of subcutaneous fat. Dietary data showed a low carbohydrate intake and high protein and fat intakes. No athlete met the recommendations for vitamin E, and forward players did not meet recommendations for calcium. Amputee athletes need an individualized nutritional orientation and the lack of information about disabled sports and athletes highlights the need for more studies in this area.

Within Session Sequence of Balance and Plyometric Exercises Does Not Affect Training Adaptations with Youth Soccer Athletes.

PubMed

Chaouachi, Mehdi; Granacher, Urs; Makhlouf, Issam; Hammami, Raouf; Behm, David G; Chaouachi, Anis

2017-03-01

The integration of balance and plyometric training has been shown to provide significant improvements in sprint, jump, agility, and other performance measures in young athletes. It is not known if a specific within session balance and plyometric exercise sequence provides more effective training adaptations. The objective of the present study was to investigate the effects of using a sequence of alternating pairs of exercises versus a block (series) of all balance exercises followed by a block of plyometric exercises on components of physical fitness such as muscle strength, power, speed, agility, and balance. Twenty-six male adolescent soccer players (13.9 ± 0.3 years) participated in an 8-week training program that either alternated individual balance (e.g., exercises on unstable surfaces) and plyometric (e.g., jumps, hops, rebounds) exercises or performed a block of balance exercises prior to a block of plyometric exercises within each training session. Pre- and post-training measures included proxies of strength, power, agility, sprint, and balance such as countermovement jumps, isometric back and knee extension strength, standing long jump, 10 and 30-m sprints, agility, standing stork, and Y-balance tests. Both groups exhibited significant, generally large magnitude (effect sizes) training improvements for all measures with mean performance increases of approximately >30%. There were no significant differences between the training groups over time. The results demonstrate the effectiveness of combining balance and plyometric exercises within a training session on components of physical fitness with young adolescents. The improved performance outcomes were not significantly influenced by the within session exercise sequence.

Postural control in 13-year-old soccer players

PubMed Central

Bieć, Ewa

2010-01-01

To evaluate the effect of early systematic soccer training on postural control we measured center-of-pressure (COP) variability, range, mean velocity and frequency in bipedal quiet stance with eyes open (EO) and closed (EC) in 44 boys aged 13 (25 boys who practiced soccer for 5–6 years and 19 healthy boys who did not practice sports). The soccer players had better stability, particularly in the medial–lateral plane (M/L); their COP variability and range were lower than in controls in both EO (p < 0.05) and EC (p < 0.0005) condition indicating that the athletes were less dependent on vision than non-athletes. Improved stability of athletes was accompanied by a decrease in COP frequency (p < 0.001 in EO, and p < 0.04 in EC) which accounted for lower regulatory activity of balance system in soccer players. The athletes had lower COP mean velocity than controls (p < 0.0001 in both visual condition), with larger difference in the M/L than A/P plane (p < 0.00001 and p < 0.05, respectively). Postural behavior was more variable within the non-athletes than soccer players, mainly in the EC stances (p < 0.005 for all COP parameters). We conclude that: (1) soccer training described was efficient in improving the M/L postural control in young boys; (2) athletes developed specific postural strategies characterized by decreased COP frequency and lower reliance on vision. PMID:20582432

Effect of Vertical, Horizontal, and Combined Plyometric Training on Explosive, Balance, and Endurance Performance of Young Soccer Players.

PubMed

Ramírez-Campillo, Rodrigo; Gallardo, Francisco; Henriquez-Olguín, Carlos; Meylan, Cesar M P; Martínez, Cristian; Álvarez, Cristian; Caniuqueo, Alexis; Cadore, Eduardo L; Izquierdo, Mikel

2015-07-01

The aim of this study was to compare the effects of 6 weeks of vertical, horizontal, or combined vertical and horizontal plyometric training on muscle explosive, endurance, and balance performance. Forty young soccer players aged between 10 and 14 years were randomly divided into control (CG; n = 10), vertical plyometric group (VG; n = 10), horizontal plyometric group (HG; n = 10), and combined vertical and horizontal plyometric group (VHG; n = 10). Players performance in the vertical and horizontal countermovement jump with arms, 5 multiple bounds test (MB5), 20-cm drop jump reactive strength index (RSI20), maximal kicking velocity (MKV), sprint, change of direction speed (CODS), Yo-Yo intermittent recovery level 1 test (Yo-Yo IR1), and balance was measured. No significant or meaningful changes in the CG, apart from small change in the Yo-Yo IR1, were observed while all training programs resulted in meaningful changes in explosive, endurance, and balance performance. However, only VHG showed a statistically significant (p ≤ 0.05) increase in all performance test and most meaningful training effect difference with the CG across tests. Although no significant differences in performance changes were observed between experimental groups, the VHG program was more effective compared with VG (i.e., jumps, MKV, sprint, CODS, and balance performance) and HG (i.e., sprint, CODS, and balance performance) to small effect. The study demonstrated that vertical, horizontal, and combined vertical and horizontal jumps induced meaningful improvement in explosive actions, balance, and intermittent endurance capacity. However, combining vertical and horizontal drills seems more advantageous to induce greater performance improvements.

Effects of the Workplace Health Promotion Activities Soccer and Zumba on Muscle Pain, Work Ability and Perceived Physical Exertion among Female Hospital Employees.

PubMed

Barene, Svein; Krustrup, Peter; Holtermann, Andreas

2014-01-01

This 40-week workplace physical training RCT investigated the effect of soccer and Zumba, respectively, on muscle pain intensity and duration, work ability, and rating of perceived exertion (RPE) during work among female hospital employees. 107 hospital employees were cluster-randomized into two training groups, and a control group. The training was conducted outside working hours as two-three 1-h sessions per week for the first 12 weeks, and continued as one-two 1-h sessions per week for the last 28 weeks. Muscle pain intensity and duration, work ability, and RPE during work were measured at baseline and after 12 and 40 weeks. After 12 weeks, both the soccer (-1.9, 95% CI, -3.0, -0.8, P = 0.001) and the Zumba group (-1.3, 95% CI, -2.3, -0.3, P = 0.01) reduced the pain intensity (on a scale from 0 to 10) in the neck-shoulder region (eta squared = 0.109), whereas only the soccer group (-1.9, 95% CI, -3.2, -0.7, P = 0.002, eta squared = 0.092) showed a reduction after 40 weeks referencing the control group. After 40 weeks, both the soccer (-16.4 days, 95% CI, -29.6, -3.2, P<0.02) and the Zumba group (-16.6 days, 95% CI, -28.9, -4.2, P<0.01) reduced the pain duration during the past 3 months in the neck-shoulder region (eta squared = 0.077). No significant effects on intensity or duration of pain in the lower back, RPE during work or work ability were found. The present study indicates that workplace initiated soccer and Zumba training improve neck-shoulder pain intensity as well as duration among female hospital employees. International Standard Randomized Controlled Trial Number Register ISRCTN 61986892.

Effects of the Workplace Health Promotion Activities Soccer and Zumba on Muscle Pain, Work Ability and Perceived Physical Exertion among Female Hospital Employees

PubMed Central

Barene, Svein; Krustrup, Peter; Holtermann, Andreas

2014-01-01

Objectives This 40-week workplace physical training RCT investigated the effect of soccer and Zumba, respectively, on muscle pain intensity and duration, work ability, and rating of perceived exertion (RPE) during work among female hospital employees. Methods 107 hospital employees were cluster-randomized into two training groups, and a control group. The training was conducted outside working hours as two-three 1-h sessions per week for the first 12 weeks, and continued as one-two 1-h sessions per week for the last 28 weeks. Muscle pain intensity and duration, work ability, and RPE during work were measured at baseline and after 12 and 40 weeks. Results After 12 weeks, both the soccer (−1.9, 95% CI, −3.0, −0.8, P = 0.001) and the Zumba group (−1.3, 95% CI, −2.3, −0.3, P = 0.01) reduced the pain intensity (on a scale from 0 to 10) in the neck-shoulder region (eta squared = 0.109), whereas only the soccer group (−1.9, 95% CI, −3.2, −0.7, P = 0.002, eta squared = 0.092) showed a reduction after 40 weeks referencing the control group. After 40 weeks, both the soccer (-16.4 days, 95% CI, −29.6, −3.2, P<0.02) and the Zumba group (-16.6 days, 95% CI, −28.9, −4.2, P<0.01) reduced the pain duration during the past 3 months in the neck-shoulder region (eta squared = 0.077). No significant effects on intensity or duration of pain in the lower back, RPE during work or work ability were found. Conclusions The present study indicates that workplace initiated soccer and Zumba training improve neck-shoulder pain intensity as well as duration among female hospital employees. Trial Registration International Standard Randomized Controlled Trial Number Register ISRCTN 61986892. PMID:25494175

Health-Related Physical Fitness in Healthy Untrained Men: Effects on VO2max, Jump Performance and Flexibility of Soccer and Moderate-Intensity Continuous Running.

PubMed

Milanović, Zoran; Pantelić, Saša; Sporiš, Goran; Mohr, Magni; Krustrup, Peter

2015-01-01

The purpose of this study was to determine the effects of recreational soccer (SOC) compared to moderate-intensity continuous running (RUN) on all health-related physical fitness components in healthy untrained men. Sixty-nine participants were recruited and randomly assigned to one of three groups, of which sixty-four completed the study: a soccer training group (SOC; n = 20, 34±4 (means±SD) years, 78.1±8.3 kg, 179±4 cm); a running group (RUN; n = 21, 32±4 years, 78.0±5.5 kg, 179±7 cm); or a passive control group (CON; n = 23, 30±3 years, 76.6±12.0 kg, 178±8 cm). The training intervention lasted 12 weeks and consisted of three 60-min sessions per week. All participants were tested for each of the following physical fitness components: maximal aerobic power, minute ventilation, maximal heart rate, squat jump (SJ), countermovement jump with arm swing (CMJ), sit-and-reach flexibility, and body composition. Over the 12 weeks, VO2max relative to body weight increased more (p<0.05) in SOC (24.2%, ES = 1.20) and RUN (21.5%, ES = 1.17) than in CON (-5.0%, ES = -0.24), partly due to large changes in body mass (-5.9, -5.7 and +2.6 kg, p<0.05 for SOC, RUN and CON, respectively). Over the 12 weeks, SJ and CMJ performance increased more (p<0.05) in SOC (14.8 and 12.1%, ES = 1.08 and 0.81) than in RUN (3.3 and 3.0%, ES = 0.23 and 0.19) and CON (0.3 and 0.2%), while flexibility also increased more (p<0.05) in SOC (94%, ES = 0.97) than in RUN and CON (0-2%). In conclusion, untrained men displayed marked improvements in maximal aerobic power after 12 weeks of soccer training and moderate-intensity running, partly due to large decreases in body mass. Additionally soccer training induced pronounced positive effects on jump performance and flexibility, making soccer an effective broad-spectrum fitness training intervention.

Muscle Contraction Velocity: A Suitable Approach to Analyze the Functional Adaptations in Elite Soccer Players

PubMed Central

Loturco, Irineu; Pereira, Lucas A.; Kobal, Ronaldo; Kitamura, Katia; Ramírez-Campillo, Rodrigo; Zanetti, Vinicius; Abad, Cesar C. Cal; Nakamura, Fabio Y.

2016-01-01

Tensiomyography (TMG) has been used as a simple and non-invasive tool to assess the mechanical properties of skeletal muscles. The TMG-derived velocity of contraction (Vc), which can be calculated from the ratio between maximal radial displacement and the sum of contraction time and delay time, has been proposed for evaluating athletes. However, its sensitivity to training effects and possible relation with changes in soccer players’ neuromuscular performance have not yet been addressed. To test this possibility, twenty-two male Brazilian elite soccer players were assessed using TMG-derived Vc, unloaded squat jump, countermovement jump and drop jump at 45 cm, loaded jump squat and linear (20 m) and change of direction (COD) sprint tests, prior to and after an 8-week period, between two consecutive official tournaments, during which the concurrency between endurance and strength-power training commonly impairs neuromuscular capacities. Magnitude-based inference was used to detect meaningful training effects. From pre- to post-tests, it was observed likely to almost certainly improvements in all modes of jumping tests. In addition, we could verify decrements in the 20-m and COD sprint performances, which were rated as very likely and almost certainly, respectively. Finally, both rectus femoris and biceps femoris muscles presented a likely reduction in Vc. Therefore, chronic decreases in sprinting speed are possibly accompanied by a reduced TMG-derived Vc. From a practical standpoint, the TMG-derived Vc can be used to monitor negative specific-soccer training effects related to potential impairments in maximum speed. Key points Tensiomyography (TMG) can be considered a useful technology for coaches and sport scientists seeking for non-invasive and practical tools to assess the muscle function of elite athletes; Velocity of contraction (Vc) is a single index able to integrate several of the reliable mechanical outcomes provided by TMG, which was shown to be sensitive to detect neuromuscular impairments in professional soccer players; After 8 weeks of specific soccer training, the changes in the Vc seem to occur in the same direction as the reductions in maximal sprint ability and COD speed. PMID:27803627

Relationships between rating-of-perceived-exertion- and heart-rate-derived internal training load in professional soccer players: a comparison of on-field integrated training sessions.

PubMed

Campos-Vazquez, Miguel Angel; Mendez-Villanueva, Alberto; Gonzalez-Jurado, Jose Antonio; León-Prados, Juan Antonio; Santalla, Alfredo; Suarez-Arrones, Luis

2015-07-01

To describe the internal training load (ITL) of common training sessions performed during a typical week and to determine the relationships between different indicators of ITL commonly employed in professional football (soccer). Session-rating-of-perceived-exertion TL (sRPE-TL) and heart-rate- (HR) derived measurements of ITL as Edwards TL and Stagno training impulses (TRIMPMOD) were used in 9 players during 3 periods of the season. The relationships between them were analyzed in different training sessions during a typical week: skill drills/circuit training + small-sided games (SCT+SSGs), ball-possession games+technical-tactical exercises (BPG+TTE), tactical training (TT), and prematch activation (PMa). HR values obtained during SCT+SSGs and BPG+TTE were substantially greater than those in the other 2 sessions, all the ITL markers and session duration were substantially greater in SCT+SSGs than in any other session, and all ITL measures in BPG+TTE were substantially greater than in TT and PMa sessions. Large relationships were found between HR>80% HRmax and HR>90% HRmax vs sRPE-TL during BPG+TTE and TT sessions (r=.61-.68). Very large relationships were found between Edwards TL and sRPE-TL and between TRIMPMOD and sRPE-TL in sessions with BPG+TTE and TT (r=.73-.87). Correlations between the different HR-based methods were always extremely large (r=.92-.98), and unclear correlations were observed for other relationships between variables. sRPE-TL provided variable-magnitude within-individual correlations with HR-derived measures of training intensity and load during different types of training sessions typically performed during a week in professional soccer. Caution should be applied when using RPE- or HR-derived measures of exercise intensity/load in soccer training interchangeably.

Neuroplus biofeedback improves attention, resilience, and injury prevention in elite soccer players.

PubMed

Rusciano, Aiace; Corradini, Giuliano; Stoianov, Ivilin

2017-06-01

Performance and injury prevention in elite soccer players are typically investigated from physical-tactical, biomechanical, and metabolic perspectives. However, executive functions, visuospatial abilities, and psychophysiological adaptability or resilience are also fundamental for efficiency and well-being in sports. Based on previous research associating autonomic flexibility with prefrontal cortical control, we designed a novel integrated autonomic biofeedback training method called Neuroplus to improve resilience, visual attention, and injury prevention. Herein, we introduce the method and provide an evaluation of 20 elite soccer players from the Italian Soccer High Division (Serie-A): 10 players trained with Neuroplus and 10 trained with a control treatment. The assessments included psychophysiological stress profiles, a visual search task, and indexes of injury prevention, which were measured pre- and posttreatment. The analysis showed a significant enhancement of physiological adaptability, recovery following stress, visual selective attention, and injury prevention that were specific to the Neuroplus group. Enhancing the interplay between autonomic and cognitive functions through biofeedback may become a key principle for obtaining excellence and well-being in sports. To our knowledge, this is the first evidence that shows improvement in visual selective attention following intense autonomic biofeedback. © 2017 Society for Psychophysiological Research.

Between-game variation of physical soccer performance measures in highly trained youth soccer players.

PubMed

Doncaster, Greg; Unnithan, Viswanath

2017-07-12

To assess the between-game variation in measures of physical performance during 11 v 11 soccer match-play, over a short period of time, in highly trained youth soccer players. A single cohort observational study design was employed. Physical match performance data were collected from 17 male, highly trained youth soccer players (age: 13.3 ± 0.4 y) over three, 2 x 20min, 11 v 11 matches. Using 10 Hz GPS, the variables selected for analyses were total distance (TD), high-speed running (HSR), very high-speed running (VHSR), number of high-speed running efforts (HSReff) and number of very high-speed running efforts (VHSReff). Match data was also separated into cumulative 5 min epochs, to identify the peak 5 min epoch and the mean of the cumulative 5 min epochs for each match. Variability was quantified using the coefficient of variation (CV), Standard error of measurement (SEM) and intra-class correlation coefficient (ICC). Between- and within-player smallest worthwhile changes (SWC) were also calculated for each variable to aid in the interpretation of the data. Analysis of the variance between games reported a low CV for TD (3.8%) but larger CVs for HSR (33.3%), HSReff (35.4%) and VHSR and VHSReff (59.6 and 57.4 %, respectively). Analysis of 5 min epochs (peak and average) found an increase in the CVs beyond that of the values reported for the whole match. Between-player SWC in high intensity physical performance data ranged from 24.7 - 42.4 %, whereas within-player SWC ranged from 1.2 - 79.9%. The between-game variability of high and very high intensity activities in youth soccer players, across three soccer matches over a short period of time (2 weeks), is relatively 'large' and specific to the individual, thus highlighting the need for caution when interpreting physical performance data between games and players.

Iron, Hematological Parameters and Blood Plasma Lipid Profile in Vitamin D Supplemented and Non-Supplemented Young Soccer Players Subjected to High-Intensity Interval Training.

PubMed

Jastrzebska, Maria; Kaczmarczyk, Mariusz; Suárez, Arturo Diaz; Sánchez, Guillermo Felipe López; Jastrzebska, Joanna; Radziminski, Lukasz; Jastrzebski, Zbigniew

2017-01-01

Vitamin D deficiency has been associated with increased risk for cardiovascular disease and anemia. Vitamin D-related changes in lipid profile have been studied extensively but the relationship between vitamin D and lipid metabolism is not completely understood. As both vitamin D and intermittent training may potentially affect iron and lipid metabolism, the aim of the study was to evaluate whether a daily supplementation of vitamin D can modulate the response of hematological and lipid parameters to high-intensity interval training (HIIT) in soccer players. Thirty-six young elite junior soccer players were included in the placebo-controlled, double-blind study. Participants were non-randomly allocated into either a supplemented group (SG, n=20, HIIT and 5,000 IU of vitamin D daily) or placebo group (PG, n=16, HIIT and sunflower oil). Hematological parameters were ascertained before and after the 8-wk training. The change score (post- and pre-training difference) was calculated for each individual and the mean change score (MCS) was compared between SG and PG using the t test and analysis of covariance. There were no differences between SG and PG at baseline. The red and white cell count, hemoglobin, hematocrit, MCHC, ferritin, and HDL-cholesterol changed significantly over the 8-wk HIIT. However, no significant differences in MCS were observed between SG and PG for any variable. A daily vitamin D supplement did not have any impact on alteration in hematological or lipid parameters in young soccer players in the course of high-intensity interval training.

Prematch salivary secretory immunoglobulin a in soccer players from the 2014 World Cup qualifying campaign.

PubMed

Morgans, Ryland; Owen, Adam; Doran, Dominic; Drust, Barry; Morton, James P

2015-04-01

To monitor resting salivary secretory immunoglobulin A (SIgA) levels in international soccer players during the short-term training period that precedes international match play. In a repeated-measure design, saliva samples were obtained from 13 outfield soccer players who participated in the training camps preceding 7 games (5 home and 2 away) of the 2014 FIFA World Cup qualifying campaign. Samples were obtained daily for 4 d preceding each game (and analyzed for SIgA using the IPRO oral-fluid-collection system) at match day minus 1 (MD-1), minus 2 (MD-2), minus 3 (MD-3), and minus 4 (MD-4). SIgA displayed a progressive decline (P = .01) during the 4-d training period (MD-4, 365 ± 127 μg/mL; MD-3, 348 ± 154 μg/mL; MD-2, 290 ± 138 μg/mL; MD-1, 256 ± 90 μg/mL) such that MD-1 values were significantly lower (P = .01) than both MD-4 and MD-3. The 95% confidence intervals for the differences between MD-1 and MD-4 were -191 to -26 and between MD-1 and MD-3 were -155 to -28. Data demonstrate that a short-term soccer-training camp in preparation for international competition induces detectable perturbations to mucosal immunity. Future studies should monitor SIgA (as a practical and noninvasive measure of immunity) alongside internal and external measures of training load in an attempt to strategically individualize training and nutritional strategies that may support optimal preparation for high-level competition.

The hydration status of young female elite soccer players during an official tournament.

PubMed

Chapelle, Laurent; Tassignon, Bruno; Aerenhouts, Dirk; Mullie, Patrick; Clarys, Peter

2017-09-01

The hydration status of elite female soccer players is a concern, especially during high-volume training periods or tournaments. Furthermore, scientific literature on this topic is scarce to non-existent. Therefore, the primary aim of this study was to evaluate the hydration status in elite youth female soccer players during an official tournament. The secondary aim was to identify a possible relationship between pre-training hydration status and fluid intake. Eighteen players were followed during eight consecutive days. Urine specific gravity was used to assess hydration status. Body weight was monitored before and after every training and match, whilst individual fluid intake was only registered during training. The players were informed about their hydration status on day 5. On days 1 to 4, the percentage of players who were at least minimally hypohydrated ranged between 44% and 78%. On day 5 (rest day), all the players were at least minimally hypohydrated. After the information session on day 5, the relative number of euhydrated players increased to 89% on both day 6 (training day) and day 7 (match day). On the final day (rest day), all players were either minimally hypohydrated or hypohydrated. Furthermore, a moderate and significant negative correlation (r=-0.44; N.=54; P=0.01) was found between fluid intake during and USG value before the training sessions. The data illustrates that the hydration status of this population of elite youth female soccer players may be suboptimal and is of substantial concern on rest days during this tournament under temperate conditions. Receiving personal advice about rehydration seems to have a positive effect.

Reliability and Construct Validity of Yo-Yo Tests in Untrained and Soccer-Trained Schoolgirls Aged 9-16.

PubMed

Póvoas, Susana C; Castagna, Carlo; da Costa Soares, José Manuel; Silva, Pedro; Coelho-E-Silva, Manuel João; Matos, Fernando; Krustrup, Peter

2016-05-01

The reliability and construct validity of three age-adapted-intensity Yo-Yo tests were evaluated in untrained (n = 67) vs. soccer-trained (n = 65) 9- to 16-year-old schoolgirls. Tests were performed 7 days apart for reliability (9- to 11-year-old: Yo-Yo intermittent recovery level 1 children's test; 12- to 13-yearold: Yo-Yo intermittent endurance level 1; and 14- to 16-year-old: Yo-Yo intermittent endurance level 2). Yo-Yo distance covered was 40% (776 ± 324 vs. 556 ± 156 m), 85% (1252 ± 484 vs. 675 ± 252 m) and 138% (674 ± 336 vs. 283 ± 66 m) greater (p ≤ .010) for the soccer-trained than for the untrained girls aged 9-11, 12-13 and 14-16 years, respectively. Typical errors of measurement for Yo-Yo distance covered, expressed as a percentage of the coefficient of variation (confidence limits), were 10.1% (8.1-13.7%), 11.0% (8.6-15.4%) and 11.6% (9.2-16.1%) for soccer players, and 11.5% (9.1-15.8%), 14.1% (11.0-19.8%) and 10.6% (8.5-14.2%) for untrained girls, aged 9-11, 12-13 and 14-16, respectively. Intraclass correlation coefficient values for test-retest were excellent (0.795-0.973) in both groups. No significant differences were observed in relative exercise peak heart rate (%HRpeak) between groups during test and retest. The Yo-Yo tests are reliable for determining intermittent-exercise capacity and %HRpeak for soccer players and untrained 9- to 16-year-old girls. They also possess construct validity with better performances for soccer players compared with untrained age-matched girls, despite similar %HRpeak.

Maturity-associated variation in change of direction and dribbling speed in early pubertal years and 5-year developmental changes in young soccer players.

PubMed

Valente-Dos-Santos, J; Coelho-E-Silva, M J; Vaz, V; Figueiredo, A J; Capranica, L; Sherar, L B; Elferink-Gemser, M T; Malina, R M

2014-06-01

The purpose of the current study was to assess the developmental changes in change of direction and dribbling speed in youth soccer players taking into account skeletal age (SA), maturity status, body size, estimated fat mass, aerobic endurance, lower limb explosive strength and annual volume of training. Eighty-three male soccer players aged 10-15 years (SA) at baseline were annually followed over 5 years, resulting in an average 4.4 observations per player. After testing for multicollinearity, multi-level regression modeling was used to examine the longitudinal developmental changes on change of direction and dribbling speed. Maturity-associated variability was significant in change of direction and also dribbling speed among young soccer players aged 12-14 years with better scores being performed by late maturers. Moreover, the predicted longitudinal scores for change of direction and dribbling speed improved with SA (P<0.01), SA2 (P<0.01) and skeletal maturity status entered as an additional developmental predictor (P<0.05). Estimated fat-free mass (P<0.01), aerobic endurance (P<0.01) and lower limb strength (P<0.01) were additional predictors in both models. The soccer-specific skill, dibbling speed, was also explained by annual volume of training (P<0.05). Skeletal maturity status explains inter-individual variability on maximal short-term run performances with and without the ball possession at early ages of participation in competitive soccer. The effects tend to persist across ages combined with longitudinal changes in body composition and functional fitness. In the particular case of the ball test, annual volume of training was also a longitudinal performance predictor.

Soccer Injury Movement Screen (SIMS) Composite Score Is Not Associated With Injury Among Semi-Professional Soccer Players.

PubMed

McCunn, Robert; Fünten, Karen Aus der; Whalan, Matthew; Sampson, John A; Meyer, Tim

2018-05-08

Study Design Prospective cohort. Background The association between movement quality and injury is equivocal. No soccer-specific movement assessment has been prospectively investigated in relation to injury risk. Objectives To investigate the association between a soccer-specific movement quality assessment and injury risk among semi-professional soccer players. Methods Semi-professional soccer players (n=306) from 12 clubs completed the Soccer Injury Movement Screen (SIMS) during the pre-season period. Individual training/match exposure and non-contact time loss injuries were recorded prospectively for the entirety of the 2016 season. Relative risks (RR) were calculated, and presented with 90% confidence intervals (CI), for the SIMS composite and individual sub-test scores from generalized linear models with Poisson distribution offset for exposure. Results When considering non-contact time loss lower extremity injuries (primary level of analysis), there was a most likely trivial association with the SIMS composite score. Similarly, SIMS composite score demonstrated most likely to likely trivial associations to all injury categories included in the secondary level of analysis (non-contact time loss hip/groin, thigh, knee and ankle injuries). When considering hamstring strains and ankle sprains specifically (tertiary level of analysis) the SIMS composite score, again, demonstrated very likely trivial associations. A total of 262 non-contact time loss injuries were recorded. The overall (training and match exposure combined) incidence of non-contact time loss injury was 12/1000 hours. Conclusion The SIMS composite score demonstrated no association to any of the investigated categories of soccer-related injury. The SIMS composite score should not be used to group players into 'high' or 'low' risk groups. Level of Evidence Prognosis, level 4. J Orthop Sports Phys Ther, Epub 8 May 2018. doi:10.2519/jospt.2018.8037.

Effectiveness of an injury prevention programme for adult male amateur soccer players: a cluster-randomised controlled trial

PubMed Central

van Beijsterveldt, Anna M C; van de Port, Ingrid G L; Krist, Mark R; Schmikli, Sandor L; Stubbe, Janine H; Frederiks, Janet E; Backx, Frank J G

2012-01-01

Background The incidence rate of soccer injuries is among the highest in sports, particularly for adult male soccer players. Purpose To investigate the effect of the ‘The11’ injury prevention programme on injury incidence and injury severity in adult male amateur soccer players. Study design Cluster-randomised controlled trial. Methods Teams from two high-level amateur soccer competitions were randomly assigned to an intervention (n=11 teams, 223 players) or control group (n=12 teams, 233 players). The intervention group was instructed to perform The11 in each practice session during one soccer season. The11 focuses on core stability, eccentric training of thigh muscles, proprioceptive training, dynamic stabilisation and plyometrics with straight leg alignment. All participants of the control group continued their practice sessions as usual. Results In total, 427 injuries were recorded, affecting 274 of 456 players (60.1%). Compliance with the intervention programme was good (team compliance=73%, player compliance=71%). Contrary to the hypothesis, injury incidences were almost equal between the two study groups: 9.6 per 1000 sports hours (8.4–11.0) for the intervention group and 9.7 (8.5–11.1) for the control group. No significant differences were found in injury severity, but a significant difference was observed in the location of the injuries: players in the intervention group sustained significantly less knee injuries. Conclusions This study did not find significant differences in the overall injury incidence or injury severity between the intervention and control group of adult male soccer players. More research is recommended, focusing on injury aetiology and risk factors in adult male amateur soccer players. PMID:22878257

Groin pain and soccer players: male versus female occurrence.

PubMed

Karlsson, M K; Dahan, R; Magnusson, H; Nyquist, F; Rosengren, B E

2014-08-01

Groin pain is common in soccer players. Comparison of results from different studies, especially between genders, is difficult as studies use different definitions and data collection procedures. Therefore we conducted a study of both male and female soccer players enabling direct gender comparison. The study enrolled 479 male soccer players aged 25 years (17-43) (mean with range) and 144 female soccer players aged 23 years (16-47), who answered a mailed questionnaire that included specific questions on groin pain and sports history. Data are presented as proportions (%) or as mean with 95% confidence intervals (95% CI). Groin pain was experienced by 55% of male soccer players and 28% of female soccer players, resulting in an odds ratio (OR) of 2.9 (95% CI 1.9, 4.5). Groin pain occurred more often in the preseason, than during the rest of the season in both male and female players (both P<0.001). Playing position in the team or playing league did not seem to influence the risk of suffering groin pain. In soccer players, male gender and preseasonal training appear to be risk factors for developing groin pain.

Is strength-training frequency a key factor to develop performance adaptations in young elite soccer players?

PubMed

Otero-Esquina, Carlos; de Hoyo Lora, Moisés; Gonzalo-Skok, Óliver; Domínguez-Cobo, Sergio; Sánchez, Hugo

2017-11-01

The aim of this study was to analyse the effects of a combined strength-training programme (full-back squat, YoYo TM leg curl, plyometrics and sled towing exercises) on performance in elite young soccer players and to examine the effects when this training programme was performed one or two days per week. Thirty-six male soccer players (U-17 to U-19) were recruited and assigned to experimental groups (EXP1: 1 s w -1 ; EXP2: 2 s w -1 ) or a control group (CON). Performance was assessed through a countermovement jump (CMJ) test (relative peak power [CMJ PP ] and CMJ height [CMJ H ]), a 20-m linear sprint test with split-times at 10-m, and a change of direction test (V-cut test) 1 week before starting the training programme and also 1 week after performing such training programme. Within-group analysis showed substantial improvements in CMJ variables (ES: 0.39-0.81) and COD (ES: 0.70 and 0.76) in EXP1 and EXP2, while EXP2 also showed substantial enhancements in all linear sprinting tests (ES: 0.43-0.52). Between-group analysis showed substantially greater improvements in CMJ variables (ES: 0.39-0.68) in experimental groups in comparison to CON. Furthermore, EXP2 achieved a substantial better performance in 20-m (ES: 0.48-0.64) than EXP1 and CON. Finally, EXP2 also showed greater enhancements in 10-m (ES: 0.50) and V-cut test (ES: 0.52) than EXP1. In conclusion, the combined strength-training programme improved jumping ability, independently of training frequency, though the achievement of two sessions per week also enhanced sprinting abilities (linear and COD) in young soccer players.

Nutritional aspects of women's soccer.

PubMed

Brewer, J

1994-01-01

Female soccer players often have only limited time available to prepare and consume meals, due to the constraints faced by having to combine training and playing with full-time occupations. The energy expenditure of females playing soccer has been estimated at approximately 70% VO2 max, corresponding to an energy production of around 4600 kJ (1100 kcal). As with male soccer players, carbohydrate consumption is essential to support the demands of playing, training and to facilitate recovery. There are some reports to suggest that females in team sports may consume diets with a low energy intake, due to the desire to lose or maintain body weight. In extreme cases, this can result in eating disorders. However, there is no clear evidence to suggest that this problem is common among female soccer players. To maintain a consistent balance between energy intake and expenditure, players should receive nutritional advice to cover all phases of the year, not just the competitive season. Dietary calcium and iron supplements may be a useful precautionary measure, in players who are known to be at risk of deficiencies in these areas. Correct and sensitive nutritional counselling is essential for players and coaches.

Quantification of training load during one-, two- and three-game week schedules in professional soccer players from the English Premier League: implications for carbohydrate periodisation.

PubMed

Anderson, Liam; Orme, Patrick; Di Michele, Rocco; Close, Graeme L; Morgans, Ryland; Drust, Barry; Morton, James P

2016-01-01

Muscle glycogen is the predominant energy source for soccer match play, though its importance for soccer training (where lower loads are observed) is not well known. In an attempt to better inform carbohydrate (CHO) guidelines, we quantified training load in English Premier League soccer players (n = 12) during a one-, two- and three-game week schedule (weekly training frequency was four, four and two, respectively). In a one-game week, training load was progressively reduced (P < 0.05) in 3 days prior to match day (total distance = 5223 ± 406, 3097 ± 149 and 2912 ± 192 m for day 1, 2 and 3, respectively). Whilst daily training load and periodisation was similar in the one- and two-game weeks, total accumulative distance (inclusive of both match and training load) was higher in a two-game week (32.5 ± 4.1 km) versus one-game week (25.9 ± 2 km). In contrast, daily training total distance was lower in the three-game week (2422 ± 251 m) versus the one- and two-game weeks, though accumulative weekly distance was highest in this week (35.5 ± 2.4 km) and more time (P < 0.05) was spent in speed zones >14.4 km · h(-1) (14%, 18% and 23% in the one-, two- and three-game weeks, respectively). Considering that high CHO availability improves physical match performance but high CHO availability attenuates molecular pathways regulating training adaptation (especially considering the low daily customary loads reported here, e.g., 3-5 km per day), we suggest daily CHO intake should be periodised according to weekly training and match schedules.

Prevalence of Dehydration Before Training Sessions, Friendly and Official Matches in Elite Female Soccer Players

PubMed Central

Castro-Sepulveda, Mauricio; Astudillo, Javier; Letelier, Pablo

2016-01-01

Abstract This study aimed to evaluate and compare the hydration states prior to different sporting events (training sessions, friendly and official matches) in elite female soccer players and relate that to the importance that the player attached to the hydration state as a determinant of sports performance. The hydration state of 17 female elite soccer players (age: 21.5 ± 3 years; body mass: 62 ± 6 kg; body height: 165 ± 9 cm) was determined by measuring their urine specific gravity (USG) prior to three different sports events: training sessions (PT), friendly (PF) and official (PO) matches. The importance that each player attached to the hydration state as a determinant of sports performance was evaluated through a simple questionnaire. An average of 47.05% of the soccer players were severely dehydrated (USG > 1.030), 33.33% were significantly dehydrated (USG > 1.020), 17.64% were mildly dehydrated (USG > 1.010) and 1.96% were euhydrated (USG < 1.010). The average USG was 1.027 ± 0.007 (PT = 1.029 ± 0.009; PF = 1.023 ± 0.010 and PO = 1.030 ± 0.006). Differences were found between urine specific gravity prior to a friendly and an official match (p = 0.03). No relationship was found between urine specific gravity and the importance each player attached to the hydration state as a determinant of sports performance. The results show that dehydration is the most prevalent hydration state of elite soccer players before training sessions, friendly and official matches. Players were most dehydrated prior to official matches, which was unlinked to the players’ perceived importance of hydration for sports performance. PMID:28149344

Half-squat or jump squat training under optimum power load conditions to counteract power and speed decrements in Brazilian elite soccer players during the preseason.

PubMed

Loturco, Irineu; Pereira, Lucas A; Kobal, Ronaldo; Zanetti, Vinicius; Gil, Saulo; Kitamura, Katia; Abad, Cesar Cavinato Cal; Nakamura, Fabio Y

2015-01-01

The purpose of this study was to test which specific type of exercise (i.e., jump squat (JS) or half-squat (HS)) is more effective at maintaining speed and power abilities throughout a preseason in soccer players. Twenty-three male soccer players were randomly allocated into two groups: JS and HS. The mean propulsive power, vertical jumping ability, and sprinting performance were evaluated before and after 4 weeks of a preseason period. The optimum power loads for the JS and HS exercises were assessed and were used as load-references. The soccer players performed 10 power oriented training sessions in total. Both JS and HS maintained power in JS and speed abilities (P > 0.05, for main effects and interaction effect) as indicated by ANCOVA. Both groups demonstrated reduced power during HS (ES = -0.76 vs. -0.78, for JS and HS, respectively); both groups improved acceleration (ACC) from 5 to 10 m (ES = 0.52). JS was more effective at reducing the ACC decrements over 0-5 m (ES = -0.38 vs. -0.58, for JS and HS, respectively). The HS group increased squat jump height (ES = 0.76 vs. 0.11, for HS and JS, respectively). In summary, JS is more effective in reducing the ACC capacity over very short sprints while HS is more effective in improving squat jump performance. Both strategies improve ACC over longer distances. New training strategies should be implemented/developed to avoid concurrent training effects between power and endurance adaptations during professional soccer preseasons.

Body composition and physical performance during a National Collegiate Athletic Association Division I men's soccer season.

PubMed

Silvestre, Ricardo; Kraemer, William J; West, Chris; Judelson, Daniel A; Spiering, Barry A; Vingren, Jakob L; Hatfield, Disa L; Anderson, Jeffrey M; Maresh, Carl M

2006-11-01

The purpose of this study was to examine changes in body composition (BC) and physical performance tests (PT) resulting from a competitive season in soccer. Twenty-five male collegiate players (age = 19.9 +/- 1.3 years; height = 177.6 +/- 6.4 cm; body mass = 77.6 +/- 8.6 kg, and percentage body fat = 12.8 +/- 5.2%) were tested before (PRE) and after (POST) the 2003-2004 National Collegiate Athletic Association season. The following tests were performed: BC (anthropometric and dual energy x-ray absorptiometry measurements), vertical jump (VJ), 9.1-m (9 m) and 36.5-m (36 m) sprint, lower-body power (LP), total body power (TP), and cardiorespiratory endurance (VO(2)max). Training was divided into soccer-specific training: field warm-up drills, practices, games, and additional conditioning sessions. A daily, unplanned, nonlinear periodization model was used to assign session volume and intensity for strength sessions (total repetitions < or =96 and workload was > or =80% of 1 repetition maximum). For the entire team, body mass significantly increased by 1.5 +/- 0.4 kg from PRE to POST due to a significant increase in total lean tissue (0.9 +/- 0.2 kg). Regionally, lean tissue mass significantly increased in the legs (0.4 +/- 0.0 kg) and trunk (0.3 +/- 0.1 kg). Physical performance variables were very similar for the entire team at PRE and POST; VJ (cm) = 61.9 +/- 7.1 PRE vs. 63.3 +/- 8.0 POST, 9.1-m (s) = 1.7 +/- 0.1 PRE and POST, 36.5-m (s) = 5.0 +/- 0.2 PRE and POST, predicted VO(2)max (ml.kg.min(-1))= 59.8 +/- 3.3 PRE vs. 60.9 +/- 3.4 POST. The only significant improvements across the season were for TP (17.3%) and for LP (10.7%). In conclusion, soccer athletes who begin a season with a high level of fitness can maintain, and in some cases improve, body composition and physical performance from before to after a competitive season. A correct combination of soccer-specific practices and strength and conditioning programs can maintain and develop physical performance, allowing a soccer athlete to perform optimally throughout pre-, in-, and postseason play.

Biomechanical Effects of an Injury Prevention Program in Preadolescent Female Soccer Athletes

PubMed Central

Thompson, Julie A.; Tran, Andrew A.; Gatewood, Corey T.; Shultz, Rebecca; Silder, Amy; Delp, Scott L.; Dragoo, Jason L.

2017-01-01

Background Anterior cruciate ligament (ACL) injuries are common, and children as young as 10 years of age exhibit movement patterns associated with an ACL injury risk. Prevention programs have been shown to reduce injury rates, but the mechanisms behind these programs are largely unknown. Few studies have investigated biomechanical changes after injury prevention programs in children. Purpose/Hypothesis To investigate the effects of the F-MARC 11+ injury prevention warm-up program on changes to biomechanical risk factors for an ACL injury in preadolescent female soccer players. We hypothesized that the primary ACL injury risk factor of peak knee valgus moment would improve after training. In addition, we explored other kinematic and kinetic variables associated with ACL injuries. Study Design Controlled laboratory study. Methods A total of 51 female athletes aged 10 to 12 years were recruited from soccer clubs and were placed into an intervention group (n = 28; mean [±SD] age, 11.8 ± 0.8 years) and a control group (n = 23; mean age, 11.2 ± 0.6 years). The intervention group participated in 15 in-season sessions of the F-MARC 11+ program (2 times/wk). Pre- and postseason motion capture data were collected during preplanned cutting, unanticipated cutting, double-leg jump, and single-leg jump tasks. Lower extremity joint angles and moments were estimated using OpenSim, a biomechanical modeling system. Results Athletes in the intervention group reduced their peak knee valgus moment compared with the control group during the double-leg jump (mean [±standard error of the mean] pre- to posttest change, −0.57 ± 0.27 %BW×HT vs 0.25 ± 0.25 %BW×HT, respectively; P = .034). No significant differences in the change in peak knee valgus moment were found between the groups for any other activity; however, the intervention group displayed a significant pre- to posttest increase in peak knee valgus moment during unanticipated cutting (P = .044). Additional analyses revealed an improvement in peak ankle eversion moment after training during preplanned cutting (P = .015), unanticipated cutting (P = .004), and the double-leg jump (P = .016) compared with the control group. Other secondary risk factors did not significantly improve after training, although the peak knee valgus angle improved in the control group compared with the intervention group during unanticipated cutting (P = .018). Conclusion The F-MARC 11+ program may be effective in improving some risk factors for an ACL injury during a double-leg jump in preadolescent athletes, most notably by reducing peak knee valgus moment. Clinical Relevance This study provides motivation for enhancing injury prevention programs to produce improvement in other ACL risk factors, particularly during cutting and single-leg tasks. PMID:27793803

Biomechanical Effects of an Injury Prevention Program in Preadolescent Female Soccer Athletes.

PubMed

Thompson, Julie A; Tran, Andrew A; Gatewood, Corey T; Shultz, Rebecca; Silder, Amy; Delp, Scott L; Dragoo, Jason L

2017-02-01

Anterior cruciate ligament (ACL) injuries are common, and children as young as 10 years of age exhibit movement patterns associated with an ACL injury risk. Prevention programs have been shown to reduce injury rates, but the mechanisms behind these programs are largely unknown. Few studies have investigated biomechanical changes after injury prevention programs in children. Purpose/Hypothesis: To investigate the effects of the F-MARC 11+ injury prevention warm-up program on changes to biomechanical risk factors for an ACL injury in preadolescent female soccer players. We hypothesized that the primary ACL injury risk factor of peak knee valgus moment would improve after training. In addition, we explored other kinematic and kinetic variables associated with ACL injuries. Controlled laboratory study. A total of 51 female athletes aged 10 to 12 years were recruited from soccer clubs and were placed into an intervention group (n = 28; mean [±SD] age, 11.8 ± 0.8 years) and a control group (n = 23; mean age, 11.2 ± 0.6 years). The intervention group participated in 15 in-season sessions of the F-MARC 11+ program (2 times/wk). Pre- and postseason motion capture data were collected during preplanned cutting, unanticipated cutting, double-leg jump, and single-leg jump tasks. Lower extremity joint angles and moments were estimated using OpenSim, a biomechanical modeling system. Athletes in the intervention group reduced their peak knee valgus moment compared with the control group during the double-leg jump (mean [±standard error of the mean] pre- to posttest change, -0.57 ± 0.27 %BW×HT vs 0.25 ± 0.25 %BW×HT, respectively; P = .034). No significant differences in the change in peak knee valgus moment were found between the groups for any other activity; however, the intervention group displayed a significant pre- to posttest increase in peak knee valgus moment during unanticipated cutting ( P = .044). Additional analyses revealed an improvement in peak ankle eversion moment after training during preplanned cutting ( P = .015), unanticipated cutting ( P = .004), and the double-leg jump ( P = .016) compared with the control group. Other secondary risk factors did not significantly improve after training, although the peak knee valgus angle improved in the control group compared with the intervention group during unanticipated cutting ( P = .018). The F-MARC 11+ program may be effective in improving some risk factors for an ACL injury during a double-leg jump in preadolescent athletes, most notably by reducing peak knee valgus moment. This study provides motivation for enhancing injury prevention programs to produce improvement in other ACL risk factors, particularly during cutting and single-leg tasks.

Heart rate monitoring in soccer: interest and limits during competitive match play and training, practical application.

PubMed

Alexandre, Dellal; da Silva, Cristiano Diniz; Hill-Haas, Stephen; Wong, Del P; Natali, Antonio J; De Lima, Jorge R P; Bara Filho, Mauricio G B; Marins, Joao J C B; Garcia, Emerson Silami; Karim, Chamari

2012-10-01

The identification of physiological loads imposed by soccer training or match play reveals essential information, which may help improve training and recovery strategies. Until today, the use of heart rate (HR) monitoring is not standardized in soccer. Thus, the aim of this review was to analyze, determine and compare the exercise intensity (EI) monitored by HR in professional, youth, and recreational soccer players during matches and training sessions using a meta-analysis. Heart rate is one of the most common physiological variables used to determine exercise internal training load. The mean EI recorded during competitive matches was described as 70-80% of VO2max or 80-90% of maximal heart rate (HRmax), independent of the playing level. With respect to HR training zones, approximately 65% of the total match duration is spent at intensity of 70-90% HRmax and rarely below 65% HRmax. However, although HRmax is mostly employed in the literature, monitoring EI should be expressed in relation to reserve heart rate, as it was described as a more reliable indicator of HR, allowing interindividual comparisons. The HR response according to the playing position indicates that midfielders are characterized by the highest EI, followed by forwards and fullbacks. Moreover, in the second half of the match, the EI is lower than that observed during the first half; this reduction could be correlated with the level of the player's physical conditioning. Consequently, coaches may favor the use of interval training or small-sided training games because these are shown to improve both aerobic capacity and the ability to repeat high-intensity actions. Small-sided games allow reaching similar HR responses to those found during interval training and match play but with greater heterogeneity values. Future investigations should include a larger sample of players with special reference to playing position and the expression of EI in percentage of the reserve heart rate, analyzing the possible intergender differences in HR response.

Adaptations to Speed Endurance Training in Highly Trained Soccer Players.

PubMed

Nyberg, Michael; Fiorenza, Matteo; Lund, Anders; Christensen, Magnus; Rømer, Tue; Piil, Peter; Hostrup, Morten; Christensen, Peter M; Holbek, Simon; Ravnholt, Thomas; Gunnarsson, Thomas P; Bangsbo, Jens

2016-07-01

The present study examined whether a period of additional speed endurance training would improve intense intermittent exercise performance in highly trained soccer players during the season and whether the training changed aerobic metabolism and the level of oxidative enzymes in type I and type II muscle fibers. During the last 9 wk of the season, 13 semiprofessional soccer players performed additional speed endurance training sessions consisting of two to three sets of 8-10 repetitions of 30-m sprints with 10 s of passive recovery (SET). Before and after SET, subjects completed a double-step exercise protocol that included transitions from standing to moderate-intensity running (~75% HRmax), followed by transitions from moderate- to high-intensity running (~90% HRmax) in which pulmonary oxygen uptake (V˙O2) was determined. In addition, the yo-yo intermittent recovery test level 1 was performed, and a muscle biopsy was obtained at rest. The yo-yo intermittent recovery test level 1 performance was 11.6% ± 6.4% (mean ± SD) better (2803 ± 330 vs 3127 ± 383 m, P < 0.05) after SET compared with before SET. In the transition from standing to moderate-intensity running, phase II pulmonary V˙O2 kinetics was 11.4% ± 16.5% faster (P < 0.05), and the running economy at this intensity was 2.3% ± 3.0% better (P < 0.05). These improvements were apparent despite the content of muscle proteins regulating oxidative metabolism (3-hydroxyacyl CoA dehydrogenase, COX IV, and OXPHOS), and capillarization was reduced (P < 0.05). The content of 3-hydroxyacyl CoA dehydrogenase and citrate synthase in type I and type II fibers did not change. In highly trained soccer players, additional speed endurance training is associated with an improved ability to perform repeated high-intensity work. To what extent the training-induced changes in V˙O2 kinetics and mechanical efficiency in type I fibers caused the improvement in performance warrants further investigation.

Guiding attention aids the acquisition of anticipatory skill in novice soccer goalkeepers.

PubMed

Ryu, Donghyun; Kim, Seonjin; Abernethy, Bruce; Mann, David L

2013-06-01

The ability to anticipate the actions of opponents can be enhanced through perceptual-skill training, though there is doubt regarding the most effective form of doing so. We sought to evaluate whether perceptual-skill learning would be enhanced when supplemented with guiding visual information. Twenty-eight participants without soccer-playing experience were assigned to a guided perceptual-training group (n = 9), an unguided perceptual-training group (n = 10), or a control group (n = 9). The guided perceptual-training group received half of their trials with color cueing that highlighted either the key kinematic changes in the kicker's action or the known visual search strategy of expert goalkeepers. The unguided perceptual-training group undertook an equal number of trials of practice, but all trials were without guidance. The control group undertook no training intervention. All participants completed an anticipation test immediately before and after the 7-day training intervention, as well as a 24-hr retention test. The guided perceptual-training group significantly improved their response accuracy for anticipating the direction of soccer penalty kicks from preintervention to postintervention, whereas no change in performance was evident at posttest for either the unguided perceptual-training group or the control group. The superior performance of the guided perceptual-training group was preserved in the retention test and was confirmed when relative changes in response time were controlled using a covariate analysis. Perceptual training supplemented with guiding information provides a level of improvement in perceptual anticipatory skill that is not seen without guidance.

Hydration status and fluid intake of urban, underprivileged South African male adolescent soccer players during training.

PubMed

Gordon, Reno Eron; Kassier, Susanna Maria; Biggs, Chara

2015-01-01

Poor hydration compromises performance and heightens the risk of heat stress which adolescents are particularly susceptible to as they produce comparatively larger amount of metabolic heat during exercise. This study determined the hydration status and fluid intake of socio-economically disadvantaged, male adolescent soccer players during training. A pilot study was conducted among 79 soccer players (mean age 15.9 ± 0.8 years; mean BMI 20.2 ± 2.1 kg/m(2)). Hydration status was determined before and after two training sessions, using both urine specific gravity and percent loss of body weight. The type and amount of fluid consumed was assessed during training. A self-administered questionnaire was used to determine the players' knowledge regarding fluid and carbohydrate requirements for soccer training. Players were at risk of developing heat illness during six of the 14 training sessions (60 - 90 minutes in length). Although on average players were slightly dehydrated (1.023 ± 0.006 g/ml) before and after (1.024 ± 0.007 g/ml) training, some were extremely dehydrated before (24%) and after (27%) training. Conversely some were extremely hyperhydrated before (3%) and after training (6%). The mean percent loss of body weight was 0.7 ± 0.7%. The majority did not consume fluid during the first (57.0%) and second (70.9%) training sessions. An average of 216.0 ± 140.0 ml of fluid was consumed during both training sessions. The majority (41.8%) consumed water, while a few (5.1%) consumed pure fruit juice. More than 90% stated that water was the most appropriate fluid to consume before, during and after training. Very few (5.0%) correctly stated that carbohydrate should be consumed before, during and after training. Approximately a quarter were severely dehydrated. Many did not drink or drank insufficient amounts. The players' beliefs regarding the importance of fluid and carbohydrate consumption did not correspond with their practices. A nutrition education programme is needed to educate players on the importance of fluid and carbohydrate to prevent dehydration and ensure appropriate carbohydrate intake.

Periodization and physical performance in elite female soccer players.

PubMed

Mara, Jocelyn K; Thompson, Kevin G; Pumpa, Kate L; Ball, Nick B

2015-07-01

To investigate the variation in training demands, physical performance, and player well-being across a women's soccer season. Seventeen elite female players wore GPS tracking devices during every training session (N=90) throughout 1 national-league season. Intermittent high-speed-running capacity and 5-, 15-, and 25-m-sprint testing were conducted at the beginning of preseason, end of preseason, midseason, and end of season. In addition, subjective well-being measures were self-reported daily by players over the course of the season. Time over 5 m was lowest at the end of preseason (mean 1.148 s, SE 0.017 s) but then progressively deteriorated to the end of the season (P<.001). Sprint performance over 15 m improved by 2.8% (P=.013) after preseason training, while 25-m-sprint performance peaked at midseason, with a 3.1% (P=.05) improvement from the start of preseason, before declining at the end of season (P=.023). Training demands varied between phases, with total distance and high-speed distance greatest during preseason before decreasing (P<.001) during the early- and late-season phases. Endurance capacity and well-being measures did not change across training phases. Monitoring training demands and subsequent physical performance in elite female soccer players allow coaches to ensure that training periodization goals are being met and related positive training adaptations are being elicited.

Energy and carbohydrate for training and recovery.

PubMed

Burke, Louise M; Loucks, Anne B; Broad, Nick

2006-07-01

Soccer players should achieve an energy intake that provides sufficient carbohydrate to fuel the training and competition programme, supplies all nutrient requirements, and allows manipulation of energy or nutrient balance to achieve changes in lean body mass, body fat or growth. Although the traditional culture of soccer has focused on carbohydrate intake for immediate match preparation, top players should adapt their carbohydrate intake on a daily basis to ensure adequate fuel for training and recovery between matches. For players with a mobile playing style, there is sound evidence that dietary programmes that restore and even super-compensate muscle glycogen levels can enhance activity patterns during matches. This will presumably also benefit intensive training, such as twice daily practices. As well as achieving a total intake of carbohydrate commensurate with fuel needs, the everyday diet should promote strategic intake of carbohydrate and protein before and after key training sessions to optimize the adaptations and enhance recovery. The achievement of the ideal physique for soccer is a long-term goal that should be undertaken over successive years, and particularly during the off-season and pre-season. An increase in lean body mass or a decrease in body fat is the product of a targeted training and eating programme. Consultation with a sports nutrition expert can assist soccer players to manipulate energy and nutrient intake to meet such goals. Players should be warned against the accidental or deliberate mismatch of energy intake and energy expenditure, such that energy availability (intake minus the cost of exercise) falls below 125 kJ (30 kcal) per kilogram of fat-free mass per day. Such low energy availability causes disturbances to hormonal, metabolic, and immune function.

Resistance training status and effectiveness of low frequency resistance training on upper-body strength and power in highly trained soccer players.

PubMed

Hertzog, Maxime; Rumpf, Michael Clemens; Hader, Karim

2017-08-26

Soccer is classified as a contact/collision sport with many player-to-player duels. Winning these duels, shielding the ball or fending off an opponent requires upper-body strength and power. Therefore this study aimed, a) to examine the time-related effect of an upper-body RT on maximal strength and power changes in highly trained soccer players, b) to investigate if the resistance-training (RT) status influences these changes throughout a competitive season. Twenty-eight soccer players participated in this study and were divided into an untrained (UG) and a trained (TG) group, according to their RT status. Both groups performed the same upper-body RT once a week, over 30 weeks. Maximal strength (1RM) and maximal power (MP) were assessed before, during and after the competitive season. Both groups significantly improved 1RM and MP over the entire competitive season, with a moderate (TG, 13%) to very large (UG, 21%) magnitude in 1RM and with a small (TG, 8%) to moderate (UG, 13%) magnitude in MP. After the initial 10 weeks of RT, UG presented significant and slightly (1RM) to moderately (MP) greater improvements than TG. For all other time intervals, the between-groups changes in 1RM were rated as similar. For the last 20 weeks of the RT, the change in MP was significantly lower for UG compared to TG. One upper-body RT-session per week will provide sufficient stimulus to enable an almost certain improvement in strength and power throughout a competitive season for all players disregarding their initial RT status.

Exercise to rest ratios in RSA training in women's soccer.

PubMed

Ruscello, Bruno; Esposito, Mario; Partipilo, Filippo; DI Cicco, Dalila; Filetti, Cristoforo; Pantanella, Laura; D'Ottavio, Stefano

2017-10-27

To investigate the applicability of three different exercise to rest ratios in RSA training in women's soccer players, applying those ones already adopted in male adult and young players, when performing three different sprinting modes (straight, shuttle and sprinting with changing of direction). 15 trained female soccer players (height: 1.65 ± 0.06 m; weight: 59.3 ± 9.0 kg; BMI 21.6 ± 2.7 kg·m-2; age: 23.3±5.9 years) participated to the study. In order to compare the different values of the time recorded, an Index of Fatigue was used. Recovery times among trials in the sets were administered according to the 1:5, 1:3; 1:2 exercise to rest ratio, respectively. Blood lactate concentrations at the end of each set (3') were analyzed. Significant differences among trials within each set (Repeated Measures Anova; p<0.05) were found, as evidence of fatigue over time, with an average decay of performance of about 5% but no significant differences were found in IF%, among the three different sprinting modalities when applying the investigated exercise to rest ratios (Factorial Anova; between; p>0.05). Significant differences were found in blood lactate concentrations (p<0.05). The results of this study confirm that the exercise to rest ratios considered in this study might be suitable to design effective testing protocols and training sessions aimed at the development of the RSA in women's soccer players, keeping the performances in the speed domain (IF% < ⊕7-8%) but inducing the fatigue processes sought with this kind of training method.

Soccer: Special Olympics Sports Skills Instructional Program.

ERIC Educational Resources Information Center

Joseph P. Kennedy, Jr. Foundation, Washington, DC.

One of five guides in the Sports Skills Instructional Program of the Special Olympics, the booklet describes an approach to teaching soccer skills to mentally retarded persons. An introductory section lists the goals, objectives, and benefits of the program and provides criterion referenced instruments to assess the individual's current…

Eccentric rehabilitation exercise increases peritendinous type I collagen synthesis in humans with Achilles tendinosis.

PubMed

Langberg, H; Ellingsgaard, H; Madsen, T; Jansson, J; Magnusson, S P; Aagaard, P; Kjaer, M

2007-02-01

It has been shown that 12 weeks of eccentric heavy resistance training can reduce pain in runners suffering from chronic Achilles tendinosis, but the mechanism behind the effectiveness of this treatment is unknown. The present study investigates the local effect of an eccentric training regime on elite soccer players suffering from chronic Achilles tendinosis on the turnover of the peritendinous connective tissue. Twelve elite male soccer players, of whom six suffered from unilateral tendinosis and six were healthy controls, participated in this study. All participants performed 12 weeks of heavy-resistance eccentric training apart from their regular training and soccer activity. Before and after the training period the tissue concentration of indicators of collagen turnover was measured by the use of the microdialysis technique. After training, collagen synthesis was increased in the initially injured tendon (n=6; carboxyterminal propeptide of type I collagen (PICP): pre 3.9+/-2.5 microg/L to post 19.7+/-5.4 microg/L, P<0.05). The collagen synthesis was unchanged in healthy tendons in response to training (n=6; PICP: pre 8.3+/-5.2 microg/L to post 11.5+/-5.0 microg/L, P>0.05). Collagen degradation, measured as carboxyterminal telopeptide region of type I collagen (ICTP), was not affected by training neither in the injured nor in the healthy tendons. The clinical effect of the 12 weeks of eccentric training was determined by using a standardized loading procedure of the Achilles tendons showing a decrease in pain in all the chronic injured tendons (VAS before 44+/-9, after 13+/-9; P<0.05), and all subjects were back playing soccer following the eccentric training regime. The present study demonstrates that chronically injured Achilles tendons respond to 12 weeks of eccentric training by increasing collagen synthesis rate. In contrast, the collagen metabolism in healthy control tendons seems not to be affected by eccentric training. These findings could indicate a relation between collagen metabolism and recovery from injury in human tendons.

Impact of Ramadan on physical performance in professional soccer players

PubMed Central

Zerguini, Yacine; Kirkendall, Donald; Junge, Astrid; Dvorak, Jiri

2007-01-01

Objective Ramadan is a period of daylight abstention from liquid or solid nutrients. As sports continue to be scheduled, an understanding of the effects of Ramadan on Muslim athletes is warranted. Design Two Algerian professional soccer teams (55 men) were studied. Field tests of physical and soccer performance were collected before, at the end and 2 weeks after Ramadan in 2004. Players were queried on sleeping habits and personal perception of training and match performance. Setting Field setting at club training ground. Main outcome measures Performance on fitness and skill tests. Results Performance declined significantly (p<0.05) for speed, agility, dribbling speed and endurance, and most stayed low after the conclusion of Ramadan. Nearly 70% of the players thought that their training and performance were adversely affected during the fast. Conclusions The phase shift of food intake and disruption of sleep patterns affect actual and perceived physical performance. Islamic athletes need to explore strategies that will maximise performance during Ramadan. PMID:17224435

CHANGES IN THE ANAEROBIC THRESHOLD IN AN ANNUAL CYCLE OF SPORT TRAINING OF YOUNG SOCCER PLAYERS

PubMed Central

Andrzejewski, M.; Wieczorek, A.; Barinow-Wojewódzki, A.; Jadczak, Ł.; Adrian, S.; Pietrzak, M.; Wieczorek, S.

2013-01-01

The aim of the study was to assess changes in the anaerobic threshold of young soccer players in an annual training cycle. A group of highly trained 15-18 year old players of KKS Lech Poznań were tested. The tests included an annual training macrocycle, and its individual stages resulted from the time structure of the sports training. In order to assess the level of exercise capacities of the players, a field exercise test of increasing intensity was carried out on a soccer pitch. The test made it possible to determine the 4 millimolar lactate threshold (T LA 4 mmol · l-1) on the basis of the lactate concentration in blood [LA], to establish the threshold running speed and the threshold heart rate [HR]. The threshold running speed at the level of the 4 millimolar lactate threshold was established using the two-point form of the equation of a straight line. The obtained indicators of the threshold running speed allowed for precise establishment of effort intensity used in individual training in developing aerobic endurance. In order to test the significance of differences in mean values between four dates of tests, a non-parametric Friedman ANOVA test was used. The significance of differences between consecutive dates of tests was determined using a post-hoc Friedman ANOVA test. The tests showed significant differences in values of selected indicators determined at the anaerobic threshold in various stages of an annual training cycle of young soccer players. The most beneficial changes in terms of the threshold running speed were noted on the fourth date of tests, when the participants had the highest values of 4.01 m · s-1 for older juniors, and 3.80 m · s-1 for younger juniors. This may be indicative of effective application of an individualized programme of training loads and of good preparation of teams for competition in terms of players’ aerobic endurance. PMID:24744480

Changes in the anaerobic threshold in an annual cycle of sport training of young soccer players.

PubMed

Sliwowski, R; Andrzejewski, M; Wieczorek, A; Barinow-Wojewódzki, A; Jadczak, L; Adrian, S; Pietrzak, M; Wieczorek, S

2013-06-01

The aim of the study was to assess changes in the anaerobic threshold of young soccer players in an annual training cycle. A group of highly trained 15-18 year old players of KKS Lech Poznań were tested. The tests included an annual training macrocycle, and its individual stages resulted from the time structure of the sports training. In order to assess the level of exercise capacities of the players, a field exercise test of increasing intensity was carried out on a soccer pitch. The test made it possible to determine the 4 millimolar lactate threshold (T LA 4 mmol · l(-1)) on the basis of the lactate concentration in blood [LA], to establish the threshold running speed and the threshold heart rate [HR]. The threshold running speed at the level of the 4 millimolar lactate threshold was established using the two-point form of the equation of a straight line. The obtained indicators of the threshold running speed allowed for precise establishment of effort intensity used in individual training in developing aerobic endurance. In order to test the significance of differences in mean values between four dates of tests, a non-parametric Friedman ANOVA test was used. The significance of differences between consecutive dates of tests was determined using a post-hoc Friedman ANOVA test. The tests showed significant differences in values of selected indicators determined at the anaerobic threshold in various stages of an annual training cycle of young soccer players. The most beneficial changes in terms of the threshold running speed were noted on the fourth date of tests, when the participants had the highest values of 4.01 m · s(-1) for older juniors, and 3.80 m · s(-1) for younger juniors. This may be indicative of effective application of an individualized programme of training loads and of good preparation of teams for competition in terms of players' aerobic endurance.

Talent identification and development in soccer.

PubMed

Williams, A M; Reilly, T

2000-09-01

In this review, we attempt to integrate the main research findings concerned with talent identification and development in soccer. Research approaches in anthropometry, physiology, psychology and sociology are considered and, where possible, integrated. Although some progress has been made in identifying correlates of playing success, it appears that no unique characteristics can be isolated with confidence. Both biological and behavioural scientists have indicated a strong genetic component in performance of sports such as soccer; nevertheless, the influence of systematic training and development programmes should not be underestimated. We conclude that the sport and exercise sciences have an important support role in the processes of identifying, monitoring and nurturing talented soccer players towards realizing their potential.

An audit of injuries in six english professional soccer academies.

PubMed

Read, Paul J; Oliver, Jon L; De Ste Croix, Mark B A; Myer, Gregory D; Lloyd, Rhodri S

2018-07-01

Regulations now state that professional academies in the United Kingdom are required to substantially increase the volume of soccer training. This study assessed the current injury occurrence, providing an update to reports published prior to the introduction of the Elite Player Performance Plan (EPPP). 608 soccer players aged 11-18 years from six professional soccer clubs were prospectively monitored, recording injuries during the 2014-2015 season. An injury rate of 1.32 injuries per player/season was indicated with a mean time loss of 21.9 days per injury. The greatest time loss per injury was in the U14s-U15s, and the highest rate of severe injuries in the U15s. Strains and sprains were the most common injury type, with the knee and ankle the most frequently injured anatomical sites. Seasonal variation indicated two peaks in injury incidence, occurring in September and January. In comparison to a published audit prior to the inception of the EPPP, this study indicates that academy soccer players are three-times more likely to experience an injury. Given that time loss and injury severity also increased during periods that typically follow rapid growth, these players should be considered an important group for training load monitoring and injury prevention strategies.

Monitoring stress and recovery: new insights for the prevention of injuries and illnesses in elite youth soccer players.

PubMed

Brink, Michel S; Visscher, Chris; Arends, Suzanne; Zwerver, Johannes; Post, Wendy J; Lemmink, Koen Apm

2010-09-01

Elite youth soccer players have a relatively high risk for injuries and illnesses due to increased physical and psychosocial stress. The aim of this study is to investigate how measures to monitor stress and recovery, and its analysis, provide useful information for the prevention of injuries and illnesses in elite youth soccer players. 53 elite soccer players between 15 and 18 years of age participated in this study. To determine physical stress, soccer players registered training and match duration and session rating of perceived exertion for two competitive seasons by means of daily training logs. The Dutch version of the Recovery Stress Questionnaire for athletes (RESTQ-Sport) was administered monthly to assess the psychosocial stress-recovery state of players. The medical staff collected injury and illness data using the standardised Fédération Internationale de Football Association registration system. ORs and 95% CIs were calculated for injuries and illnesses using multinomial regression analyses. The independent measures were stress and recovery. During the study period, 320 injuries and 82 illnesses occurred. Multinomial regression demonstrated that physical stress was related to both injury and illness (range OR 1.01 to 2.59). Psychosocial stress and recovery were related the occurrence of illness (range OR 0.56 to 2.27). Injuries are related to physical stress. Physical stress and psychosocial stress and recovery are important in relation to illness. Individual monitoring of stress and recovery may provide useful information to prevent soccer players from injuries and illnesses.

Sports injuries profile of a first division Brazilian soccer team: a descriptive cohort study.

PubMed

Reis, Guilherme F; Santos, Thiago R T; Lasmar, Rodrigo C P; Oliveira Júnior, Otaviano; Lopes, Rômulo F F; Fonseca, Sérgio T

2015-01-01

To establish the injury profile of soccer players from a first division Brazilian soccer team. In addition, we investigated the association between the characteristics of the injuries and the player's age and position. Forty-eight players from a Brazilian first division soccer team were followed during one season. Descriptive statistics were used to characterize the injury profile. Spearman's tests were used to verify the association between the number and severity of injuries and the player's age. Chi-square test was used to verify the association between type of injury and player's position. Fisher's exact test was used to verify the association between the severity of injuries and player's position. The incidence of injuries was 42.84/1000 hours in matches and 2.40/1000 hours in training. The injury severity was 19.5±34.4 days off competition or training. Lower limb was the most common location of injury and most injuries were muscular/tendinous, overuse, non-recurrent, and non-contact injuries. Player's age correlated with the amount and severity of muscle and tendon injuries. Defenders had more minimal injuries (1-3 days lost), while forwards had more moderate (8-28 days lost) and severe injuries (>28 days lost). Furthermore, wingbacks had more muscle and tendon injuries, while midfielders had more joint and ligament injuries. The injury profile of the Brazilian players investigated in this study reflected regional differences in soccer practices. Results confirm the influence of the player's age and position on the soccer injuries profile.

Comparison of Static and Dynamic Balance in Female Collegiate Soccer, Basketball, and Gymnastics Athletes

PubMed Central

Bressel, Eadric; Yonker, Joshua C; Kras, John; Heath, Edward M

2007-01-01

Context: How athletes from different sports perform on balance tests is not well understood. When prescribing balance exercises to athletes in different sports, it may be important to recognize performance variations. Objective: To compare static and dynamic balance among collegiate athletes competing or training in soccer, basketball, and gymnastics. Design: A quasi-experimental, between-groups design. Independent variables included limb (dominant and nondominant) and sport played. Setting: A university athletic training facility. Patients or Other Participants: Thirty-four female volunteers who competed in National Collegiate Athletic Association Division I soccer (n = 11), basketball (n = 11), or gymnastics (n = 12). Intervention(s): To assess static balance, participants performed 3 stance variations (double leg, single leg, and tandem leg) on 2 surfaces (stiff and compliant). For assessment of dynamic balance, participants performed multidirectional maximal single-leg reaches from a unilateral base of support. Main Outcome Measure(s): Errors from the Balance Error Scoring System and normalized leg reach distances from the Star Excursion Balance Test were used to assess static and dynamic balance, respectively. Results: Balance Error Scoring System error scores for the gymnastics group were 55% lower than for the basketball group (P = .01), and Star Excursion Balance Test scores were 7% higher in the soccer group than the basketball group (P = .04). Conclusions: Gymnasts and soccer players did not differ in terms of static and dynamic balance. In contrast, basketball players displayed inferior static balance compared with gymnasts and inferior dynamic balance compared with soccer players. PMID:17597942

The Energy Cost of Running with the Ball in Soccer.

PubMed

Piras, Alessandro; Raffi, Milena; Atmatzidis, Charalampos; Merni, Franco; Di Michele, Rocco

2017-11-01

Running with the ball is a soccer-specific activity frequently used by players during match play and training drills. Nevertheless, the energy cost (EC) of on-grass running with the ball has not yet been determined. The purpose of this study was therefore to assess the EC of constant-speed running with the ball, and to compare it with the EC of normal running. Eight amateur soccer players performed two 6- min runs at 10 km/h on artificial turf, respectively with and without the ball. EC was measured with indirect calorimetry and, furthermore, estimated with a method based on players' accelerations measured with a GPS receiver. The EC measured with indirect calorimetry was higher in running with the ball (4.60±0.42 J/kg/m) than in normal running (4.19±0.33 J/kg/m), with a very likely moderate difference between conditions. Instead, a likely small difference was observed between conditions for EC estimated from GPS data (4.87±0.07 vs. 4.83±0.08 J/kg/m). This study sheds light on the energy expenditure of playing soccer, providing relevant data about the EC of a typical soccer-specific activity. These findings may be a reference for coaches to precisely determine the training load in drills with the ball, such as soccer-specific circuits or small-sided games. © Georg Thieme Verlag KG Stuttgart · New York.

Health-Related Physical Fitness in Healthy Untrained Men: Effects on VO2max, Jump Performance and Flexibility of Soccer and Moderate-Intensity Continuous Running

PubMed Central

Milanović, Zoran; Pantelić, Saša; Sporiš, Goran; Mohr, Magni; Krustrup, Peter

2015-01-01

The purpose of this study was to determine the effects of recreational soccer (SOC) compared to moderate-intensity continuous running (RUN) on all health-related physical fitness components in healthy untrained men. Sixty-nine participants were recruited and randomly assigned to one of three groups, of which sixty-four completed the study: a soccer training group (SOC; n = 20, 34±4 (means±SD) years, 78.1±8.3 kg, 179±4 cm); a running group (RUN; n = 21, 32±4 years, 78.0±5.5 kg, 179±7 cm); or a passive control group (CON; n = 23, 30±3 years, 76.6±12.0 kg, 178±8 cm). The training intervention lasted 12 weeks and consisted of three 60-min sessions per week. All participants were tested for each of the following physical fitness components: maximal aerobic power, minute ventilation, maximal heart rate, squat jump (SJ), countermovement jump with arm swing (CMJ), sit-and-reach flexibility, and body composition. Over the 12 weeks, VO2max relative to body weight increased more (p<0.05) in SOC (24.2%, ES = 1.20) and RUN (21.5%, ES = 1.17) than in CON (-5.0%, ES = -0.24), partly due to large changes in body mass (-5.9, -5.7 and +2.6 kg, p<0.05 for SOC, RUN and CON, respectively). Over the 12 weeks, SJ and CMJ performance increased more (p<0.05) in SOC (14.8 and 12.1%, ES = 1.08 and 0.81) than in RUN (3.3 and 3.0%, ES = 0.23 and 0.19) and CON (0.3 and 0.2%), while flexibility also increased more (p<0.05) in SOC (94%, ES = 0.97) than in RUN and CON (0–2%). In conclusion, untrained men displayed marked improvements in maximal aerobic power after 12 weeks of soccer training and moderate-intensity running, partly due to large decreases in body mass. Additionally soccer training induced pronounced positive effects on jump performance and flexibility, making soccer an effective broad-spectrum fitness training intervention. PMID:26305880

Effects of isolated or combined carbohydrate and caffeine supplementation between 2 daily training sessions on soccer performance.

PubMed

Andrade-Souza, Victor Amorim; Bertuzzi, Romulo; de Araujo, Gustavo Gomes; Bishop, David; Lima-Silva, Adriano Eduardo

2015-05-01

This study aimed to investigate whether isolated or combined carbohydrate (CHO) and caffeine (CAF) supplementation have beneficial effects on performance during soccer-related tests performed after a previous training session. Eleven male, amateur soccer players completed 4 trials in a randomized, double-blind, and crossover design. In the morning, participants performed the Loughborough Intermittent Shuttle Test (LIST). Then, participants ingested (i) 1.2 g·kg(-1) body mass·h(-1) CHO in a 20% CHO solution immediately after and 1, 2, and 3 h after the LIST; (ii) CAF (6 mg·kg(-1) body mass) 3 h after the LIST; (iii) CHO combined with CAF (CHO+CAF); and (iv) placebo. All drinks were taste-matched and flavourless. After this 4-h recovery, participants performed a countermovement jump (CMJ) test, a Loughborough Soccer Passing Test (LSPT), and a repeated-sprint test. There were no main effects of supplementation for CMJ, LSPT total time, or best sprint and total sprint time from the repeated-sprint test (p>0.05). There were also no main effects of supplementation for heart rate, plasma lactate concentration, rating of perceived exertion (RPE), pleasure-displeasure, and perceived activation (p>0.05). However, there were significant time effects (p<0.05), with heart rate, plasma lactate concentration, RPE, and perceived activation increasing with time, and pleasure-displeasure decreasing with time. In conclusion, isolated and/or combined CHO and CAF supplementation is not able to improve soccer-related performance tests when performed after a previous training session.

Shoe and Field Surface Risk Factors for Acute Lower Extremity Injuries Among Female Youth Soccer Players.

PubMed

OʼKane, John W; Gray, Kristen E; Levy, Marni R; Neradilek, Moni; Tencer, Allan F; Polissar, Nayak L; Schiff, Melissa A

2016-05-01

To describe acute lower extremity injuries and evaluate extrinsic risk factors in female youth soccer. Nested case-control study. Youth soccer clubs in Seattle, WA. Female soccer players (n = 351) ages 11 to 15 years randomly selected from 4 soccer clubs from which 83% of their players were enrolled with complete follow-up for 92% of players. Injured players were interviewed regarding injury, field surface, shoe type, and position. Uninjured controls, matched on game or practice session, were also interviewed. The association between risk factors and acute lower extremity injury using logistic regression to estimate odds ratios (OR) and 95% confidence intervals (CI). One hundred seventy-three acute lower extremity injuries occurred involving primarily the ankle (39.3%), knee (24.9%), and thigh (11.0%). Over half (52.9%) recovered within 1 week, whereas 30.2% lasted beyond 2 weeks. During practices, those injured were approximately 3-fold (OR, 2.83; 95% CI, 1.49-5.31) more likely to play on grass than artificial turf and 2.4-fold (95% CI, 1.03-5.96) more likely to wear cleats on grass than other shoe and surface combinations. During games, injured players were 89% (95% CI, 1.03-4.17) more likely to play defender compared with forward. Half of the acute lower extremity injuries affected the ankle or knee. Grass surface and wearing cleats on grass increased training injuries. The majority, 64%, of female youth soccer players' acute injuries involve the ankle and knee and injury prevention strategies in this age group should target these areas. When considering playing surfaces for training, communities and soccer organizations should consider the third-generation artificial turf a safe alternative to grass.

Motivational Traits of Elite Young Soccer Players

ERIC Educational Resources Information Center

Stewart, Craig; Meyers, Michael C.

2004-01-01

Among the most overlooked aspects in the development of elite young soccer players is that of specific psychological traits. Of those traits, motivation has important implications for programs whose objectives are identification and cultivation of young, skilled performers. The growth in popularity of soccer by youth and the successes experienced…

Yo-Yo Intermittent Recovery Test Level 2 and Its Relationship With Other Typical Soccer Field Tests in Female Collegiate Soccer Players.

PubMed

Lockie, Robert G; Jalilvand, Farzad; Moreno, Matthew R; Orjalo, Ashley J; Risso, Fabrice G; Nimphius, Sophia

2017-10-01

The ability to complete high-intensity running is essential for soccer. The Yo-Yo Intermittent Recovery Test Level 2 (YYIRT2) can measure this capacity, but there is limited information regarding this assessment in collegiate female soccer players. This study investigated the YYIRT2 as a measure of high-intensity running in this population, and its relationship to other soccer field tests. Twenty-one players from a Division I team were recruited. In addition to the YYIRT2, subjects completed linear (0-5, 0-10, and 0-30 m sprint intervals) and change-of-direction (pro-agility and 60-yard shuttle) speed tests, as well as the YYIRT Level 1 (YYIRT1), to assess relationships with YYIRT2 by correlations (p ≤ 0.05). The correlation of YYIRT1 with the speed tests was also assessed. The YYIRT1 and YYIRT2 were standardized using z-scores for comparison with elite benchmarks to investigate relative performance on each test. The YYIRT2 and YYIRT1 distances did not significantly correlate with those of the speed tests (r = -0.251 to 0.274). There was a large relationship between YYIRT2 and YYIRT1 distances (r = 0.582), although the explained variance was low (33.87%). Mean YYIRT2 z-scores (-4.29 ± 1.66) indicated a performance further from elite benchmarks than those of the YYIRT1 (-1.92 ± 1.61), and 90.5% (19 of 21) subjects performed relatively better in the YYIRT1 than YYIRT2. The YYIRT2 provided a more specific measure of high-intensity running to that of the YYIRT1 in collegiate female soccer players. Coaches may consider using the YYIRT2 to gauge and track progress of high-intensity running capabilities and create training programs to improve this ability in female players.

Evaluation of Seasonal Changes in Fitness, Anthropometrics, and Body Composition in Collegiate Division Ii Female Soccer Players.

PubMed

Peart, Ashley N; Nicks, Clayton R; Mangum, Michael; Tyo, Brian M

2018-03-22

The purpose of this study was to investigate anthropometrics, body composition, aerobic and anaerobic fitness of collegiate Division II female soccer players throughout a calendar year. Eighteen (20 ± 0.9y) NCAA division II female soccer players from the same team participated in the study. Anthropometrics and body composition variables were assessed in addition to the Counter Movement Jump (CMJ), Wingate Anaerobic Test (WAT), and peak oxygen uptake (VO2peak). Data were collected over five time points: end of competitive seasons (ECS1 and ECS2), beginning of off-season (BOS), end of off-season (EOS), and pre-season (PS). Repeated-measures analysis of variance (ANOVA) were conducted to compare test scores among all five data collection points. Where appropriate, Bonferroni post-hoc tests were used to determine which points were significantly different. Hip circumference (HC) decreased significantly (p < 0.001) from EOS (98.47 ± 6.5 cm) to PS (94.46 ± 6.8 cm). Fat mass (FM) (12.73 ± 5.4 kg) was significantly different in ECS2 compared to BOS and EOS means (p ≤ 0.05) and percentage of body fat (%BF) (20.08 ± 5.44) significantly different in ECS2 compared to ECS1, BOS, and EOS means (p ≤ 0.05), while fat-free mass (FFM) was maintained from ECS1 to ECS2. CMJ, WAT, and VO2peak performance did not significantly change from ECS1 to ECS2. Anthropometrics and body composition results are similar to previous studies measuring Division II to professional female soccer players. CMJ results remained consistent and are comparable to results on Division I female soccer players. Coaches and researchers can use these data to help design and evaluate training programs throughout a calendar year.

Aerial Rotation Effects on Vertical Jump Performance Among Highly Skilled Collegiate Soccer Players.

PubMed

Barker, Leland A; Harry, John R; Dufek, Janet S; Mercer, John A

2017-04-01

Barker, LA, Harry, JR, Dufek, JS, and Mercer, JA. Aerial rotation effects on vertical jump performance among highly skilled collegiate soccer players. J Strength Cond Res 31(4): 932-938, 2017-In soccer matches, jumps involving rotations occur when attempting to head the ball for a shot or pass from set pieces, such as corner kicks, goal kicks, and lob passes. However, the 3-dimensional ground reaction forces used to perform rotational jumping tasks are currently unknown. Therefore, the purpose of this study was to compare bilateral, 3-dimensional, and ground reaction forces of a standard countermovement jump (CMJ0) with those of a countermovement jump with a 180° rotation (CMJ180) among Division-1 soccer players. Twenty-four participants from the soccer team of the University of Nevada performed 3 trials of CMJ0 and CMJ180. Dependent variables included jump height, downward and upward phase times, vertical (Fz) peak force and net impulse relative to mass, and medial-lateral and anterior-posterior force couple values. Statistical significance was set a priori at α = 0.05. CMJ180 reduced jump height, increased the anterior-posterior force couple in the downward and upward phases, and increased upward peak Fz (p ≤ 0.05). All other variables were not significantly different between groups (p > 0.05). However, we did recognize that downward peak Fz trended lower in the CMJ0 condition (p = 0.059), and upward net impulse trended higher in the CMJ0 condition (p = 0.071). It was concluded that jump height was reduced during the rotational jumping task, and rotation occurred primarily via AP ground reaction forces through the entire countermovement jump. Coaches and athletes may consider additional rotational jumping in their training programs to mediate performance decrements during rotational jump tasks.

AMIC Cartilage Repair in a Professional Soccer Player

PubMed Central

Bark, S.; Riepenhof, H.; Gille, J.

2012-01-01

We report a case of a professional soccer player suffering from a traumatic cartilage lesion grade IV according to the Outerbridge classification at the femoral condyle treated with an enhanced microfracture technique (AMIC). Autologous Matrix-Induced Chondrogenesis (AMIC) is an innovative treatment for localized full-thickness cartilage defects combining the well-known microfracturing with collagen scaffold and fibrin glue. Because of the cartilage lesion (3 cm2), an AMIC procedure was performed followed by a rehabilitation program according to the protocols in the literature, (Steadman et al.; 2003). After 8 months of rehabilitation, the player returned to team training and after 10 months to competition. Altogether he returned to the same skill level for almost one year after the index operation. He is very satisfied with the clinical results after AMIC, which corresponds with the Lysholm score of 90 points at 12 months. PMID:23259120

Genomics DNA Profiling in Elite Professional Soccer Players: A Pilot Study

PubMed Central

Kambouris, M; Del Buono, A; Maffulli, N

2014-01-01

Functional variants in exonic regions have been associated with development of cardiovascular disease, diabetes and cancer. Athletic performance can be considered a multi-factorial complex phenotype. Genomic DNA was extracted from buccal swabs of seven soccer players from the Fulham football team. Single nucleotide polymorphism (SNPs) genotyping was undertaken. To achieve optimal athletic performance, predictive genomics DNA profiling for sports performance can be used to aid in sport selection and elaboration of personalized training and nutrition programs. Predictive DNA profiling may be able to detect athletes with potential or frank injuries, or screening and selection of future athletes, and can help them to maximize utilization of their potential and improve performance in sports. The aim of this study is to provide a wide scenario of specific genomic variants that an athlete carries, to implement which measures should be taken to maximize the athlete’s potential. PMID:24809029

DETERMINATION OF CLINICALLY RELEVANT DIFFERENCES IN FRONTAL PLANE HOP TESTS IN WOMEN'S COLLEGIATE BASKETBALL AND SOCCER PLAYERS

PubMed Central

Hardesty, Kelly; Hegedus, Eric J.; Ford, Kevin R.; Nguyen, Anh‐Dung

2017-01-01

Background ACL injury prevention programs are less successful in female basketball players than in soccer players. Previous authors have identified anthropometric and biomechanical differences between the athletes and different sport‐specific demands, including a higher frequency of frontal plane activities in basketball. Current injury risk screening and preventive training practices do not place a strong emphasis on frontal plane activities. The medial and lateral triple hop for distance tests may be beneficial for use in the basketball population. Hypothesis/Purpose To 1) establish normative values for the medial and lateral triple hop tests in healthy female collegiate athletes, and 2) analyze differences in test scores between female basketball and soccer players. It was hypothesized that due to the frequent frontal plane demands of their sport, basketball players would exhibit greater performance during these frontal plane performance tests. Study Design Cross‐sectional. Methods Thirty‐two NCAA Division‐1 female athletes (20 soccer, 12 basketball) performed three trials each of a medial and lateral triple hop for distance test. Distances were normalized to height and mass in order to account for anthropometric differences. Repeated measures ANOVAs were performed to identify statistically significant main effects of sport (basketball vs. soccer), and side (right vs. left), and sport x side interactions. Results After accounting for anthropometric differences, soccer players exhibited significantly better performance than basketball players in the medial and lateral triple hop tests (p < 0.05). Significant side differences (p = 0.02) were identified in the entire population for the medial triple hop test, such that participants jumped farther on their left (400.3 ± 41.5 cm) than right (387.9 ± 43.4 cm) limbs, but no side differences were identified in the lateral triple hop. No significant side x sport interactions were identified. Conclusions Women's basketball players exhibit decreased performance of frontal plane hop tests when compared to women's soccer players. Additionally, the medial triple hop for distance test may be effective at identifying side‐to‐side asymmetries Level of Evidence 3 PMID:28515972

Effects of Plyometric and Resistance Training on Muscle Strength, Explosiveness and Neuromuscular Function in Young Adolescent Soccer Players.

PubMed

McKinlay, Brandon John; Wallace, Phillip; Dotan, Raffy; Long, Devon; Tokuno, Craig; Gabriel, David; Falk, Bareket

2018-01-04

This study examined the effect of 8-weeks of free-weight-resistance (RT) and plyometric (PLYO) training on maximal strength, explosiveness and jump performance compared with no added training (CON), in young male soccer players. Forty-one 11[FIGURE DASH]13-year-old soccer players were divided into three groups (RT, PLYO, CON). All participants completed isometric and dynamic (240°/s) knee extensions pre- and post-training. Peak torque (pT), peak rate of torque development (pRTD), electromechanical-delay (EMD), rate of muscle activation (Q50), m. vastus-lateralis thickness (VLT), and jump performance were examined. pT, pRTD and jump performance significantly improved in both training groups. Training resulted in significant (p<0.05) increases in isometric pT (23.4 vs. 15.8%) and pRTD (15.0 vs. 17.6%), in RT and PLYO, respectively. During dynamic contractions, training resulted in significant increases in pT (12.4 and 10.8% in RT and PLYO, respectively), but not pRTD. Jump performance increased in both training groups (RT=10.0%, PLYO=16.2%), with only PLYO significantly different from CON. Training resulted in significant increases in VLT (RT=6.7%. PLYO=8.1%). There were no significant EMD changes. In conclusion, 8-week free-weight resistance and plyometric training resulted in significant improvements in muscle strength and jump performance. Training resulted in similar muscle hypertrophy in the two training modes, with no clear differences in muscle performance. Plyometric training was more effective in improving jump performance, while free-weight resistance training was more advantageous in improving peak torque, where the stretch reflex was not involved.

Level of functional capacities following soccer-specific warm-up methods among elite collegiate soccer players.

PubMed

Vazini Taher, Amir; Parnow, Abdolhossein

2017-05-01

Different methods of warm-up may have implications in improving various aspects of soccer performance. The present study aimed to investigate acute effects of soccer specific warm-up protocols on functional performance tests. This study using randomized within-subject design, investigated the performance of 22 collegiate elite soccer player following soccer specific warm-ups using dynamic stretching, static stretching, and FIFA 11+ program. Post warm-up examinations consisted: 1) Illinois Agility Test; 2) vertical jump; 3) 30 meter sprint; 4) consecutive turns; 5) flexibility of knee. Vertical jump performance was significantly lower following static stretching, as compared to dynamic stretching (P=0.005). Sprint performance declined significantly following static stretching as compared to FIFA 11+ (P=0.023). Agility time was significantly faster following dynamic stretching as compared to FIFA 11+ (P=0.001) and static stretching (P=0.001). Knee flexibility scores were significantly improved following the static stretching as compared to dynamic stretching (P=016). No significant difference was observed for consecutive turns between three warm-up protocol. The present finding showed that a soccer specific warm-up protocol relied on dynamic stretching is preferable in enhancing performance as compared to protocols relying on static stretches and FIFA 11+ program. Investigators suggest that while different soccer specific warm-up protocols have varied types of effects on performance, acute effects of dynamic stretching on performance in elite soccer players are assured, however application of static stretching in reducing muscle stiffness is demonstrated.

An interval kicking progression for return to soccer following lower extremity injury.

PubMed

Arundale, Amelia; Silvers, Holly; Logerstedt, David; Rojas, Jaime; Snyder-Mackler, Lynn

2015-02-01

The majority of all soccer injuries affect the lower extremities. Regardless of whether the injured limb is an athlete's preferred kicking or stance leg, a lower extremity injury may affect their ability to impact the ball. Sport-specific biomechanical progressions to augment loading and gradually reintroduce a player to the demands of sport have been developed for upper extremity sports such as baseball, softball, tennis, and golf. Generalized return to soccer progressions have also been published in order to assist clinicians in safely returning athletes to sport; however, there are no specific progressions for the early stages of kicking designed to introduce stance leg loading and kicking leg impact. Thus, the purpose of this clinical commentary was to review the existing literature elucidating the biomechanics of kicking a soccer ball and propose a progressive kicking program to support clinicians in safely returning their soccer athletes to the demands of sport. The interval kicking program (IKP) describes clinical guidelines for readiness to begin a kicking program as well as possible readiness to return to sport measures. The program is performed on alternate days integrating therapeutic exercise and cardiovascular fitness. The IKP gradually introduces a player to the loading and impact of kicking. The progression increases kicking distance (using the markings of a soccer field as a guide), volume, and intensity and uses proposed soreness rules, effusion guidelines, and player feedback in order to assist clinicians in determining readiness for advancement though the stages. The IKP also recommends utility of specific tests and measures to determine readiness for return to sport. Gradual reintroduction to sport specific demands is essential for a safe return to soccer. This return to sport progression provides a framework integrating injury specific therapeutic exercise, cardiovascular fitness, and the return to kicking progression, to assist clinicians in initiating an athletes' return to soccer. Level 5.

Effect of Progressive Volume-Based Overload During Plyometric Training on Explosive and Endurance Performance in Young Soccer Players.

PubMed

Ramírez-Campillo, Rodrigo; Henríquez-Olguín, Carlos; Burgos, Carlos; Andrade, David C; Zapata, Daniel; Martínez, Cristian; Álvarez, Cristian; Baez, Eduardo I; Castro-Sepúlveda, Mauricio; Peñailillo, Luis; Izquierdo, Mikel

2015-07-01

The purpose of the study was to compare the effects of progressive volume-based overload with constant volume-based overload on muscle explosive and endurance performance adaptations during a biweekly short-term (i.e., 6 weeks) plyometric training intervention in young soccer players. Three groups of young soccer players (age 13.0 ± 2.3 years) were divided into: control (CG; n = 8) and plyometric training with (PPT; n = 8) and without (NPPT; n = 8) a progressive increase in volume (i.e., 16 jumps per leg per week, with an initial volume of 80 jumps per leg each session). Bilateral and unilateral horizontal and vertical countermovement jump with arms (CMJA), 20-cm drop jump reactive strength index (RSI20), maximal kicking velocity (MKV), 10-m sprint, change of direction speed (CODS), and Yo-Yo intermittent recovery level 1 test (Yo-Yo IR1) were measured. Although both experimental groups significantly increased CMJA, RSI20, CODS, and endurance performance, only PPT showed a significant improvement in MKV and 10-m sprint time. In addition, only PPT showed a significantly higher performance improvement in jumping, MKV, and Yo-Yo IR1 compared with CG. Also, PPT showed higher meaningful improvement compared with NPPT in all (except 1) jump performance measures. Furthermore, although PPT involved a higher total volume compared with NPPT, training efficiency (i.e., percentage change in performance/total jump volume) was similar between groups. Our results show that PPT and NPPT ensured significant improvement in muscle explosive and endurance performance measures. However, a progressive increase in plyometric training volume seems more advantageous to induce soccer-specific performance improvements.

Nutrient intake and blood iron status of male collegiate soccer players.

PubMed

Noda, Yuka; Iide, Kazuhide; Masuda, Reika; Kishida, Reina; Nagata, Atsumi; Hirakawa, Fumiko; Yoshimura, Yoshitaka; Imamura, Hiroyuki

2009-01-01

The purpose of this study was: 1) to collect baseline data on nutrient intake in order to advise athletes about nutrition practices that might enhance performance, and 2) to evaluate the dietary iron intake and blood iron status of Japanese collegiate soccer players. The subjects were 31 soccer players and 15 controls. Dietary information was obtained with a food frequency questionnaire. The mean carbohydrate (6.9 g.kg-1 BW) and protein (1.3 g/kg) intakes of the soccer players were marginal in comparisons with recommended targets. The mean intakes of calcium, magnesium, vitamin A, B1, B2, and C were lower than the respective Japanese recommended dietary allowances (RDAs) or adequate dietary intakes in the soccer players. The mean intakes of green and other vegetables, milk and dairy products, fruits, and eggs were lower than the recommended targets. Thus, we recommended athletes to increase the intake of these foodstuffs along with slight increase in carbohydrate and lean meat. The mean intake of iron was higher than the respective RDA in the soccer players. A high prevalence of hemolysis (71%) in the soccer players was found. None of the soccer players and controls had anemia. Two soccer players had iron depletion, while none was found in the controls. In those players who had iron deficiency, the training load need to be lowered and/or iron intake may be increased.

Training for Power and Speed: Effects of Increasing or Decreasing Jump Squat Velocity in Elite Young Soccer Players.

PubMed

Loturco, Irineu; Nakamura, Fabio Y; Kobal, Ronaldo; Gil, Saulo; Abad, César C Cal; Cuniyochi, Rogério; Pereira, Lucas A; Roschel, Hamilton

2015-10-01

The aim of this study was to test the effects of 2 different velocity-oriented power training regimens by either increasing or decreasing the jump squat velocity during jump training sessions applied 3 times a week for 6 weeks in soccer players. Twenty-four elite under-20 soccer players were randomly assigned to an increased bar velocity group (IVG) or a reduced bar velocity group (RVG). Athletes had their countermovement jump heights, mean propulsive velocities (MPVs) in jump squat, leg press maximum dynamic strength (1 repetition maximum [RM]), 20-m sprint times, and zig-zag change of direction (COD) abilities assessed before and after the intervention. Performance in all tests improved after training in both groups. However, greater gains in 1RM and MPV using 50-90% of body mass (BM) were noted for the RVG. The IVG demonstrated greater improvements in speed at 5, 10, and 20 m and MPV with no additional external load and with 40% BM. Both groups improved similarly in countermovement jumps and COD. To conclude, both velocity-oriented power training regimens were effective in eliciting neuromechanical adaptations, leading to better strength/power/speed performances, and the choice as to the most suitable method should be tailored according to players' needs/deficiencies.

Effects of awareness interventions on children's attitudes toward peers with a visual impairment.

PubMed

Reina, Raul; López, Víctor; Jiménez, Mario; García-Calvo, Tomás; Hutzler, Yeshayahu

2011-09-01

The purpose of this study was to explore the effect of two awareness programs (6-day vs. 1-day programs) on children's attitudes toward peers with a visual impairment. Three hundred and forty-four Spanish physical education students (164 girls and 180 boys) aged 10-15 years, took part in the study. A modified version of the Attitudes Toward Disability Questionnaire (ATDQ) was used, which includes three sub-scales: (i) cognitive perceptions, (ii) emotional perception, and (iii) behavioral readiness to interact with children with disabilities. The questionnaire was filled out during the regular physical education class before and immediately after the awareness activity. The 6-day didactical unit included a lecture on visual impairments and a video describing visual impairments and the game of 5-a-side soccer (first lesson), sensibilization activities toward visual impairment (second and third lessons), training and competitive 5-a-side soccer tasks using blindfolded goggles (fourth and fifth lessons), and a sport show and chat with soccer players with a visual impairment (sixth lesson). The 1-day awareness unit only included the final session of the didactical activity. Repeated measures analysis of variance revealed significant time effects in the cognitive, emotional, and behavioral subscales. Sex also was found to demonstrate significant effects, in which women showed more favorable results than men. A time-by-group intervention effect was only demonstrated in the cognitive sub-scale, and the 6-day didactic intervention was more effective than the 1-day awareness unit.

Dynamic balance sensory motor control and symmetrical or asymmetrical equilibrium training.

PubMed

Guillou, Emmanuel; Dupui, Philippe; Golomer, Eveline

2007-02-01

Determine whether symmetrical or asymmetrical equilibrium training can enhance the proprioceptive input of the left versus right supporting leg (SL) motor control. Proprioceptive input was tested using a seesaw platform through a cross-sectional study. The total spectral energy was recorded and divided into 0-2 and 2-20Hz frequency bands. Experts in asymmetrical tasks (soccer players) were compared to experts in symmetrical tasks (dancers, acrobats) and untrained subjects according to pitch versus roll imbalance direction on each SL. Regarding the low frequency band, spectral energy values were lower for experts than for untrained subjects in the roll direction only, whatever the SL (p<0.05). Regarding the high frequency band, spectral energy values were lower for the left SL compared to the right one for soccer players only (p<0.05). Furthermore, soccer players also exhibited lower values than other subjects on the left SL. Asymmetrical equilibrium training minimizes the proprioceptive input, emphasizing the role of the biomechanical component in postural regulation. Testing athletes on a spontaneous unstable platform is a way to accurately discriminate each SL performance for one type of sport training. In sport medicine rehabilitation, injured SL could be detected with this protocol comparing it with healthy SL.

Sequencing Effects of Balance and Plyometric Training on Physical Performance in Youth Soccer Athletes.

PubMed

Hammami, Raouf; Granacher, Urs; Makhlouf, Issam; Behm, David G; Chaouachi, Anis

2016-12-01

Hammami, R, Granacher, U, Makhlouf, I, Behm, DG, and Chaouachi, A. Sequencing effects of balance and plyometric training on physical performance in youth soccer athletes. J Strength Cond Res 30(12): 3278-3289, 2016-Balance training may have a preconditioning effect on subsequent power training with youth. There are no studies examining whether the sequencing of balance and plyometric training has additional training benefits. The objective was to examine the effect of sequencing balance and plyometric training on the performance of 12- to 13-year-old athletes. Twenty-four young elite soccer players trained twice per week for 8 weeks either with an initial 4 weeks of balance training followed by 4 weeks of plyometric training (BPT) or 4 weeks of plyometric training proceeded by 4 weeks of balance training (PBT). Testing was conducted pre- and posttraining and included medicine ball throw; horizontal and vertical jumps; reactive strength; leg stiffness; agility; 10-, 20-, and 30-m sprints; Standing Stork balance test; and Y-Balance test. Results indicated that BPT provided significantly greater improvements with reactive strength index, absolute and relative leg stiffness, triple hop test, and a trend for the Y-Balance test (p = 0.054) compared with PBT. Although all other measures had similar changes for both groups, the average relative improvement for the BPT was 22.4% (d = 1.5) vs. 15.0% (d = 1.1) for the PBT. BPT effect sizes were greater with 8 of 13 measures. In conclusion, although either sequence of BPT or PBT improved jumping, hopping, sprint acceleration, and Standing Stork and Y-Balance, BPT initiated greater training improvements in reactive strength index, absolute and relative leg stiffness, triple hop test, and the Y-Balance test. BPT may provide either similar or superior performance enhancements compared with PBT.

Integrating the internal and external training loads in soccer.

PubMed

Akubat, Ibrahim; Barrett, Steve; Abt, Grant

2014-05-01

This study aimed to assess the relationships of fitness in soccer players with a novel integration of internal and external training load (TL). Ten amateur soccer players performed a lactate threshold (LT) test followed by a soccer simulation (Ball-Sport Endurance and Sprint Test [BEAST90mod]). The results from the LT test were used to determine velocity at lactate threshold (vLT), velocity at onset of blood lactate accumulation (vOBLA), maximal oxygen uptake (VO2max), and the heart rate-blood lactate profile for calculation of internal TL (individualized training impulse, or iTRIMP). The total distance (TD) and high intensity distance (HID) covered during the BEAST90mod were measured using GPS technology that allowed measurement of performance and external TL. The internal TL was divided by the external TL to form TD:iTRIMP and HID:iTRIMP ratios. Correlation analyses assessed the relationships between fitness measures and the ratios to performance in the BEAST90mod. vLT, vOBLA, and VO2max showed no significant relationship to TD or HID. HID:iTRIMP significantly correlated with vOBLA (r = .65, P = .04; large), and TD:iTRIMP showed a significant correlation with vLT (r = .69, P = .03; large). The results suggest that the integrated use of ratios may help in the assessment of fitness, as performance alone showed no significant relationships with fitness.

Within Session Sequence of Balance and Plyometric Exercises Does Not Affect Training Adaptations with Youth Soccer Athletes

PubMed Central

Chaouachi, Mehdi; Granacher, Urs; Makhlouf, Issam; Hammami, Raouf; Behm, David G; Chaouachi, Anis

2017-01-01

The integration of balance and plyometric training has been shown to provide significant improvements in sprint, jump, agility, and other performance measures in young athletes. It is not known if a specific within session balance and plyometric exercise sequence provides more effective training adaptations. The objective of the present study was to investigate the effects of using a sequence of alternating pairs of exercises versus a block (series) of all balance exercises followed by a block of plyometric exercises on components of physical fitness such as muscle strength, power, speed, agility, and balance. Twenty-six male adolescent soccer players (13.9 ± 0.3 years) participated in an 8-week training program that either alternated individual balance (e.g., exercises on unstable surfaces) and plyometric (e.g., jumps, hops, rebounds) exercises or performed a block of balance exercises prior to a block of plyometric exercises within each training session. Pre- and post-training measures included proxies of strength, power, agility, sprint, and balance such as countermovement jumps, isometric back and knee extension strength, standing long jump, 10 and 30-m sprints, agility, standing stork, and Y-balance tests. Both groups exhibited significant, generally large magnitude (effect sizes) training improvements for all measures with mean performance increases of approximately >30%. There were no significant differences between the training groups over time. The results demonstrate the effectiveness of combining balance and plyometric exercises within a training session on components of physical fitness with young adolescents. The improved performance outcomes were not significantly influenced by the within session exercise sequence. Key points The combination of balance and plyometric exercises can induce significant and substantial training improvements in muscle strength, power, speed, agility, and balance with adolescent youth athletes The within training session sequence of balance and plyometric exercises does not substantially affect these training improvements. PMID:28344461

Seasonal Variation in Objectively Assessed Physical Activity among Young Norwegian Talented Soccer Players: A Description of Daily Physical Activity Level

PubMed Central

Sæther, Stig A.; Aspvik, Nils P.

2014-01-01

‘Practise makes perfect’ is a well-known expression in most sports, including top-level soccer. However, a high training and match load increases the risk for injury, overtraining and burnout. With the use of accelerometers and a self-report questionnaire, the aim of this study was to describe talented players’ physical activity (PA) level. Data were collected three times during the 2011 Norwegian Football season (March, June and October). The accelerometer output, counts·min–1 (counts per unit time registered), reports the daily PA-level for young talented soccer players. Results showed a stable PA-level across the season (March: 901.2 counts·min–1, June: 854.9 counts·min–1, October: 861.5 counts·min–1). Furthermore, comparison of five different training sessions across the season showed that the PA-level ranged from 2435.8 to 3745.4 counts·min–1. A one-way ANOVA showed no significant differences between the three measured weeks during the soccer season (p≤0.814). However, the training sessions in January had a significantly higher PA-level than those in June and October (p≤0.001). Based on these results, we discuss how potential implications of PA-level affect factors such as risk of injury, overtraining and burnout. We argue that player development must be seen as part of an overall picture in which club training and match load should be regarded as one of many variables influencing players’ PA-level. Key points It is well established that to achieve a high performance level in sport, one must implement a high training and match load in childhood and youth. With the use of accelerometers and a self-reported questionnaire, the aim of this study was to describe talented players’ total physical activity (PA) load. These results indicate that young talented soccer players must overcome large doses of PA on a weekly basis, exposing them to a high risk of injury, overtraining and burnout. PMID:25435792

Seasonal Variation in Objectively Assessed Physical Activity among Young Norwegian Talented Soccer Players: A Description of Daily Physical Activity Level.

PubMed

Sæther, Stig A; Aspvik, Nils P

2014-12-01

'Practise makes perfect' is a well-known expression in most sports, including top-level soccer. However, a high training and match load increases the risk for injury, overtraining and burnout. With the use of accelerometers and a self-report questionnaire, the aim of this study was to describe talented players' physical activity (PA) level. Data were collected three times during the 2011 Norwegian Football season (March, June and October). The accelerometer output, counts·min(-1) (counts per unit time registered), reports the daily PA-level for young talented soccer players. Results showed a stable PA-level across the season (March: 901.2 counts·min(-1), June: 854.9 counts·min(-1), October: 861.5 counts·min(-1)). Furthermore, comparison of five different training sessions across the season showed that the PA-level ranged from 2435.8 to 3745.4 counts·min(-1). A one-way ANOVA showed no significant differences between the three measured weeks during the soccer season (p≤0.814). However, the training sessions in January had a significantly higher PA-level than those in June and October (p≤0.001). Based on these results, we discuss how potential implications of PA-level affect factors such as risk of injury, overtraining and burnout. We argue that player development must be seen as part of an overall picture in which club training and match load should be regarded as one of many variables influencing players' PA-level. Key pointsIt is well established that to achieve a high performance level in sport, one must implement a high training and match load in childhood and youth.With the use of accelerometers and a self-reported questionnaire, the aim of this study was to describe talented players' total physical activity (PA) load.These results indicate that young talented soccer players must overcome large doses of PA on a weekly basis, exposing them to a high risk of injury, overtraining and burnout.

Sleep quality and high intensity interval training at two different times of day: A crossover study on the influence of the chronotype in male collegiate soccer players.

PubMed

Vitale, Jacopo A; Bonato, Matteo; Galasso, Letizia; La Torre, Antonio; Merati, Giampiero; Montaruli, Angela; Roveda, Eliana; Carandente, Franca

2017-01-01

The influence of the chronotype on the sleep quality in male collegiate soccer players in response to acute high intensity interval training (HIIT) performed at two different times of day was evaluated. The sleep quality was poorer in the morning-type than in the evening-type players after the evening HIIT session, whereas no significant changes in the sleep quality of the two chronotypes after the morning HIIT session was observed. The results suggest that an athlete's chronotype should be taken into account when scheduling training sessions and to promote faster recovery processes.

Oxidative stress status in elite athletes engaged in different sport disciplines.

PubMed

Hadžović-Džuvo, Almira; Valjevac, Amina; Lepara, Orhan; Pjanić, Samra; Hadžimuratović, Adnan; Mekić, Amel

2014-05-01

Exercise training may increase production of free radicals and reactive oxygen species in different ways. The training type and intensity may influence free radicals production, which leads to differences in oxidative stress status between athletes, but the results of the previous studies are incosistent. The aim of our study was to estimate oxidative stress status in elite athletes engaged in different sport disciplines. The study included 39 male highly skilled professional competitors with international experience (2 Olympic players): 12 wrestlers, 14 soccer players and 13 basketball players in whom we determined the levels of advanced oxidation protein products (AOPP) and malondialdehyde (MDA), as markers of oxidative stress and the total antioxidative capacity (ImAnOX) using commercially available assay kits. The mean AOPP concentration was not significantly different between soccer players, wrestler and basketball players (60.0 ± 23.0 vs. 68.5 ± 30.8 and 80.72 ± 29.1 μmol/L respectively). Mean ImAnOX concentration was not different between soccer players (344.8 ± 35.6 μmol/L), wrestlers (342.5 ± 36.2 μmol/L) and basketball players (347.95 ± 31.3 μmol/L). Mean MDA concentration was significantly higher in basketball players (1912.1 ± 667.7 ng/mL) compared to soccer players (1060.1 ± 391.0 ng/mL, p=0.003). In spite of this fact, oxidative stress markers levels were increased compared to referral values provided by the manufacturer. Type of sports (soccer, wrestler or basketball) have no impact on the levels of oxidative stress markers. Elite sports engagement is a potent stimulus of oxidative stress that leads to the large recruitment of antioxidative defense. Oxidative stress status monitoring followed by appropriate use of antioxidants is recommended as a part of training regime.

Economic impact study: neuromuscular training reduces the burden of injuries and costs compared to standard warm-up in youth soccer.

PubMed

Marshall, Deborah A; Lopatina, Elena; Lacny, Sarah; Emery, Carolyn A

2016-11-01

There is randomised controlled trial (RCT) evidence that neuromuscular training (NMT) programmes can reduce the risk of injury in youth soccer. We evaluated the cost-effectiveness of such an NMT prevention strategy compared to a standard of practice warm-up. A cost-effectiveness analysis was conducted alongside a cluster RCT. Injury incidence rates were adjusted for cluster using Poisson regression analyses. Direct healthcare costs and injury incidence proportions were adjusted for cluster using bootstrapping. The joint uncertainty surrounding the cost and injury rate and proportion differences was estimated using bootstrapping with 10 000 replicates. Along with a 38% reduction in injury risk (rate difference=-1.27/1000 player hours (95% CI -0.33 to -2.2)), healthcare costs were reduced by 43% in the NMT group (-$689/1000 player hours (95% CI -$1741 to $234)) compared with the control group. 90% of the bootstrapped ratios were in the south-west quadrant of the cost-effectiveness plane, showing that the NMT programme was dominant (more effective and less costly) over standard warm-up. Projecting results onto 58 100 Alberta youth soccer players, an estimated 4965 injuries and over $2.7 million in healthcare costs would be conservatively avoided in one season with implementation of a neuromuscular training prevention programme. Implementation of an NMT prevention programme in youth soccer is effective in reducing the burden of injury and leads to considerable reduction in costs. These findings inform practice and policy supporting the implementation of NMT prevention strategies in youth soccer nationally and internationally. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Pre- and post-season dietary intake, body composition, and performance indices of NCAA division I female soccer players.

PubMed

Clark, Mandy; Reed, Debra B; Crouse, Stephen F; Armstrong, Robert B

2003-09-01

Little published data describe the dietary and physiological profiles of intercollegiate female soccer players; therefore, the purpose of this investigation was to report baseline dietary data, anthropometrics, and performance indices of soccer women during rigorous pre-season training (2 sessions/day) and then during the post-competitive season. Members of a NCAA Division I women's soccer squad completed 3-day diet records, anthropometrics, and physical tests, including VO2peak. Average body mass was 62 kg with 16% body fat, and no significant pre to post differences were observed. Total energy, carbohydrate (CHO), protein, and fat intakes were significantly greater during the pre-season. Pre-season energy intake met the DRI for females with an "active" lifestyle (37 kcal/kg). While CHO intake failed to meet minimum recommendations to promote glycogen repletion (7-10 g/kg), protein and fat intakes were above minimum recommendations. Pre- and post-season intakes of several micronutrients were marginal (<75% of the DRI) including vitamin E, folate, copper, and magnesium. VO2peak significantly improved from pre- to post-season (42 and 50 ml/kg/min). In this study female soccer players appeared to meet caloric needs during periods of training but failed to meet minimum CHO and micronutrient recommendations. Foods higher in protein and fat displaced more CHO-rich and nutrient-dense foods within athletes' energy requirements and satiety limits.

Differential Learning as a Key Training Approach to Improve Creative and Tactical Behavior in Soccer.

PubMed

Santos, Sara; Coutinho, Diogo; Gonçalves, Bruno; Schöllhorn, Wolfgang; Sampaio, Jaime; Leite, Nuno

2018-03-01

The aim of this study was to identify the effects of a differential-learning program, embedded in small-sided games, on the creative and tactical behavior of youth soccer players. Forty players from under-13 (U13) and under-15 (U15) were allocated into control and experimental groups and were tested using a randomized pretest to posttest design using small-sided games situations. The experimental group participated in a 5-month differential-learning program embodied in small-sided games situations, while the control group participated in a typical small-sided games training program. In-game creativity was assessed through notational analyses of the creative components, and the players' positional data were used to compute tactical-derived variables. The findings suggested that differential learning facilitated the development of creative components, mainly concerning attempts (U13, small; U15, small), versatility (U13, moderate; U15, small), and originality (U13, unclear; U15, small) of players' actions. Likewise, the differential-learning approach provided a decrease in fails during the game in both experimental groups (moderate). Moreover, differential learning seemed to favor regularity in pitch-positioning behavior for the distance between players' dyads (U13, small; U15, small), the distance to the team target (U13, moderate; U15, small), and the distance to the opponent target (U13, moderate; U15, small). The differential-learning program stressed creative and positional behavior in both age groups with a distinct magnitude of effects, with the U13 players demonstrating higher improvements over the U15 players. Overall, these findings confirmed that the technical variability promoted by differential learning nurtures regularity of positioning behavior.

Muscle Contraction Velocity: A Suitable Approach to Analyze the Functional Adaptations in Elite Soccer Players.

PubMed

Loturco, Irineu; Pereira, Lucas A; Kobal, Ronaldo; Kitamura, Katia; Ramírez-Campillo, Rodrigo; Zanetti, Vinicius; Abad, Cesar C Cal; Nakamura, Fabio Y

2016-09-01

Tensiomyography (TMG) has been used as a simple and non-invasive tool to assess the mechanical properties of skeletal muscles. The TMG-derived velocity of contraction (Vc), which can be calculated from the ratio between maximal radial displacement and the sum of contraction time and delay time, has been proposed for evaluating athletes. However, its sensitivity to training effects and possible relation with changes in soccer players' neuromuscular performance have not yet been addressed. To test this possibility, twenty-two male Brazilian elite soccer players were assessed using TMG-derived Vc, unloaded squat jump, countermovement jump and drop jump at 45 cm, loaded jump squat and linear (20 m) and change of direction (COD) sprint tests, prior to and after an 8-week period, between two consecutive official tournaments, during which the concurrency between endurance and strength-power training commonly impairs neuromuscular capacities. Magnitude-based inference was used to detect meaningful training effects. From pre- to post-tests, it was observed likely to a lmost certainly improvements in all modes of jumping tests. In addition, we could verify decrements in the 20-m and COD sprint performances, which were rated as very likely and almost certainly , respectively. Finally, both rectus femoris and biceps femoris muscles presented a likely reduction in Vc. Therefore, chronic decreases in sprinting speed are possibly accompanied by a reduced TMG-derived Vc. From a practical standpoint, the TMG-derived Vc can be used to monitor negative specific-soccer training effects related to potential impairments in maximum speed.

Oxidative stress and antioxidant biomarker responses after a moderate-intensity soccer training session.

PubMed

Mello, Rodrigo; Mello, Ricardo; Gomes, Diego; Paz, Gabriel Andrade; Nasser, Igor; Miranda, Humberto; Salerno, Verônica P

2017-01-01

The present study investigated the effects of a moderate-intensity soccer training session on the production of reactive oxygen species (ROS) and the antioxidant capacity in athletes along with the biomarkers creatine kinase and transaminases for lesions in muscle and liver cells. Twenty-two male soccer players participated in this study. Blood samples were collected 5 min before and after a moderate-intensity game simulation. The results showed a decrease in the concentration of reduced glutathione (GSH) from an elevation in the production of ROS that maintained the redox homeostasis. Although the session promoted an elevated energy demand, observed by an increase in lactate and glucose levels, damage to muscle and/or liver cells was only suggested by a significant elevation in the levels of alanine transaminase (ALT). Of the two biomarkers analysed, the results suggest that measurements of the ALT levels could be adopted as a method to monitor recovery in athletes.

The effects of progressive muscle relaxation and autogenic relaxation on young soccer players' mood states.

PubMed

Hashim, Hairul Anuar; Hanafi Ahmad Yusof, Hazwani

2011-06-01

This study was designed to compare the effects of two different relaxation techniques, namely progressive muscle relaxation (PMR) and autogenic relaxation (AGR) on moods of young soccer players. sixteen adolescent athletes (mean age: 14.1 ± 1.3) received either PMR or AGR training. Using Profile of Mood States- Adolescents, their mood states were measured one week before relaxation training, before the first relaxation session, and after the twelfth relaxation session. Mixed ANOVA revealed no significant interaction effects and no significant main effects in any of the subscales. However, significant main effects for testing sessions were found for confusion, depression, fatigue, and tension subscales. Post hoc tests revealed post-intervention reductions in the confusion, depression, fatigue, and tension subscale scores. These two relaxation techniques induce equivalent mood responses and may be used to regulate young soccer players' mood states.

The Effects of Progressive Muscle Relaxation and Autogenic Relaxation on Young Soccer Players’ Mood States

PubMed Central

Hashim, Hairul Anuar; Hanafi@Ahmad Yusof, Hazwani

2011-01-01

Purpose This study was designed to compare the effects of two different relaxation techniques, namely progressive muscle relaxation (PMR) and autogenic relaxation (AGR) on moods of young soccer players. Methods Sixteen adolescent athletes (mean age: 14.1 ± 1.3) received either PMR or AGR training. Using Profile of Mood States- Adolescents, their mood states were measured one week before relaxation training, before the first relaxation session, and after the twelfth relaxation session. Results Mixed ANOVA revealed no significant interaction effects and no significant main effects in any of the subscales. However, significant main effects for testing sessions were found for confusion, depression, fatigue, and tension subscales. Post hoc tests revealed post-intervention reductions in the confusion, depression, fatigue, and tension subscale scores. Conclusion These two relaxation techniques induce equivalent mood responses and may be used to regulate young soccer players’ mood states. PMID:22375225

Winning in NCAA Women?s Soccer: Does the Gender of the Coach Matter?

ERIC Educational Resources Information Center

Brush, Brian C.; Naples, Gregory J.

2011-01-01

While women's intercollegiate soccer has grown rapidly over the past three decades, men still hold nearly two-thirds of all head coaching positions in NCAA Division I women's soccer programs. This paper explores whether the gender of the head coach affects success in winning games. After considering various reasons why gender might matter, we…

Strong correlation of maximal squat strength with sprint performance and vertical jump height in elite soccer players

PubMed Central

Wisloff, U; Castagna, C; Helgerud, J; Jones, R; Hoff, J

2004-01-01

Background: A high level of strength is inherent in elite soccer play, but the relation between maximal strength and sprint and jumping performance has not been studied thoroughly. Objective: To determine whether maximal strength correlates with sprint and vertical jump height in elite male soccer players. Methods: Seventeen international male soccer players (mean (SD) age 25.8 (2.9) years, height 177.3 (4.1) cm, weight 76.5 (7.6) kg, and maximal oxygen uptake 65.7 (4.3) ml/kg/min) were tested for maximal strength in half squats and sprinting ability (0–30 m and 10 m shuttle run sprint) and vertical jumping height. Result: There was a strong correlation between maximal strength in half squats and sprint performance and jumping height. Conclusions: Maximal strength in half squats determines sprint performance and jumping height in high level soccer players. High squat strength did not imply reduced maximal oxygen consumption. Elite soccer players should focus on maximal strength training, with emphasis on maximal mobilisation of concentric movements, which may improve their sprinting and jumping performance. PMID:15155427

Nutritional Status and Daytime Pattern of Protein Intake on Match, Post-Match, Rest and Training Days in Senior Professional and Youth Elite Soccer Players.

PubMed

Bettonviel A, E O; Brinkmans N, Y J; Russcher, Kris; Wardenaar, Floris C; Witard, Oliver C

2016-06-01

The nutritional status of elite soccer players across match, postmatch, training and rest days has not been defined. Recent evidence suggests the pattern of dietary protein intake impacts the daytime turnover of muscle proteins and, as such, influences muscle recovery. We assessed the nutritional status and daytime pattern of protein intake in senior professional and elite youth soccer players and compared findings against published recommendations. Fourteen senior professional (SP) and 15 youth elite (YP) soccer players from the Dutch premier division completed nutritional assessments using a 24-hr web-based recall method. Recall days consisted of a match, postmatch, rest, and training day. Daily energy intake over the 4-day period was similar between SP (2988 ± 583 kcal/day) and YP (2938 ± 465 kcal/day; p = .800). Carbohydrate intake over the combined 4-day period was lower in SP (4.7 ± 0.7 g·kg-1 BM·day-1) vs. YP (6.0 ± 1.5 g·kg-1 BM·day-1, p = .006) and SP failed to meet recommended carbohydrate intakes on match and training days. Conversely, recommended protein intakes were met for SP (1.9 ± 0.3 g·kg-1 BM·day-1) and YP (1.7 ± 0.4 g·kg-1 BM·day-1), with no differences between groups (p = .286). Accordingly, both groups met or exceeded recommended daily protein intakes on individual match, postmatch, rest and training days. A similar "balanced" daytime pattern of protein intake was observed in SP and YP. To conclude, SP increased protein intake on match and training days to a greater extent than YP, however at the expense of carbohydrate intake. The daytime distribution of protein intake for YP and SP aligned with current recommendations of a balanced protein meal pattern.

Extensive monitoring through multiple blood samples in professional soccer players.

PubMed

Heisterberg, Mette F; Fahrenkrug, Jan; Krustrup, Peter; Storskov, Anders; Kjær, Michael; Andersen, Jesper L

2013-05-01

The aim of this study was to make a comprehensive gathering of consecutive detailed blood samples from professional soccer players and to analyze different blood parameters in relation to seasonal changes in training and match exposure. Blood samples were collected 5 times during a 6-month period and analyzed for 37 variables in 27 professional soccer players from the best Danish league. Additionally, the players were tested for body composition, V[Combining Dot Above]O2max and physical performance by the Yo-Yo intermittent endurance submax test (IE2). Multiple variations in blood parameters occurred during the observation period, including a decrease in hemoglobin and an increase in hematocrit as the competitive season progressed. Iron and transferrin were stable, whereas ferritin showed a decrease at the end of the season. The immunoglobulin A (IgA) and IgM increased in the period with basal physical training and at the end of the season. Leucocytes decreased with increased physical training. Lymphocytes decreased at the end of the season. The V[Combining Dot Above]O2max decreased toward the end of the season, whereas no significant changes were observed in the IE2 test. The regular blood samples from elite soccer players reveal significant changes that may be related to changes in training pattern, match exposure, or length of the match season. Especially the end of the preparation season and at the end of the competitive season seem to be time points were the blood-derived values indicate that the players are under excessive physical strain and might be more subjected to a possible overreaching-overtraining conditions. We suggest that regular analyses of blood samples could be an important initiative to optimize training adaptation, training load, and game participation, but sampling has to be regular, and a database has to be built for each individual player.

Retention of movement pattern changes after a lower extremity injury prevention program is affected by program duration.

PubMed

Padua, Darin A; DiStefano, Lindsay J; Marshall, Stephen W; Beutler, Anthony I; de la Motte, Sarah J; DiStefano, Michael J

2012-02-01

Changes in movement patterns have been repeatedly observed immediately after completing a lower extremity injury prevention program. However, it is not known if movement pattern changes are maintained after discontinuing the training program. The ability to maintain movement pattern changes after training has ceased may be influenced by the program's duration. The authors hypothesized that among individuals who completed either a 3-month or 9-month training program and who demonstrated immediate movement pattern changes, only those who completed the 9-month training program would maintain movement pattern changes after a 3-month period of no longer performing the exercises. Cohort study; Level of evidence, 2. A total of 140 youth soccer athletes from 15 separate teams volunteered to participate. Athletes' movement patterns were assessed using the Landing Error Scoring System (LESS) at pretest, posttest, and 3 months after ceasing the program (retention test). Eighty-four of the original 140 participants demonstrated improvements in their LESS scores between pretest and posttest (change in LESS score >0) and were included in the final analyses for this study (n = 84; 20 boys and 64 girls; mean age, 14 ± 2 years; age range, 11-17 years). Teams performed 3-month (short-duration group) and 9-month (extended-duration group) injury prevention programs. The exercises performed were identical for both groups. Teams performed the programs as part of their normal warm-up routine. Although both groups improved their total LESS scores from pretest to posttest, only the extended-duration training group retained their improvements 3 months after ceasing the injury prevention program (F(2,137) = 3.38; P = .04). Results suggest that training duration may be an important factor to consider when designing injury prevention programs that facilitate long-term changes in movement control.

Professional soccer is associated with radiographic cam and pincer hip morphology.

PubMed

Falotico, Guilherme Guadagnini; Arliani, Gustavo Gonçalves; Yamada, André Fukunishi; Fernandes, Artur da Rocha Correa; Ejnisman, Benno; Cohen, Moises

2018-06-06

Femoroacetabular impingement (FAI) syndrome is characterized by a triad: symptoms, clinical signs and imaging findings. Some individuals, especially athletes, have only imaging alterations. The objective of this study was to evaluate the prevalence of cam and pincer morphology in professional soccer players compared with a control group of non-athletes and to investigate the association between the age at which players start playing competitive soccer more than three times per week and duration of the soccer career with the prevalence of these radiographic findings. The prevalence of cam and pincer morphology in sixty professional adult male soccer players and thirty-two male controls was determined using pelvic anteroposterior radiography. Data were recorded for all hips and correlated with the age at which the players started competitive soccer practice and with the duration of their soccer career. The prevalence of morphological FAI in the soccer players was 92.5% versus 28.1% in the controls (p < 0.001). The duration of the soccer career was positively correlated with the alpha angle (p = 0.033) and negatively correlated with the retroversion index (p = 0.009). The age at which competitive play began was inversely correlated with the alpha angle (p < 0.001). The study showed a high prevalence of cam and pincer morphology in Brazilian professional soccer players compared with controls. The duration of the soccer career was associated with an increased alpha angle and a decreased retroversion index, and the age at which competitive soccer participation began was negatively associated with alpha angle values. Finally, this manuscript provides data about the association between greater exposure to soccer and cam and pincer morphological changes in the hip; specifically, cam morphology was more common in patients who began participating in sports at earlier ages. This information serves as an alert for coaches of youth teams to manage the training load in youth athletes. III.

Wellbeing perception and the impact on external training output among elite soccer players.

PubMed

Malone, Shane; Owen, Adam; Newton, Matt; Mendes, Bruno; Tiernan, Leo; Hughes, Brian; Collins, Kieran

2018-01-01

The objective of the investigation was to observe the impact of player wellbeing on the training output of elite soccer players. Prospective cohort design. Forty-eight soccer players (age: 25.3±3.1years; height: 183±7cm; mass: 72±7kg) were involved in this single season observational study across two teams. Each morning, pre-training, players completed customised perceived wellbeing questionnaires. Global positioning technology devices were used to measure external load (total distance, total high-speed running distance, high speed running, player load, player load slow, maximal velocity, maximal velocity exposures). Players reported ratings of perceived exertion using the modified Borg CR-10 scale. Integrated training load ratios were also analysed for total distance:RPE, total high speed distance:RPE player load:RPE and player load slow:RPE respectively. Mixed-effect linear models revealed significant effects of wellbeing Z-score on external and integrated training load measures. A wellbeing Z-score of -1 corresponded to a -18±2m (-3.5±1.1%), 4±1m (-4.9±2.1%,) 0.9±0.1kmh -1 (-3.1±2.1%), 1±1 (-4.6±2.9%), 25±3AU (-4.9±3.1%) and 11±0.5AU (-8.9±2.9%) reduction in total high speed distance, high speed distance, maximal velocity, maximal velocity exposures, player load and player load slow respectively. A reduction in wellbeing impacted external:internal training load ratios and resulted in -0.49±0.12mmin -1 , -1.20±0.08mmin -1 ,-0.02±0.01AUmin -1 in total distance:RPE, total high speed distance:RPE and player load slow:RPE respectively. The results suggest that systematic monitoring of player wellbeing within soccer cohorts can provide coaches with information about the training output that can be expected from individual players during a training session. Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

The effect of concurrent training organisation in youth elite soccer players.

PubMed

Enright, Kevin; Morton, James; Iga, John; Drust, Barry

2015-11-01

This study compared the adaptive responses to two concurrent training programmes frequently used in professional soccer. Fifteen youth soccer players (17.3 ± 1.6 years, 1.82 ± 0.06 m, 77.0 ± 7.3 kg; VO2 peak, 62.0 ± 4.7 ml(-1) kg(-1) min(-1)) who compete in the English Premier League volunteered for this study. In addition to completing their habitual training practices, the participants were asked to alter the organisation concurrent training by performing strength (S) training either prior to (S + E, n = 8) or after (E + S, n = 7) soccer-specific endurance training (E) 2d wk(-1) for 5 wk(-1). With the exception of 30 m sprint, IMVC PF, quadriceps strength (60°/s(CON), 180°/s(CON), 120°/s(ECC)) pooled data revealed training effects across all other performances measures (P < 0.05). Whilst ANCOVA indicated no significant interaction effects for training condition, the difference between the means divided by the pooled standard deviation demonstrated large effect sizes in the E + S condition for in HBS 1-RM [S + E vs E + S; -0.54 (9.6 %) vs -1.79 (19.6 %)], AoP-M [-0.72 (7.9 %) vs -1.76 (14.4 %)], SJ [-0.56, (4.4 %), vs -1.08, (8.1 %)], IMVC-LR; [-0.50, (20.3 %) vs -1.05 (27.3 %)], isokinetic hamstring strength 60°/s (CON) [-0.64, (12.2 %) vs -0.95 (19.2 %)], 120°/s(ECC) [-0.78 (27.9 %) vs -1.55 (23.3 %)] and isokinetic quadriceps strength 180°/s (CON) [-0.23 (2.5 %) vs -1.52 (13.2 %)]. Results suggest the organisation of concurrent training, recovery time allocated between training bouts and the availability nutrition may be able to modulate small but clinically significant changes in physical performance parameters associated with match-play. This may have practical implications for practitioners who prescribe same day concurrent training protocols.

The Physical and Athletic Performance Characteristics of Division I Collegiate Female Soccer Players by Position.

PubMed

Lockie, Robert G; Moreno, Matthew R; Lazar, Adrina; Orjalo, Ashley J; Giuliano, Dominic V; Risso, Fabrice G; Davis, DeShaun L; Crelling, Jeff B; Lockwood, John R; Jalilvand, Farzad

2018-02-01

Lockie, RG, Moreno, MR, Lazar, A, Orjalo, AJ, Giuliano, DV, Risso, FG, Davis, DL, Crelling, JB, Lockwood, JR, and Jalilvand, F. The physical and athletic performance characteristics of Division I collegiate female soccer players by position. J Strength Cond Res 32(2): 334-343, 2018-Playing positions in soccer can exhibit different movement demands during a match, contributing to variations in physical and performance characteristics. National Collegiate Athletic Association (NCAA) soccer features different substitution rules when compared to FIFA-sanctioned matches, which could influence each players' characteristics. Therefore, this study determined the athletic performance characteristics of Division I female soccer players. Twenty-six players (3 goalkeepers; 8 defenders; 10 midfielders; 5 forwards) from the same squad completed assessments of: lower-body power (vertical and standing broad jump); linear (0-5, 0-10, 0-30 meter [m] sprint intervals) and change-of-direction (pro-agility shuttle; arrowhead change-of-direction speed test) speed; and soccer-specific fitness (Yo-Yo Intermittent Recovery Test [YYIRT] levels 1 and 2). Players were split into position groups, and a Kruskal-Wallis H test with post hoc pairwise analyses (p ≤ 0.05) calculated significant between-group differences. There were no differences in age, height, or body mass between the positions. Midfielders had a faster 0-5 m time compared with the defenders (p = 0.017) and the goalkeepers (p = 0.030). The defenders (p = 0.011) and midfielders (p = 0.013) covered a greater YYIRT2 distance compared with the goalkeepers. There were no other significant between-position differences. Overall, Division I collegiate female players from the same squad demonstrated similar characteristics as measured by soccer-specific performance tests, which could allow for flexibility in position assignments. However, a relatively homogenous squad could also indicate commonality in training prescription, particularly regarding acceleration and high-intensity running. Strength and conditioning coaches may have to consider the specific movement demands of individual positions when training these capacities.

Fatigue Responses in Various Muscle Groups in Well-Trained Competitive Male Players after a Simulated Soccer Game

PubMed Central

Fransson, Dan; Vigh-Larsen, Jeppe Foged; Fatouros, Ioannis G.; Krustrup, Peter; Mohr, Magni

2018-01-01

Abstract We examined the degree of post-game fatigue and the recovery pattern in various leg and upper-body muscle groups after a simulated soccer game. Well-trained competitive male soccer players (n = 12) participated in the study. The players completed the Copenhagen Soccer Test, a 2 x 45 min simulated soccer protocol, following baseline measures of maximal voluntary contractions of multiple muscle groups and systemic markers of muscle damage and inflammation at 0, 24 and 48 h into recovery. All muscle groups had a strength decrement (p ≤ 0.05) at 0 h post-match with knee flexors (14 ± 3%) and hip abductors (6 ± 1%) demonstrating the largest and smallest impairment. However, 24 h into recovery all individual muscles had recovered. When pooled in specific muscle groups, the trunk muscles and knee joint muscles presented the largest decline 0 h post-match, 11 ± 2% for both, with the performance decrement still persistent (4 ± 1%, p ≤ 0.05) for trunk muscles 24 h into recovery. Large inter-player variations were observed in game-induced fatigue and recovery patterns in the various muscle groups. Markers of muscle damage and inflammation peaked 0 h post-match (myoglobin) and 24 h into recovery (creatine kinase), respectively, but thereafter returned to baseline. Intermittent test performance correlated with creatine kinase activity 24 h after the Copenhagen Soccer Test (r = -0.70; p = 0.02). In conclusion, post-game fatigue is evident in multiple muscle groups with knee flexors showing the greatest performance decrement. Fatigue and recovery patterns vary markedly between muscle groups and players, yet trunk muscles display the slowest recovery. PMID:29599862

Anthropometric and Somatotype Characteristics of Young Soccer Players: Differences Among Categories, Subcategories, and Playing Position.

PubMed

Perroni, Fabrizio; Vetrano, Mario; Camolese, Giancarlo; Guidetti, Laura; Baldari, Carlo

2015-08-01

Considering that anthropometric parameters are important factors in the performance of the soccer players, the aim of this study was to explore the differences in anthropometric and somatotype characteristics of Italian young soccer players. Weight, height, body mass index, and somatotype of 112 young soccer players, grouped in Giovanissimi "A" (14 years), "B" (13 years), and "C" (12 years) as well as Allievi "B" (15 years) and "A" (16 years) and "Juniores" (older than 17 years), were evaluated. Statistical analysis tests were computed at p ≤ 0.05, and an analysis of variance for each somatotype was calculated to analyze the main effects and interactions of the factors: categories, subcategories, and playing position. Bonferroni's post hoc analysis was used to identify differences among mean values. Considering all subjects, we have found significant differences in categories, subcategories, and playing position between anthropometric values and a somatotype value of 2.8-3.8-2.9. Significant differences have found among goalkeepers and the others playing position in endomorphy (p ≤ 0.001) and with defenders and midfielders in ectomorphy (p < 0.01) components, whereas no differences in mesomorphy. Analyzing the interaction between subcategories and playing position factors, a significant effect was found only in the endomorphy component (p = 0.05). The analysis of anthropometric characteristic of Italian young soccer players indicates that players have high muscularity value and low adiposity. This study showed the presence of somatotype differences for playing position within categories also in the youngest categories and subcategories, in particular, in the endomorphy component. Young soccer players should be trained with more appropriate and specific training load to avoid the increased injury risk during adolescence.

Effects of age on the soccer-specific cognitive-motor performance of elite young soccer players: Comparison between objective measurements and coaches’ evaluation

PubMed Central

Chauvin, Alan; Chassot, Steve; Chenevière, Xavier; Taube, Wolfgang

2017-01-01

The cognitive-motor performance (CMP), defined here as the capacity to rapidly use sensory information and transfer it into efficient motor output, represents a major contributor to performance in almost all sports, including soccer. Here, we used a high-technology system (COGNIFOOT) which combines a visual environment simulator fully synchronized with a motion capture system. This system allowed us to measure objective real-time CMP parameters (passing accuracy/speed and response times) in a large turf-artificial grass playfield. Forty-six (46) young elite soccer players (including 2 female players) aged between 11 and 16 years who belonged to the same youth soccer academy were tested. Each player had to pass the ball as fast and as accurately as possible towards visual targets projected onto a large screen located 5.32 meters in front of him (a short pass situation). We observed a linear age-related increase in the CMP: the passing accuracy, speed and reactiveness of players improved by 4 centimeters, 2.3 km/h and 30 milliseconds per year of age, respectively. These data were converted into 5 point-scales and compared to the judgement of expert coaches, who also used a 5 point-scale to evaluate the same CMP parameters but based on their experience with the players during games and training. The objectively-measured age-related CMP changes were also observed in expert coaches’ judgments although these were more variable across coaches and age categories. This demonstrates that high-technology systems like COGNIFOOT can be used in complement to traditional approaches of talent identification and to objectively monitor the progress of soccer players throughout a cognitive-motor training cycle. PMID:28953958

Effects of age on the soccer-specific cognitive-motor performance of elite young soccer players: Comparison between objective measurements and coaches' evaluation.

PubMed

Hicheur, Halim; Chauvin, Alan; Chassot, Steve; Chenevière, Xavier; Taube, Wolfgang

2017-01-01

The cognitive-motor performance (CMP), defined here as the capacity to rapidly use sensory information and transfer it into efficient motor output, represents a major contributor to performance in almost all sports, including soccer. Here, we used a high-technology system (COGNIFOOT) which combines a visual environment simulator fully synchronized with a motion capture system. This system allowed us to measure objective real-time CMP parameters (passing accuracy/speed and response times) in a large turf-artificial grass playfield. Forty-six (46) young elite soccer players (including 2 female players) aged between 11 and 16 years who belonged to the same youth soccer academy were tested. Each player had to pass the ball as fast and as accurately as possible towards visual targets projected onto a large screen located 5.32 meters in front of him (a short pass situation). We observed a linear age-related increase in the CMP: the passing accuracy, speed and reactiveness of players improved by 4 centimeters, 2.3 km/h and 30 milliseconds per year of age, respectively. These data were converted into 5 point-scales and compared to the judgement of expert coaches, who also used a 5 point-scale to evaluate the same CMP parameters but based on their experience with the players during games and training. The objectively-measured age-related CMP changes were also observed in expert coaches' judgments although these were more variable across coaches and age categories. This demonstrates that high-technology systems like COGNIFOOT can be used in complement to traditional approaches of talent identification and to objectively monitor the progress of soccer players throughout a cognitive-motor training cycle.

Fatigue Responses in Various Muscle Groups in Well-Trained Competitive Male Players after a Simulated Soccer Game.

PubMed

Fransson, Dan; Vigh-Larsen, Jeppe Foged; Fatouros, Ioannis G; Krustrup, Peter; Mohr, Magni

2018-03-01

We examined the degree of post-game fatigue and the recovery pattern in various leg and upper-body muscle groups after a simulated soccer game. Well-trained competitive male soccer players (n = 12) participated in the study. The players completed the Copenhagen Soccer Test, a 2 x 45 min simulated soccer protocol, following baseline measures of maximal voluntary contractions of multiple muscle groups and systemic markers of muscle damage and inflammation at 0, 24 and 48 h into recovery. All muscle groups had a strength decrement ( p ≤ 0.05) at 0 h post-match with knee flexors (14 ± 3%) and hip abductors (6 ± 1%) demonstrating the largest and smallest impairment. However, 24 h into recovery all individual muscles had recovered. When pooled in specific muscle groups, the trunk muscles and knee joint muscles presented the largest decline 0 h post-match, 11 ± 2% for both, with the performance decrement still persistent (4 ± 1%, p ≤ 0.05) for trunk muscles 24 h into recovery. Large inter-player variations were observed in game-induced fatigue and recovery patterns in the various muscle groups. Markers of muscle damage and inflammation peaked 0 h post-match (myoglobin) and 24 h into recovery (creatine kinase), respectively, but thereafter returned to baseline. Intermittent test performance correlated with creatine kinase activity 24 h after the Copenhagen Soccer Test (r = -0.70; p = 0.02). In conclusion, post-game fatigue is evident in multiple muscle groups with knee flexors showing the greatest performance decrement. Fatigue and recovery patterns vary markedly between muscle groups and players, yet trunk muscles display the slowest recovery.

Linking at-risk South African girls to sexual violence and reproductive health services: A mixed-methods assessment of a soccer-based HIV prevention program and pilot SMS campaign.

PubMed

Merrill, Katherine G; Merrill, Jamison C; Hershow, Rebecca B; Barkley, Chris; Rakosa, Boitumelo; DeCelles, Jeff; Harrison, Abigail

2018-04-30

Grassroot Soccer developed SKILLZ Street-a soccer-based life skills program with a supplementary SMS platform-to support adolescent girls at risk for HIV, violence, and sexual and reproductive health challenges. We conducted a mixed-methods assessment of preliminary outcomes and implementation processes in three primary schools in Soweto, South Africa, from August to December 2013. Quantitative methods included participant attendance and SMS platform usage tracking, pre/post questionnaires, and structured observation. Qualitative data were collected from program participants, parents, teachers, and a social worker during 6 focus group discussions and 4 in-depth interviews. Of 394 participants enrolled, 97% (n = 382) graduated, and 217 unique users accessed the SMS platform. Questionnaires completed by 213 participants (mean age: 11.9, SD: 3.02 years) alongside qualitative findings showed modest improvements in participants' perceptions of power in relationships and gender equity, self-esteem, self-efficacy to avoid unwanted sex, communication with others about HIV and sex, and HIV-related knowledge and stigma. The coach-participant relationship, safe space, and integration of soccer were raised as key intervention components. Implementation challenges were faced around delivery of soccer-based activities. Findings highlight the relevance and importance of programs like SKILLZ Street in addressing challenges facing adolescent girls in South African townships. Recommendations for future programs are provided. Copyright © 2018 Elsevier Ltd. All rights reserved.

Detection of goal events in soccer videos

NASA Astrophysics Data System (ADS)

Kim, Hyoung-Gook; Roeber, Steffen; Samour, Amjad; Sikora, Thomas

2005-01-01

In this paper, we present an automatic extraction of goal events in soccer videos by using audio track features alone without relying on expensive-to-compute video track features. The extracted goal events can be used for high-level indexing and selective browsing of soccer videos. The detection of soccer video highlights using audio contents comprises three steps: 1) extraction of audio features from a video sequence, 2) event candidate detection of highlight events based on the information provided by the feature extraction Methods and the Hidden Markov Model (HMM), 3) goal event selection to finally determine the video intervals to be included in the summary. For this purpose we compared the performance of the well known Mel-scale Frequency Cepstral Coefficients (MFCC) feature extraction method vs. MPEG-7 Audio Spectrum Projection feature (ASP) extraction method based on three different decomposition methods namely Principal Component Analysis( PCA), Independent Component Analysis (ICA) and Non-Negative Matrix Factorization (NMF). To evaluate our system we collected five soccer game videos from various sources. In total we have seven hours of soccer games consisting of eight gigabytes of data. One of five soccer games is used as the training data (e.g., announcers' excited speech, audience ambient speech noise, audience clapping, environmental sounds). Our goal event detection results are encouraging.

Comparison between two types of anaerobic speed endurance training in competitive soccer players.

PubMed

Mohr, Magni; Krustrup, Peter

2016-06-01

The purpose of the present study was to examine the effects of additional in-season speed endurance production versus speed endurance maintenance training regimes on performance in competitive male soccer players. In a randomised controlled trial 18 male sub-elite players were exposed to additional speed endurance production (SEP) or speed endurance maintenance (SEM) training (two additional sessions/wk for 4 weeks) during the competitive season. Players performed the Yo-Yo intermittent recovery level 2 test (YYIR2) and a repeated sprint test (RST) pre- and post-intervention. Yo-Yo IR2 performance increased (p<0.001) by 50 ± 8% and 26 ± 5% in SEP and SEM, respectively, with greater (p=0.03) improvement in SEP. RST performance improved by 2.1 ± 0.3% and 1.3 ± 0.4% in SEP and SEM, respectively, while the RST fatigue index decreased (4.4 ± 0.8 to 3.4 ± 0.5%; p<0.04) in SEP only. Peak and average speed during training were higher (p<0.001) in SEP than in SEM (24.5 ± 0.3 vs 19.2 ± 0.3 and 15.5 ± 0.1 km·h-1 vs 9.4 ± 0.1 km·h-1). Additional in-season anaerobic speed endurance production and maintenance training improves high-intensity exercise performance in competitive soccer players with superior effects of speed endurance production training.

Influence of fatigue, stress, muscle soreness and sleep on perceived exertion during submaximal effort.

PubMed

Haddad, Monoem; Chaouachi, Anis; Wong, Del P; Castagna, Carlo; Hambli, Mourad; Hue, Olivier; Chamari, Karim

2013-07-02

The aim of this study was to assess the effects of the Hooper's Index variations (i.e., self-ratings of fatigue, stress, delayed onset muscle soreness (DOMS), and sleep) on rating of perceived exertion during a 10 min submaximal exercise training session (RPE-10 min) and then check the stability and the internal consistency of RPE-10 min. Seventeen junior soccer players took part in this study. The individual Hooper's indices taken before each training session were correlated with RPE-10 min during a constant intensity and duration effort (10 min) using Pearson product moment correlation. Intraclass correlation (ICC) was used to assess the internal consistency of the RPE-10 min. All individual correlations between RPE-10 min and quality of sleep and quantity of fatigue, stress, and DOMS were non-significant (p>0.05). No significant correlations were resulted between RPE-10 min and Hooper's Index in all athletes. The ICC of RPE-10 min was 0.77 thus demonstrating internal consistency. The results of the present study demonstrated the objectivity and utility of RPE as a psychological tool for monitoring training during traditional soccer training. Therefore, the results of the present study suggest that fatigue, stress, DOMS and sleep are not major contributors of perceived exertion during traditional soccer training without excessive training loads. It seems that psychobiological factors other than fatigue, stress, DOMS and sleep may have mediated the 10 min exercise perceptual intensity. © 2013.

Time course of oxidative stress, inflammation and muscle damage markers for five days after a soccer match: effects of sex and playing position.

PubMed

Souglis, Athanasios; Bogdanis, Gregory C; Chryssanthopoulos, Costas; Apostolidis, Nikolaos; Geladas, Nikos D

2018-01-03

This study examined the influence of sex and playing position on the time-course of selected oxidative stress, inflammation and muscle damage markers following an official soccer match. Sixty professional soccer players (30 male and 30 female) were divided into three groups, according to their playing position: defenders, midfielders and attackers. Each group consisted of 10 male and 10 female players. Sixty healthy volunteers (30 males and 30 females) served as control. Blood samples were taken before and after the match and daily for five days after the match. Analysis of variance revealed different responses over time between sex and playing positions, as shown by the 3-way interaction, for creatine kinase (CK), protein carbonyls (PC), catalase, fibrinogen (FIB), uric acid (UA), lactate dehydrogenase (LDH), reduced glutathione, C-reactive protein and interleukin-6 (IL-6) (p < 0.01).Male players had higher values compared with females of the same playing position, for all oxidative, inflammatory and muscle damage indices (p<0.01). Also, in both sexes, midfielders had higher peaks in all indices compared with defenders (p < 0.05). Five days after the game CK and UA concentrations had not returned to pre-game levels in any exercise group, whereas PC were still elevated in male midfielders and attackers (p < 0.05).These results show that sex and playing position influence the time-course of selected oxidative stress, inflammation and muscle damage markers following an official soccer game. This information should be taken into account by practitioners for the design of training programs following match play.

Injury profile of a professional soccer team in the premier league of iran.

PubMed

Hassabi, Mohammad; Mohammad-Javad Mortazavi, Seyed; Giti, Mohammad-Reza; Hassabi, Majid; Mansournia, Mohammad-Ali; Shapouran, Sara

2010-12-01

Despite numerous studies which have been done regarding soccer injuries worldwide, there is lack of available data considering the epidemiology of injuries in the Iranian soccer premier league, although it is the most popular sport in the country. The main goal of this research was to determine the incidence of physical injuries in the studied population, considering other characteristics such as site, type and mechanism as well. Twenty one adult male professional soccer players (age 24±3), members of a team (Tehran-Pas) participating in Iranian premier league, were followed during a 4-month period. The injury characteristics and exposure times were recorded by the team physician during all the matches and training sessions. The total exposure time was 2610 playing hours (2352 h of training versus 258 h of competition). Eighty six percent of the injuries were acute. Incidence of acute injuries was 16.5 (95% CI: 12-22) per 1000 hours of playing (11.5 per 1000 hrs of training and 62 per 1000 hrs of competition). The most common types of injuries were strains followed by contusions, each of which constituted 30% of acute injuries. More than 80% of injuries occurred in lower limbs, especially in thigh and groin regions. Nearly 60% of acute injuries occurred in dominant side of the body, and collision was the reason of about half of the acute injuries. Severity of more than 70% of the injuries was minor. On average each injury had led the player being off the field for about 10 days. The incidence of injury in this research is in range of numbers obtained in important international tournaments but the rate of injuries during training sessions is higher than comparable studies.

The Effect of Plyometric Training Volume on Athletic Performance in Prepubertal Male Soccer Players.

PubMed

Chaabene, Helmi; Negra, Yassine

2017-10-01

To assess and compare the effects of 8 wk of in-season (2 sessions/wk) low- and high-volume plyometric training (PT) on measures of physical fitness in prepubertal male soccer players. A total of 25 soccer players were randomly assigned to a low-volume PT group (LPT; n = 13, age 12.68 ± 0.23 y, age at peak height velocity [APHV] 14.25 ± 0.29 y, maturity offset -1.57 ± 0.29 y) or a high-volume PT group (HPT; n = 12, age 12.72 ± 0.27 y, APHV 14.33 ± 0.77 y, maturity offset -1.61 ± 0.76 y). A linear-sprint test (5-m, 10-m, 20-m, and 30-m), change-of-direction (CoD) test, and vertical- (squat-jump [SJ]), countermovement- (CMJ), and horizontal-jump (standing long jump [SLJ]) test were carried out before and after 8 wk of PT. There was a significant main effect of time for sprint outcomes (5-m, P = .005, ES = 0.86; 10-m, P = .006, ES = 0.85; 20-m, P = .03, ES = 0.64, and 30-m, P = .05, ES = 0.57), CoD (P = .002, ES = 0.96), SJ (P = .008, ES = 0.81; CMJ, P = .01, ES = 0.73), and SLJ ability (P = .007, ES = 0.83). There were no significant training group × time interactions in any measured outcomes. After 8 wk of training, results showed similar performance improvement on measures of sprint time, CoD, and jumping ability between LPT and HPT groups. From a time-efficiency perspective, it is recommended to use LPT in prepubertal male soccer players to improve their proxies of athletic performance.

Injury Prevention Exercise Programs for Professional Soccer: Understanding the Perceptions of the End-Users.

PubMed

OʼBrien, James; Finch, Caroline F

2017-01-01

To evaluate the perceptions of professional soccer players and staff members toward injury prevention exercise programs (IPEPs). Self-report survey. Four professional soccer teams in 4 different countries. 126 players, coaches, physiotherapists, and fitness coaches were invited to participate, with 72 respondents. Web-based survey detailing perceptions of lower limb (LL) injury susceptibility and seriousness, the value of IPEPs in general, and more specifically the International Federation of Association Football (FIFA) 11+. The vast majority of the respondents believed that professional soccer players are at high risk of LL injuries (93%) and that players should perform evidence-based injury prevention exercises (98%). They also agreed that LL injuries can shorten a player's career (85%), cause physical problems later in life (82%), and negatively impact on team performance (77%). However, perceptions varied across teams regarding which types of injury prevention exercises are effective, who holds responsibility for injury prevention, and when IPEPs should be performed. Specific knowledge of the FIFA 11+ was very low and 47% of respondents believed the program would need modification for use in their team. Players and staff members in professional soccer teams strongly support the use of evidence-based IPEPs. However, perceptions vary considerably between teams regarding which exercises can prevent injuries, who holds the responsibility for injury prevention, and when preventive exercises should be performed. Enhancing the ultimate impact of IPEPs in professional soccer requires a detailed understanding of each team's specific implementation context.

Soccer increases bone mass in prepubescent boys during growth: a 3-yr longitudinal study.

PubMed

Zouch, Mohamed; Zribi, Anis; Alexandre, Christian; Chaari, Hamada; Frere, Delphine; Tabka, Zouhair; Vico, Laurence

2015-01-01

The aim of this study was to examine the effect of 3-yr soccer practice on bone acquisition in prepubescent boys. We investigated 65 boys (aged 10-13 yr, Tanner stage I) at baseline, among which only 40 boys (Tanner stages II and III) have continued the 3-yr follow-up: 23 soccer players (F) completed 2-5 h of training plus 1 competition game per week and 17 controls (C). Bone mineral density (BMD, g/cm(2)) and bone mineral content (BMC, g) were measured by dual-energy X-ray absorptiometry at different sites. At baseline, BMD was higher in soccer players than in controls in the whole body and legs. In contrast, there was nonsignificant difference BMD in head, femoral neck, arms, and BMC in all measured sites between groups. At 3-yr follow-up, soccer players were found to have higher BMD and BMC at all sites than controls, except for head BMD and BMC and arms BMC in which the difference was nonsignificant between groups. During the 3-yr follow-up, the soccer players were found to gain significantly more in lumbar spine (31.2% ± 2.9% vs 23.9% ± 2.1%; p < 0.05), femoral neck (24.1% ± 1.8% vs 11.4% ± 1.9%; p < 0.001), whole body (16.5% ± 1.4% vs 11.8% ± 1.5%; p < 0.05), and nondominant arm BMD (18.2% ± 1.4% vs 13.6% ± 1.7%; p < 0.05) as well as lumbar spine (62.5% ± 20.1% vs 39.5% ± 20.1%; p < 0.001), femoral neck, (37.7% ± 14.2% vs 28.9% ± 12.8%; p < 0.05) and nondominant arm BMC (68.6% ± 22.9% vs 50.1% ± 22.4%; p < 0.05) than controls. In contrast, soccer players have less %BMD and %BMC changes in the head than controls. A nonsignificant difference was found in legs, dominant arm, head %BMD and %BMC changes, and whole-body %BMC changes between groups. In summary, we suggest that soccer has an osteogenic effect BMD and BMC in loaded sites in pubertal soccer players. The increased bone mass induced by soccer training in the stressed sites was associated to a decreased skull bone mass after 3 yr of follow-up. Copyright © 2015 The International Society for Clinical Densitometry. Published by Elsevier Inc. All rights reserved.

Improving Sprint Performance in Soccer: Effectiveness of Jump Squat and Olympic Push Press Exercises

PubMed Central

Loturco, Irineu; Pereira, Lucas Adriano; Kobal, Ronaldo; Maldonado, Thiago; Piazzi, Alessandro Fromer; Bottino, Altamiro; Kitamura, Katia; Cal Abad, Cesar Cavinato; de Arruda, Miguel; Nakamura, Fabio Yuzo

2016-01-01

Training at the optimum power load (OPL) is an effective way to improve neuromuscular abilities of highly trained athletes. The purpose of this study was to test the effects of training using the jump squat (JS) or Olympic push-press (OPP) exercises at the OPL during a short-term preseason on speed-power related abilities in high-level under-20 soccer players. The players were divided into two training groups: JS group (JSG) and OPP group (OPPG). Both groups undertook 12 power-oriented sessions, using solely JS or OPP exercises. Pre- and post-6 weeks of training, athletes performed squat jump (SJ), countermovement jump (CMJ), sprinting speed (5, 10, 20 and 30 m), change of direction (COD) and speed tests. To calculate the transfer effect coefficient (TEC) between JS and MPP OPP and the speed in 5, 10, 20, and 30 m, the ratio between the result gain (effect size [ES]) in the untrained exercise and result gain in the trained exercise was calculated. Magnitude based inference and ES were used to test the meaningful effects. The TEC between JS and VEL 5, 10, 20, and 30 m ranged from 0.77 to 1.29, while the only TEC which could be calculated between OPP and VEL 5 was rather low (0.2). In addition, the training effects of JS on jumping and speed related abilities were superior (ES ranging from small to large) to those caused by OPP (trivial ES). To conclude, the JS exercise is superior to the OPP for improving speed-power abilities in elite young soccer players. PMID:27100085

Improving Sprint Performance in Soccer: Effectiveness of Jump Squat and Olympic Push Press Exercises.

PubMed

Loturco, Irineu; Pereira, Lucas Adriano; Kobal, Ronaldo; Maldonado, Thiago; Piazzi, Alessandro Fromer; Bottino, Altamiro; Kitamura, Katia; Cal Abad, Cesar Cavinato; de Arruda, Miguel; Nakamura, Fabio Yuzo

2016-01-01

Training at the optimum power load (OPL) is an effective way to improve neuromuscular abilities of highly trained athletes. The purpose of this study was to test the effects of training using the jump squat (JS) or Olympic push-press (OPP) exercises at the OPL during a short-term preseason on speed-power related abilities in high-level under-20 soccer players. The players were divided into two training groups: JS group (JSG) and OPP group (OPPG). Both groups undertook 12 power-oriented sessions, using solely JS or OPP exercises. Pre- and post-6 weeks of training, athletes performed squat jump (SJ), countermovement jump (CMJ), sprinting speed (5, 10, 20 and 30 m), change of direction (COD) and speed tests. To calculate the transfer effect coefficient (TEC) between JS and MPP OPP and the speed in 5, 10, 20, and 30 m, the ratio between the result gain (effect size [ES]) in the untrained exercise and result gain in the trained exercise was calculated. Magnitude based inference and ES were used to test the meaningful effects. The TEC between JS and VEL 5, 10, 20, and 30 m ranged from 0.77 to 1.29, while the only TEC which could be calculated between OPP and VEL 5 was rather low (0.2). In addition, the training effects of JS on jumping and speed related abilities were superior (ES ranging from small to large) to those caused by OPP (trivial ES). To conclude, the JS exercise is superior to the OPP for improving speed-power abilities in elite young soccer players.

Executive Functioning in Highly Talented Soccer Players

PubMed Central

Verburgh, Lot; Scherder, Erik J. A.; van Lange, Paul A.M.; Oosterlaan, Jaap

2014-01-01

Executive functions might be important for successful performance in sports, particularly in team sports requiring quick anticipation and adaptation to continuously changing situations in the field. The executive functions motor inhibition, attention and visuospatial working memory were examined in highly talented soccer players. Eighty-four highly talented youth soccer players (mean age 11.9), and forty-two age-matched amateur soccer players (mean age 11.8) in the age range 8 to 16 years performed a Stop Signal task (motor inhibition), the Attention Network Test (alerting, orienting, and executive attention) and a visuospatial working memory task. The highly talented soccer players followed the talent development program of the youth academy of a professional soccer club and played at the highest national soccer competition for their age. The amateur soccer players played at a regular soccer club in the same geographical region as the highly talented soccer players and play in a regular regional soccer competition. Group differences were tested using analyses of variance. The highly talented group showed superior motor inhibition as measured by stop signal reaction time (SSRT) on the Stop Signal task and a larger alerting effect on the Attention Network Test, indicating an enhanced ability to attain and maintain an alert state. No group differences were found for orienting and executive attention and visuospatial working memory. A logistic regression model with group (highly talented or amateur) as dependent variable and executive function measures that significantly distinguished between groups as predictors showed that these measures differentiated highly talented soccer players from amateur soccer players with 89% accuracy. Highly talented youth soccer players outperform youth amateur players on suppressing ongoing motor responses and on the ability to attain and maintain an alert state; both may be essential for success in soccer. PMID:24632735

Biology and medicine of soccer: an update.

PubMed

Shephard, R J

1999-10-01

Recent literature on the biology and medicine of soccer (primarily since 1990) has been accumulated by a combination of computer searching of relevant databases and review of the author's extensive files. From a total of 9681 papers, 540 were selected for closer scrutiny and 370 are discussed in the present review. These articles cover patterns of play and the resulting energy demands, the nutritional requirements of soccer, the anthropometric, physiological, biochemical and immunological characteristics of successful players, the influence of environmental stressors (heat, cold, hypoxia and time zone shifts), special features of female and junior competitors, selected issues in training, and the incidence and prevention of injuries. The information presented has important implications for the safety and success of soccer players; the challenge is now to ensure that this information is understood and acted upon by coaches and individual team members.

Colonic transit in soccer players.

PubMed

Sesboüé, B; Arhan, P; Devroede, G; Lecointe-Besançon, I; Congard, P; Bouchoucha, M; Fabre, J

1995-04-01

To evaluate the effects of exercise on colonic function, we measured total and segmental transit times in 11 male soccer players and nine male radiology student technicians. Diet was kept constant in all subjects, who maintained their normal activities. For the soccer players, normal activities included 15 h of training and one match each week. Transit times were measured with radioopaque markers, using the multiple-ingestion, single-radiograph technique. No overall difference in large bowel transit was observed between the two groups. Right colon transit was considerably slower in the soccer players, whereas left colon and rectal transit were slightly accelerated. We conclude that an intensive sport activity only modifies regional differences in large bowel function. This may be of importance in extreme conditions, such as those experienced by marathon runners. Data should be obtained before prescribing exercise to treat constipation.

An examination of current practices and gender differences in strength and conditioning in a sample of varsity high school athletic programs.

PubMed

Reynolds, Monica L; Ransdell, Lynda B; Lucas, Shelley M; Petlichkoff, Linda M; Gao, Yong

2012-01-01

Currently, little is known about strength and conditioning programs at the high school level. Therefore, the purpose of this research was to explore current practices in strength and conditioning for varsity high school athletes in selected sports. The following were specifically examined: who administers programs for these athletes, what kinds of training activities are done, and whether the responsible party or emphasis changes depending on the gender of the athletes. Coaches of varsity soccer, basketball, softball, and baseball in 3 large Idaho school districts were asked to complete an online survey. Sixty-seven percent (32/48) of the questionnaires were completed and used for the study. The majority of coaches (84%) provided strength and conditioning opportunities for their athletes, although only 37% required participation. Strength training programs were designed and implemented primarily by either physical education teachers or head coaches. Compared with coaches of male athletes, coaches of female athletes were less likely to know the credentials of their strength coaches, and they were less likely to use certified coaches to plan and implement their strength and conditioning programs. Most programs included dynamic warm-ups and cool-downs, plyometrics, agility training, speed training, and conditioning, and most programs were conducted 3 d·wk(-1) (76%) for sessions lasting between 30 and 59 minutes (63%). Compared with their female counterparts, male athletes were more likely to have required training, participate in strength training year round, and train using more sessions per week. This study provides additional information related to the practice of strength and conditioning in a sample of high school athletic teams.

Characterization of static balance abilities in elite soccer players by playing position and age.

PubMed

Pau, Massimiliano; Ibba, Gianfranco; Leban, Bruno; Scorcu, Marco

2014-01-01

In this study, we investigated the static balance of adult and adolescent elite soccer players to understand how expertise and playing position influence postural control. Seventy-one national level players were tested using a force platform to acquire Center-of-Pressure (COP) data in uni- and bipedal stance and calculate sway area (SA), COP path length, velocity and displacements. The results show significant differences in postural sway related to age and playing position only for single-limb stance. In particular, midfielders exhibited significantly lower values of SA with respect to defenders (-48%, p = 0.001) and the under-15 players exhibited SA 42-64% higher than all the others (p = 0.001). In the light of planning training or rehabilitation programs specific for each player's role and age, sway measurements may supply useful, objective and reliable information only for the unipedal test as the bipedal standing appears not challenging enough to let differences in balance abilities emerge.

Does trampolining and anaerobic physical fitness affect sleep?

PubMed

Buchegger, J; Fritsch, R; Meier-Koll, A; Riehle, H

1991-08-01

The structure of nocturnal sleep of 16 volunteers, participating in the anaerobic sports of trampolining, dancing, and soccer, was monitored by means of polygraphic recordings. Since trampolining requires the acquisition of unfamiliar patterns of motor coordination, it can be considered as a special form of motor learning, whereas the acquisition of motor skills specific for dancing and soccer can be linked with motor patterns of normal biped locomotion. According to this view, an experimental group of 8 volunteers was formed; they participated in a training course of trampolining. In addition, a control group of 8 subjects was recruited, who engaged in one of the other two anaerobic sports. Subjects who had acquired new motor skills during a 13-wk. program in trampolining showed a statistically significant increase in REM-sleep. By contrast, the 8 subjects of the control group showed no considerable changes in REM-sleep. This suggests that efforts in acquiring new and complex motor patterns activate processes specifically involved in the generation of REM stage during nocturnal sleep.

The Effects of 52 Weeks of Soccer or Resistance Training on Body Composition and Muscle Function in +65-Year-Old Healthy Males – A Randomized Controlled Trial

PubMed Central

Andersen, Thomas Rostgaard; Schmidt, Jakob Friis; Pedersen, Mogens Theisen; Krustrup, Peter; Bangsbo, Jens

2016-01-01

The effects of 52 weeks of soccer or resistance training were investigated in untrained elderly men. The subjects aged 68.1±2.1 yrs were randomised into a soccer (SG; n = 9), a resistance (RG; n = 9) and a control group (CG; n = 8). The subjects in SG and RG, respectively, trained 1.7±0.3 and 1.8±0.3 times weekly on average during the intervention period. Muscle function and body composition were determined before and after 16 and 52 weeks of the intervention period. In SG, BMI was reduced by 1.5% and 3.0% (p<0.05) after 16 and 52 weeks, respectively, unchanged in RG and 2% higher (p<0.05) in CG after 52 weeks of the intervention period. In SG, the response to a glucose tolerance test was 16% lower (p<0.05) after 16 wks, but not after 52 wks, compared to before the intervention period, and unchanged in RG and CG. In SG, superoxide dismutase-2 expression was 59% higher (p<0.05) after 52 wks compared to before the intervention period, and unchanged in RG and CG. In RG, upper body lean mass was 3 and 2% higher (p<0.05) after 16 and 52 wks, respectively, compared to before the intervention period, and unchanged in SG and CG. In RG, Akt-2 expression increased by 28% (p<0.01) and follistatin expression decreased by 38% (p<0.05) during the 52-wk intervention period, and was unchanged in SG and CG. Thus, long-term soccer training reduces BMI and improves anti-oxidative capacity, while long-term resistance training impacts muscle protein enzyme expression and increases lean body mass in elderly men. Trial Registration ClinicalTrials.gov: NCT01530035 PMID:26886262

The Effects of 52 Weeks of Soccer or Resistance Training on Body Composition and Muscle Function in +65-Year-Old Healthy Males--A Randomized Controlled Trial.

PubMed

Andersen, Thomas Rostgaard; Schmidt, Jakob Friis; Pedersen, Mogens Theisen; Krustrup, Peter; Bangsbo, Jens

2016-01-01

The effects of 52 weeks of soccer or resistance training were investigated in untrained elderly men. The subjects aged 68.1±2.1 yrs were randomised into a soccer (SG; n = 9), a resistance (RG; n = 9) and a control group (CG; n = 8). The subjects in SG and RG, respectively, trained 1.7±0.3 and 1.8±0.3 times weekly on average during the intervention period. Muscle function and body composition were determined before and after 16 and 52 weeks of the intervention period. In SG, BMI was reduced by 1.5% and 3.0% (p<0.05) after 16 and 52 weeks, respectively, unchanged in RG and 2% higher (p<0.05) in CG after 52 weeks of the intervention period. In SG, the response to a glucose tolerance test was 16% lower (p<0.05) after 16 wks, but not after 52 wks, compared to before the intervention period, and unchanged in RG and CG. In SG, superoxide dismutase-2 expression was 59% higher (p<0.05) after 52 wks compared to before the intervention period, and unchanged in RG and CG. In RG, upper body lean mass was 3 and 2% higher (p<0.05) after 16 and 52 wks, respectively, compared to before the intervention period, and unchanged in SG and CG. In RG, Akt-2 expression increased by 28% (p<0.01) and follistatin expression decreased by 38% (p<0.05) during the 52-wk intervention period, and was unchanged in SG and CG. Thus, long-term soccer training reduces BMI and improves anti-oxidative capacity, while long-term resistance training impacts muscle protein enzyme expression and increases lean body mass in elderly men. Trial Registration: ClinicalTrials.gov: NCT01530035.

Monitoring Elite Soccer Players' External Loads Using Real-Time Data.

PubMed

Barrett, Steve

2017-11-01

To assess the validity of measuring locomotor activities and PlayerLoad using real-time (RT) data collection during soccer training. Twenty-nine English soccer players participated. Each player wore the same MEMS device (Micromechanical Electrical Systems; S5, Optimeye; CatapultSports, Melbourne, Australia) during 21 training sessions (N = 331 data sets) in the 2015-16 and 2016-17 seasons. An RT receiver (TRX; Catapultsports, Melbourne, Australia) was used to collect the locomotor activities and PlayerLoad data in RT and compared with the postevent downloaded (PED) data. PlayerLoad and locomotor activities (total distance covered; total high-speed running distance covered, >5.5#x00A0;m/s; total sprinting distance covered, >7 m/s; maximum velocity) were analyzed. Correlations were near perfect for all variables analyzed (r = .98-1.00), with a varied level of noise between RT and PED also (0.3-9.7% coefficient of variation). Locomotor activities and PlayerLoad can use both RT and PED concurrently to quantify a player's physical output during a training session. Caution should be taken with higher-velocity-based locomotor activities during RT compared to PED.

Broad-spectrum health improvements with one year of soccer training in inactive mildly hypertensive middle-aged women.

PubMed

Krustrup, P; Skoradal, M-B; Randers, M B; Weihe, P; Uth, J; Mortensen, J; Mohr, M

2017-12-01

The study tested the hypothesis that long-term soccer training has positive impact on cardiovascular profile, body composition, bone health, and physical capacity in inactive, pre-menopausal women with mild hypertension. The study applied a randomized controlled design in which physically inactive middle-aged women were separated into a soccer training group (n=19; SOC) and a control group (n=12; CON). SOC performed 128±29 (±SD) one-h small-sided soccer training sessions over one year. Blood pressure, body composition, blood lipid profile, and fitness level were determined pre- and post-intervention. Over one year, mean arterial pressure decreased more in SOC than in CON (-5±7 vs +4±5 mmHg; P<.05). Total-body fat mass decreased more (P<.05) in SOC than in CON (-2.5±2.5 vs +0.6±3.2 kg; P<.05), while the change scores for lean body mass were not significantly different in SOC (2.6±2.7 kg) compared to CON (1.1±1.9 kg, P=.09). Over one year, change scores in whole-body bone mineral density (0.004±0.032 vs -0.019±0.026 g·cm 2 ) as well as bone mineral content (30±70 vs -39±113 g) were positive in SOC compared to CON (P<.05). Post-intervention plasma triglycerides decreased more (-0.1±0.7 vs +0.2±0.2 mmol·L -1 ) and HDL cholesterol increased more (0.2±0.7 vs -0.2±0.2 mmol·L -1 ) in SOC than in CON (P<.05). Yo-Yo intermittent endurance level 1 (122±105 vs 2±21%) and 20-m sprint performance (6±6 vs -1±2%) increased more (P<.05) in SOC than in CON. In conclusion, long-term soccer training resulted in broad-spectrum improvements in the health profile of untrained, pre-menopausal women with mild hypertension, including cardiovascular, metabolic, and musculo-skeletal benefits. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Body Size of Male Youth Soccer Players: 1978-2015.

PubMed

Malina, Robert M; Figueiredo, António J; Coelho-E-Silva, Manuel J

2017-10-01

Studies of the body size and proportions of athletes have a long history. Comparisons of athletes within specific sports across time, though not extensive, indicate both positive and negative trends. To evaluate secular variation in heights and weights of male youth soccer players reported in studies between 1978 and 2015. Reported mean ages, heights, and weights of male soccer players 9-18 years of age were extracted from the literature and grouped into two intervals: 1978-99 and 2000-15. A third-order polynomial was fitted to the mean heights and weights across the age range for each interval, while the Preece-Baines model 1 was fitted to the grand means of mean heights and mean weights within each chronological year to estimate ages at peak height velocity and peak weight velocity for each time interval. Third-order polynomials applied to all data points and estimates based on the Preece-Baines model applied to grand means for each age group provided similar fits. Both indicated secular changes in body size between the two intervals. Secular increases in height and weight between 1978-99 and 2000-15 were especially apparent between 13 and 16 years of age, but estimated ages at peak height velocity (13.01 and 12.91 years) and peak weight velocity (13.86 and 13.77 years) did not differ between the time intervals. Although the body size of youth soccer players increased between 1978-99 and 2000-15, estimated ages at peak height velocity and peak weight velocity did not change. The increase in height and weight likely reflected improved health and nutritional conditions, in addition to the selectivity of soccer reflected in systematic selection and retention of players advanced in maturity status, and exclusion of late maturing players beginning at about 12-13 years of age. Enhanced training programs aimed at the development of strength and power are probably an additional factor contributing to secular increases in body weight.

Off-season physiological profiles of elite National Collegiate Athletic Association Division III male soccer players.

PubMed

Miller, Douglas K; Kieffer, H Scott; Kemp, Heather E; Torres, Sylvia E

2011-06-01

The purpose of this study was to develop a profile of soccer-related fitness parameters on elite National Collegiate Athletic Association (NCAA) Division III male soccer players during the off-season. Sixteen underclassmen from a recent NCAA Division III national championship soccer team completed a series of tests across 3 separate occasions over a 15-day period, with adequate recovery time between sessions to eliminate any carryover effect. Physiological parameters measured included aerobic endurance, anaerobic power and capacity, jumping power, agility, hamstring flexibility, and body composition. Descriptive statistics such as the mean (±SD) and range were calculated for each test. Two-tailed Pearson correlations were run to determine significant relationships that existed between variables. Test results were T-Tests (9.9 ± 0.4), Active Knee Extension degrees (-34.2 ± 11.9 right, -34.0 ± 13.9 left), vertical jump (61.8 ± 7.2 cm), percent fat (5.6 ± 1.6), Progressive Aerobic Cardiovascular Endurance Run (PACER) laps (113.2 ± 12.3), estimated VO2max (53.6 ± 2.9 ml · kg(-1) · min(-1)), Wingate peak (802.7 ± 155.6 W), Wingate peak (10.9 ± 1.2 W · kg(-1)), Wingate mean (651.2 ± 101.6 W), Wingate mean (8.9 ± 0.6 W · kg), and Wingate fatigue rate (35.9 ± 8.4%). Strong correlations existed between PACER laps and percent fat, between peak W and peak W · kg(-1), and between peak W and fatigue rate. These results suggest that elite Division III soccer players maintain relatively high fitness levels during the off-season. Additionally, they provide coaches with preliminary norms that can be used to determine off-season training expectations and adjust programs accordingly for their athletes.

Benefits Analysis of the Naval Junior Reserve Officers Training Corps

DTIC Science & Technology

1992-06-01

Football, baseball, softball, soccer , 2086 (54.7) track, swimming, wrestling, weightlifting, volleyball, or other sports) Church youth group 1382 (36.3...clubs a b 78. Academic clubs (For example: uth. science, tlanguae) a b 79. Sports (Football, baseball, softball, soccer , track, a b swimming, wrestling...the Players Champion Golf Tournament Seneca Valley High School, MD Kanzano High School, NM Neptune High School, NJ Episcopal High School, IA Valley

Dietary and performance assessment of elite soccer players during a period of intense training.

PubMed

Rico-Sanz, J; Frontera, W R; Molé, P A; Rivera, M A; Rivera-Brown, A; Meredith, C N

1998-09-01

This study examined the nutritional and performance status of elite soccer players during intense training. Eight male players (age 17+/-2 years) of the Puerto Rican Olympic Team recorded daily activities and food intake over 12 days. Daily energy expenditure was 3,833+/-571 (SD) kcal, and energy intake was 3,952+/-1,071 kcal, of which 53.2+/-6.2% (8.3 g x kg BW(-1)) was from carbohydrates (CHO), 32.4+/-4.0% from fat, and 14.4+/-2.3% from protein. With the exception of calcium, all micronutrients examined were in accordance with dietary guidelines. Body fat was 7.6+/-1.1% of body weight. Time to completion of three runs of the soccer-specific test was 37.65+/-0.62 s, and peak torques of the knee flexors and extensors at 60 degrees x s(-1) were 139+/-6 and 225+/-9 N x m, respectively. Players' absolute amounts of CHO seemed to be above the minimum recommended intake to maximize glycogen storage, but calcium intakes were below recommended. Their body fat was unremarkable, and they had a comparatively good capacity to endure repeated bouts of intense soccer-specific exercise and to exert force with their knee extensors and flexors.

The health profile of professional soccer players: future opportunities for injury prevention.

PubMed

Volpi, Piero; Taioli, Emanuela

2012-12-01

Injuries are a major adverse event during a soccer player's career; they require medical and surgical treatment and rehabilitation and thus may interrupt the player's activity, often with severe physical and psychological sequel. Specialists have tried to identify the risk factors for injuries, in an attempt to discover predictors that could be prevented and or eliminated before the injury occurs, but the results are scarce. This article reviews the epidemiology of the frequency and occurrence of injuries in Italian soccer players, reports a list of preventable risk factors that are associated with injuries, and identifies preventable risk factors. We have identified personal factors (age, previous traumatic events, physical and biological characteristics of the player, life style habits such as smoking, alcohol, and diet, changes in physical-athletic aspects of the players, such as increased muscle strength, and use of medications) as possible risk factors for injuries. However, environmental factors such as changes in training techniques, field composition, and shoes structure may also have a major influence. This summary indicates that appropriate preventive measures can be undertaken to prevent injuries in professional soccer players. Professionals who are in close contacts with the players should be informed of the predictors of injuries and should be trained to intervene and plan appropriate preventive measures.

Oxidative stress status in elite athletes engaged in different sport disciplines

PubMed Central

Hadžović - Džuvo, Almira; Valjevac, Amina; Lepara, Orhan; Pjanić, Samra; Hadžimuratović, Adnan; Mekić, Amel

2014-01-01

Exercise training may increase production of free radicals and reactive oxygen species in different ways. The training type and intensity may influence free radicals production, which leads to differences in oxidative stress status between athletes, but the results of the previous studies are incosistent. The aim of our study was to estimate oxidative stress status in elite athletes engaged in different sport disciplines. The study included 39 male highly skilled professional competitors with international experience (2 Olympic players): 12 wrestlers, 14 soccer players and 13 basketball players in whom we determined the levels of advanced oxidation protein products (AOPP) and malondialdehyde (MDA), as markers of oxidative stress and the total antioxidative capacity (ImAnOX) using commercially available assay kits. The mean AOPP concentration was not significantly different between soccer players, wrestler and basketball players (60.0±23.0 vs. 68.5±30.8 and 80.72±29.1 μmol/L respectively). Mean ImAnOX concentration was not different between soccer players (344.8±35.6 μmol/L), wrestlers (342±36.2 μmol/L) and basketball players (347.95±31.3 μmol/L). Mean MDA concentration was significantly higher in basketball players (1912.1±667.7 ng/mL) compared to soccer players (1060.1±391.0 ng/mL, p=0.003). In spite of this fact, oxidative stress markers levels were increased compared to referral values provided by the manufacturer. Type of sports (soccer, wrestler or basketball) have no impact on the levels of oxidative stress markers. Elite sports engagement is a potent stimulus of oxidative stress that leads to the large recruitment of antioxidative defense. Oxidative stress status monitoring followed by appropriate use of antioxidants is recommended as a part of training regime. PMID:24856375

Reliability and Validity of a Submaximal Warm-up Test for Monitoring Training Status in Professional Soccer Players.

PubMed

Rabbani, Alireza; Kargarfard, Mehdi; Twist, Craig

2018-02-01

Rabbani, A, Kargarfard, M, and Twist, C. Reliability and validity of a submaximal warm-up test for monitoring training status in professional soccer players. J Strength Cond Res 32(2): 326-333, 2018-Two studies were conducted to assess the reliability and validity of a submaximal warm-up test (SWT) in professional soccer players. For the reliability study, 12 male players performed an SWT over 3 trials, with 1 week between trials. For the validity study, 14 players of the same team performed an SWT and a 30-15 intermittent fitness test (30-15IFT) 7 days apart. Week-to-week reliability in selected heart rate (HR) responses (exercise heart rate [HRex], heart rate recovery [HRR] expressed as the number of beats recovered within 1 minute [HRR60s], and HRR expressed as the mean HR during 1 minute [HRpost1]) was determined using the intraclass correlation coefficient (ICC) and typical error of measurement expressed as coefficient of variation (CV). The relationships between HR measures derived from the SWT and the maximal speed reached at the 30-15IFT (VIFT) were used to assess validity. The range for ICC and CV values was 0.83-0.95 and 1.4-7.0% in all HR measures, respectively, with the HRex as the most reliable HR measure of the SWT. Inverse large (r = -0.50 and 90% confidence limits [CLs] [-0.78 to -0.06]) and very large (r = -0.76 and CL, -0.90 to -0.45) relationships were observed between HRex and HRpost1 with VIFT in relative (expressed as the % of maximal HR) measures, respectively. The SWT is a reliable and valid submaximal test to monitor high-intensity intermittent running fitness in professional soccer players. In addition, the test's short duration (5 minutes) and simplicity mean that it can be used regularly to assess training status in high-level soccer players.

Cardiac Parasympathetic Reactivation in Elite Soccer Players During Different Types of Traditional High-Intensity Training Exercise Modes and Specific Tests: Interests and Limits

PubMed Central

Dellal, Alexandre; Casamichana, David; Castellano, Julen; Haddad, Monoem; Moalla, Wassim; Chamari, Karim

2015-01-01

Background: The cardiac parasympathetic reactivation is currently used in soccer with a daily or weekly monitoring. However, previous studies have not investigated how this cardiac parasympathetic reactivation is in elite soccer players along different types of traditional high-intensity training exercise and specific tests. In this context, the present study aim to analyse it and to determine the interests and limits of this type of physiological information. Objectives: The present study aims to examine how different traditional training exercise modes affect the cardiac parasympathetic reactivation function in elite soccer players. Materials and Methods: Twenty-two international soccer players participating in UEFA Champion’s League took part in this study (age: 24.3 ± 4.2 years; height: 178.1 ± 6.2 cm; body mass: 80.3 ± 5.7 kg). Players performed different training methods including: short-duration intermittent exercises (INT) in-line and with changes of direction (COD) (10 - 10 seconds, 15 - 15 seconds, 30 - 30 seconds, e.g. an alternance of 10 - 10 seconds is 10 seconds of running according to the maximal aerobic speed (MAS) and 10-sec of recovery), INT including agility and technical skills (8 - 24-seconds), small-sided-games (SSGs) with and without goalkeepers (2 vs. 2, 3 vs. 3, 4 vs. 4), and repeated sprint ability (RSA) efforts (10 × 20 m, 10 × 30 m, 15 × 20 m). Heart rate (HR) decline was recorded 3 minutes after each exercise. Results: HR declines were greater after the RSA compared to SSGs (P < 0.001) and INT (P < 0.01), especially at 1 min post-exercise. In addition, when the analysis focused on each type of exercise, greater HR declines were observed in on-field players at 1 minute when there was: inclusion of goalkeepers in SSGs (for 2 vs. 2 and 3 vs. 3, P < 0.01); increase of sprint distances or number of sprint repetitions in RSA (P < 0.01); increase of intensity (% of maximal aerobic speed), and the use of COD or inclusion of technical skills during INT, especially for the 30 - 30-seconds. Conclusions: This study revealed that cardiac parasympathetic reactivation function varied after INT, RSA and SSG, but also according to the rules manipulation. Therefore, this study provides interesting information for the training monitoring and players’ recovery profile, with the aim of facilitating a more efficient planning and manipulation of training recovery strategies according to their fitness markers. PMID:26715972

Bone Turnover Markers and Lean Mass in Pubescent Boys: Comparison Between Elite Soccer Players and Controls.

PubMed

Nebigh, Ammar; Abed, Mohamed Elfethi; Borji, Rihab; Sahli, Sonia; Sellami, Slaheddine; Tabka, Zouhair; Rebai, Haithem

2017-11-01

The aim of this study was to examine the relationship between bone mass and bone turnover markers with lean mass (LM) in pubescent soccer players. Two groups participated in this study, which included 65 elite young soccer players who trained for 6-8 hours per week and 60 controls. Bone mineral density; bone mineral content in the whole body, lower limbs, lumbar spine, and femoral neck; biochemical markers of osteocalcin; bone-specific alkaline phosphatase; C-telopeptide type I collagen; and total LM were assessed. Young soccer players showed higher bone mineral density and bone mineral content in the whole body and weight-bearing sites (P < .001). Indeed, the total LM correlated with whole-body bone mineral density and bone mineral content (P < .001). There were significant differences within the bone formation markers and osteocalcin (formation)/C-telopeptide type I collagen (resorption) ratio between young soccer players compared with the control group, but no significant difference in C-telopeptide type I collagen was observed between the 2 groups. This study showed a significant positive correlation among bone-specific alkaline phosphatase, osteocalcin, and total LM (r = .29; r = .31; P < .05) only for the young soccer players. Findings of this study highlight the importance of soccer practice for bone mineral parameters and bone turnover markers during the puberty stage.

Body composition and nutritional assessments in soccer.

PubMed

Rico-Sanz, J

1998-06-01

This review summarizes results from studies investigating the physical characteristics, daily energy expenditures, diets, and effects of nutritional supplements to the habitual diets of soccer players. The results show that players fall within a wide range of stature and body weight, and they are classified as mesomorphs. The body fat of male players is about 10% of body weight, whereas the average for females is about 21%. Energy expenditure for males is about 4,000 kcal on training days and 3,800 kcal on match day, while energy intake reported in other studies is on the order of 3,700 kcal. Carbohydrate (CHO), fat, and protein intakes are about 53, 30, and 14% of energy intake, respectively, the remaining being from alcohol intake. There are indications that CHO supplements might be beneficial during soccer performance. However, more research is needed to clarify the importance of branched-chain amino acid and creatine supplementation in soccer.

Do soccer and Zumba exercise improve fitness and indicators of health among female hospital employees? A 12-week RCT.

PubMed

Barene, S; Krustrup, P; Jackman, S R; Brekke, O L; Holtermann, A

2014-12-01

This randomized controlled study investigated the effectiveness of soccer and Zumba on fitness and health indicators in female participants recruited from a workplace. One hundred seven hospital employees were cluster-randomized to either a soccer group (SG), Zumba group (ZG), or control group (CG). Intervention effects for the two training groups were compared with CG. The training was conducted outside working hours as 2-3 1-h sessions per week for 12 weeks. Peak oxygen uptake (VO2peak ), fat percentage, fat mass, bone mineral content, and plasma osteocalcin were measured before and after the intervention period. Based on intention-to-treat-analyses, SG significantly improved the VO2peak relative to body mass (5%; P = 0.02) and decreased heart rate during 100-W cycle exercise (-7 bpm; P = 0.01), total body fat percentage (-1.1%; P = 0.002), and total body fat mass (-1.0 kg; P = 0.001) compared with CG. ZG significantly improved the VO2peak relative to body mass (5%; P = 0.03) and decreased total fat mass (-0.6 kg; P < 0.05) compared with CG. Plasma osteocalcin increased in SG (21%; P < 0.001) and ZG (10%; P = 0.01) compared with CG. The present study indicates that workplace initiated short-term soccer training as well as Zumba outside working hours may result in fitness and modest health benefits among female hospital employees. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Microfinance for Post-Conflict Peacebuilding

DTIC Science & Technology

2012-04-21

include: conflict resolution, health, nutrition , education, and literacy training.30 Speaking of primary and secondary goals, Mercy Corps International...processes; or by funding processes in which members of opposing social groups participate (e.g. soccer games, leader meetings, training workshops).46

The effect of carbohydrate ingestion on performance during a simulated soccer match.

PubMed

Goedecke, Julia H; White, Nicholas J; Chicktay, Waheed; Mahomed, Hafsa; Durandt, Justin; Lambert, Michael I

2013-12-16

This study investigated how performance was affected after soccer players, in a postprandial state, ingested a 7% carbohydrate (CHO) solution compared to a placebo (0% CHO) during a simulated soccer match. Using a double-blind placebo-controlled design, 22 trained male league soccer players (age: 24 ± 7 years, wt: 73.4 ± 12.0 kg, VO2max: 51.8 ± 4.3 mL O2/kg/min) completed two trials, separated by 7 days, during which they ingested, in random order, 700 mL of either a 7% CHO or placebo drink during a simulated soccer match. Ratings of perceived exertion (RPE), agility, timed and run to fatigue were measured during the trials. Change in agility times was not altered by CHO vs. placebo ingestion (0.57 ± 1.48 vs. 0.66 ± 1.00, p = 0.81). Timed runs to fatigue were 381 ± 267 s vs. 294 ± 159 s for the CHO and placebo drinks, respectively (p = 0.11). Body mass modified the relationship between time to fatigue and drink ingestion (p = 0.02 for drink × body mass), such that lower body mass was associated with increased time to fatigue when the players ingested CHO, but not placebo. RPE values for the final stage of the simulated soccer match were 8.5 ± 1.7 and 8.6 ± 1.5 for the CHO and placebo drinks respectively (p = 0.87). The group data showed that the 7% CHO solution (49 g CHO) did not significantly improve performance during a simulated soccer match in league soccer players who had normal pre-match nutrition. However, when adjusting for body mass, increasing CHO intake was associated with improved time to fatigue during the simulated soccer match.

The Effect of Carbohydrate Ingestion on Performance during a Simulated Soccer Match

PubMed Central

Goedecke, Julia H.; White, Nicholas J.; Chicktay, Waheed; Mahomed, Hafsa; Durandt, Justin; Lambert, Michael I.

2013-01-01

Aim: This study investigated how performance was affected after soccer players, in a postprandial state, ingested a 7% carbohydrate (CHO) solution compared to a placebo (0% CHO) during a simulated soccer match. Methods: Using a double-blind placebo-controlled design, 22 trained male league soccer players (age: 24 ± 7 years, wt: 73.4 ± 12.0 kg, VO2max: 51.8 ± 4.3 mL O2/kg/min) completed two trials, separated by 7 days, during which they ingested, in random order, 700 mL of either a 7% CHO or placebo drink during a simulated soccer match. Ratings of perceived exertion (RPE), agility, timed and run to fatigue were measured during the trials. Results: Change in agility times was not altered by CHO vs. placebo ingestion (0.57 ± 1.48 vs. 0.66 ± 1.00, p = 0.81). Timed runs to fatigue were 381 ± 267 s vs. 294 ± 159 s for the CHO and placebo drinks, respectively (p = 0.11). Body mass modified the relationship between time to fatigue and drink ingestion (p = 0.02 for drink × body mass), such that lower body mass was associated with increased time to fatigue when the players ingested CHO, but not placebo. RPE values for the final stage of the simulated soccer match were 8.5 ± 1.7 and 8.6 ± 1.5 for the CHO and placebo drinks respectively (p = 0.87). Conclusions: The group data showed that the 7% CHO solution (49 g CHO) did not significantly improve performance during a simulated soccer match in league soccer players who had normal pre-match nutrition. However, when adjusting for body mass, increasing CHO intake was associated with improved time to fatigue during the simulated soccer match. PMID:24352094

The preventive effect of the Nordic hamstring exercise on hamstring injuries in amateur soccer players: study protocol for a randomised controlled trial.

PubMed

van der Horst, Nick; Smits, Dirk Wouter; Petersen, Jesper; Goedhart, Edwin A; Backx, Frank J G

2014-08-01

Hamstring injuries are the most common muscle injury in male amateur soccer players and have a high rate of recurrence, often despite extensive treatment and long rehabilitation periods. Eccentric strength and flexibility are recognised as important modifiable risk factors, which have led to the development of eccentric hamstring exercises, such as the Nordic hamstring exercise. As the effectiveness of the Nordic hamstring exercise in reducing hamstring injuries has never been investigated in amateur soccer players, the aim of this study is to investigate the effect of this exercise on the incidence and severity of hamstring injuries in male amateur soccer players. An additional aim is to determine whether flexibility is associated with hamstring injuries. Cluster-randomised controlled trial with soccer teams as the unit of cluster. Dutch male amateur soccer players, aged 18-40 years, were allocated to an intervention or control group. Both study groups continued regular soccer training during 2013, but the intervention group additionally performed the Nordic hamstring exercise (25 sessions over 13 weeks). Primary outcomes are the incidence of initial and recurrent hamstring injury and injury severity. Secondary outcomes are hamstring-and-lower-back flexibility and compliance. Compliance to the intervention protocol was also monitored. Eccentric hamstring strength exercises are hypothesised to reduce the incidence of hamstring injury among male amateur soccer players by 70%. The prevention of such injuries will be beneficial to soccer players, clubs, football associations, health insurance companies and society. NTR3664. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Understanding mental toughness in Australian soccer: perceptions of players, parents, and coaches.

PubMed

Coulter, Tristan J; Mallett, Clifford J; Gucciardi, Daniel F

2010-05-01

We explored mental toughness in soccer using a triangulation of data capture involving players (n = 6), coaches (n = 4), and parents (n = 5). Semi-structured interviews, based on a personal construct psychology (Kelly, 1955/1991) framework, were conducted to elicit participants' perspectives on the key characteristics and their contrasts, situations demanding mental toughness, and the behaviours displayed and cognitions employed by mentally tough soccer players. The results from the research provided further evidence that mental toughness is conceptually distinct from other psychological constructs such as hardiness. The findings also supported Gucciardi, Gordon, and Dimmock's (2009) process model of mental toughness. A winning mentality and desire was identified as a key attribute of mentally tough soccer players in addition to other previously reported qualities such as self-belief, physical toughness, work ethic/motivation, and resilience. Key cognitions reported by mentally tough soccer players enabled them to remain focused and competitive during training and matches and highlighted the adoption of several forms of self-talk in dealing with challenging situations. Minor revisions to Gucciardi and colleagues' definition of mental toughness are proposed.

[Motivational climate and coaches' communication style predict young soccer players' commitment].

PubMed

Torregrosa, Miquel; Sousa, Catarina; Viladrich, Carme; Villamarín, Francisco; Cruz, Jaume

2008-05-01

The purpose of this research was to study the role of coaches' communication style and coach-created motivational climate in young soccer players' enjoyment and commitment. Four hundred and fifteen young soccer players of high competitive level in the age range from 14 to 16 completed the following questionnaires: a) coach-induced perceived motivational climate (PMCSQ-2), b) coaches' behaviour perception (CBAS-PBS), and c) sport commitment (SCQ). Results showed that coach-created motivational climate correlated highly with the perception of coaches' communication style. Moreover, coach-created motivational climate and communication style significantly determines players' sport commitment and enjoyment. Discussion focuses on the importance of seeking and training credible coaches that favours athletes' commitment.

Soccer training: high-intensity interval training is mood disturbing while small sided games ensure mood balance.

PubMed

Selmi, Okba; Haddad, Monoem; Majed, Lina; Ben Khalifa, Wissam; Hamza, Marzougui; Chamari, Karim

2017-05-09

BACKGROUNDː The aim of the study was to compare the effects of high-intensity intermittent training (HIIT) versus small-sided games (SSG) in soccer on both the physiological responses and the mood state of players. Sixteen professional soccer players took part in the study (age: 24.1±0.9 years). Testing of players was conducted on separate days in a randomized and counter-balanced order (each training session: 28-min: 4x4 minutes work with 3-min of passive recovery in-between). Effort: HIIT: intermittent 15-s runs at 110% maximal aerobic speed with 15-s of passive recovery in-between. SSG: 4 versus 4 players on a 25x35m pitch size with full-involvement play. Psychological responses before- and after- each training-session were assessed using the profile of mood-state (POMS: Tension, Depression, Anger, Vigor, Fatigue, and Confusion). The players' heart rate (HR) was continuously measured, whereas ratings of perceived exertion (RPE) and blood lactate concentration ([La]) were collected ~3-min after each training-session. HIIT and SSG showed no significant difference in HR, RPE and [La] responses. The HIIT compared with SSG resulted in: an increased total mood disturbance (p<0.001), tension (p<0.05), fatigue (p<0.01) and a decreased vigor (p<0.001). Both HIIT and SSG sessions induced similar physiological responses, in contrast, HIIT produced a mood disturbance while SSG ensured mood balance. Practitioners could choose between these two exercises according to the objective of their training, keeping in mind the mood-related advantages of the SSG shown in the present study.

Prevalence of tinea pedis in professional and college soccer players versus non-athletes.

PubMed

Pickup, Tiffany L; Adams, Brian B

2007-01-01

To assess and compare the prevalence of tinea pedis among professional soccer players, college soccer players, and non-athletes. We sought to assess the prevalence of various risk factors and their association with tinea pedis among these different groups. Survey study. United States. Members of a United Soccer League (USL) professional team (N = 16), male (N = 16) and female (N = 14) NCAA soccer teams at a local college, and male (N = 15) and female (N = 15) non-athletes from a local medical school. All participants anonymously answered questions on their risk factors for tinea pedis and underwent physical and mycological examinations. Clinical exam, potassium hydroxide solution (KOH), and culture. Tinea pedis infected 69% professional soccer players (11 of 16) compared with 69% of male college soccer players (11 of 16) and 43% of female college soccer players (6 of 14), whereas non-athletes demonstrated significantly less tinea pedis (P < 0.001), including 20% of male non-athletes (3 of 15) and 0% of female non-athletes (0 of 15). These results indicate a need for improved primary prevention of tinea pedis among athletes. A preventive program involving education and coach participation is needed to target these individuals.

Development and Application of the STEAM Education Program Based on the Soccer Robot for Elementary Students

ERIC Educational Resources Information Center

Yoon, Ma-byong; Baek, Je-eun

2018-01-01

The purpose of this article was to develop an elementary school robot STEAM program and explore the possibility of field applications. To this end, the authors extracted the contents related to school achievement standards for 5th and 6th grade curricula around the topic of robot soccer, incorporating a relevant curriculum based on the extracted…

Vitamin D and Exercise Performance in Professional Soccer Players

PubMed Central

Koundourakis, Nikolaos E.; Androulakis, Nikolaos E.; Malliaraki, Niki; Margioris, Andrew N.

2014-01-01

Aim The current study had two aims. The primary purpose was to examine the association between serum vitamin D levels and the ergometric evaluation of muscle strength, aerobic capacity, and speed in professional soccer players. The secondary aim was to evaluate the effects of the soccer off-season period on serum vitamin D levels. Methods Sixty-seven Caucasian male soccer players (age 25.6±6.2 and height 1.81±0.08 m), members of two Greek Superleague Soccer teams and one Football-league championship team participated in this study. Exercise performance testing for the determination of squat jump (SJ), countermovement jump (CMJ), 10 (10 m) and 20 meters (20 m) sprint performance, maximal oxygen consumption (VO2max), anthropometry, and blood sampling were performed before (pre) and after (post) the six-week off-season period. Results Analysis of our results showed the following: (a) a significant correlations between serum vitamin D levels and performance parameters in both pre (SJ; P<0.001, CMJ; P<0.001, VO2max; P<0.001, 10 m; P<0.001, and 20 m; P<0.001) and post (SJ; P<0.001, CMJ; P<0.001, VO2max; P = 0.006, 10 m; P<0.001, and 20 m; P<0.001) experimental sessions. (b) Vitamin D concentration increased significantly (P<0.001) following the six-week off-season period compared to baseline, while at the same time all measured performance parameters decreased (SJ; P<0.001, CMJ; P<0.001, 10 m; P<0.001, 20 m; P<0.001, VO2max; P<0.001). Discussion Our findings suggest that vitamin D levels are associated with the ergometric evaluation of muscle strength, as expressed by SJ and CMJ, sprinting capacity, and VO2max in professional soccer players, irrespective the levels of performance. Furthermore, our data reaffirm the importance of UVB on serum vitamin D levels. Moreover, reductions in exercise training stress may also have beneficial effects on vitamin D levels, suggesting a possible association of its levels and the training-induced stress. Our results indicate a possibly bidirectional interaction between soccer performance indices and vitamin D levels. PMID:24992690

Relationship between balance ability, training and sports injury risk.

PubMed

Hrysomallis, Con

2007-01-01

Traditionally, balance training has been used as part of the rehabilitation programme for ankle injuries. More recently, balance training has been adopted to try and prevent injuries to the ankle and knee joints during sport. The purpose of this review is to synthesise current knowledge in the area of balance ability, training and injury risk, highlight the findings and identify any future research needs. A number of studies have found that poor balance ability is significantly related to an increased risk of ankle injuries in different activities. This relationship appears to be more common in males than females. Multifaceted intervention studies that have included balance training along with jumping, landing and agility exercises have resulted in a significant decrease in ankle or knee injuries in team handball, volleyball and recreational athletes. It is unknown which component of the multifaceted intervention was most effective and whether the effects are additive. As a single intervention, balance training has been shown to significantly reduce the recurrence of ankle ligament injuries in soccer, volleyball and recreational athletes; however, it has not been clearly shown to reduce ankle injuries in athletes without a prior ankle injury. Balance training on its own has also been shown to significantly reduce anterior cruciate ligament injuries in male soccer players. Surprisingly, it was also found to be significantly associated with an increased risk of major knee injuries in female soccer players and overuse knee injuries in male and female volleyball players. The studies with the contrasting findings differed in aspects of their balance training programmes. It would appear that balance training, as a single intervention, is not as effective as when it is part of a multifaceted intervention. Research is required to determine the relative contribution of balance training to a multifaceted intervention so as to generate an effective and efficient preventative programme that can be adopted by athletes of most levels.

Ball-Sport Endurance and Sprint Test (BEAST90): validity and reliability of a 90-minute soccer performance test.

PubMed

Williams, Jeremy D; Abt, Grant; Kilding, Andrew E

2010-12-01

The aim of this study was to determine the validity and reliability of a 90-minute soccer performance test: Ball-sport Endurance and Sprint Test (BEAST90). Fifteen healthy male amateur soccer players participated and attended 5 testing sessions over a 10-day period to perform physiologic and soccer-specific assessments. This included familiarization sessions and 2 full trials of the BEAST90, separated by 7 days. The total 90-minute distance, mean percent peak heart rate (HRpeak), and estimated percent peak oxygen uptake of the BEAST90 were 8,097 ± 458 m, 85 ± 5% and 82 ± 14%, respectively. Measures obtained from trial 1 and trial 2 were not significantly different (p > 0.05). Reliability of measures over 90 minutes ranged from 0.9-25.5% (% typical error). The BEAST90 protocol replicated soccer match play in terms of time, movement patterns, physical demands (volume and intensity), distances, and mean and HRpeak values, as well as having an aerobic load similar to that observed during a soccer match. Reproducibility of key physical measures during the BEAST90 were mostly high, suggesting good reliability. The BEAST90 could be used in studies that wish to determine the effects of training or nutritional interventions on prolonged intermittent physical performance.

Mental fatigue impairs soccer-specific decision-making skill.

PubMed

Smith, Mitchell R; Zeuwts, Linus; Lenoir, Matthieu; Hens, Nathalie; De Jong, Laura M S; Coutts, Aaron J

2016-07-01

This study aimed to investigate the impact of mental fatigue on soccer-specific decision-making. Twelve well-trained male soccer players performed a soccer-specific decision-making task on two occasions, separated by at least 72 h. The decision-making task was preceded in a randomised order by 30 min of the Stroop task (mental fatigue) or 30 min of reading from magazines (control). Subjective ratings of mental fatigue were measured before and after treatment, and mental effort (referring to treatment) and motivation (referring to the decision-making task) were measured after treatment. Performance on the soccer-specific decision-making task was assessed using response accuracy and time. Visual search behaviour was also assessed throughout the decision-making task. Subjective ratings of mental fatigue and effort were almost certainly higher following the Stroop task compared to the magazines. Motivation for the upcoming decision-making task was possibly higher following the Stroop task. Decision-making accuracy was very likely lower and response time likely higher in the mental fatigue condition. Mental fatigue had unclear effects on most visual search behaviour variables. The results suggest that mental fatigue impairs accuracy and speed of soccer-specific decision-making. These impairments are not likely related to changes in visual search behaviour.

Game Demands of Seven-A-Side Soccer in Young Players.

PubMed

Barbero-Alvarez, José C; Gómez-López, Maite; Castagna, Carlo; Barbero-Alvarez, Verónica; Romero, David V; Blanchfield, Anthony W; Nakamura, Fábio Y

2017-07-01

Barbero-Alvarez, JC, Gómez-López, M, Castagna, C, Barbero-Alvarez, V, Romero, DV, Blanchfield, AW, and Nakamura, FY. Game demands of seven-a-side soccer in young players. J Strength Cond Res 31(7): 1771-1779, 2017-The aim of this study was to examine the activity patterns and physiological demands of 7-a-side youth soccer matches across 2 chronological age categories (U12 and U14). Twenty-two soccer players of a national youth soccer academy were investigated. Players of each age category performed 2 training matches (2 × 25 minutes) and were monitored by global positioning system and heart rate monitor units. Players of both categories covered similar total distance (5,348 ± 307 m), at similar mean heart rate values (86 ± 4% of maximum). However, the number of high-intensity runs (82.5 ± 17.4 vs. 69.7 ± 15.2) and total distance covered during sprints (264 ± 207 vs. 128 ± 74 m) were significantly (p ≤ 0.05) higher in U14 compared with U12. The results suggest a highly demanding nature of 7-a-side soccer for skilled players, with physical maturity possibly influencing the match-related high-intensity performance at these ages.

Proprioception and ankle injuries in soccer.

PubMed

Ergen, Emin; Ulkar, Bülent

2008-01-01

Because soccer attracts many participants and leads to a substantial number of injuries, especially of the lower extremities, it is important to study possibilities for injury prevention and proper rehabilitation to return safely to activities. Ankle sprains can be prevented by external ankle supports and proprioceptive-coordination training, especially in athletes with previous ankle sprains. Proprioception is a broad concept that includes balance and postural control with visual and vestibular contributions, joint kinesthesia, position sense, and muscle reaction time. Proprioceptive feedback is crucial in the conscious and unconscious awareness of a joint or limb in motion. Enhancement of functional joint stability by proprioceptive (or neuromuscular) training is important both in prevention and rehabilitation of athletic injuries.

Practitioners' Perceptions of the Soccer Extra-Time Period: Implications for Future Research.

PubMed

Harper, Liam D; Fothergill, Melissa; West, Daniel J; Stevenson, Emma; Russell, Mark

2016-01-01

Qualitative research investigating soccer practitioners' perceptions can allow researchers to create practical research investigations. The extra-time period of soccer is understudied compared to other areas of soccer research. Using an open-ended online survey containing eleven main and nine sub questions, we gathered the perceptions of extra-time from 46 soccer practitioners, all working for different professional soccer clubs. Questions related to current practices, views on extra-time regulations, and ideas for future research. Using inductive content analysis, the following general dimensions were identified: 'importance of extra-time', 'rule changes', 'efficacy of extra-time hydro-nutritional provision', 'nutritional timing', 'future research directions', 'preparatory modulations' and 'recovery'. The majority of practitioners (63%) either agreed or strongly agreed that extra-time is an important period for determining success in knockout football match-play. When asked if a fourth substitution should be permitted in extra-time, 67% agreed. The use of hydro-nutritional strategies prior to extra-time was predominately considered important or very important. However; only 41% of practitioners felt that it was the most important time point for the use of nutritional products. A similar number of practitioners account (50%) and do not (50%) account for the potential of extra-time when training and preparing players and 89% of practitioners stated that extra-time influences recovery practices following matches. In the five minute break prior to extra-time, the following practices (in order of priority) were advocated to players: hydration, energy provision, massage, and tactical preparations. Additionally, 87% of practitioners advocate a particular nutritional supplementation strategy prior to extra-time. In order of importance, practitioners see the following as future research areas: nutritional interventions, fatigue responses, acute injury risk, recovery modalities, training paradigms, injury epidemiology, and environmental considerations. This study presents novel insight into the practitioner perceptions of extra-time and provides information to readers about current applied practices and potential future research opportunities.

Movement analysis of Australian national league soccer players using global positioning system technology.

PubMed

Wehbe, George M; Hartwig, Timothy B; Duncan, Craig S

2014-03-01

Player activity profiles of match play provide valuable information for optimal athlete training prescriptions, competition strategies, and managing load and recovery and are currently lacking in elite Australian-league (A-League) soccer. The aims of the study were, therefore, to (a) determine match activity profiles for elite A-League soccer players and make match-half and positional comparisons and (b) examine the effect of situational factors including evolving match status (drawing, winning, or losing) and goals being scored and conceded on selected match activity profile variables. Global positioning system tracking devices were used to determine activity profiles of 19 elite male adult soccer players during 8 preseason matches (n = 95 files). Total distance, average speed, high-intensity running (HIR) distance, and very high-intensity running distance decreased from the first to the second half by 7.92, 9.47, 10.10, and 10.99%, respectively. Midfielders covered 11.69% more total distance, 28.08% more HIR distance, and had a 10.93% higher average speed than defenders (p ≤ 0.05; d = 1.90, 1.03, and 1.83, respectively). Attackers performed 27.50 and 30.24% less medium accelerations than defenders and midfielders, respectively (p < 0.01; d = 1.54, and 1.73). When the team was winning, average speed was 4.17% lower than when the team was drawing (p ≤ 0.05, d = 0.32). Scoring or conceding goals did not appear to affect HIR. This study adds to limited knowledge of match demands in elite A-League soccer. The match activity profiles provide descriptive benchmarks that could be used to make comparisons with other elite level soccer populations while also providing a framework for game-specific training prescription, competition strategy, and load management. The generalization that defenders experience a relatively lower match load may be questionable given their relatively high acceleration and deceleration demands.

Kinetic Post-match Fatigue in Professional and Youth Soccer Players During the Competitive Period

PubMed Central

Djaoui, Leo; Diaz-Cidoncha Garcia, Jorge; Hautier, Christophe; Dellal, Alexandre

2016-01-01

Background No previous research has analysed kinetic fatigue of elite adult players and elite youth players during the competitive period. Objectives The aim of the present study was to analyse kinetic post-match fatigue in professional and youth soccer players during the competitive period. Materials and Methods resting heart rate (HRrest), post-effort recovery heart rate (HRrecovery), rate of perceived exertion fatigue (RPEf), muscle soreness and blood samples with creatine kinase (CK) and resting lactate (La) from nine professional soccer players were measured immediately before, 24 hour and 48 hour after two official French first league matches (Ligue 1) whereas RPEf, HRrest, and 20m speed performance (speed-20 m) were measured in ten U-17 elite players immediately before, 24 hour and 48h after a friendly match. Results for professionals, a soccer match elevated all physiological markers during the next 24 hours (P < 0.05); only HRrecovery remained significantly different 48 hours after the match (P < 0.05) whereas there was no variation of HRrest, RPEf, and speed-20m, which were elevated until 24h and got back to reference values 48 hours after the match (P < 0.05) for the U17 players. Comparing the two groups, HRrest results remained lower all the time for professionals, and RPEf was lower for U-17, 24 hours after the match (P < 0.05). Conclusions Independent of their level, professional soccer players, need 48 hours to recover after an official match. Professionals gain more fatigue than young players after a match, but recover as fast. Thus, they recover more efficiently especially due to a better physical condition and fitness training. It is expected that the results showed in the study help elite soccer and fitness coaches to manage the training load of the team according to the match. PMID:27217927

Practitioners' Perceptions of the Soccer Extra-Time Period: Implications for Future Research

PubMed Central

Harper, Liam D.; Fothergill, Melissa; West, Daniel J.; Stevenson, Emma; Russell, Mark

2016-01-01

Qualitative research investigating soccer practitioners’ perceptions can allow researchers to create practical research investigations. The extra-time period of soccer is understudied compared to other areas of soccer research. Using an open-ended online survey containing eleven main and nine sub questions, we gathered the perceptions of extra-time from 46 soccer practitioners, all working for different professional soccer clubs. Questions related to current practices, views on extra-time regulations, and ideas for future research. Using inductive content analysis, the following general dimensions were identified: ‘importance of extra-time’, ‘rule changes’, ‘efficacy of extra-time hydro-nutritional provision’, ‘nutritional timing’, ‘future research directions’, ‘preparatory modulations’ and ‘recovery’. The majority of practitioners (63%) either agreed or strongly agreed that extra-time is an important period for determining success in knockout football match-play. When asked if a fourth substitution should be permitted in extra-time, 67% agreed. The use of hydro-nutritional strategies prior to extra-time was predominately considered important or very important. However; only 41% of practitioners felt that it was the most important time point for the use of nutritional products. A similar number of practitioners account (50%) and do not (50%) account for the potential of extra-time when training and preparing players and 89% of practitioners stated that extra-time influences recovery practices following matches. In the five minute break prior to extra-time, the following practices (in order of priority) were advocated to players: hydration, energy provision, massage, and tactical preparations. Additionally, 87% of practitioners advocate a particular nutritional supplementation strategy prior to extra-time. In order of importance, practitioners see the following as future research areas: nutritional interventions, fatigue responses, acute injury risk, recovery modalities, training paradigms, injury epidemiology, and environmental considerations. This study presents novel insight into the practitioner perceptions of extra-time and provides information to readers about current applied practices and potential future research opportunities. PMID:27384693

Comparison of Two Types of Warm-Up Upon Repeated-Sprint Performance in Experienced Soccer Players.

PubMed

van den Tillaar, Roland; von Heimburg, Erna

2016-08-01

van den Tillaar, R and von Heimburg, E. Comparison of two types of warm-up upon repeated-sprint performance in experienced soccer players. J Strength Cond Res 30(8): 2258-2265, 2016-The aim of the study was to compare the effects of a long warm-up and a short warm-up upon repeated-sprint performance in soccer players. Ten male soccer players (age, 21.9 ± 1.9 years; body mass, 77.7 ± 8.3 kg; body height, 1.85 ± 0.03 m) conducted 2 types of warm-ups with 1 week in between: a long warm-up (20 minutes: LWup) and a short warm-up (10 minutes: SWup). Each warm-up was followed by a repeated-sprint test consisting of 8 × 30 m sprints with a new start every 30th second. The best sprint time, total sprinting time, and % decrease in time together with heart rate, lactate, and rate of perceived exertion (RPE) were measured. No significant differences in performance were found for the repeated-sprint test parameters (total sprint time: 35.99 ± 1.32 seconds [LWup] and 36.12 ± 0.96 seconds [SWup]; best sprint time: 4.32 ± 0.13 seconds [LWup] and 4.30 ± 0.10 seconds [SWup]; and % sprint decrease: 4.16 ± 2.15% [LWup] and 5.02 ± 2.07% [SWup]). No differences in lactate concentration after the warm-up and after the repeated-sprint test were found. However, RPE and heart rate were significantly higher after the long warm-up and the repeated-sprint test compared with the short warm-up. It was concluded that a short warm-up is as effective as a long warm-up for repeated sprints in soccer. Therefore, in regular training, less warm-up time is needed; the extra time could be used for important soccer skill training.

The preventive effect of the nordic hamstring exercise on hamstring injuries in amateur soccer players: a randomized controlled trial.

PubMed

van der Horst, Nick; Smits, Dirk-Wouter; Petersen, Jesper; Goedhart, Edwin A; Backx, Frank J G

2015-06-01

Hamstring injuries are the most common muscle injuries in soccer, and they have a high rate of recurrence. Eccentric hamstrings strength is recognized as an important modifiable risk factor. This led to the development of prevention exercises such as the nordic hamstring exercise (NHE). The effectiveness of the NHE on hamstring injury prevention has never been investigated in amateur soccer. To investigate the preventive effect of the NHE on the incidence and severity of hamstring injuries in male amateur soccer players. Randomized controlled trial; Level of evidence, 1. Male amateur soccer players (age, mean ± SD, 24.5 ± 3.8 years) from 40 teams were randomly allocated to an intervention (n = 20 teams, 292 players) or control group (n = 20 teams, 287 players). The intervention group was instructed to perform 25 sessions of NHE in a 13-week period. Both the intervention and control groups performed regular soccer training and were followed for hamstring injury incidence and severity during the 2013 calendar year. At baseline, personal characteristics (eg, age, injury history, field position) were gathered from all participants via a questionnaire. Primary outcome was injury incidence. Secondary outcomes were injury severity and compliance with the intervention protocol. A total of 38 hamstring injuries were recorded, affecting 36 of 579 players (6.2%). The overall injury incidence rate was 0.7 (95% CI, 0.6-0.8) per 1000 player hours, 0.33 (95% CI, 0.25-0.46) in training, and 1.2 (95% CI, 0.82-1.94) in matches. Injury incidence rates were significantly different between the intervention (0.25; 95% CI, 0.19-0.35) and control groups (0.8; 95% CI, 0.61-1.15), χ(2)(1, n = 579) = 7.865; P = .005. The risk for hamstring injuries was reduced in the intervention group compared with the control group (odds ratio, 0.282; 95% CI, 0.110-0.721) and was statistically significant (P = .005). No statistically significant differences were identified between the intervention and control groups regarding injury severity. Compliance with the intervention protocol was 91%. Incorporating the NHE protocol in regular amateur training significantly reduces hamstring injury incidence, but it does not reduce hamstring injury severity. Compliance with the intervention was excellent. © 2015 The Author(s).

Effects of a Special Olympics Unified Sports Soccer Program on Psycho-Social Attributes of Youth with and without Intellectual Disability

ERIC Educational Resources Information Center

Ozer, D.; Baran, F.; Aktop, A.; Nalbant, S.; Aglamis, E.; Hutzler, Y.

2012-01-01

The purpose of the study was to investigate the effects of a Special Olympics (SO) Unified Sports (UNS) soccer program on psycho-social attributes of youth with and without intellectual disabilities (ID). Participants were 76 male youth with (n = 38) and without (n = 38) ID. Participants with ID were randomly allocated into a SO athletes group (n…

The preventive effect of the bounding exercise programme on hamstring injuries in amateur soccer players: the design of a randomized controlled trial.

PubMed

Van de Hoef, S; Huisstede, B M A; Brink, M S; de Vries, N; Goedhart, E A; Backx, F J G

2017-08-22

Hamstring injuries are the most common muscle injury in amateur and professional soccer. Most hamstring injuries occur in the late swing phase, when the hamstring undergoes a stretch-shortening cycle and the hamstring does a significant amount of eccentric work. The incidence of these injuries has not decreased despite there being effective injury prevention programmes focusing on improving eccentric hamstring strength. As this might be because of poor compliance, a more functional injury prevention exercise programme that focuses on the stretch-shortening cycle might facilitate compliance. In this study, a bounding exercise programme consisting of functional plyometric exercises is being evaluated. A cluster-randomized controlled trial (RCT). Male amateur soccer teams (players aged 18-45 years) have been randomly allocated to intervention and control groups. Both groups are continuing regular soccer training and the intervention group is additionally performing a 12-week bounding exercise programme (BEP), consisting of a gradual build up and maintenance programme for the entire soccer season. The primary outcome is hamstring injury incidence. Secondary outcome is compliance with the BEP during the soccer season and 3 months thereafter. Despite effective hamstring injury prevention programmes, the incidence of these injuries remains high in soccer. As poor compliance with these programmes may be an issue, a new plyometric exercise programme may encourage long-term compliance and is expected to enhance sprinting and jumping performance besides preventing hamstring injuries. NTR6129 . Retrospectively registered on 1 November 2016.

Cardiorespiratory responses to Yo-yo Intermittent Endurance Test in nonelite youth soccer players.

PubMed

Castagna, Carlo; Impellizzeri, Franco M; Belardinelli, Romualdo; Abt, Grant; Coutts, Aaron; Chamari, Karim; D'Ottavio, Stefano

2006-05-01

This study examined the validity of the Yo-yo Intermittent Endurance Test (Level 1; YYIET) as indicator of aerobic power in youth soccer players. Cardiorespiratory responses were determined in 18 moderately trained nonelite youth soccer players (age, 16.6 +/- 0.8 years; height, 178.7 +/- 6.2 cm; body mass, 69.8 +/- 6.0 kg; VO2peak, 52.8 +/- 7.4 ml x kg(-1) x min(-1)) while performing the YYIET and an incremental treadmill test. Maximal heart rate (HRmax), respiratory exchange ratio (RER), O2 pulse, VO2peak, and maximal ventilation (VEmax) were measured. Group YYIET VO2peak, HRmax, RER, and O2 pulse were not significantly different from treadmill responses (p > 0.05). VEmax was significantly lower (p < 0.05) during the YYIET compared to the treadmill condition. No significant correlation was found between treadmill VO2peak and YYIET performance (p > 0.05). This study showed that the YYIET elicits peak VO2 and HR responses. However, YYIET performance results were not related to VO2peak measured in laboratory. Furthermore, the individual VO2peak reached during the TM did not reflect the VO2peak obtained during the YYIET, as shown by the large limits of agreement. As a consequence, compared to other shuttle run field tests, YYIET seems to be a weak indicator of aerobic power in youth moderately trained youth soccer player.

Progression of mechanical properties during on-field sprint running after returning to sports from a hamstring muscle injury in soccer players.

PubMed

Mendiguchia, J; Samozino, P; Martinez-Ruiz, E; Brughelli, M; Schmikli, S; Morin, J-B; Mendez-Villanueva, A

2014-07-01

The objectives of this study were to examine the consequences of an acute hamstring injury on performance and mechanical properties of sprint-running at the time of returning to sports and after the subsequent ~2 months of regular soccer training after return. 28 semi-professional male soccer players, 14 with a recent history of unilateral hamstring injury and 14 without prior injury, participated in the study. All players performed two 50-m maximal sprints when cleared to return to play (Test 1), and 11 injured players performed the same sprint test about 2 months after returning to play (Test 2). Sprint performance (i. e., speed) was measured via a radar gun and used to derive linear horizontal force-velocity relationships from which the following variables obtained: theoretical maximal velocity (V(0)), horizontal force (F(H0)) and horizontal power (Pmax). Upon returning to sports the injured players were moderately slower compared to the uninjured players. F H0 and Pmax were also substantially lower in the injured players. At Test 2, the injured players showed a very likely increase in F(H0) and Pmax concomitant with improvements in early acceleration performance. Practitioners should consider assessing and training horizontal force production during sprint running after acute hamstring injuries in soccer players before they return to sports. © Georg Thieme Verlag KG Stuttgart · New York.

The evaluation of small-sided games as a talent identification tool in highly trained prepubertal soccer players.

PubMed

Fenner, Jonathan S J; Iga, John; Unnithan, Viswanath

2016-10-01

The aim of this study was to evaluate physiological and technical attributes of prepubertal soccer players during multiple small-sided games (SSGs), and determine if SSGs can act as a talent identification tool. Sixteen highly trained U10 soccer players participated and separated into two groups of eight. Each group played six small-sided (4 vs. 4) matches of 5-min duration. Each player was awarded total points for the match result and goals scored. A game technical scoring chart was used to rate each player's performance during each game. Time-motion characteristics were measured using micromechanical devices. Total points had a very large significant relationship with game technical scoring chart (r = 0.758, P < 0.001). High-speed running distance had a significantly large correlation with game technical scoring chart (r = 0.547, P < 0.05). Total distance covered had a significant and moderate correlation with game technical scoring chart (r = 0.545, P < 0.05) and total points (r = 0.438, P < 0.05). The results demonstrated a large agreement between the highest-rated players and success in multiple SSGs, possibly due to higher-rated players covering larger distances in total and at high speed. Consequently, multiple SSG could be used to identify the more talented prepubertal soccer players.

Heart rate-based training intensity and its impact on injury incidence among elite-level professional soccer players.

PubMed

Owen, Adam L; Forsyth, Jacky J; Wong, Del P; Dellal, Alexandre; Connelly, Sean P; Chamari, Karim

2015-06-01

Elite-level professional soccer players are suggested to have increased physical, technical, tactical, and psychological capabilities when compared with their subelite counterparts. Ensuring these players remain at the elite level generally involves training many different bodily systems to a high intensity or level within a short duration. This study aimed to examine whether an increase in training volume at high-intensity levels was related to injury incidence, or increased the odds of sustaining an injury. Training intensity was monitored through time spent in high-intensity (T-HI) and very high-intensity (T-VHI) zones of 85-<90% and ≥90% of maximal heart rate (HRmax), and all injuries were recorded over 2 consecutive seasons. Twenty-three, elite professional male soccer players (mean ± SD age, 25.6 ± 4.6 years; stature, 181.8 ± 6.8 cm; and body mass, 79.3 ± 8.1 kg) were studied throughout the 2-years span of the investigation. The results showed a mean total injury incidence of 18.8 (95% confidence interval [CI], 14.7-22.9) injuries per 1,000 hours of exposure. Significant correlations were found between training volume at T-HI and injury incidence (r = 0.57, p = 0.005). Further analysis revealed how players achieving more time in the T-VHI zone during training increased the odds of sustaining a match injury (odds ratio = 1.87; 95% CI, 1.12-3.12, p = 0.02) but did not increase the odds of sustaining a training injury. Reducing the number of competitive match injuries among elite-level professional players may be possible if greater focus is placed on the training intensity and volume over a period of time ensuring the potential reduction of fatigue or overuse injuries. In addition, it is important to understand the optimal training load at which adaptation occurs without raising the risk of injury.

Prevention of non-contact anterior cruciate ligament injuries in soccer players. Part 1: Mechanisms of injury and underlying risk factors.

PubMed

Alentorn-Geli, Eduard; Myer, Gregory D; Silvers, Holly J; Samitier, Gonzalo; Romero, Daniel; Lázaro-Haro, Cristina; Cugat, Ramón

2009-07-01

Soccer is the most commonly played sport in the world, with an estimated 265 million active soccer players by 2006. Inherent to this sport is the higher risk of injury to the anterior cruciate ligament (ACL) relative to other sports. ACL injury causes the most time lost from competition in soccer which has influenced a strong research focus to determine the risk factors for injury. This research emphasis has afforded a rapid influx of literature defining potential modifiable and non-modifiable risk factors that increase the risk of injury. The purpose of the current review is to sequence the most recent literature that reports potential mechanisms and risk factors for non-contact ACL injury in soccer players. Most ACL tears in soccer players are non-contact in nature. Common playing situations precluding a non-contact ACL injury include: change of direction or cutting maneuvers combined with deceleration, landing from a jump in or near full extension, and pivoting with knee near full extension and a planted foot. The most common non-contact ACL injury mechanism include a deceleration task with high knee internal extension torque (with or without perturbation) combined with dynamic valgus rotation with the body weight shifted over the injured leg and the plantar surface of the foot fixed flat on the playing surface. Potential extrinsic non-contact ACL injury risk factors include: dry weather and surface, and artificial surface instead of natural grass. Commonly purported intrinsic risk factors include: generalized and specific knee joint laxity, small and narrow intercondylar notch width (ratio of notch width to the diameter and cross sectional area of the ACL), pre-ovulatory phase of menstrual cycle in females not using oral contraceptives, decreased relative (to quadriceps) hamstring strength and recruitment, muscular fatigue by altering neuromuscular control, decreased "core" strength and proprioception, low trunk, hip, and knee flexion angles, and high dorsiflexion of the ankle when performing sport tasks, lateral trunk displacement and hip adduction combined with increased knee abduction moments (dynamic knee valgus), and increased hip internal rotation and tibial external rotation with or without foot pronation. The identified mechanisms and risk factors for non-contact ACL injuries have been mainly studied in female soccer players; thus, further research in male players is warranted. Non-contact ACL injuries in soccer players likely has a multi-factorial etiology. The identification of those athletes at increased risk may be a salient first step before designing and implementing specific pre-season and in-season training programs aimed to modify the identified risk factors and to decrease ACL injury rates. Current evidence indicates that this crucial step to prevent ACL injury is the only option to effectively prevent the sequelae of osteoarthritis associated with this traumatic injury.

Parental influence on sport participation in elite young athletes.

PubMed

Baxter-Jones, A D G; Maffulli, N

2003-06-01

To ascertain how talented young British swimmers, gymnasts, tennis and soccer players are introduced to their sport, and to identify how they are encouraged into intensive systematic training. Two hundred and eighty-two elite young athletes (aged 8 to 17 yrs) and their parents were interviewed in their homes to identify how and why they started intensive training. Of the 4 sports studied (soccer, gymnastics, tennis, and swimming), parents of swimmers were more likely introduce their children to the sport (70%), while parents of gymnasts (42%) were the least likely to do so. However, in this sports parents played a lesser role in the transition to intensive training (6% and 5%, respectively). Nearly half the soccer players (47%) became involved in the sport because of their own interest, with the majority making the transition to intensive training because of encouragement by a coach (65%). Self-motivation (27%) and parental influence (57%) brought children into tennis with 25% of the young athletes in the sample autonomously deciding to start intensive training. Children from the lower socio-economic classes were underrepresented, and the total number of 1-parent families (5.3%) was considerably less than current British national norms (16.1%). In Britain, young athletes' involvement in high level sport is heavily dependent on their parents, with sports clubs and coaches playing an important later role. In the present socio-economic and cultural situation, many talented youngsters with less motivated parents will not undertake sport. Talented youngsters from a poorer economic background will be heavily disadvantaged, especially in sports such as tennis.

Bone properties in child and adolescent male hockey and soccer players.

PubMed

Falk, Bareket; Braid, Sarah; Moore, Michael; Yao, Matthew; Sullivan, Phil; Klentrou, Nota

2010-07-01

Children and adolescents who train extensively in high-impact, weight-bearing activities have enhanced bone mineral density. The purpose of this study was to evaluate bone strength, as reflected by quantitative ultrasound (QUS, Sunlight Omniscence), of child (10-12 yrs old) and adolescent (14-16 yrs old) male soccer and hockey players in comparison with age-matched controls. The groups included 30 child (CH) and 31 adolescent (AH) hockey players, 26 child (CS) and 30 adolescent (AS) soccer players, as well as 34 child (CC) and 31 adolescent (AC) healthy, non-athletic, age-matched controls. All athletes trained at an elite level year-round, with no difference in training volume between groups. Ultrasound speed of sound (SOS) was measured at the distal-radius and mid-tibia. In both age groups, hockey players were the heaviest and had the highest fat-free mass. No differences were found among groups in total energy intake, calcium or vitamin D intake. Radial and tibial SOS increased with age. Hockey players had higher radial SOS in both age groups (children: CH:3763+/-74, CS:3736+/-77, CC:3721+/-88 m/s; adolescents: AH:3809+/-105, AS:3767+/-85, AC:3760+/-94 m/s). Tibial SOS was higher in soccer players compared with controls. In spite of the higher body mass and fat-free mass in hockey players, their tibial SOS was similar to the non-athletes in both age groups. These findings support previous suggestions of sport-specific effects on bone strength. However, they need to be corroborated with longitudinal or prospective intervention studies. Copyright 2009 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Fascicle arrangements of vastus lateralis and gastrocnemius muscles in highly trained soccer players and swimmers of both genders.

PubMed

Kanehisa, H; Muraoka, Y; Kawakami, Y; Fukunaga, T

2003-02-01

The thickness, fascicle angles of pennation, and fascicle length of the vastus lateralis (VL) and medial gastrocnemius (MG) muscles in highly trained soccer players and swimmers of both genders were determined from ulrasonograms to investigate whether the fascicle arrangements of the lower limb muscles in the athletes could be related to the requirements of the events, i. e., intensive muscular activities in the water versus on the ground. In comparisons between the two events, the soccer players tended to show shorter fascicles and greater fascicle angles, and the swimmers thicker muscles and longer fascicles, especially in VL. In both events, the males showed thicker muscles and greater fascicle angles than the females. In both VL and MG, the thickness, fascicle length and fascicle angle were related to each other in a right-angled triangle model, and so, most of the event- and/or gender-related differences observed in the fascicle angle depended on the difference in muscle thickness relative to fascicle length. The present data cannot answer the question of whether the athletes had muscles suited to their respective sports prior to beginning their sports or whether the muscles adapted specifically to the competitive and/or training styles. However, it might be assumed that the lower limb muscles for swimmers are suitable to perform rapid, powerful kick movements during competitive swims by having greater thickness and longer fascicle, i. e., priorities in both force production and shortening velocity, but those for soccer players do not show architectural profiles which can be related to intensive activity on the ground, except that the thickness values exceed the normal range.

Assessment of Energy Intake and Energy Expenditure of Male Adolescent Academy-Level Soccer Players during a Competitive Week.

PubMed

Briggs, Marc A; Cockburn, Emma; Rumbold, Penny L S; Rae, Glen; Stevenson, Emma J; Russell, Mark

2015-10-02

This study investigated the energy intake and expenditure of professional adolescent academy-level soccer players during a competitive week. Over a seven day period that included four training days, two rest days and a match day, energy intake (self-reported weighed food diary and 24-h recall) and expenditure (tri-axial accelerometry) were recorded in 10 male players from a professional English Premier League club. The mean macronutrient composition of the dietary intake was 318 ± 24 g·day(-1) (5.6 ± 0.4 g·kg(-1) BM) carbohydrate, 86 ± 10 g·day(-1) (1.5 ± 0.2 g·kg(-1) BM) protein and 70 ± 7 g·day(-1) (1.2 ± 0.1 g·kg(-1) BM) fats, representing 55% ± 3%, 16% ± 1%, and 29% ± 2% of mean daily energy intake respectively. A mean daily energy deficit of -1302 ± 1662 kJ (p = 0.035) was observed between energy intake (9395 ± 1344 kJ) and energy expenditure (10679 ± 1026 kJ). Match days (-2278 ± 2307 kJ, p = 0.012) and heavy training days (-2114 ± 2257 kJ, p = 0.016) elicited the greatest deficits between intake and expenditure. In conclusion, the mean daily energy intake of professional adolescent academy-level soccer players was lower than the energy expended during a competitive week. The magnitudes of these deficits were greatest on match and heavy training days. These findings may have both short and long term implications on the performance and physical development of adolescent soccer players.

Beetroot Juice Supplementation Improves High-Intensity Intermittent Type Exercise Performance in Trained Soccer Players.

PubMed

Nyakayiru, Jean; Jonvik, Kristin L; Trommelen, Jorn; Pinckaers, Philippe J M; Senden, Joan M; van Loon, Luc J C; Verdijk, Lex B

2017-03-22

It has been shown that nitrate supplementation can enhance endurance exercise performance. Recent work suggests that nitrate ingestion can also increase intermittent type exercise performance in recreational athletes. We hypothesized that six days of nitrate supplementation can improve high-intensity intermittent type exercise performance in trained soccer players. Thirty-two male soccer players (age: 23 ± 1 years, height: 181 ± 1 m, weight: 77 ± 1 kg, playing experience: 15.2 ± 0.5 years, playing in the first team of a 2nd or 3rd Dutch amateur league club) participated in this randomized, double-blind cross-over study. All subjects participated in two test days in which high-intensity intermittent running performance was assessed using the Yo-Yo IR1 test. Subjects ingested nitrate-rich (140 mL; ~800 mg nitrate/day; BR) or a nitrate-depleted beetroot juice (PLA) for six subsequent days, with at least eight days of wash-out between trials. The distance covered during the Yo-Yo IR1 was the primary outcome measure, while heart rate (HR) was measured continuously throughout the test, and a single blood and saliva sample were collected just prior to the test. Six days of BR ingestion increased plasma and salivary nitrate and nitrite concentrations in comparison to PLA ( p < 0.001), and enhanced Yo-Yo IR1 test performance by 3.4 ± 1.3% (from 1574 ± 47 to 1623 ± 48 m; p = 0.027). Mean HR was lower in the BR (172 ± 2) vs. PLA trial (175 ± 2; p = 0.014). Six days of BR ingestion effectively improves high-intensity intermittent type exercise performance in trained soccer players.

Beetroot Juice Supplementation Improves High-Intensity Intermittent Type Exercise Performance in Trained Soccer Players

PubMed Central

Nyakayiru, Jean; Jonvik, Kristin L.; Trommelen, Jorn; Pinckaers, Philippe J. M.; Senden, Joan M.; van Loon, Luc J. C.; Verdijk, Lex B.

2017-01-01

It has been shown that nitrate supplementation can enhance endurance exercise performance. Recent work suggests that nitrate ingestion can also increase intermittent type exercise performance in recreational athletes. We hypothesized that six days of nitrate supplementation can improve high-intensity intermittent type exercise performance in trained soccer players. Thirty-two male soccer players (age: 23 ± 1 years, height: 181 ± 1 m, weight: 77 ± 1 kg, playing experience: 15.2 ± 0.5 years, playing in the first team of a 2nd or 3rd Dutch amateur league club) participated in this randomized, double-blind cross-over study. All subjects participated in two test days in which high-intensity intermittent running performance was assessed using the Yo-Yo IR1 test. Subjects ingested nitrate-rich (140 mL; ~800 mg nitrate/day; BR) or a nitrate-depleted beetroot juice (PLA) for six subsequent days, with at least eight days of wash-out between trials. The distance covered during the Yo-Yo IR1 was the primary outcome measure, while heart rate (HR) was measured continuously throughout the test, and a single blood and saliva sample were collected just prior to the test. Six days of BR ingestion increased plasma and salivary nitrate and nitrite concentrations in comparison to PLA (p < 0.001), and enhanced Yo-Yo IR1 test performance by 3.4 ± 1.3% (from 1574 ± 47 to 1623 ± 48 m; p = 0.027). Mean HR was lower in the BR (172 ± 2) vs. PLA trial (175 ± 2; p = 0.014). Six days of BR ingestion effectively improves high-intensity intermittent type exercise performance in trained soccer players. PMID:28327503

Assessment of Energy Intake and Energy Expenditure of Male Adolescent Academy-Level Soccer Players during a Competitive Week

PubMed Central

Briggs, Marc A.; Cockburn, Emma; Rumbold, Penny L. S.; Rae, Glen; Stevenson, Emma J.; Russell, Mark

2015-01-01

This study investigated the energy intake and expenditure of professional adolescent academy-level soccer players during a competitive week. Over a seven day period that included four training days, two rest days and a match day, energy intake (self-reported weighed food diary and 24-h recall) and expenditure (tri-axial accelerometry) were recorded in 10 male players from a professional English Premier League club. The mean macronutrient composition of the dietary intake was 318 ± 24 g·day−1 (5.6 ± 0.4 g·kg−1 BM) carbohydrate, 86 ± 10 g·day−1 (1.5 ± 0.2 g·kg−1 BM) protein and 70 ± 7 g·day−1 (1.2 ± 0.1 g·kg−1 BM) fats, representing 55% ± 3%, 16% ± 1%, and 29% ± 2% of mean daily energy intake respectively. A mean daily energy deficit of −1302 ± 1662 kJ (p = 0.035) was observed between energy intake (9395 ± 1344 kJ) and energy expenditure (10679 ± 1026 kJ). Match days (−2278 ± 2307 kJ, p = 0.012) and heavy training days (−2114 ± 2257 kJ, p = 0.016) elicited the greatest deficits between intake and expenditure. In conclusion, the mean daily energy intake of professional adolescent academy-level soccer players was lower than the energy expended during a competitive week. The magnitudes of these deficits were greatest on match and heavy training days. These findings may have both short and long term implications on the performance and physical development of adolescent soccer players. PMID:26445059

Left ventricular remodeling and the athlete's heart, irrespective of quality load training.

PubMed

Galanti, Giorgio; Stefani, Laura; Mascherini, Gabriele; Di Tante, Valentina; Toncelli, Loira

2016-11-17

Regular physical exercise determines a progressive increase of the cardiac mass known as adaptive hypertrophy. Up to now, two morphological echocardiographic heart patterns of athletes have been described by Morganroth in 1975: predominant augmentation of wall thickness, and major cavity size in chamber dimensions in the case of prevalent static or dynamic components. The aim of the study was to follow up the impact of physical training on heart morphology and function in a group of elite soccer and rugby players for at least five years. From January 1993 to December 2015 a group of 250 elite soccer players and 114 rugby players were examined: 78 soccer players and 60 rugby players were followed up for 5 years. They were matched with a control group. LV dimensions and LVMi were significantly higher in the athletes than in the inactive subjects (LVMi : 123.45; LVMi: 81.5 vs 94.36 g/m2 respectively). After the five-year follow up the athletes showed no significant modifications in cardiac dimensions: (LVDd from 52.00 ± mm to 52.90 ± mm; LVSd increased from 31.58 ± mm to 32.33 ± mm; Left Ventricular CMI from 120.77 to 121.45 g/m2;p = NS in soccer; from 50.43 ± mm to 52.22 ± mm; Left Ventricular Systolic diameter increased from 32.51 ± mm to 32.8 ± mm; Left Ventricular Mass index from 81,5 to 87,4 g/m2;p = NS and no significant enhancement of the aortic root diameter was observed (Aortic root: from 27.39 mm to 31.64 mm in soccer players; from 30,68 mm to 30.95 mm). No significant differences were found among the athletes practicing sports with different workload components, and resistance training. In trained athletes the dimensions of the LV chamber and LVMi are generally within the upper limits of the normal range. After a five-year follow-up, the dimensions of the chambers of the heart remain within the normal range, despite being within the the upper limits. Regular physical exercise induces mild LV hypertrophy which therefore can be considered an adaptive consequence to stress-exercise.

Modulation of Isometric Quadriceps Strength in Soccer Players With Transcranial Direct Current Stimulation: A Crossover Study.

PubMed

Vargas, Valentine Z; Baptista, Abrahão F; Pereira, Guilherme O C; Pochini, Alberto C; Ejnisman, Benno; Santos, Marcelo B; João, Silvia M A; Hazime, Fuad A

2018-05-01

Vargas, VZ, Baptista, AF, Pereira, GOC, Pochini, AC, Ejnisman, B, Santos, MB, João, SMA, and Hazime, FA. Modulation of isometric quadriceps strength in soccer players with transcranial direct current stimulation: a crossover study. J Strength Cond Res 32(5): 1336-1341, 2018-The aim of this study was to evaluate the effect of transcranial direct current stimulation (tDCS) on the maximum isometric muscle contraction (MVIC) of the knee extensors in soccer players at the preprofessional level. Twenty female soccer players aged 15-17 years (mean = 16.1; SD = 0.9) with 5.2 ± 2.6 years of training were randomly divided into 2 groups to receive either active or sham tDCS in a single session (2 mA; 0.057 mA·cm). The MVIC of the knee extensors was evaluated in both lower limbs by manual dynamometry in 5 sets of contractions divided into 4 blocks: (a) prestimulation, (b) during tDCS, (c) 30 minutes after tDCS, and (d) 60 minutes after tDCS. After an interval of 7 days, the groups were evaluated again, and the type of initial stimulation was inverted between participants. The MVIC of the knee extensors increased significantly during active tDCS (dominant limb (DL) = 0.4; IC = 0.1-0.8 N·Kg), 30 minutes after active tDCS (DL = 0.9; IC 0.4-1.4 N·Kg), and 60 minutes after active tDCS (DL = 1.0; IC 0.3-1.6 N·Kg) but not for sham tDCS. Our conclusion was that tDCS temporarily increases isometric quadriceps strength in adolescent female soccer players, which may be useful for both strength training and rehabilitation.

The effect of high vs. low carbohydrate diets on distances covered in soccer.

PubMed

Souglis, Athanasios G; Chryssanthopoulos, Costas I; Travlos, Antonios K; Zorzou, Amalia E; Gissis, Ioannis T; Papadopoulos, Christos N; Sotiropoulos, Aristomenis A

2013-08-01

The purpose of this study was to compare the distances covered during a 11-a-side soccer match after players had consumed either a high carbohydrate (CHO) or a low CHO diet. Twenty-two male professional soccer players formed 2 teams (A and B), of similar age, body characteristics, and training experience. The 2 teams played against each other twice with a week interval between. For 3.5 days before the first match, the players of team A followed a high CHO diet that provided 8 g CHO per kg body mass (BM) (HC), whereas team B players followed a low CHO diet that provided 3 g CHO per kg BM (LC) for the same time period. Before the second match the dietary treatment was reversed and followed for the same time period. Training during the study was controlled, and distances covered were measured using global positioning system technology. Every player covered a greater total distance in HC compared with the distance covered in LC (HC: 9,380 ± 98 m vs. LC: 8,077 ± 109 m; p < 0.01). All distances covered from easy jogging (7.15 km·h-1) to sprinting (24.15 km·h-1) were also higher in HC compared with LC (p < 0.01). When players followed the HC treatment, they won the match (team A vs. team B: 3-1 for the first game and 1-2 for the second game). The HC diet probably helped players to cover a greater distance compared with LC. Soccer players should avoid eating a low (3 g CHO per kg BM) CHO diet 3-4 days before an important soccer match and have a high CHO intake that provides at least 8 g CHO per kg BM.

Mental Fatigue Impairs Soccer-Specific Physical and Technical Performance.

PubMed

Smith, Mitchell R; Coutts, Aaron J; Merlini, Michele; Deprez, Dieter; Lenoir, Matthieu; Marcora, Samuele M

2016-02-01

To investigate the effects of mental fatigue on soccer-specific physical and technical performance. This investigation consisted of two separate studies. Study 1 assessed the soccer-specific physical performance of 12 moderately trained soccer players using the Yo-Yo Intermittent Recovery Test, Level 1 (Yo-Yo IR1). Study 2 assessed the soccer-specific technical performance of 14 experienced soccer players using the Loughborough Soccer Passing and Shooting Tests (LSPT, LSST). Each test was performed on two occasions and preceded, in a randomized, counterbalanced order, by 30 min of the Stroop task (mentally fatiguing treatment) or 30 min of reading magazines (control treatment). Subjective ratings of mental fatigue were measured before and after treatment, and mental effort and motivation were measured after treatment. Distance run, heart rate, and ratings of perceived exertion were recorded during the Yo-Yo IR1. LSPT performance time was calculated as original time plus penalty time. LSST performance was assessed using shot speed, shot accuracy, and shot sequence time. Subjective ratings of mental fatigue and effort were higher after the Stroop task in both studies (P < 0.001), whereas motivation was similar between conditions. This mental fatigue significantly reduced running distance in the Yo-Yo IR1 (P < 0.001). No difference in heart rate existed between conditions, whereas ratings of perceived exertion were significantly higher at iso-time in the mental fatigue condition (P < 0.01). LSPT original time and performance time were not different between conditions; however, penalty time significantly increased in the mental fatigue condition (P = 0.015). Mental fatigue also impaired shot speed (P = 0.024) and accuracy (P < 0.01), whereas shot sequence time was similar between conditions. Mental fatigue impairs soccer-specific running, passing, and shooting performance.

The delivery of injury prevention exercise programmes in professional youth soccer: Comparison to the FIFA 11.

PubMed

O'Brien, James; Young, Warren; Finch, Caroline F

2017-01-01

Injury prevention exercise programmes for amateur soccer have gained considerable attention, but little is known about their relevance and adaptability to professional soccer settings. The first aim of this study was to evaluate the delivery and content of injury prevention exercise programmes used by professional youth soccer teams, compared to the industry standard injury prevention exercise programme for soccer, the Fédération Internationale de Football Association's FIFA 11+. The second aim was to document specific challenges to implementing injury prevention exercise programmes in this context. Prospective observational study. The participants were soccer coaches, fitness coaches and physiotherapists (n=18) from four teams in a professional youth soccer academy. Each team's chosen injury prevention exercise programmes were observed weekly across an entire soccer season (160 sessions). The delivery and content of the programmes were documented on a standardised worksheet and compared to the FIFA 11+. Specific implementation challenges were recorded. Fitness coaches were the primary deliverers of injury prevention exercise programmes, with support from physiotherapists. Multiple delivery formats and locations were employed, along with the extensive use of equipment. Across all injury prevention exercise programme sessions, a median of one FIFA 11+ exercise was performed in its original form and a further four in a modified form. Implementation challenges included poor staff communication, competing training priorities and heavy game schedules. Although the basic components of the FIFA 11+ hold relevance for professional youth male teams, the delivery and content of injury prevention exercise programmes require considerable tailoring for this context. Recognising this will inform the development of improved, context-specific injury prevention exercise programmes, along with corresponding strategies to enhance their implementation. Copyright © 2016 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Copenhagen hip and groin outcome score (HAGOS) in male soccer: reference values for hip and groin injury-free players.

PubMed

Thorborg, Kristian; Branci, Sonia; Stensbirk, Frederik; Jensen, Jesper; Hölmich, Per

2014-04-01

Reference values are needed in order to interpret the Copenhagen Hip and Groin Outcome Score (HAGOS) in male soccer players with hip and groin pain. The aim of this study was to establish reference values for HAGOS in hip and groin injury-free male soccer players. We included 444 groin injury-free soccer players from 40 clubs (divisions 1-4) in Eastern Denmark, mean age (SD) 23.6 (4.4), training soccer 3.4 (1) times per week. All players were hip and groin injury-free at the time of inclusion (beginning of season, 2011). Of the 444 hip and groin injury-free players, 301 reported no hip and/or groin pain in either the present or the previous season, and 143 reported that they had experienced hip and/or groin pain in the previous season. Players (n=143) with hip and groin pain in the previous season displayed lower scores than players without (n=301), for all HAGOS subscales (p<0.001). Age and playing level were not related to HAGOS. The 95% reference ranges for HAGOS subscales in hip and groin injury-free soccer players, with no pain in the previous or present season (n=301), are: pain: 80.1-100, symptoms: 64.3-100, activities of daily living: 80.3-100, sport and recreational activities: 71.9-100, participation in physical activity: 75-100 and quality of living: 75-100. Lower HAGOS subscales are seen in soccer players who have experienced hip and/or groin pain in the previous season, compared with those who have not. Median HAGOS subscale scores in hip and groin injury-free soccer players are in proximity to the maximum score (100 points).

Specific Adaptations in Performance and Muscle Architecture After Weighted Jump-Squat vs. Body Mass Squat Jump Training in Recreational Soccer Players.

PubMed

Coratella, Giuseppe; Beato, Marco; Milanese, Chiara; Longo, Stefano; Limonta, Eloisa; Rampichini, Susanna; Cè, Emiliano; Bisconti, Angela V; Schena, Federico; Esposito, Fabio

2018-04-01

Coratella, G, Beato, M, Milanese, C, Longo, S, Limonta, E, Rampichini, S, Cè, E, Bisconti, AV, Schena, F, and Esposito, F. Specific adaptations in performance and muscle architecture after weighted jump-squat vs. body mass squat jump training in recreational soccer players. J Strength Cond Res 32(4): 921-929, 2018-The aim of the present study was to compare the effects of weighted jump-squat training (WJST) vs. body mass squat jump training (BMSJT) on quadriceps' muscle architecture, lower-limb lean-mass (LM) and muscle strength, performance in change of direction (COD), and sprint and jump in recreational soccer players. Forty-eight healthy soccer players participated in an offseason randomized controlled trial. Before and after an 8-week training intervention, vastus lateralis pennation angle, fascicle length, muscle thickness, LM, squat 1RM, quadriceps and hamstrings isokinetic peak torque, agility T-test, 10-and 30-m sprints, and squat-jump (SJ) were measured. Although similar increases were observed in muscle thickness, fascicle length increased more in WJST (Effect size [ES] = 1.18, 0.82-1.54) than in BMSJT (ES = 0.54, 0.40-0.68), and pennation angle increased only in BMSJT (ES = 1.03, 0.78-1.29). Greater increases in LM were observed in WJST (ES = 0.44, 0.29-0.59) than in BMSJT (ES = 0.21, 0.07-0.37). The agility T-test (ES = 2.95, 2.72-3.18), 10-m (ES = 0.52, 0.22-0.82), and 30-m sprints (ES = 0.52, 0.23-0.81) improved only in WJST, whereas SJ improved in BMSJT (ES = 0.89, 0.43-1.35) more than in WJST (ES = 0.30, 0.03-0.58). Similar increases in squat 1RM and peak torque occurred in both groups. The greater inertia accumulated within the landing phase in WJST vs. BMSJT has increased the eccentric workload, leading to specific eccentric-like adaptations in muscle architecture. The selective improvements in COD in WJST may be related to the increased braking ability generated by the enhanced eccentric workload.

Allometric multilevel modelling of agility and dribbling speed by skeletal age and playing position in youth soccer players.

PubMed

Valente-dos-Santos, J; Coelho-e-Silva, M J; Duarte, J; Pereira, J; Rebelo-Gonçalves, R; Figueiredo, A; Mazzuco, M A; Sherar, L B; Elferink-Gemser, M T; Malina, R M

2014-08-01

This study evaluates the contributions of age, skeletal maturation, body size and composition, training and playing position to the development of agility and dribbling speed in young male soccer players (10-18 years) followed longitudinally. 83 players [defenders (n=35), midfielders (n=27), forwards (n=21)] were followed annually over 5 years (average: 4.4 observations per player). Skeletal age (SA), stature, body mass, triceps and subscapular skinfolds, agility and dribbling speed were measured annually. Body composition was estimated from the 2 skinfolds. Annual training volume was estimated from weekly participation forms completed by coaches. The multiplicative allometric models with the best statistical fit showed that statural growth of 1 cm predicts 1.334 s and 1.927 s of improvement in agility and dribbling speed, respectively. Significant independent effects of fat-free mass and annual volume training were found for agility and dribbling speed, respectively (P<0.05). Predicted agility (from 12 to 18 years of SA) and dribbling speed (from 13 to 18 years of SA) differed significantly among players by playing positions (midfielders>forwards>defenders). The present results provide developmental models for the interpretation of intra- and inter-individual variability in agility and dribbling speed among youth soccer players across adolescence, and may provide a framework for trainers and coaches to develop and evaluate individualized training protocols. © Georg Thieme Verlag KG Stuttgart · New York.

A comparison of methods to quantify the in-season training load of professional soccer players.

PubMed

Scott, Brendan R; Lockie, Robert G; Knight, Timothy J; Clark, Andrew C; Janse de Jonge, Xanne A K

2013-03-01

To compare various measures of training load (TL) derived from physiological (heart rate [HR]), perceptual (rating of perceived exertion [RPE]), and physical (global positioning system [GPS] and accelerometer) data during in-season field-based training for professional soccer. Fifteen professional male soccer players (age 24.9 ± 5.4 y, body mass 77.6 ± 7.5 kg, height 181.1 ± 6.9 cm) were assessed in-season across 97 individual training sessions. Measures of external TL (total distance [TD], the volume of low-speed activity [LSA; <14.4 km/h], high-speed running [HSR; >14.4 km/h], very high-speed running [VHSR; >19.8 km/h], and player load), HR and session-RPE (sRPE) scores were recorded. Internal TL scores (HR-based and sRPE-based) were calculated, and their relationships with measures of external TL were quantified using Pearson product-moment correlations. Physical measures of TD, LSA volume, and player load provided large, significant (r = .71-.84; P < .01) correlations with the HR-based and sRPE-based methods. Volume of HSR and VHSR provided moderate to large, significant (r = .40-.67; P < .01) correlations with measures of internal TL. While the volume of HSR and VHSR provided significant relationships with internal TL, physical-performance measures of TD, LSA volume, and player load appear to be more acceptable indicators of external TL, due to the greater magnitude of their correlations with measures of internal TL.

Soccer and sexual health education: a promising approach for reducing adolescent births in Haiti.

PubMed

Kaplan, Kathryn C; Lewis, Judy; Gebrian, Bette; Theall, Katherine

2015-05-01

To explore the effect of an innovative, integrative program in female sexual reproductive health (SRH) and soccer (or fútbol, in Haitian Creole) in rural Haiti by measuring the rate of births among program participants 15-19 years old and their nonparticipant peers. A retrospective cohort study using 2006-2009 data from the computerized data-tracking system of the Haitian Health Foundation (HHF), a U.S.-based nongovernmental organization serving urban and rural populations in Haiti, was used to assess births among girls 15-19 years old who participated in HHF's GenNext program, a combination education-soccer program for youth, based on SRH classes HHF nurses and community workers had been conducting in Haiti for mothers, fathers, and youth; girl-centered health screenings; and an all-female summer soccer league, during 2006-2009 (n = 4 251). Bivariate and multiple logistic regression analyses were carried out to assess differences in the rate of births among program participants according to their level of participation (SRH component only ("EDU") versus both the SRH and soccer components ("SO") compared to their village peers who did not participate. Hazard ratios (HRs) of birth rates were estimated using Cox regression analysis of childbearing data for the three different groups. In the multiple logistic regression analysis, only the girls in the "EDU" group had significantly fewer births than the nonparticipants after adjusting for confounders (odds ratio = 0.535; 95% confidence interval (CI) = 0.304, 0.940). The Cox regression analysis demonstrated that those in the EDU group (HR = 0.893; 95% CI = 0.802, 0.994) and to a greater degree those in the SO group (HR = 0.631; 95% CI = 0.558, 0.714) were significantly protected against childbearing between the ages of 15 and 19 years. HHF's GenNext program demonstrates the effectiveness of utilizing nurse educators, community mobilization, and youth participation in sports, education, and structured youth groups to promote and sustain health for adolescent girls and young women.

Specific physical trainability in elite young soccer players: efficiency over 6 weeks’ in-season training

PubMed Central

Rouissi, M; Haddad, M; Chtara, H; Chaalali, A; Owen, A; Chamari, K

2017-01-01

The aim of the present study was to compare the effects of 3 training protocols (plyometric [PLYO], agility [AG], or repeated shuttle sprints [RS]) on physical performance in the same population of young soccer players. Forty-two youth-level male players (13.6±0.3-years; 1.65±0.07 m; 54.1±6.5 kg; body fat: 12.8±2.6%) participated in a short-term (6-week) randomized parallel fully controlled training study (pre-to-post measurements): PLYO group, n=10; AG group, n=10; RS group, n=12; and control group [CON] n=10. PLYO training = 9 lower limb exercises (2-3 sets of 8-12 repetitions). The AG group performed planned AG drills and direction changes. RS training consisted of 2-4 sets of 5-6x 20 to 30 m shuttle sprints (20 seconds recovery in between). Progressive overload principles were incorporated into the programme by increasing the number of foot contacts and varying the complexity of the exercises. Pre/post-training tests were: bilateral standing horizontal jump, and unilateral horizontal jumps, sprint (30 m with 10 m lap time), agility (20 m zigzag), and repeated sprint ability (RSA) (i.e. 6x30 m shuttle sprints: 2x15 m with 180° turns). Significant main effects for time (i.e. training application) and group (training type) were detected. Improvements in horizontal jumping were higher (p<0.01: ES=large) in PLYO. The RS group improved significantly more (p<0.01; ES=large) than other groups: 30 m sprint, RSAbest and RSAmean performances. Significantly greater increases in 20 m zigzag performance were observed following AG and RS training (4.0 and 3.8%, respectively) compared with PLYO (2.0%) and CON training (0.8%). No significant differences were reported in the RSAdec between groups. Elite young male soccer players’ physical performances can be significantly and specifically improved either using PLYO or AG or RSA training over short-term in-season training. PMID:28566807

Specific physical trainability in elite young soccer players: efficiency over 6 weeks' in-season training.

PubMed

Chtara, M; Rouissi, M; Haddad, M; Chtara, H; Chaalali, A; Owen, A; Chamari, K

2017-06-01

The aim of the present study was to compare the effects of 3 training protocols (plyometric [PLYO], agility [AG], or repeated shuttle sprints [RS]) on physical performance in the same population of young soccer players. Forty-two youth-level male players (13.6±0.3-years; 1.65±0.07 m; 54.1±6.5 kg; body fat: 12.8±2.6%) participated in a short-term (6-week) randomized parallel fully controlled training study (pre-to-post measurements): PLYO group, n=10; AG group, n=10; RS group, n=12; and control group [CON] n=10. PLYO training = 9 lower limb exercises (2-3 sets of 8-12 repetitions). The AG group performed planned AG drills and direction changes. RS training consisted of 2-4 sets of 5-6x 20 to 30 m shuttle sprints (20 seconds recovery in between). Progressive overload principles were incorporated into the programme by increasing the number of foot contacts and varying the complexity of the exercises. Pre/post-training tests were: bilateral standing horizontal jump, and unilateral horizontal jumps, sprint (30 m with 10 m lap time), agility (20 m zigzag), and repeated sprint ability (RSA) (i.e. 6x30 m shuttle sprints: 2x15 m with 180° turns). Significant main effects for time (i.e. training application) and group (training type) were detected. Improvements in horizontal jumping were higher (p<0.01: ES=large) in PLYO. The RS group improved significantly more (p<0.01; ES=large) than other groups: 30 m sprint, RSA best and RSA mean performances. Significantly greater increases in 20 m zigzag performance were observed following AG and RS training (4.0 and 3.8%, respectively) compared with PLYO (2.0%) and CON training (0.8%). No significant differences were reported in the RSA dec between groups. Elite young male soccer players' physical performances can be significantly and specifically improved either using PLYO or AG or RSA training over short-term in-season training.

The Effects of Continuous One-Arm Kettlebell Swing Training on Physiological Parameters in United States Air Force Personnel: A Pilot Study

DTIC Science & Technology

2016-11-01

collegiate soccer players . KB snatches were performed 3 days per week for 20 minutes with 15-second work-to-rest intervals, while the control group...10] used KB weights that were 18% of total body mass and reported a 6% improvement in aerobic capacity in women’s collegiate soccer players who...Force Personnel: A Pilot Study Molly Wade, MS; Reginald O’Hara, PhD; Lydia Caldwell, MS; Jason Ordway, MS; Darryn Bryant, MS

Match analysis of U9 and U10 english premier league academy soccer players using a global positioning system: relevance for talent identification and development.

PubMed

Goto, Heita; Morris, John G; Nevill, Mary E

2015-04-01

The purpose of this study was to examine the match activity profile of U9 and U10 elite soccer players and to establish if there were any differences between players who were subsequently retained or released by their clubs. Such information should prove valuable in the design of training programs for these very young players and in the talent identification and development process. A Global Positioning System was used to analyze 2-4 interacademy 6-a-side matches of English Premier League Academy players (U9: N = 22 and U10: N = 12) who trained 3 times a week (4.5 hours). Speed zones were created based on 5 and 10-m sprint times, and an independent sample t-test was employed for a statistical analysis. Both squads covered ∼4,000 m in total or ∼4,700 m·h during a match (p = NS between squads), with the U10 squad tending to cover a greater distance at moderate (p = 0.10) and high speeds (p = 0.08) than the U9 squad. Retained group covered a greater distance than released group (retained vs. released: 4,478 ± 513 m vs. 4,091 ± 462 m, p < 0.05) during a match and covered a greater distance during low-speed running in absolute (1,226 ± 259 m vs. 1,005 ± 221 m, p < 0.05) and relative (1,325 ± 235 m·h vs. 1,132 ± 210 m·h, p < 0.05) terms. Thus, U9 and U10 players cover over 4000 m in match play, and those players who are retained by academies cover a greater distance in total and at low speeds (2.1-3.1 m·s). This information may support the preparation of squad training programs and the talent identification and development process.

Community participatory physical activity intervention targets children at high risk for obesity

USDA-ARS?s Scientific Manuscript database

This community participatory research evaluated the feasibility of a summer soccer and nutrition education program to increase physical activity (PA) in rural Mississippi Delta children at high risk of obesity and previously not exposed to soccer. Children aged 4-12 were recruited through school and...

The effects of concussion legislation one year later--what have we learned: a descriptive pilot survey of youth soccer player associates.

PubMed

Shenouda, Christian; Hendrickson, Peter; Davenport, Kathleen; Barber, Jason; Bell, Kathleen R

2012-06-01

To assess the knowledge of youth soccer athletes' parents, coaches, and soccer officials regarding concussion and return-to-play guidelines contained in the Lystedt Law in Washington State. Survey study. Surveys were distributed via the youth soccer association monthly electronic newsletter in September and October 2010. Links to the survey also were provided via the Washington Youth Soccer Facebook page and Twitter feed. Respondents were 18 years or older and were associated with Washington Youth Soccer. The percentage of correct responses to questions regarding the identification and management of concussion symptoms and return to play guidelines as outlined in the Lystedt Law. A total of 391 adults responded; 63% were exclusively parents, 20% were coaches, and 17% were noncoaches (eg, club officers, referees, or volunteers). A total of 96% knew that concussions were a type of traumatic brain injury, 93% identified concussions as serious, and 93% knew that loss of consciousness is not universal. From the responses, 98% identified neurological manifestations of concussions, 90% chose to delay return to play in the presence of neurological symptoms, 85% were aware of the Lystedt Law, and only 73% knew that players must receive written clearance to return to play. A total of 88% were aware that a parent or legal guardian was not allowed to clear an athlete to return to play if a trained professional was not available. Survey respondents were less sure of soccer association guidelines for reporting medical clearance to club officials. These data suggest that, although general knowledge of parents, coaches, and referees in youth soccer in Washington State is high, gaps in knowledge and practice regarding the prevention of concussion in youth soccer athletes still exist. Copyright © 2012 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

Importance of Reactive Agility and Change of Direction Speed in Differentiating Performance Levels in Junior Soccer Players: Reliability and Validity of Newly Developed Soccer-Specific Tests

PubMed Central

Pojskic, Haris; Åslin, Erik; Krolo, Ante; Jukic, Ivan; Uljevic, Ognjen; Spasic, Miodrag; Sekulic, Damir

2018-01-01

Agility is a significant determinant of success in soccer; however, studies have rarely presented and evaluated soccer-specific tests of reactive agility (S_RAG) and non-reactive agility (change of direction speed – S_CODS) or their applicability in this sport. The aim of this study was to define the reliability and validity of newly developed tests of the S_RAG and S_CODS to discriminate between the performance levels of junior soccer players. The study consisted of 20 players who were involved at the highest national competitive rank (all males; age: 17.0 ± 0.9 years), divided into three playing positions (defenders, midfielders, and forwards) and two performance levels (U17 and U19). Variables included body mass (BM), body height, body fat percentage, 20-m sprint, squat jump, countermovement jump, reactive-strength-index, unilateral jump, 1RM-back-squat, S_CODS, and three protocols of S_RAG. The reliabilities of the S_RAG and S_CODS were appropriate to high (ICC: 0.70 to 0.92), with the strongest reliability evidenced for the S_CODS. The S_CODS and S_RAG shared 25–40% of the common variance. Playing positions significantly differed in BM (large effect-size differences [ES]; midfielders were lightest) and 1RM-back-squat (large ES; lowest results in midfielders). The performance levels significantly differed in age and experience in soccer; U19 achieved better results in the S_CODS (t-test: 3.61, p < 0.05, large ES) and two S_RAG protocols (t-test: 2.14 and 2.41, p < 0.05, moderate ES). Newly developed tests of soccer-specific agility are applicable to differentiate U17 and U19 players. Coaches who work with young soccer athletes should be informed that the development of soccer-specific CODS and RAG in this age is mostly dependent on training of the specific motor proficiency. PMID:29867552

Testing of tactical performance in youth elite soccer.

PubMed

Memmert, Daniel

2010-01-01

This is a twofold study with the goals of evaluating tactical oriented game test situations for 12-13-year old highly-talented soccer players and to analyze dynamic, intra-individual developments of the players. A cross-sectional design was carried in study 1, using game test situations to measure specific tactics and creative performance for 195 expert players. The results from five evaluation criteria show that both diagnostic instruments can be used for recording football-specific creativity and game intelligence in talented young players. They produced tactical indicators that can be described as objective and valid, exhibit a sufficient degree of differentiation and are easy to record. Study 2 uses a longitudinal design to present a dynamic performance diagnostic tool for analyzing intra-individual improvements of German Soccer Foundation talents according to football-specific creativity and game intelligence. The results with respect to divergent tactical thinking clearly show that very different change processes were observed in the German Soccer Foundation players. Finally, the practical implications for the training process are discussed on the basis of both studies. Key pointsWith game test situations it is possible to assess tactical performance as game intelligence and creativity objective, valid, with a sufficient degree of differentiation, and economically.The results with respect to game intelligence and creativity show that very different change processes were observed in the German Soccer Foundation players dependend on the bases (trainers).Current literature on tactics for school sports as well as for children's, youth and high performance soccer at the club level should place much more emphasis on individual and group-tactical requirements in soccer.

Testing of Tactical Performance in Youth Elite Soccer

PubMed Central

2010-01-01

This is a twofold study with the goals of evaluating tactical oriented game test situations for 12-13-year old highly-talented soccer players and to analyze dynamic, intra-individual developments of the players. A cross-sectional design was carried in study 1, using game test situations to measure specific tactics and creative performance for 195 expert players. The results from five evaluation criteria show that both diagnostic instruments can be used for recording football-specific creativity and game intelligence in talented young players. They produced tactical indicators that can be described as objective and valid, exhibit a sufficient degree of differentiation and are easy to record. Study 2 uses a longitudinal design to present a dynamic performance diagnostic tool for analyzing intra-individual improvements of German Soccer Foundation talents according to football-specific creativity and game intelligence. The results with respect to divergent tactical thinking clearly show that very different change processes were observed in the German Soccer Foundation players. Finally, the practical implications for the training process are discussed on the basis of both studies. Key points With game test situations it is possible to assess tactical performance as game intelligence and creativity objective, valid, with a sufficient degree of differentiation, and economically. The results with respect to game intelligence and creativity show that very different change processes were observed in the German Soccer Foundation players dependend on the bases (trainers). Current literature on tactics for school sports as well as for children’s, youth and high performance soccer at the club level should place much more emphasis on individual and group-tactical requirements in soccer. PMID:24149686

Longitudinal development of match-running performance in elite male youth soccer players.

PubMed

Saward, C; Morris, J G; Nevill, M E; Nevill, A M; Sunderland, C

2016-08-01

This study longitudinally examined age-related changes in the match-running performance of retained and released elite youth soccer players aged 8-18 years. The effect of playing position on age-related changes was also considered. Across three seasons, 263 elite youth soccer players were assessed in 1-29 competitive matches (988 player-matches). For each player-match, total distance and distances covered at age group-specific speed zones (low-speed, high-speed, sprinting) were calculated using 1 Hz or 5 Hz GPS. Mixed modeling predicted that match-running performance developed nonlinearly, with age-related changes best described with quadratic age terms. Modeling predicted that playing position significantly modified age-related changes (P < 0.05) and retained players covered significantly more low-speed distance compared with released players (P < 0.05), by 75 ± 71 m/h (mean ± 95% CI; effect size ± 95% CI: 0.35 ± 0.34). Model intercepts randomly varied, indicating differences between players in match-running performance unexplained by age, playing position or status. These findings may assist experts in developing training programs specific to the match play demands of players of different ages and playing positions. Although retained players covered more low-speed distance than released players, further study of the actions comprising low-speed distance during match play is warranted to better understand factors differentiating retained and released players. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Repeated Sprint Ability with Inclusion of Changing Direction among Veteran Soccer Players

NASA Astrophysics Data System (ADS)

Salleh, Omar Md; Nadzalan, Ali Md; Ikhwan Mohamad, Nur; Rahmat, Azali; Azny Mustafa, Mirza; Tan, Kevin

2018-05-01

This study was conducted to determine the repeated sprint ability (RSA) with the inclusion of changing direction among veteran soccer players. Twelve main players from a university veteran soccer team were recruited and were required to perform the RSA test in two conditions; i) without ball and ii) with ball. Descriptive statistics and Wilcoxon signed rank test was conducted to determine the mean score and the differences of sprint time, percentage of decrement score of sprinting (Sdec) and fatigue index (FI) between the two conditions. Both conditions demonstrated significantly drop in speed in the fifth sprint. Results showed sprint time, Sdec and FI were found to be significantly different between both conditions. Findings of this study demonstrated the important for specific training to sports for performance enhancement.

Effects of plyometric training on maximal-intensity exercise and endurance in male and female soccer players.

PubMed

Ramírez-Campillo, Rodrigo; Vergara-Pedreros, Marcelo; Henríquez-Olguín, Carlos; Martínez-Salazar, Cristian; Alvarez, Cristian; Nakamura, Fábio Yuzo; De La Fuente, Carlos I; Caniuqueo, Alexis; Alonso-Martinez, Alicia M; Izquierdo, Mikel

2016-01-01

In a randomised controlled trial design, effects of 6 weeks of plyometric training on maximal-intensity exercise and endurance performance were compared in male and female soccer players. Young (age 21.1 ± 2.7 years) players with similar training load and competitive background were assigned to training (women, n = 19; men, n = 21) and control (women, n = 19; men, n = 21) groups. Players were evaluated for lower- and upper-body maximal-intensity exercise, 30 m sprint, change of direction speed and endurance performance before and after 6 weeks of training. After intervention, the control groups did not change, whereas both training groups improved jumps (effect size (ES) = 0.35-1.76), throwing (ES = 0.62-0.78), sprint (ES = 0.86-1.44), change of direction speed (ES = 0.46-0.85) and endurance performance (ES = 0.42-0.62). There were no differences in performance improvements between the plyometric training groups. Both plyometric groups improved more in all performance tests than the controls. The results suggest that adaptations to plyometric training do not differ between men and women.

Biochemical, physical and tactical analysis of a simulated game in young soccer players.

PubMed

Aquino, Rodrigo L; Gonçalves, Luiz G; Vieira, Luiz H; Oliveira, Lucas P; Alves, Guilherme F; Santiago, Paulo R; Puggina, Enrico F

2016-12-01

The objectives of this study were to describe and compare the displacement patterns and the tactical performance of the players in the first to the second game time and verify possible associations between indirect markers of muscle damage with displacement patterns in a simulated game played by young soccer players. Eighteen young soccer players were submitted to a simulated game and two blood collections, one before and another 30 minutes post-game to analyze the behavior of creatine kinase and lactate dehydrogenase enzymes. The patterns of displacement and tactics variables were obtained through functions developed in MATLAB environment (MathWorks, Inc., Natick, MA, USA). It is observed a significant increase in average speed (P=0.05), number of sprints (P<0.001), the percentage the total distance covered at high intensity (P<0.001) and tactical variables (team surface area: P=0.002; spreading: P=0.001) in the second period of the simulated game. In addition, there was significant reduction in the percentage of the total distance at low intensity (P≤0.05) in the second period, and there was a strong association between the percentage of change delta of creatine kinase and lactate dehydrogenase with the displacement patterns in the simulated game. The results show that indirect markers of muscle damage have great association with displacement patterns in game performed in training conditions for young soccer players, evidencing a need for reflection on the post-training recovery sessions strategies, contributing to better planning of sessions throughout the macrocycle.

Physical fitness, injuries, and team performance in soccer.

PubMed

Arnason, Arni; Sigurdsson, Stefan B; Gudmundsson, Arni; Holme, Ingar; Engebretsen, Lars; Bahr, Roald

2004-02-01

To investigate the relationship between physical fitness and team success in soccer, and to test for differences in physical fitness between different player positions. Participants were 306 male soccer players from 17 teams in the two highest divisions in Iceland. Just before the start of the 1999 soccer season, the following variables were tested: height and weight, body composition, flexibility, leg extension power, jump height, and peak O2 uptake. Injuries and player participation in matches and training were recorded through the 4-month competitive season. Team average physical fitness was compared with team success (final league standing) using a linear regression model. Physical fitness was also compared between players in different playing positions. A significant relationship was found between team average jump height (countermovement jump and standing jump) and team success (P = 0.009 and P = 0.012, respectively). The same trend was also found for leg extension power (P = 0.097), body composition (% body fat, P = 0.07), and the total number of injury days per team (P = 0.09). Goalkeepers demonstrated different fitness characteristics from outfield players. They were taller and heavier, more flexible in hip extension and knee flexion, and had higher leg extension power and a lower peak O2 uptake. However, only minor differences were observed between defenders, midfield players, and attackers. Coaches and medical support teams should pay more attention to jump and power training, as well as preventive measures and adequate rehabilitation of previous injuries to increase team success.

Maturation-related adaptations in running speed in response to sprint training in youth soccer players.

PubMed

Moran, Jason; Parry, Dave A; Lewis, Ieuan; Collison, Jay; Rumpf, Michael C; Sandercock, Gavin R H

2018-05-01

This study investigated the effects of a previously recommended dose of sprint training (ST) in young male soccer players of differing maturity status. Quasi-experimental design. Male soccer players from two professional academies were divided into Pre-PHV (Training: n=12; Control: n=13) and Mid-PHV (Training: n=7; Control=10) groups. The training groups completed 16 sprints of 20m with 90s recovery, once per week for 8weeks. Between-group effect sizes (ES) were substantially larger in Pre-PHV (10m [1.54, CI: 0.74-2.23]; 20m [1.49, CI: 0.75-2.23]; 5-10-5 [0.92, CI: 0.23-1.61]) than in Mid-PHV (10m [-0.00, CI: -0.81 to 0.81]; 20m [-0.12, CI: -0.93 to 0.69]; 5-10-5 [-0.41, CI: -1.22 to 0.41]). Within-group effects demonstrated a similar, though less accentuated, trend which revealed ST to be effective in both Pre-PHV (10m [0.44, CI: -0.24 to 1.12]; 20m [0.45, CI: -0.23 to 1.13]; 5-10-5 [0.69, CI: 0.00-1.38]) and Mid-PHV (10m [0.51, CI: -0.38 to 1.40]; 20m [0.33, CI: -0.56 to 1.21]; 5-10-5 [0.43, CI: -0.46 to 1.32]). ST, in the amount of 16 sprints over 20m with a 90s rest, may be more effective in Pre-PHV youths than in Mid-PHV youths. Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

The Effects of Comprehensive Warm-Up Programs on Proprioception, Static and Dynamic Balance on Male Soccer Players

PubMed Central

Daneshjoo, Abdolhamid; Mokhtar, Abdul Halim; Rahnama, Nader; Yusof, Ashril

2012-01-01

Purpose The study investigated the effects of FIFA 11+ and HarmoKnee, both being popular warm-up programs, on proprioception, and on the static and dynamic balance of professional male soccer players. Methods Under 21 year-old soccer players (n = 36) were divided randomly into 11+, HarmoKnee and control groups. The programs were performed for 2 months (24 sessions). Proprioception was measured bilaterally at 30°, 45° and 60° knee flexion using the Biodex Isokinetic Dynamometer. Static and dynamic balances were evaluated using the stork stand test and Star Excursion Balance Test (SEBT), respectively. Results The proprioception error of dominant leg significantly decreased from pre- to post-test by 2.8% and 1.7% in the 11+ group at 45° and 60° knee flexion, compared to 3% and 2.1% in the HarmoKnee group. The largest joint positioning error was in the non-dominant leg at 30° knee flexion (mean error value = 5.047), (p<0.05). The static balance with the eyes opened increased in the 11+ by 10.9% and in the HarmoKnee by 6.1% (p<0.05). The static balance with eyes closed significantly increased in the 11+ by 12.4% and in the HarmoKnee by 17.6%. The results indicated that static balance was significantly higher in eyes opened compared to eyes closed (p = 0.000). Significant improvements in SEBT in the 11+ (12.4%) and HarmoKnee (17.6%) groups were also found. Conclusion Both the 11+ and HarmoKnee programs were proven to be useful warm-up protocols in improving proprioception at 45° and 60° knee flexion as well as static and dynamic balance in professional male soccer players. Data from this research may be helpful in encouraging coaches or trainers to implement the two warm-up programs in their soccer teams. PMID:23251579

Relationships Between the External and Internal Training Load in Professional Soccer: What Can We Learn From Machine Learning?

PubMed

Jaspers, Arne; De Beéck, Tim Op; Brink, Michel S; Frencken, Wouter G P; Staes, Filip; Davis, Jesse J; Helsen, Werner F

2018-05-01

Machine learning may contribute to understanding the relationship between the external load and internal load in professional soccer. Therefore, the relationship between external load indicators (ELIs) and the rating of perceived exertion (RPE) was examined using machine learning techniques on a group and individual level. Training data were collected from 38 professional soccer players over 2 seasons. The external load was measured using global positioning system technology and accelerometry. The internal load was obtained using the RPE. Predictive models were constructed using 2 machine learning techniques, artificial neural networks and least absolute shrinkage and selection operator (LASSO) models, and 1 naive baseline method. The predictions were based on a large set of ELIs. Using each technique, 1 group model involving all players and 1 individual model for each player were constructed. These models' performance on predicting the reported RPE values for future training sessions was compared with the naive baseline's performance. Both the artificial neural network and LASSO models outperformed the baseline. In addition, the LASSO model made more accurate predictions for the RPE than did the artificial neural network model. Furthermore, decelerations were identified as important ELIs. Regardless of the applied machine learning technique, the group models resulted in equivalent or better predictions for the reported RPE values than the individual models. Machine learning techniques may have added value in predicting RPE for future sessions to optimize training design and evaluation. These techniques may also be used in conjunction with expert knowledge to select key ELIs for load monitoring.

Patellar tendinopathy in young elite soccer- clinical and sonographical analysis of a German elite soccer academy.

PubMed

Bode, Gerrit; Hammer, Thorsten; Karvouniaris, N; Feucht, M J; Konstantinidis, L; Südkamp, N P; Hirschmüller, A

2017-08-08

The prevalence of patellar tendinopathy is elevated in elite soccer compared to less explosive sports. While the burden of training hours and load is comparably high in youth elite players (age < 23 years), little is known about the prevalence of patellar tendinopathy at this age. There is only little data available on the influence of age, the amount of training, the position on the field, as well as muscular strength, range of motion, or sonographical findings in this age group. The purpose of the present study was to examine the above-mentioned parameters in all age groups of a German youth elite soccer academy. One hundred nineteen male youth soccer players (age 15,97 ± 2,24 years, height 174, 60 ± 10,16 cm, BMI 21, 24 ± 2,65) of the U-13 to U-23 teams were part of the study. Data acquisition included sport specific parameters such as footwear, amount of training hours, leg dominance, history of tendon pathologies, and clinical examination for palpatory pain, indurations, muscular circumference, and range of motion. Subjective complaints were measured with the Victorian Institute of Sport Assessment Patellar (VISA-P) Score. Furthermore, sonographical examinations (Aplio SSA-770A/80; Toshiba, Tokyo, Japan) with 12-MHz multifrequency linear transducers (8-14 MHz) of both patellar tendons were performed with special emphasis on hyper- and hypo echogenic areas, diameter and neovascularization. The prevalence of patellar tendinopathies was 13.4%. Seventy-five percent of the players complained of pain of their dominant leg with onset of pain at training in 87.5%. The injured players showed a medium amount of 10.34 ± 3.85 training hours and a medium duration of symptoms of 11.94 ± 18.75 weeks. Two thirds of players with patellar tendinopathy were at the age of 15-17 (Odds ratio 1.89) while no differences between players of the national or regional league were observed. In case of patellar tendinopathy, VISA-P was significantly lower in comparison to healthy players (mean ± SD 76.80 ± 28.56 points vs. 95.85 ± 10.37). The clinical examination revealed local pain at the distal patella, pain at stretching, and thickening of the patellar tendon (p = 0.02). The mean tendon diameter measured 2 cm distally to the patella was 4.10 ± 0.68 mm with a significantly increased diameter of 0.15 mm in case of an underlying tendinopathy (p = 0.00). The incidence of hypo-echogenic areas and neovascularizations was significantly elevated in players with patellar tendon syndrome (PTS) (p = 0.05). The prevalence of patellar tendinopathy in youth elite soccer is relatively high in comparison to available data of adult players. Especially players at the age of 15 to 17 are at considerable risk. Tendon thickening, hypo-echogenic areas, and neovascularization are more common in tendons affected by PTS.

Bilateral and Unilateral Asymmetries of Isokinetic Strength and Flexibility in Male Young Professional Soccer Players

PubMed Central

Daneshjoo, Abdolhamid; Rahnama, Nader; Mokhtar, Abdul Halim; Yusof, Ashril

2013-01-01

This study investigated bilateral and unilateral asymmetries of strength and flexibility in male young professional soccer players. Thirty-six soccer players (age: 18.9 ± 1.4 years) participated in this study. A Biodex Isokinetic Dynamometer was used to assess the hamstring and quadriceps strength at selected speeds of 60°/s, 180°/s and 300°/s. Hip joint flexibility was measured using a goniometer. No difference was observed in conventional strength ratio, dynamic control ratio and fast/slow speed ratio between the dominant and non-dominant legs (p>0.05). All but one of the players (97.2%) had musculoskeletal abnormality (bilateral imbalance > 10%) in one or more specific muscle groups. The dominant leg had greater hip joint flexibility compared with the non-dominant leg (108.8 ± 10.7° versus 104.6 ± 9.8°, respectively). The findings support the hypothesis that physical performance and movement pattern experienced during soccer playing may negatively change the balance of strength in both legs (bilateral strength balance), but not on the same leg of the young male professional soccer players. The results can be helpful for trainers and coaches to decide whether the players need to improve their balance and strength which in turn may prevent injury. It is suggested that in professional soccer training, quadriceps and hamstrings muscle strength, as well as hip joint flexibility should not be overlooked. PMID:23717354

Maturity status and injury risk in youth soccer players.

PubMed

Malina, Robert M

2010-03-01

To investigate the association of relative skeletal age and other risk factors with injury in elite schoolboy footballers (soccer players). Prospective cohort study, with players participating for varying numbers of years. Manchester United Football Club Academy, 2001 to 2007. Players were recruited to the club by scouts. At intake, the boys were medically screened to ensure they could be fully involved in the training and games program. Computerized medical records for the boys were maintained for the entire study period. The investigation included boys 9 to 16 years of age. Numbers varied between 98 and 144 per year (mean n/y = 130) over 6 years. Overall, 292 players were represented in the sample. Mean drop out per season was 21%. Each year consenting players had a radiograph of the left wrist and hand for the assessment of skeletal age (SA), using the Fels method. Eighty-five players had at least 1 radiograph and 12 players had 6 radiographs, 1 in each year of the study. Early and late maturers were those with an SA >1 year older or younger, respectively, than their chronologic age (CA). Information on demographics, height and weight, playing and training times, and position played was collected. The main outcome measure was the relation of maturity status to the occurrence of injuries. For the total sample across all the age groups the incidence of injuries was 1.44 per 1000 hours of training (n = 244 injuries), and 10.5 per 1000 match hours (n = 169 injuries). The mean number of injuries per season was 79.3, with a mean loss of 12.5 injury days per player per season. Boys aged <14 years were most vulnerable. Most injuries resulted from overuse rather than from trauma. Most common injury type and location were, respectively, soft tissue and knee joint. Mean SA for the total sample was in advance of mean CA (12.08y vs 11.74y; P < 0.05). Injury incidence did not differ significantly among late, normal, and early maturing players (1.4, 1.5, and 1.8, respectively) when training time, playing time, height, and playing position were statistically controlled as covariates (P = 0.73). However, results of general log linear analysis of mean data over the 6 seasons indicated a relationship between injury occurrence and training time, match-play time, and the CA-SA difference (P < 0.05). The 3 variables together explained 48% of the variance in injury incidence. Position played, foot dominance, and mean height gain were not related to injury occurrence. Maturity status and time spent in match play and training were significant predictors of injuries in 9- to 16-year-old elite male soccer players.

Effects of Exercise Intervention on Event-Related Potential and Task Performance Indices of Attention Networks in Children with Developmental Coordination Disorder

ERIC Educational Resources Information Center

Tsai, Chia-Liang; Wang, Chun-Hao; Tseng, Yu-Ting

2012-01-01

The study investigated whether 10-week soccer training can benefit the inhibitory control and neuroelectric indices in children with developmental coordination disorder (DCD). Fifty-one children were divided into groups of typically developing (TD, n = 21), DCD-training (n = 16), and DCD non-training (n=14) individuals using the for Children test,…

Comparative Effects of In-Season Full-Back Squat, Resisted Sprint Training, and Plyometric Training on Explosive Performance in U-19 Elite Soccer Players.

PubMed

de Hoyo, Moises; Gonzalo-Skok, Oliver; Sañudo, Borja; Carrascal, Claudio; Plaza-Armas, Jose R; Camacho-Candil, Fernando; Otero-Esquina, Carlos

2016-02-01

The aim of this study was to analyze the effects of 3 different low/moderate load strength training methods (full-back squat [SQ], resisted sprint with sled towing [RS], and plyometric and specific drills training [PLYO]) on sprinting, jumping, and change of direction (COD) abilities in soccer players. Thirty-two young elite male Spanish soccer players participated in the study. Subjects performed 2 specific strength training sessions per week, in addition to their normal training sessions for 8 weeks. The full-back squat protocol consisted of 2-3 sets × 4-8 repetitions at 40-60% 1 repetition maximum (∼ 1.28-0.98 m · s(-1)). The resisted sprint training was compounded by 6-10 sets × 20-m loaded sprints (12.6% of body mass). The plyometric and specific drills training was based on 1-3 sets × 2-3 repetitions of 8 plyometric and speed/agility exercises. Testing sessions included a countermovement jump (CMJ), a 20-m sprint (10-m split time), a 50-m (30-m split time) sprint, and COD test (i.e., Zig-Zag test). Substantial improvements (likely to almost certainly) in CMJ (effect size [ES]: 0.50-0.57) and 30-50 m (ES: 0.45-0.84) were found in every group in comparison to pretest results. Moreover, players in PLYO and SQ groups also showed substantial enhancements (likely to very likely) in 0-50 m (ES: 0.46-0.60). In addition, 10-20 m was also improved (very likely) in the SQ group (ES: 0.61). Between-group analyses showed that improvements in 10-20 m (ES: 0.57) and 30-50 m (ES: 0.40) were likely greater in the SQ group than in the RS group. Also, 10-20 m (ES: 0.49) was substantially better in the SQ group than in the PLYO group. In conclusion, the present strength training methods used in this study seem to be effective to improve jumping and sprinting abilities, but COD might need other stimulus to achieve positive effects.

jsc2018e051938

NASA Image and Video Library

2018-05-31

jsc2018e051938 - In the Integration Facility at the Baikonur Cosmodrome in Kazakhstan, the Expedition 56 prime and backup crewmembers pose for pictures May 31 with a soccer ball in front of the Soyuz booster rocket three of them will ride into space on June 6. The soccer ball and the booster bear the insignia of the FIFA World Cup soccer matches that will begin in mid-June throughout Russia. From left to right are the backup crewmembers, Anne McClain of NASA, Oleg Kononenko of Roscosmos and David Saint-Jacques of the Canadian Space Agency, and the prime crew, Serena Aunon-Chancellor of NASA, Sergey Prokopyev of Roscosmos and Alexander Gerst of the European Space Agency, who will launch June 6 in the Soyuz MS-09 spacecraft for a six-month mission on the International Space Station. ..Andrey Shelepin/Gagarin Cosmonaut Training Center.

Preventive Neuromuscular Training for Young Female Athletes: Comparison of Coach and Athlete Compliance Rates

PubMed Central

Sugimoto, Dai; Mattacola, Carl G.; Bush, Heather M.; Thomas, Staci M.; Foss, Kim D. Barber; Myer, Gregory D.; Hewett, Timothy E.

2017-01-01

Context: Fewer athletic injuries and lower anterior cruciate ligament injury incidence rates were noted in studies of neuromuscular-training (NMT) interventions that had high compliance rates. However, several groups have demonstrated that preventive NMT interventions were limited by low compliance rates. Objective: To descriptively analyze coach and athlete compliance with preventive NMT and compare the compliance between study arms as well as among school levels and sports. Design: Randomized, controlled clinical trial. Setting: Middle and high school athletic programs. Participants or Other Participants: A total of 52 teams, comprising 547 female athletes, were randomly assigned to the experimental or control group and followed for 1 athletic season. Intervention(s): The experimental group (n = 30 teams [301 athletes]: 12 basketball teams [125 athletes], 6 soccer teams [74 athletes], and 12 volleyball teams [102 athletes]) participated in an NMT program aimed at reducing traumatic knee injuries through a trunk-stabilization and hip-strengthening program. The control group (n = 22 teams [246 athletes]: 11 basketball teams [116 athletes], 5 soccer teams [68 athletes], and 6 volleyball teams [62 athletes]) performed a resistive rubber-band running program. Main Outcome Measure(s): Compliance with the assigned intervention protocols (3 times per week during the preseason [mean = 3.4 weeks] and 2 times per week in-season [mean = 11.9 weeks] of coaches [coach compliance] and athletes [athlete compliance]) was measured descriptively. Using an independent t test, we compared coach and athlete compliance between the study arms. A 2-way analysis of variance was calculated to compare differences between coach and athlete compliance by school level (middle and high schools) and sport (basketball, soccer, and volleyball). Results: The protocols were completed at a mean rate of 1.3 ± 1.1 times per week during the preseason and 1.2 ± 0.5 times per week in-season. A total of 88.4% of athletes completed 2/3 of the intervention sessions. Coach compliance was greater in the experimental group than in the control group (P = .014). Coach compliance did not differ by sport but was greater at the high school than the middle school (P = .001) level. Athlete compliance did not differ by study arm, sport, or school level. Conclusions: Athletes received instruction in about 50% of each protocol. Nearly 90% of athletes performed more than 2/3 of the assigned NMT interventions. The assigned intervention was performed more often in the experimental arm compared with the control arm. Coaches at the high school level complied with the given protocol more than middle school coaches did. Athletes complied well with the protocol, but coaches did not, especially at the middle school level. PMID:27977300

Preventive Neuromuscular Training for Young Female Athletes: Comparison of Coach and Athlete Compliance Rates.

PubMed

Sugimoto, Dai; Mattacola, Carl G; Bush, Heather M; Thomas, Staci M; Foss, Kim D Barber; Myer, Gregory D; Hewett, Timothy E

2017-01-01

 Fewer athletic injuries and lower anterior cruciate ligament injury incidence rates were noted in studies of neuromuscular-training (NMT) interventions that had high compliance rates. However, several groups have demonstrated that preventive NMT interventions were limited by low compliance rates.  To descriptively analyze coach and athlete compliance with preventive NMT and compare the compliance between study arms as well as among school levels and sports.  Randomized, controlled clinical trial.  Middle and high school athletic programs. Participants or Other Participants: A total of 52 teams, comprising 547 female athletes, were randomly assigned to the experimental or control group and followed for 1 athletic season.  The experimental group (n = 30 teams [301 athletes]: 12 basketball teams [125 athletes], 6 soccer teams [74 athletes], and 12 volleyball teams [102 athletes]) participated in an NMT program aimed at reducing traumatic knee injuries through a trunk-stabilization and hip-strengthening program. The control group (n = 22 teams [246 athletes]: 11 basketball teams [116 athletes], 5 soccer teams [68 athletes], and 6 volleyball teams [62 athletes]) performed a resistive rubber-band running program.  Compliance with the assigned intervention protocols (3 times per week during the preseason [mean = 3.4 weeks] and 2 times per week in-season [mean = 11.9 weeks] of coaches [coach compliance] and athletes [athlete compliance]) was measured descriptively. Using an independent t test, we compared coach and athlete compliance between the study arms. A 2-way analysis of variance was calculated to compare differences between coach and athlete compliance by school level (middle and high schools) and sport (basketball, soccer, and volleyball).  The protocols were completed at a mean rate of 1.3 ± 1.1 times per week during the preseason and 1.2 ± 0.5 times per week in-season. A total of 88.4% of athletes completed 2/3 of the intervention sessions. Coach compliance was greater in the experimental group than in the control group (P = .014). Coach compliance did not differ by sport but was greater at the high school than the middle school (P = .001) level. Athlete compliance did not differ by study arm, sport, or school level.  Athletes received instruction in about 50% of each protocol. Nearly 90% of athletes performed more than 2/3 of the assigned NMT interventions. The assigned intervention was performed more often in the experimental arm compared with the control arm. Coaches at the high school level complied with the given protocol more than middle school coaches did. Athletes complied well with the protocol, but coaches did not, especially at the middle school level.

Effect of insulin therapy and dietary adjustments on safety and performance during simulated soccer tests in people with type 1 diabetes: study protocol for a randomized controlled trial.

PubMed

Calvo-Marín, Javier; Torrealba-Acosta, Gabriel; Campbell, Matthew; Gaboury, Jesse; Ali, Ajmol; Chen-Ku, Chih Hao

2017-07-20

Despite the reduction in glycemic derangement in patients with type 1 diabetes mellitus (T1D) through dietary and therapeutic adjustments implemented before, during and after continuous exercise, evidence for its effectiveness with intermittent forms of exercise, such as soccer, is still lacking. We designed a study protocol for a randomized, crossover, double-blinded, controlled trial, for the evaluation of the effect that a strategy of dietary and therapeutic modifications may have on safety and performance of persons with T1D in soccer training sessions and cognitive testing. Inclusion criteria comprise: age older than 18 years, more than 2 years since T1D diagnosis, low C-peptide level, a stable insulin regimen, HbA1c less than 9.0% and regular participation in soccer activities. Our primary outcome evaluates safety regarding hypoglycemia events in patients using dietary and therapeutic adjustments, compared with the performance under the implementation of current American Diabetes Association (ADA) usual recommendations for nutritional and pharmacological adjustments for exercise. Additionally, we will evaluate as secondary outcomes: soccer performance, indexed by performance in well-established soccer skill tests, cognitive functions (indexed by Stroop, digital vigilance test (DVT), Corsi block-tapping task (CBP), and rapid visual information processing (RVIP) tests), and glycemic control measured with a continuous glucose monitor (CGM). Dietary and insulin adjustments standardized under a 4-step method strategy have never been tested in a clinical trial setting with intermittent forms of exercise, such as soccer. We hypothesize that through this strategy we will observe better performance by persons with T1D in soccer and cognitive evaluations, and more stable control of glycemic parameters before, during and after exercise execution, indexed by CGM measurements. ISRCTN, ISRCTN17447843. Registered on 5 January 2017.

Does the FIFA 11+ Injury Prevention Program Reduce the Incidence of ACL Injury in Male Soccer Players?

PubMed

Silvers-Granelli, Holly J; Bizzini, Mario; Arundale, Amelia; Mandelbaum, Bert R; Snyder-Mackler, Lynn

2017-10-01

The FIFA 11+ injury prevention program has been shown to decrease the risk of soccer injuries in men and women. The program has also been shown to decrease time loss resulting from injury. However, previous studies have not specifically investigated how the program might impact the rate of anterior cruciate ligament (ACL) injury in male soccer players. The purpose of this study was to examine if the FIFA 11+ injury prevention program can (1) reduce the overall number of ACL injuries in men who play competitive college soccer and whether any potential reduction in rate of ACL injuries differed based on (2) game versus practice setting; (3) player position; (4) level of play (Division I or II); or (5) field type. This study was a prospective cluster randomized controlled trial, which was conducted in 61 Division I and Division II National Collegiate Athletic Association men's soccer teams over the course of one competitive soccer season. The FIFA 11+ is a 15- to 20-minute on-the-field dynamic warm-up program used before training and games and was utilized as the intervention throughout the entire competitive season. Sixty-five teams were randomized: 34 to the control group (850 players) and 31 to the intervention group (675 players). Four intervention teams did not complete the study and did not submit their data, noting insufficient time to complete the program, reducing the number for per-protocol analysis to 61. Compliance to the FIFA 11+ program, athletic exposures, specific injuries, ACL injuries, and time loss resulting from injury were collected and recorded using a secure Internet-based system. At the end of the season, the data in the injury surveillance system were crosshatched with each individual institution's internal database. At that time, the certified athletic trainer signed off on the injury collection data to confirm their accuracy and completeness. A lower proportion of athletes in the intervention group experienced knee injuries (25% [34 of 136]) compared with the control group (75% [102 of 136]; relative risk [RR], 0.42; 95% confidence interval [CI], 0.29-0.61; p < 0.001). When the data were stratified for ACL injury, fewer ACL injuries were reported in the intervention group (16% [three of 19]) compared with the control group (84% [16 of 19]), accounting for a 4.25-fold reduction in the likelihood of incurring ACL injury (RR, 0.236; 95% CI, 0.193-0.93; number needed to treat = 70; p < 0.001). With the numbers available, there was no difference between the ACL injury rate within the FIFA 11+ group and the control group with respect to game and practice sessions (games-intervention: 1.055% [three of 15] versus control: 1.80% [12 of 15]; RR, 0.31; 95% CI, 0.09-1.11; p = 0.073 and practices-intervention: 0% [zero of four] versus control: 0.60% [four of four]; RR, 0.14; 95% CI, 0.01-2.59; p = 0.186). With the data that were available, there were no differences in incidence rate (IR) or injury by player position for forwards (IR control = 0.339 versus IR intervention = 0), midfielders (IR control = 0.54 versus IR intervention = 0.227), defenders (IR control = 0.339 versus IR intervention = 0.085), and goalkeepers (IR control = 0.0 versus IR intervention = 0.0) (p = 0.327). There were no differences in the number of ACL injuries for the Division I intervention group (0.70% [two of nine]) compared with the control group (1.05% [seven of nine]; RR, 0.30; CI, 0.06-1.45; p = 0.136). However, there were fewer ACL injuries incurred in the Division II intervention group (0.35% [one of 10]) compared with the control group (1.35% [nine of 10]; RR, 0.12; CI, 0.02-0.93; p = 0.042). There was no difference between the number of ACL injuries in the control group versus in the intervention group that occurred on grass versus turf (Wald chi square [1] = 0.473, b = 0.147, SE = 0.21, p = 0.492). However, there were more ACL injuries that occurred on artificial turf identified in the control group (1.35% [nine of 10]) versus the intervention group (0.35% [one of 10]; RR, 0.14; 95% CI, 0.02-1.10; p = 0.049). This program, if implemented correctly, has the potential to decrease the rate of ACL injury in competitive soccer players. In addition, this may also enhance the development and dissemination of injury prevention protocols and may mitigate risk to athletes who utilize the program consistently. Further studies are necessary to analyze the cost-effectiveness of the program implementation and to analyze the efficacy of the FIFA 11+ in the female collegiate soccer cohort. Level I, therapeutic study.

An Integrated, Multifactorial Approach to Periodization for Optimal Performance in Individual and Team Sports.

PubMed

Mujika, Iñigo; Halson, Shona; Burke, Louise M; Balagué, Gloria; Farrow, Damian

2018-05-01

Sports periodization has traditionally focused on the exercise aspect of athletic preparation, while neglecting the integration of other elements that can impact an athlete's readiness for peak competition performances. Integrated periodization allows the coordinated inclusion of multiple training components best suited for a given training phase into an athlete's program. The aim of this article is to review the available evidence underpinning integrated periodization, focusing on exercise training, recovery, nutrition, psychological skills, and skill acquisition as key factors by which athletic preparation can be periodized. The periodization of heat and altitude adaptation, body composition, and physical therapy is also considered. Despite recent criticism, various methods of exercise training periodization can contribute to performance enhancement in a variety of elite individual and team sports, such as soccer. In the latter, both physical and strategic periodization are useful tools for managing the heavy travel schedule, fatigue, and injuries that occur throughout a competitive season. Recovery interventions should be periodized (ie, withheld or emphasized) to influence acute and chronic training adaptation and performance. Nutrient intake and timing in relation to exercise and as part of the periodization of an athlete's training and competition calendar can also promote physiological adaptations and performance capacity. Psychological skills are a central component of athletic performance, and their periodization should cater to each athlete's individual needs and the needs of the team. Skill acquisition can also be integrated into an athlete's periodized training program to make a significant contribution to competition performance.

Strength Training and Your Child

MedlinePlus

... participate in organized sports or activities such as baseball, soccer, or gymnastics usually can safely to start ... these drugs to build muscles and improve athletic performance and appearance. But these drugs, some of which ...

Nonoperative Management, Rehabilitation, and Functional and Clinical Progression of Osteitis Pubis/Pubic Bone Stress in Professional Soccer Players: A Case Series.

PubMed

McAleer, Stephen S; Lippie, Ed; Norman, Darcy; Riepenhof, Helge

2017-09-01

Study Design Case series. Background Pubic bone stress (PBS) is a common acute or chronic response of the pelvis in sports where sprinting, kicking, twisting, and cutting are the dominant movements. There are few nonoperative rehabilitation strategies for the condition reported in the literature, and the outcome of conservative treatment has not been documented. Case Description Five professional and academy soccer players complaining of pubic symphysis pain, confirmed as PBS on magnetic resonance imaging and objective assessment, were treated with a nonoperative rehabilitation program that featured functional and clinical objective markers as progression criteria. Interventions in the acute phase included pharmacological and physical therapeutic modalities to reduce pain initially. Rehabilitation management focused on improving range of motion at the hips and thorax, adductor strengthening, trunk and lumbopelvic stability, gym-based strength training, and field-based rehabilitation and conditioning. Clinical follow-up was performed at least 8 months following return to play. Outcomes All players demonstrated reduced or resolved pain, increased adductor squeeze strength, and return to pain-free training and match play. Return-to-training time averaged 40.6 days (range, 30-60 days) and return to play averaged 49.4 days (range, 38-72 days) within the 5 players. At final follow-up (mean, 29.6 months; range, 16-33 months), there had been no recurrences. Discussion This report of 5 cases suggests that a nonoperative protocol, using clinical and functional progression criteria, may be successful in rehabilitating athletes with PBS for return to sport within 11 weeks. Level of Evidence Therapy, level 4. J Orthop Sports Phys Ther 2017;47(9):683-690. Epub 3 Aug 2017. doi:10.2519/jospt.2017.7314.

Dietary analysis of young professional soccer players for 1 week during the competitive season.

PubMed

Russell, Mark; Pennock, Anthony

2011-07-01

Limited data exist concerning the dietary practices of young professional soccer players that compete within the United Kingdom. Therefore, the purpose of this study was to investigate the nutritional and activity habits of professional male soccer players (n = 10; age: 17 ± 1 years, height: 1.72 ± 0.01 m, mass: 67.5 ± 1.8 kg, estimated maximal aerobic capacity: 57.8 ± 0.9 ml·kg·min) who played for the youth team of a UK-based Championship club. All players recorded their 7-day dietary intake and activity habits during a competitive week that included a match day, 4- training days, and 2 rest days in the first half of the 2009/2010 playing season. The intake of carbohydrates (5.9 ± 0.4 g·kg·d), proteins (1.7 ± 0.1 g·kg·d), and fats (1.5 ± 0.1 g·kg·d) represented 56 ± 1, 16 ± 1, and 31 ± 1% of the mean daily energy intake respectively. The intake of fiber was found to be significantly lower than Recommended Nutrient Intake (RNI) values (67% of RNI, p < 0.001), whereas all other analyzed micronutrients met or exceeded recommended values. A mean daily energy deficit of 788 ± 174 kcal existed because daily energy expenditures exceeded that of intake (3,618 ± 61 vs. 2831 ± 164 kcal, p = 0.001). The mean daily fluid intake was 3.2 ± 0.3 L. Consequently, the nutritional practices of the sampled group of professional youth soccer players were inadequate to sustain optimized performance throughout training and match play. Youth soccer players should therefore seek to ensure that their diets contain adequate energy through increased total caloric intake, while also optimizing the proportion of energy derived from carbohydrates and ensuring that enough fiber-rich foods are consumed.

Psychological Gender and Emotional Intelligence in Youth Female Soccer Players.

PubMed

Rutkowska, Katarzyna; Bergier, Józef

2015-09-29

Many sports (for instance soccer) are stereotypically perceived as a male activity. Even so, more and more women decide to become competitive athletes. Since the theory of sport requires comprehensive explanations and the practice of sport needs clear guidelines, interdisciplinary studies into the nature of sport, including its psychological aspects, are necessary. Analysing the psychological profile of female soccer players, particularly those who are about to become professional athletes, can provide many interesting insights into the specific character of female youth sport and show where improvements can be made in athletic training programmes (especially in mental training). It is therefore important to study psychological gender that determines social behaviours and to analyse female athletes' emotional intelligence. Emotional intelligence is defined as a set of emotional competencies that determine the effectiveness of human behaviours. Psychological gender and emotional intelligence have a significant effect on human adaptability and the efficiency of psychosocial functioning. This research was undertaken with the dual purpose of identifying the psychological gender and emotional intelligence of female soccer players. It involved 54 secondary-school girls, some of whom attended a sports class and others played on the Polish national team. The following tools were used to carry out the research: the Gender Assessment Inventory (IPP [This and the other acronyms derive from the Polish language]-developed by Kuczyńska) and the Emotional Intelligence Questionnaire (INTE; created by Jaworowska and Matczak). As shown by the analysis of the results, most female soccer players in the study were androgynous and the level of their emotional intelligence was significantly higher than in other participants. This also seems to point to their significantly greater adaptability. At the same time, the level of emotional intelligence in many players was average or low, which seems insufficient and calls for adequate intervention measures to be taken.

Psychological Gender and Emotional Intelligence in Youth Female Soccer Players

PubMed Central

Rutkowska, Katarzyna; Bergier, Józef

2015-01-01

Many sports (for instance soccer) are stereotypically perceived as a male activity. Even so, more and more women decide to become competitive athletes. Since the theory of sport requires comprehensive explanations and the practice of sport needs clear guidelines, interdisciplinary studies into the nature of sport, including its psychological aspects, are necessary. Analysing the psychological profile of female soccer players, particularly those who are about to become professional athletes, can provide many interesting insights into the specific character of female youth sport and show where improvements can be made in athletic training programmes (especially in mental training). It is therefore important to study psychological gender that determines social behaviours and to analyse female athletes’ emotional intelligence. Emotional intelligence is defined as a set of emotional competencies that determine the effectiveness of human behaviours. Psychological gender and emotional intelligence have a significant effect on human adaptability and the efficiency of psychosocial functioning. This research was undertaken with the dual purpose of identifying the psychological gender and emotional intelligence of female soccer players. It involved 54 secondary-school girls, some of whom attended a sports class and others played on the Polish national team. The following tools were used to carry out the research: the Gender Assessment Inventory (IPP [This and the other acronyms derive from the Polish language]-developed by Kuczyńska) and the Emotional Intelligence Questionnaire (INTE; created by Jaworowska and Matczak). As shown by the analysis of the results, most female soccer players in the study were androgynous and the level of their emotional intelligence was significantly higher than in other participants. This also seems to point to their significantly greater adaptability. At the same time, the level of emotional intelligence in many players was average or low, which seems insufficient and calls for adequate intervention measures to be taken. PMID:26673062

Seasonal Body Composition Variation Amongst Elite European Professional Soccer Players: An Approach of Talent Identification

PubMed Central

Owen, Adam Lee; Lago-Peñas, Carlos; Dunlop, Gordon; Mehdi, Rouissi; Chtara, Moktar; Dellal, Alexandre

2018-01-01

Abstract The primary aim of the investigation was to study the seasonal changes in body composition in elite European soccer players and identify key playing positional differences. Twenty-two players (age = 24 ± 3.7 years, body height = 180.45 ± 5.12 cm, body mass = 76.66 ± 5.34 kg) were tested. Players’ mass (kg), lean body mass (LBM), fat free mass (FFM), fat mass (FM), muscle girths (MG) and sum of 8 skinfolds (mm) were measured across 5 time points (T0 = Start of pre-season training; T1 = End of pre-season training; T2 = Mid-season; T3 = End of mid-season break; T4 = End of season). Players were divided into their tactical positional roles for analysis. The specific positions they were divided into included defenders (n = 8), midfielders (n = 8) and forwards (n = 6). Assessment of training and matchplay exposure were also recorded. Sites-4, Sites-7, Sites-8 and Fat Mass decreased dramatically from T0 to T1 and T2 in all playing positions (p < 0.01), while no remarkable differences were found between T2, T3 and T4. Except for defenders, calf girth and lean mass were higher in T2, T3 and T4 compared to T0 and T1 (p < 0.01). Midfielders were found to be leaner than forwards and defenders in all data collection time point sessions. Defenders showed higher values in calf girth and lean body mass than midfielders and forwards. It can be concluded from this investigation that there are large variances n positional body composition profiles amongst professional European soccer players. Furthermore, significant changes are prevalent and occur across the season from LBM, FFM, MG and skinfold assessment amongst European elite level soccer players. PMID:29922389

Injuries among Spanish male amateur soccer players: a retrospective population study.

PubMed

Herrero, Helena; Salinero, Juan José; Del Coso, Juan

2014-01-01

Soccer is the most popular sport worldwide, with about 265 million players, both professionals and amateurs. Most research investigating soccer injuries has focused on professional players because they have greater exposure time, but most soccer players are at the recreational level. To undertake a retrospective epidemiological study of the injuries sustained in Spanish amateur soccer during the 2010-2011 season. Descriptive epidemiological study. Any injuries incurred by the 134,570 recreational soccer players (aged 18-55 years) registered with the Spanish Football Federation were reported to the federation's medical staff. A standardized medical questionnaire, based on the Fédération International de Football Association (FIFA) Medical and Research Centre (F-MARC) consensus for collection procedures in studies of soccer injuries, was used to classify the injury according to type, severity, location, and treatment. A total of 15,243 injuries were reported, with an average of 0.11 injuries per player and per year. From the total number of injuries, 67.2% were classified as injuries that resulted in time loss, while the remaining 32.7% were injuries that required medical attention. Most injuries led to a minimum of 1 competitive match being missed (87%), and only 2.5% were recurrent injuries. The rate of injuries per 1000 hours of play was double during games (1.15/1000 hours) compared with during training (0.49/1000 hours). From the total number of injuries reported, 7.7% corresponded to goalkeepers, 24.2% to forwards, 33.8% to defenders, and 34.3% to midfielders. The knee (29.9%) and ankle joints (12.4%) were the most common body locations injured, while ligament sprains and ruptures accounted for 32.1% of the total injuries attended. Older amateur players (age ≥30 years) had a greater number of injuries per year and per 1000 hours of play than their younger counterparts. The risk of injury in amateur soccer is lower than that previously reported in professional players. The most common complaints in amateur players are knee ligament injuries. Further research is needed to investigate ways of reducing the incidence of injuries in amateur soccer.

Energy Expenditure and Intensity of Physical Activity in Soccer Referees During Match-Play

PubMed Central

da Silva, Alberto Inácio; Fernandes, Luiz Cláudio; Fernandez, Ricardo

2008-01-01

The aim of this study was to determine the caloric expenditure and the intensity of physical activities performed by official soccer referees during a match expressed in Metabolic Equivalent (METs). The physical activity of referees accredited by CBF (Brazilian Confederation of Soccer) was video-recorded during twenty-nine official games of Paraná Championship (Brasil), Series A and B of the 2005/2006. Computerized video analysis was used to determine the time spent in 6 locomotor activities (standing still, walking, jogging, backwards running, running and sprint). The frequency and duration of each activity were recorded and these data were utilized to calculate the distance covered by the referee. Energy expenditure values were estimated, utilizing specific equations, from the time players spent in each motor activity. The referees observed in this study had a mean age of 38.9 ± 3.8 years, body mass of 86.1 ± 7.1 kg, stature of 1.80 ± 0.07 m and a body mass index of 26.5 ± 0.6 kg·m-2. During match-play, referees covered an average distance of 9155.4 ± 70.3 meters (8411 - 9765), with a mean energy expenditure of 734.7 ± 65 kcal. This energy expenditure was significantly reduced in the second half: 359.9 ± 6.3 vs 374.7 ± 6.6 kcal (p = 0.006), and averaged to be moderate energy intensity (5 METs) with predominant utilization of the aerobic energy system. In total, during 67% of match-play the intensity was equal or lower than 3.8 METs and in 33% it was higher than 9.8 METs. The pattern of movement observed in the present study confirms that soccer refereeing may be considered as a highly intermittent exercise mode. The high to low-intensity activity ratio may be defined as 1:7.1. In conclusion, referees officiating in professional soccer matches in Brazil should perform a physical conditioning regime that provides the stamina required at this level and consume appropriate and adequate nutrition to meet the energetic demands for match-play. Key pointsIn order to elaborate a diet that sufficiently restores the athlete’s energy expenditure during training and/or competition, the first step would be to measure energy expenditure during activity.We observed that during officials matches soccer referees perform physical aerobic activities of low and moderate intensity, and present a significant decline in energy expenditure between the first and second half.The pattern of movement observed in the present report confirms that soccer referees, like players undertake intermittent type exercise.Nutritional habits of soccer referees must be adapted to their daily physical activities, short training periods and moderate energy intensity physical activity, on average, during match refereeing. PMID:24149899

Energy expenditure and intensity of physical activity in soccer referees during match-play.

PubMed

da Silva, Alberto Inácio; Fernandes, Luiz Cláudio; Fernandez, Ricardo

2008-01-01

The aim of this study was to determine the caloric expenditure and the intensity of physical activities performed by official soccer referees during a match expressed in Metabolic Equivalent (METs). The physical activity of referees accredited by CBF (Brazilian Confederation of Soccer) was video-recorded during twenty-nine official games of Paraná Championship (Brasil), Series A and B of the 2005/2006. Computerized video analysis was used to determine the time spent in 6 locomotor activities (standing still, walking, jogging, backwards running, running and sprint). The frequency and duration of each activity were recorded and these data were utilized to calculate the distance covered by the referee. Energy expenditure values were estimated, utilizing specific equations, from the time players spent in each motor activity. The referees observed in this study had a mean age of 38.9 ± 3.8 years, body mass of 86.1 ± 7.1 kg, stature of 1.80 ± 0.07 m and a body mass index of 26.5 ± 0.6 kg·m(-2). During match-play, referees covered an average distance of 9155.4 ± 70.3 meters (8411 - 9765), with a mean energy expenditure of 734.7 ± 65 kcal. This energy expenditure was significantly reduced in the second half: 359.9 ± 6.3 vs 374.7 ± 6.6 kcal (p = 0.006), and averaged to be moderate energy intensity (5 METs) with predominant utilization of the aerobic energy system. In total, during 67% of match-play the intensity was equal or lower than 3.8 METs and in 33% it was higher than 9.8 METs. The pattern of movement observed in the present study confirms that soccer refereeing may be considered as a highly intermittent exercise mode. The high to low-intensity activity ratio may be defined as 1:7.1. In conclusion, referees officiating in professional soccer matches in Brazil should perform a physical conditioning regime that provides the stamina required at this level and consume appropriate and adequate nutrition to meet the energetic demands for match-play. Key pointsIn order to elaborate a diet that sufficiently restores the athlete's energy expenditure during training and/or competition, the first step would be to measure energy expenditure during activity.We observed that during officials matches soccer referees perform physical aerobic activities of low and moderate intensity, and present a significant decline in energy expenditure between the first and second half.The pattern of movement observed in the present report confirms that soccer referees, like players undertake intermittent type exercise.Nutritional habits of soccer referees must be adapted to their daily physical activities, short training periods and moderate energy intensity physical activity, on average, during match refereeing.

Quantification and Analysis of Offensive Situations in Different Formats of Sided Games In Soccer

PubMed Central

Garcia, Jorge Diaz-Cidoncha; Román, Ignacio Refoyo; Calleja-González, Julio; Dellal, Alexandre

2014-01-01

There has been a lot of research that enabled soccer to improve: its technique, tactics and strategy through analysis and training. Nevertheless, players’ need to interact with each other turns any defending or attacking situation into complex solutions with a wide range of variables to be considered, in which the player is never isolated and must make the move that has the most positive impact on play. Fifty-four sided games played in three different formats (5v5, 7v7 and 9v9) and with two age groups (U9 and U14) were filmed at three soccer clubs in Spain in order to identify the most relevant attacking moves, from a technical and tactical perspective. This study used the observational method; it is descriptive and is applied through well-prepared systematic quantitative observation in a natural environment. A key part of the method involved viewing the match recordings and logging moves that had been categorised beforehand. Cohen’s Kappa analysis showed that the results for the most representative variables presented a substantial degree of concordance (0.61–0.80). The results show that there were significant variations depending on the game format, and the following study will present a description and analysis of the aspects that had considerable influence on attacking moves in different formats of sided games (5v5, 7v7 and 9v9). The study also presents various practical applications for the area of training and analysing both youth and professional soccer. PMID:25713680

Biomechanical and functional indicators in male semiprofessional soccer players with increased hip alpha angles vs. amateur soccer players.

PubMed

Lahner, Matthias; von Schulze Pellengahr, Christoph; Walter, Philipp Alexander; Lukas, Carsten; Falarzik, Andreas; Daniilidis, Kiriakos; von Engelhardt, Lars Victor; Abraham, Christoph; Hennig, Ewald M; Hagen, Marco

2014-03-16

Femoroacetabular impingement (FAI) is predominant in young male athletes, but not much is known about gait differences in cases of increased hip alpha angles. In our study, the hip alpha angle of Nötzli of soccer players was quantified on the basis of magnetic resonance imaging (MRI) with axial oblique sequences. The aim of the current study was to compare the rearfoot motion and plantar pressure in male semiprofessional soccer players with increased alpha angles to age-matched amateur soccer players. In a prospective analysis, male semiprofessional and amateur soccer players had an MRI of the right hip to measure the alpha angle of Nötzli. In a biomechanical laboratory setting, 14 of these participants in each group ran in two shoe conditions. Simultaneously in-shoe pressure distribution, tibial acceleration, and rearfoot motion measurements of the right foot were performed. In the semiprofessional soccer group, the mean value of the alpha angle of group was 55.1 ± 6.58° (range 43.2-76.6°) and 51.6 ± 4.43° (range 41.9-58.8°) in the amateur group. In both shoe conditions, we found a significant difference between the two groups concerning the ground reaction forces, tibial acceleration, rearfoot motion and plantar pressure parameters (P < 0.01, P < 0.05, P = 0.04). Maximum rearfoot motion is about 22% lower in the semiprofessional group compared to the amateur group in both shoe conditions. This study confirmed that semiprofessional soccer players with increased alpha angles showed differences in gait kinematics compared to the amateur group. These findings support the need for a screening program for competitive soccer players. In cases of a conspicuous gait analysis and symptomatic hip pain, FAI must be ruled out by further diagnostic tests.

Technical and physical determinants of soccer match-play performance in elite youth soccer players.

PubMed

Rowat, Owain; Fenner, Jonathan; Unnithan, Viswanath

2017-04-01

The aim of this study was to evaluate whether physical performance characteristics could be a better predictor than technical skills in determining the technical level of county soccer players in a match situation. With institutional ethics approval, 25 male youth soccer players aged 16-18.5 years from a professional soccer academy in South East Asia were selected and height and body mass were recorded. Players were tested for sexual maturity (pubertal development scale [PDS] self-assessment), aerobic capacity (yo-yo intermittent recovery test level 1 [YYIR1]), repeated sprint ability (7 x 35 m sprints) acceleration (15 m sprint) and four soccer skills tests (dribble with pass, dribbling speed, passing and shooting accuracy). Players' technical ability during match play was assessed in small-sided games of soccer (5 v 5) using a novel game technical scoring chart (scoring chart completed by coaches to assess technical performance in a match situation) developed from criteria (e.g., first touch, dribbling and two footedness) used by youth soccer coaches for talent identification. A Spearman's rank correlation showed the YYIR1 test and 15 m sprint test were limited in predicting technical match performance (r=0.03, P=0.88, r=-0.23, P=0.32 respectively). A Pearson product moment correlation showed that the repeated sprint test was also limited in predicting technical match performance (r=-0.34, P=0.14). A dribbling skill with a pass was found to be the best determinant of a player's technical ability in a match (r=-0.57, P=0.00). Talent identification and selection programs in Asian youth soccer should include a dribbling skill performed with a pass.

Is there a relationship between the playing position of soccer players and their food and macronutrient intake?

PubMed

Iglesias-Gutiérrez, Eduardo; García, Angela; García-Zapico, Pedro; Pérez-Landaluce, Javier; Patterson, Angeles M; García-Rovés, Pablo Miguel

2012-04-01

Many authors have proposed the necessity of the design and implementation of dietary and nutrition education programs for soccer players, although little information is available about the determinants of food selection and nutrient intake. The aim of this study was to evaluate the nutritional intake and eating patterns of soccer players according to their playing position in the team. Eighty-seven young male soccer players (aged 16-21 years) were recruited from the junior teams of a Spanish First Division Soccer League Club and divided into 6 positional categories (goalkeepers, full-backs, centre-backs, midfielders, wingers, and forwards). Body composition (height, weight, and body fat), performance in soccer-specific tests (jumping, sprinting, and intermittent endurance), and dietary intake (weighed food intake method) were assessed. A spontaneous higher carbohydrate intake was observed for full-backs, midfielders, and wingers (g·kg(-1) body mass: 4.9 ± 1.0, 4.9 ± 1.3, 4.9 ± 0.8; % of energy intake: 47 ± 5, 46 ± 6, 46 ± 4), compared with goalkeepers and centre-backs (g·kg(-1) of body mass: 3.9 ± 1.0, 4.3 ± 1.1; % of energy intake: 44 ± 3, 42 ± 4). These differences were related to food selection patterns, and a higher contribution to daily energy intake of cereals, derivatives, and potatoes was observed between full-backs compared with goalkeepers and centre-backs (33% vs. 27% and 25%). The magnitude of these differences is limited considering the whole diet, and an inadequate nutrient intake were observed in most individuals of every group. The design and implementation of nutrition intervention programs, taking into consideration positional differences in nutritional intake, would be useful for these players.

Nonverbal Communication of Confidence in Soccer Referees: An Experimental Test of Darwin's Leakage Hypothesis.

PubMed

Furley, Philip; Schweizer, Geoffrey

2016-12-01

The goal of the present paper was to investigate whether soccer referees' nonverbal behavior (NVB) differed based on the difficulty of their decisions and whether perceivers could detect these systematic variations. On the one hand, communicating confidence via NVB is emphasized in referee training. On the other hand, it seems feasible from a theoretical point of view that particularly following relatively difficult decisions referees have problems controlling their NVB. We conducted three experiments to investigate this question. Experiment 1 (N = 40) and Experiment 2 (N = 60) provided evidence that perceivers regard referees' NVB as less confident following ambiguous decisions as compared with following unambiguous decisions. Experiment 3 (N = 58) suggested that perceivers were more likely to debate with the referee when referees nonverbally communicated less confidence. We discuss consequences for referee training.

High-speed running and sprinting as an injury risk factor in soccer: Can well-developed physical qualities reduce the risk?

PubMed

Malone, Shane; Owen, Adam; Mendes, Bruno; Hughes, Brian; Collins, Kieran; Gabbett, Tim J

2018-03-01

This study investigated the association between high-speed running (HSR) and sprint running (SR) and injuries within elite soccer players. The impact of intermittent aerobic fitness as measured by the end speed of the 30-15 intermittent fitness test (30-15V IFT ) and high chronic workloads (average 21-day) as potential mediators of injury risk were also investigated. Observational Cohort Study. 37 elite soccer players from one elite squad were involved in a one-season study. Training and game workloads (session-RPE×duration) were recorded in conjunction with external training loads (using global positioning system technology) to measure the HSR (>14.4kmh -1 ) and SR (>19.8kmh -1 ) distance covered across weekly periods during the season. Lower limb injuries were also recorded. Training load and GPS data were modelled against injury data using logistic regression. Odds ratios (OR) were calculated with 90% confidence intervals based on 21-day chronic training load status (sRPE), aerobic fitness, HSR and SR distance with these reported against a reference group. Players who completed moderate HSR (701-750-m: OR: 0.12, 90%CI: 0.08-0.94) and SR distances (201-350-m: OR: 0.54, 90%CI: 0.41-0.85) were at reduced injury risk compared to low HSR (≤674-m) and SR (≤165-m) reference groups. Injury risk was higher for players who experienced large weekly changes in HSR (351-455-m; OR: 3.02; 90%CI: 2.03-5.18) and SR distances (between 75-105-m; OR: 6.12, 90%CI: 4.66-8.29). Players who exerted higher chronic training loads (≥2584 AU) were at significantly reduced risk of injury when they covered 1-weekly HSR distances of 701-750m compared to the reference group of <674m (OR=0.65, 90% CI 0.27-0.89). When intermittent aerobic fitness was considered based on 30-15V IFT performance, players with poor aerobic fitness had a greater risk of injury than players with better-developed aerobic fitness. Exposing players to large and rapid increases in HSR and SR distances increased the odds of injury. However, higher chronic training loads (≥2584 AU) and better intermittent aerobic fitness off-set lower limb injury risk associated with these running distances in elite soccer players. Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Grassroot Soccer Resiliency Pilot Program: Building Resiliency through Sport-Based Education in Zambia and South Africa

ERIC Educational Resources Information Center

Peacock-Villada, Paola; DeCelles, Jeff; Banda, Peter S.

2007-01-01

Grassroot Soccer (GRS), a U.S.-based nonprofit organization, designed a curriculum and sport-based teaching model to build resiliency, targeting boys and girls in Lusaka, Zambia, and Johannesburg, South Africa, where most children are reminded daily of the devastation caused by AIDS and where many face chronic and acute hardship. Collaborating…

Longitudinal Study of Repeated Sprint Performance in Youth Soccer Players of Contrasting Skeletal Maturity Status

PubMed Central

Valente-dos-Santos, João; Coelho-e-Silva, Manuel J.; Severino, Vítor; Duarte, João; Martins, Raúl S.; Figueiredo, António J.; Seabra, André T.; Philippaerts, Renaat M.; Cumming, Sean P; Elferink-Gemser, Marije; Malina, Robert M.

2012-01-01

The purpose of the study was to evaluate the developmental changes in performance in a repeated-sprint ability (RSA) test in young soccer players of contrasting maturity status. A total of 83 regional level Portuguese youth soccer players, aged 11-13 years at baseline was assessed annually. Stature, body mass, 7x34.2-m sprint protocol (25-s active recovery), 20-m multi-stage continuous shuttle endurance run and counter-movement jump (CMJ) without the use of the arms were measured. Fat-free mass (FFM) was determined by age and gender-specific formulas. Developmental changes in total sprint time across ages were predicted using multilevel modeling. Corresponding measurements were performed on an independent cross-sectional subsample of 52 youth soccer players 11-17 years to evaluate the predictive model. CA, CA2, maturational status (SA-CA), body size (mass and stature), FFM, aerobic endurance, lower limb explosive strength and annual volume training significantly improved the statistical fit of the RSA multilevel model. In ‘late’ maturing athletes, the best model for predicting change in RSA was expressed by the following equation: 86.54 - 2.87 x CA + 0.05 x CA2 - 0.25 x FFM + 0.15 x body mass + 0.05 x stature - 0.05 x aerobic endurance - 0.09 x lower limb explosive strength - 0.01 x annual volume training. The best fitting models for players who were ‘on time’ and ‘early’ maturing were identical to the best model for late maturing players, less 0.64 seconds and 1.74 seconds, respectively. Multilevel modeling provided performance curves that permitted the prediction of individual RSA performance across adolescent years in regional level soccer players. Key pointsRepeated-sprint ability tests are a valuable sport-specific field test of sprint performance in youth soccer players. Here, the test had reasonable reliability and can be useful to trainers and coaches in the assessment of young athletes and in monitoring changes over time.The total sprint time of youth soccer players advanced in biological maturation improves more, on average, than that of players who are on time (average) and late in maturation. The performance difference between early and late maturing players is consistent after about 13 years of age.Multilevel modeling is a promising statistical technique for analyzing the development of functional capacity in a sport. It has the potential to provide useful information to assist trainers and coaches in evaluating and facilitating the development of individual players. PMID:24149342

Psychological Skills Development and Maintenance in Professional Soccer Players: An Experimental Design with Follow Up Measures

ERIC Educational Resources Information Center

Miçoogullari, Bülent Okan

2016-01-01

Psychological skills training and Psychological well-being (PWB) are two essential concepts not only for general mental health but also for athletic performance in sport settings. However, the effects of problems in Sport Training Scale (PSTS) on sport performance and general psychological well-being have not been systematically examined through…

Lower-extremity strength ratios of professional soccer players according to field position.

PubMed

Ruas, Cassio V; Minozzo, Felipe; Pinto, Matheus D; Brown, Lee E; Pinto, Ronei S

2015-05-01

Previous investigators have proposed that knee strength, hamstrings to quadriceps, and side-to-side asymmetries may vary according to soccer field positions. However, different results have been found in these variables, and a generalization of this topic could lead to data misinterpretation by coaches and soccer clubs. Thus, the aim of this study was to measure knee strength and asymmetry in soccer players across different field positions. One hundred and two male professional soccer players performed maximal concentric and eccentric isokinetic knee actions on the preferred and nonpreferred legs at a velocity of 60° · s. Players were divided into their field positions for analysis: goalkeepers, side backs, central backs, central defender midfielders, central attacking midfielders, and forwards. Results demonstrated that only goalkeepers (GK) differed from most other field positions on players' characteristics, and concentric peak torque across muscles. Although all players presented functional ratios of the preferred (0.79 ± 0.14) and nonpreferred (0.75 ± 0.13) legs below accepted normative values, there were no differences between positions for conventional or functional strength ratios or side-to-side asymmetry. The same comparisons were made only between field players, without inclusion of the GK, and no differences were found between positions. Therefore, the hamstrings to quadriceps and side-to-side asymmetries found here may reflect knee strength functional balance required for soccer skills performance and game demands across field positions. These results also suggest that isokinetic strength profiles should be considered differently in GK compared with other field positions due to their specific physiological and training characteristics.

Planning Training Workload in Football Using Small-Sided Games' Density.

PubMed

Sangnier, Sebastien; Cotte, Thierry; Brachet, Olivier; Coquart, Jeremy; Tourny, Claire

2018-05-08

Sangnier, S, Cotte, T, Brachet, O, Coquart, J, and Tourny, C. Planning training workload in football using small-sided games density. J Strength Cond Res XX(X): 000-000, 2018-To develop the physical qualities, the small-sided games' (SSGs) density may be essential in soccer. Small-sided games are games in which the pitch size, players' number, and rules are different to those for traditional soccer matches. The purpose was to assess the relation between training workload and SSGs' density. The 33 densities data (41 practice games and 3 full games) were analyzed through global positioning system (GPS) data collected from 25 professional soccer players (80.7 ± 7.0 kg; 1.83 ± 0.05 m; 26.4 ± 4.9 years). From total distance, distance metabolic power, sprint distance, and acceleration distance, the data GPS were divided into 4 categories: endurance, power, speed, and strength. Statistical analysis compared the relation between GPS values and SSGs' densities, and 3 methods were applied to assess models (R-squared, root-mean-square error, and Akaike information criterion). The results suggest that all the GPS data match the player's essential athletic skills. They were all correlated with the game's density. Acceleration distance, deceleration distance, metabolic power, and total distance followed a logarithmic regression model, whereas distance and number of sprints follow a linear regression model. The research reveals options to monitor the training workload. Coaches could anticipate the load resulting from the SSGs and adjust the field size to the players' number. Taking into account the field size during SSGs enables coaches to target the most favorable density for developing expected physical qualities. Calibrating intensity during SSGs would allow coaches to assess each athletic skill in the same conditions of intensity as in the competition.

Case Study: Nutritional and Lifestyle Support to Reduce Infection Incidence in an International-Standard Premier League Soccer Player.

PubMed

Ranchordas, Mayur K; Bannock, Laurent; Robinson, Scott L

2016-04-01

Professional soccer players are exposed to large amounts of physiological and psychological stress, which can increase infection risk and threaten availability for training and competition. Accordingly, it is important for practitioners to implement strategies that support player well-being and prevent illness. This case study demonstrates how a scientifically supported and practically applicable nutrition and lifestyle strategy can reduce infection incidence in an illness-prone professional soccer player. In the 3 months before the intervention, the player had 3 upper-respiratory tract infections (URTIs) and subsequently missed 3 competitive matches and 2 weeks' training. He routinely commenced morning training sessions in the fasted state and was estimated to be in a large daily energy deficit. Throughout the 12-week intervention, the amount, composition, and timing of energy intake was altered, quercetin and vitamin D were supplemented, and the player was provided with a daily sleep and hygiene protocol. There was a positive increase in serum vitamin D 25(OH) concentration from baseline to Week 12 (53 n·mol-1 to 120 n·mol-1) and salivary immunoglobulin-A (98 mg·dl-1 to 135 mg·dl-1), as well as a decline in the number of URTI symptoms (1.8 ± 2.0 vs. 0.25 ± 0.5 for Weeks 0-4 and Weeks 8-12, respectively). More important, he maintained availability for all training and matches over the 12-week period. We offer this case study as a real-world applied example for other players and practitioners seeking to deploy nutrition and lifestyle strategies to reduce risk of illness and maximize player availability.

Injuries of the obturator muscles in professional soccer players.

PubMed

Wong-On, Manuel; Turmo-Garuz, Antonio; Arriaza, Rafael; Gonzalez de Suso, Jose Manuel; Til-Perez, Luis; Yanguas-Leite, Xavier; Diaz-Cueli, David; Gasol-Santa, Xavier

2017-02-10

Obturator externus and internus muscular tears are uncommon injuries. Only a few case reports exist, mainly in high-level athletes. Our aim is to describe a series of obturator externus and internus muscular tears in professional soccer players. Injury data from four teams from the First Division of the Spanish Soccer League were collected over a total of four seasons. Any soccer player who sustained an injury to either the obturator externus or internus identified on magnetic resonance (MRI) was included. All injured players were treated non-operatively with a goal of returning to play as fast as possible. Sixteen players sustained injuries to the obturator externus and internus during matches or training sessions. The main complaint was anterior hip pain with a physical examination showing pain during internal rotation or external rotation of the flexed hip. The MRI documented 12 muscular tears of the obturator externus, and 4 muscular tears of the obturator internus. All injuries were treated conservatively based on physical therapy, analgesic medications, and underwent a symptoms-based rehabilitation protocol. Mean return to play was 11.5  ±  8.8 days. Although uncommon, tears of the obturator externus and internus occur in professional soccer players. The MRI scan was essential to the location, classification, and evaluation of the injury size. The clinical relevance of our investigation is based on the relatively benign prognosis of these injuries. IV.

Sport-specific biomechanical responses to an ACL injury prevention programme: A randomised controlled trial.

PubMed

Taylor, Jeffrey B; Ford, Kevin R; Schmitz, Randy J; Ross, Scott E; Ackerman, Terry A; Shultz, Sandra J

2018-04-19

Anterior cruciate ligament (ACL) injury prevention programmes have not been as successful at reducing injury rates in women's basketball as in soccer. This randomised controlled trial (ClinicalTrials.gov #NCT02530333) compared biomechanical adaptations in basketball and soccer players during jump-landing activities after an ACL injury prevention programme. Eighty-seven athletes were cluster randomised into intervention (6-week programme) and control groups. Three-dimensional biomechanical analyses of drop vertical jump (DVJ), double- (SAG-DL) and single-leg (SAG-SL) sagittal, and double- (FRONT-DL) and single-leg (FRONT-SL) frontal plane jump landing tasks were tested before and after the intervention. Peak angles, excursions, and joint moments were analysed using two-way MANCOVAs of post-test scores while controlling for pre-test scores. During SAG-SL the basketball intervention group exhibited increased peak knee abduction angles (p = .004) and excursions (p = .003) compared to the basketball control group (p = .01) and soccer intervention group (p = .01). During FRONT-SL, the basketball intervention group exhibited greater knee flexion excursion after training than the control group (p = .01), but not the soccer intervention group (p = .11). Although women's soccer players exhibit greater improvements in knee abduction kinematics than basketball players, these athletes largely exhibit similar biomechanical adaptations to ACL injury prevention programmes.

A feedback inclusive neuromuscular training program alters frontal plane kinematics.

PubMed

Greska, Eric K; Cortes, Nelson; Van Lunen, Bonnie L; Oñate, James A

2012-06-01

Anterior cruciate ligament (ACL) neuromuscular training programs have demonstrated beneficial effects in reducing ACL injuries, yet further evaluation of their effects on biomechanical measures across a sports team season is required to elucidate the specific factors that are modifiable. The purpose of this study was to evaluate the effects of a 10-week off-season neuromuscular training program on lower extremity kinematics. Twelve Division I female soccer players (age: 19.2 ± 0.8 years, height: 1.67 ± 0.1 m, weight: 60.2 ± 6.5 kg) performed unanticipated dynamic trials of a running stop-jump task pretraining and posttraining. Data collection was performed using an 8-camera Vicon system (Los Angeles, CA, USA) and 2 Bertec (Columbus, OH, USA) force plates. The 10-week training program consisted of resistance training 2 times per week and field training, consisting of plyometric, agility, and speed drills, 2 times per week. Repeated measures analyses of variance (ANOVAs) were used to assess the differences between pretraining and posttraining kinetics and kinematics of the hip, knee, and ankle at initial contact (IC), peak knee flexion (PKF), and peak stance. Repeated measures ANOVAs were also used to assess isometric strength differences pretraining and posttraining. The alpha level was set at 0.05 a priori. The training program demonstrated significant increases in left hip extension, left and right hip flexion, and right hip adduction isometric strength. At IC, knee abduction angle moved from an abducted to an adducted position (-1.48 ± 3.65° to 1.46 ± 3.86°, p = 0.007), and hip abduction angle increased (-6.05 ± 4.63° to -10.34 ± 6.83°, p = 0.007). Hip abduction angle at PKF increased (-2.23 ± 3.40° to 6.01 ± 3.82°, p = 0.002). The maximum knee extension moment achieved at peak stance increased from pretraining to posttraining (2.02 ± 0.32 to 2.38 ± 0.75 N·m·kg⁻¹, p = 0.027). The neuromuscular training program demonstrated a potential positive effect in altering mechanics that influence the risk of incurring an ACL injury.

Efficacy of the FIFA 11+ Injury Prevention Program in the Collegiate Male Soccer Player

PubMed Central

Silvers-Granelli, Holly; Mandelbaum, Bert; Adeniji, Ola; Insler, Stephanie; Bizzini, Mario; Pohlig, Ryan; Junge, Astrid; Snyder-Mackler, Lynn; Dvorak, Jiri

2016-01-01

Background The Fédération Internationale de Football Association (FIFA) 11+ program has been shown to be an effective injury prevention program in the female soccer cohort, but there is a paucity of research to demonstrate its efficacy in the male population. Hypothesis To examine the efficacy of the FIFA 11+ program in men's collegiate United States National Collegiate Athletic Association (NCAA) Division I and Division II soccer. Study Design Randomized controlled trial; Level of evidence, 1. Methods Before the commencement of the fall 2012 season, every NCAA Division I and Division II men's collegiate soccer team (N = 396) was solicited to participate in this research study. Human ethics review board approval was obtained through Quorum Review IRB. Sixty-five teams were randomized: 34 to the control group (CG; 850 players) and 31 to the intervention group (IG; 675 players). Four teams in the IG did not complete the study, reducing the number for analysis to 61. The FIFA 11+ injury prevention program served as the intervention and was utilized weekly. Athlete-exposures (AEs), compliance, and injury data were recorded using a secure Internet-based system. Results In the CG, 665 injuries (mean ± SD, 19.56 ± 11.01) were reported for 34 teams, which corresponded to an incidence rate (IR) of 15.04 injuries per 1000 AEs. In the IG, 285 injuries (mean ± SD, 10.56 ± 3.64) were reported for 27 teams, which corresponded to an IR of 8.09 injuries per 1000 AEs. Total days missed because of injury were significantly higher for the CG (mean ± SD, 13.20 ± 26.6 days) than for the IG (mean ± SD, 10.08 ± 14.68 days) (P = .007). There was no difference for time loss due to injury based on field type (P = .341). Conclusion The FIFA 11+ significantly reduced injury rates by 46.1% and decreased time loss to injury by 28.6% in the competitive male collegiate soccer player (rate ratio, 0.54 [95% CI, 0.49-0.59]; P < .0001) (number needed to treat = 2.64). PMID:26378030

The effects of formalized and trained non-reciprocal peer teaching on psychosocial, behavioral, pedagogical, and motor learning outcomes in physical education.

PubMed

Whipp, Peter R; Jackson, Ben; Dimmock, James A; Soh, Jenny

2015-01-01

Peer teaching is recognized as a powerful instructional method; however, there is a paucity of studies that have evaluated the outcomes experienced by peer-teachers and their student recipients in the context of trained, non-reciprocal, high school physical education (PE). Accordingly, the effectiveness of a formalized and trained non-reciprocal peer teaching (T-PT) program upon psychosocial, behavioral, pedagogical, and student learning outcomes within high school PE classes was investigated. Students from eight intact classes (106 males, 94 females, Mage = 12.46, SD = 0.59) were randomly assigned to either a T-PT intervention group (taught by a volunteer peer-teacher who was trained in line with a tactical games approach) or untrained group (U-PT; where volunteer peer-teachers received no formal training, but did receive guidance on the game concepts to teach). Data were collected over 10 lessons in a 5-week soccer unit. Mixed-model ANOVAs/MANOVAs revealed that, in comparison to U-PT, the T-PT program significantly enhanced in-game performance actions and academic learning time among student recipients. Those in the T-PT also provided greater levels of feedback and structured learning time, as well as reporting more positive feelings about peer teaching and fewer perceived barriers to accessing learning outcomes. These findings show that non-reciprocal peer-teachers who receive formalized support through training and tactical games approach-based teaching resources can enhance behavioral, pedagogical, and motor performance outcomes in PE.

The effects of formalized and trained non-reciprocal peer teaching on psychosocial, behavioral, pedagogical, and motor learning outcomes in physical education

PubMed Central

Whipp, Peter R.; Jackson, Ben; Dimmock, James A.; Soh, Jenny

2015-01-01

Peer teaching is recognized as a powerful instructional method; however, there is a paucity of studies that have evaluated the outcomes experienced by peer-teachers and their student recipients in the context of trained, non-reciprocal, high school physical education (PE). Accordingly, the effectiveness of a formalized and trained non-reciprocal peer teaching (T-PT) program upon psychosocial, behavioral, pedagogical, and student learning outcomes within high school PE classes was investigated. Students from eight intact classes (106 males, 94 females, Mage = 12.46, SD = 0.59) were randomly assigned to either a T-PT intervention group (taught by a volunteer peer-teacher who was trained in line with a tactical games approach) or untrained group (U-PT; where volunteer peer-teachers received no formal training, but did receive guidance on the game concepts to teach). Data were collected over 10 lessons in a 5-week soccer unit. Mixed-model ANOVAs/MANOVAs revealed that, in comparison to U-PT, the T-PT program significantly enhanced in-game performance actions and academic learning time among student recipients. Those in the T-PT also provided greater levels of feedback and structured learning time, as well as reporting more positive feelings about peer teaching and fewer perceived barriers to accessing learning outcomes. These findings show that non-reciprocal peer-teachers who receive formalized support through training and tactical games approach-based teaching resources can enhance behavioral, pedagogical, and motor performance outcomes in PE. PMID:25741309

Circadian variation and soccer performance: implications for training and match-play during Ramadan.

PubMed

Drust, B; Ahmed, Q; Roky, R

2012-01-01

Ramadan results in a number of behavioural alterations in individuals when compared to their normal habits outside of this holy month. These changes in behaviour could impact upon the effectiveness of the activity of an elite athlete who has high daily activity levels and energy expenditures. Understanding the true impact of Ramadan on human physiology will also require an awareness of the key aspects of circadian rhythms. This article will present theoretical background content on circadian rhythms along with data on the potential influence of circadian variation on soccer performance. It will also attempt to provide an insight into the problems of partial sleep deprivation and travel for the elite player. The contents will suggest that there is a basis for the within-day variation in physiological and psychological function to impact soccer performance if games are played early in the day or very late at night. As competitive fixtures are uncommon at these times these influences may be more relevant to the timing and organisation of training sessions. It is also likely that a lack of sleep and excessive travel will provide conditions that are not conducive to optimal performance. This would indicate that teams should think carefully about their preparation strategies for important tournaments and games.

Unsupervised symmetrical trademark image retrieval in soccer telecast using wavelet energy and quadtree decomposition

NASA Astrophysics Data System (ADS)

Ong, Swee Khai; Lim, Wee Keong; Soo, Wooi King

2013-04-01

Trademark, a distinctive symbol, is used to distinguish products or services provided by a particular person, group or organization from other similar entries. As trademark represents the reputation and credit standing of the owner, it is important to differentiate one trademark from another. Many methods have been proposed to identify, classify and retrieve trademarks. However, most methods required features database and sample sets for training prior to recognition and retrieval process. In this paper, a new feature on wavelet coefficients, the localized wavelet energy, is introduced to extract features of trademarks. With this, unsupervised content-based symmetrical trademark image retrieval is proposed without the database and prior training set. The feature analysis is done by an integration of the proposed localized wavelet energy and quadtree decomposed regional symmetrical vector. The proposed framework eradicates the dependence on query database and human participation during the retrieval process. In this paper, trademarks for soccer games sponsors are the intended trademark category. Video frames from soccer telecast are extracted and processed for this study. Reasonably good localization and retrieval results on certain categories of trademarks are achieved. A distinctive symbol is used to distinguish products or services provided by a particular person, group or organization from other similar entries.

An analysis of practice activities and instructional behaviours used by youth soccer coaches during practice: exploring the link between science and application.

PubMed

Ford, Paul R; Yates, Ian; Williams, A Mark

2010-03-01

We examined the practice activities and instructional behaviours employed by 25 youth soccer coaches during 70 different practice sessions. We evaluated the extent to which these activities and behaviours differ from those shown in contemporary research to best facilitate skill acquisition. Nine coaches worked with the under-9 years age group and eight coaches each with the under-13 and under-16 years age groups; nine of those coaches were employed at the elite level, nine at the sub-elite level, and seven at the non-elite level. Coaches had players spend more time in activities that were deemed less relevant to soccer match performance, termed "training form" (e.g. physical training, technique and skills practices), than activities deemed more relevant, termed "playing form" (e.g. small-sided/conditioned games and phase of play activities). Coaches provided high levels of instruction, feedback, and management, irrespective of the activity in which players engaged. Few differences in practice activities and instructional behaviours were reported across skill and age groups, implying the absence of any notable age- or skill-related progression. Findings are discussed with reference to recent research in the areas of skill acquisition, motor learning, and expert performance.

Influence of Endurance Training During Childhood on Total Hemoglobin Mass.

PubMed

Prommer, Nicole; Wachsmuth, Nadine; Thieme, Ina; Wachsmuth, Christian; Mancera-Soto, Erica M; Hohmann, Andreas; Schmidt, Walter F J

2018-01-01

Elite endurance athletes are characterized by markedly increased hemoglobin mass (Hbmass). It has been hypothesized that this adaptation may occur as a response to training at a very young age. Therefore, the aim of this study was to monitor changes in Hbmass in children aged 8-14 years following systematic endurance training. In the first study, Hbmass, VO2max, and lean body mass (LBM) were measured in 17 endurance-trained children (13 boys and 4 girls; aged 9.7 ± 1.3 years; training history 1.5±1.8 years; training volume 3.5 ± 1.6 h) twice a year for up to 3.5 years. The same parameters were measured once in a control group of 18 age-matched untrained children. Hbmass and blood volume (BV) were measured using the optimized CO-rebreathing technique, VO2max by an incremental test on a treadmill, and LBM by skin-fold measurements. In the second pilot study, the same parameters were measured in 9 young soccer athletes (aged 7.8 ± 0.2 years), and results were assessed in relation to soccer performance 2.5 years later. The increase in mean Hbmass during the period of study was 50% which was closely related to changes in LBM ( r = 0.959). A significant impact of endurance training on Hbmass was observed in athletes exercising more than 4 h/week [+25.4 g compared to the group with low training volume (<2 h/week)]. The greatest effects were related to LBM (11.4 g·kg -1 LBM) and overlapped with the effects of age. A strong relationship was present between absolute Hbmass and VO2max ( r = 0.939), showing that an increase of 1 g hemoglobin increases VO2max by 3.6 ml·min -1 . Study 2 showed a positive correlation between Hbmass and soccer performance 2.5 years later at age 10.3 ± 0.3 years ( r = 0.627, p = 0.035). In conclusion, children with a weekly training volume of more than 4 h show a 7% higher Hbmass than untrained children. Although this training effect is significant and independent of changes in LBM, the major factor driving the increase in Hbmass is still LBM.

The effects of short term detraining and retraining on physical fitness in elite soccer players

PubMed Central

2018-01-01

Purpose The aim of this study was to examine the effects of aerobic high-intensity training with reduced volume and training cessation on body composition and physical fitness after the end of season and the time required to recapture physical fitness with intensified retraining following two weeks of detraining in elite soccer players. Method Twenty male semi-professional soccer players participated in this study. The soccer players were assigned to either a group that completed high-intensity aerobic training (HAT, n = 10) or to a detraining and retraining group (DHAT, n = 10) for a 5-week period immediately after the end of the season. The first 2 weeks of the period, members of the HAT group performed high-intensity aerobic exercise (80–90% of HRmax, 12 min × 3, three times per week), whereas members of the DHAT group abstained from any physical activity. During the subsequent 3 weeks, members of both the HAT and DHAT groups completed high-intensity aerobic exercise. Exercise performance testing and body composition analysis were performed before; after 2 weeks of detraining; and at 1, 2 and 3 weeks of retraining. Results Intensified high-intensity training for 5 weeks maintained the performance in the Yo-Yo Intermittent Recovery level 2 test (Yo-Yo IR2) and repeated sprints at any time point (P > 0.05). However 2 weeks of detraining resulted in significant decreases in the performance on the Yo-Yo IR2 (P < 0.01) and repeated sprints test (P < 0.05). Performance on the Yo-Yo IR2 enhanced after 2 weeks of retraining and was maintained up to 3 weeks after retraining, with no significant differences between conditions (P > 0.05). In addition, repeated sprint performance markedly decreased after the detraining period (P < 0.05) and was continuously lower compared to the baseline at 2 weeks after retraining (P < 0.05). Furthermore, this value reached baseline level at the end of the experimental period (P > 0.05). There were no significant differences between conditions in body composition, performance of agility, or sprint ability throughout the 5-week experimental period (P > 0.05). Conclusions The present data suggest that short-term detraining after the competitive season can markedly decrease performances in the Yo-Yo IR2 test and repeated sprints. To return to a previous level of ability on the Yo-Yo IR2 and/or sprint test with retraining through high-intensity aerobic training after a period of detraining, a similar or longer period of retraining is required. However, the high-intensity training with reduced amount of training after competitive season can prevent reductions in physical fitness. PMID:29746505

Fluid and Electrolyte Needs for Training, Competition, and Recovery

DTIC Science & Technology

2011-01-01

begin both training and competition in a state of fluid deficit. Analysis of samples collected from elite football ( soccer ) players before training...surprisingly, samples collected from players before a competitive game revealed that 8 of the 20 outfield players had a urine osmolality in excess of...2007) reported that basketball players attempted fewer shots and were less able to make shots linked with movement (e.g. lay-up) when dehydration had

The Effects of the Gaelic Athletic Association 15 Training Program on Neuromuscular Outcomes in Gaelic Football and Hurling Players: A Randomized Cluster Trial.

PubMed

OʼMalley, Edwenia; Murphy, John C; McCarthy Persson, Ulrik; Gissane, Conor; Blake, Catherine

2017-08-01

O'Malley, E, Murphy, JC, McCarthy Persson, U, Gissane, C, and Blake, C. The effects of the Gaelic Athletic Association 15 training program on neuromuscular outcomes in Gaelic football and hurling players: A randomized cluster trial. J Strength Cond Res 31(8): 2119-2130, 2017-Team-based neuromuscular training programs for injury prevention have been tested primarily in female and adolescent athletes in soccer, handball, and basketball with limited research in adult male field sports. This study explored whether the GAA 15, a multifaceted 8-week neuromuscular training program developed by the Gaelic Athletic Association (GAA), could improve risk factors for lower limb injury in male Gaelic footballers and hurlers. Four Gaelic sports collegiate teams were randomized into intervention or control groups. Two teams (n = 41), one football and one hurling, were allocated to the intervention, undertaking a 15 minutes program of neuromuscular training exercises at the start of team training sessions, twice weekly for 8 weeks. Two matched teams (n = 37) acted as controls, participating in usual team training. Lower extremity stability (Y-Balance test [YBT]) and jump-landing technique using the Landing Error Scoring System (LESS) were assessed preintervention and postintervention. There were moderate effect sizes in favor of the intervention for right (d = 0.59) and left (d = 0.69) composite YBT scores, with adjusted mean differences between intervention and control of 3.85 ± 0.91% and 4.34 ± 0.92% for right and left legs, respectively (p < 0.001). There was a greater reduction in the mean LESS score in favor of the intervention group after exercise training (Cohen's d = 0.72, adjusted mean difference 2.49 ± 0.54, p < 0.001). Clinically and statistically significant improvements in dynamic balance and jump-landing technique occurred in collegiate level Gaelic football and hurling players who adopted the GAA 15, when compared with usual training. These findings support application and evaluation of the GAA 15 in other player groups within the Gaelic games playing population.

Specific Changes in Young Soccer Player's Fitness After Traditional Bilateral vs. Unilateral Combined Strength and Plyometric Training

PubMed Central

Ramirez-Campillo, Rodrigo; Sanchez-Sanchez, Javier; Gonzalo-Skok, Oliver; Rodríguez-Fernandez, Alejandro; Carretero, Manuel; Nakamura, Fabio Y.

2018-01-01

The aim of this study was to compare changes in young soccer player's fitness after traditional bilateral vs. unilateral combined plyometric and strength training. Male athletes were randomly divided in two groups; both received the same training, including strength training for knee extensors and flexors, in addition to horizontal plyometric training drills. The only difference between groups was the mode of drills technique: unilateral (UG; n = 9; age, 17.3 ± 1.1 years) vs. bilateral (TG; n = 9; age, 17.6 ± 0.5 years). One repetition maximum bilateral strength of knee muscle extensors (1RM_KE) and flexors (1RM_KF), change of direction ability (COD), horizontal and vertical jump ability with one (unilateral) and two (bilateral) legs, and limb symmetry index were measured before and after an 8-week in-season intervention period. Some regular soccer drills were replaced by combination of plyometric and strength training drills. Magnitude-based inference statistics were used for between-group and within-group comparisons. Beneficial effects (p < 0.05) in 1RM_KE, COD, and several test of jumping performance were found in both groups in comparison to pre-test values. The limb symmetry index was not affected in either group. The beneficial changes in 1RM_KE (8.1%; p = 0.074) and 1RM_KF (6.7%; p = 0.004), COD (3.1%; p = 0.149), and bilateral jump performance (from 2.7% [p = 0.535] to 10.5% [p = 0.002]) were possible to most likely beneficial in the TG than in the UG. However, unilateral jump performance measures achieved likely to most likely beneficial changes in the UG compared to the TG (from 4.5% [p = 0.090] to 8.6% [p = 0.018]). The improvements in jumping ability were specific to the type of jump performed, with greater improvements in unilateral jump performance in the UG and bilateral jump performance in the TG. Therefore, bilateral strength and plyometric training should be complemented with unilateral drills, in order to maximize adaptations. PMID:29623049

Specific Changes in Young Soccer Player's Fitness After Traditional Bilateral vs. Unilateral Combined Strength and Plyometric Training.

PubMed

Ramirez-Campillo, Rodrigo; Sanchez-Sanchez, Javier; Gonzalo-Skok, Oliver; Rodríguez-Fernandez, Alejandro; Carretero, Manuel; Nakamura, Fabio Y

2018-01-01

The aim of this study was to compare changes in young soccer player's fitness after traditional bilateral vs. unilateral combined plyometric and strength training. Male athletes were randomly divided in two groups; both received the same training, including strength training for knee extensors and flexors, in addition to horizontal plyometric training drills. The only difference between groups was the mode of drills technique: unilateral (UG; n = 9; age, 17.3 ± 1.1 years) vs. bilateral (TG; n = 9; age, 17.6 ± 0.5 years). One repetition maximum bilateral strength of knee muscle extensors (1RM_KE) and flexors (1RM_KF), change of direction ability (COD), horizontal and vertical jump ability with one (unilateral) and two (bilateral) legs, and limb symmetry index were measured before and after an 8-week in-season intervention period. Some regular soccer drills were replaced by combination of plyometric and strength training drills. Magnitude-based inference statistics were used for between-group and within-group comparisons. Beneficial effects ( p < 0.05) in 1RM_KE, COD, and several test of jumping performance were found in both groups in comparison to pre-test values. The limb symmetry index was not affected in either group. The beneficial changes in 1RM_KE (8.1%; p = 0.074) and 1RM_KF (6.7%; p = 0.004), COD (3.1%; p = 0.149), and bilateral jump performance (from 2.7% [ p = 0.535] to 10.5% [ p = 0.002]) were possible to most likely beneficial in the TG than in the UG. However, unilateral jump performance measures achieved likely to most likely beneficial changes in the UG compared to the TG (from 4.5% [ p = 0.090] to 8.6% [ p = 0.018]). The improvements in jumping ability were specific to the type of jump performed, with greater improvements in unilateral jump performance in the UG and bilateral jump performance in the TG. Therefore, bilateral strength and plyometric training should be complemented with unilateral drills, in order to maximize adaptations.

Effects of recreational soccer on physical fitness and health indices in sedentary healthy and unhealthy subjects

PubMed Central

Chamari, K; Slimani, M; Shephard, RJ; Yousfi, N; Tabka, Z; Bouhlel, E

2016-01-01

Recreational soccer (RS) is becoming a popular alternative to the classical continuous exercise mode used for the improvement of cardiovascular and metabolic fitness in untrained people. The objective of this paper was to conduct a detailed systematic review of the literature, identifying the physiological responses to RS and the training effects of RS on aerobic fitness and health in untrained healthy individuals and clinical patients. PubMed, Google Scholar and ScienceDirect databases were searched using terms related to recreational soccer. Inclusion criteria were randomized controlled trials (RCT) that assessed acute physiological responses to RS or the training effects of RS on physical fitness and health in sedentary, untrained subjects of any age or health status. All studies were assessed for methodological quality using the PEDro scale. Thirty-five articles met the inclusion criteria; seven examined the acute response to RS, and 28 assessed training effects. Clear evidence was found that RS had positive effects on many health-related indices and variables, including VO2max (gains of 7-16%), blood pressure (reductions of 6-13 mmHg), body composition (decreased fat mass and improved indices of bone health), and metabolic and cardiac function. These positive effects were observed in both healthy individuals and clinical patients, irrespective of age or sex. Although this review provides clear evidence of the positive effects of RS on health, most studies had limitations of methodology (an average PEDro score < 6). Furthermore, many of the training studies were from a small number of research groups. Future studies should be extended to other countries and institutions to ensure generality of the results. Regular RS training leads to significant cardiovascular and muscular adaptations and gains of health both in sedentary individuals and clinical patients at all ages, suggesting that RS is a potentially highly motivational method to enhance population health. PMID:27274105

Postural Balance Following Aerobic Fatigue Tests: A Longitudinal Study Among Young Athletes.

PubMed

Steinberg, Nili; Eliakim, Alon; Zaav, Aviva; Pantanowitz, Michal; Halumi, Monder; Eisenstein, Tamir; Meckel, Yoav; Nemet, Dan

2016-01-01

General fatigue can cause aggravation of postural balance, with increased risk for injuries. The present longitudinal study aimed to evaluate the postural balance of young athletes following field aerobic tests throughout 1 year of training. Thirty children from a sports center in Nazareth, participating in a 3 times/week training program (specific to basketball, soccer, or athletic training), were assessed. Postural balance parameters were taken before, immediately after, and 10 min after a 20 m shuttle-run aerobic test, at 3 time points during 1 training year (Start/Y, Mid/Y, and End/Y). Fitness improved at the Mid/Y and End/Y compared to Start/Y. Postural balance significantly deteriorated immediately after the aerobic test and improved significantly in the 10-min testing in all 3 time points, with significant deterioration in the End/Y compared with the Start/Y. In conclusions, postural balance deteriorates immediately after aerobic exercises, and at the end of the year. To better practice drills related to postural balance and possibly to prevent injuries, it is best for young athletes to properly rest immediately following aerobic exercises and to practice postural balance mainly at the beginning and at the middle of the training year.

Methods of the international study on soccer at altitude 3600 m (ISA3600)

PubMed Central

Gore, Christopher J; Aughey, Robert J; Bourdon, Pitre C; Garvican-Lewis, Laura A; Soria, Rudy; Claros, Jesus C Jimenez; Sargent, Charli; Roach, Gregory D; Buchheit, Martin; Simpson, Ben M; Hammond, Kristal; Kley, Marlen; Wachsmuth, Nadine; Pepper, Mark; Edwards, Alistair; Cuenca, Douglas; Vidmar, Tony; Spielvogel, Hilde; Schmidt, Walter F

2013-01-01

Background We describe here the 3-year process underpinning a multinational collaboration to investigate soccer played at high altitude—La Paz, Bolivia (3600 m). There were two main aims: first, to quantify the extent to which running performance would be altered at 3600 m compared with near sea level; and second, to characterise the time course of acclimatisation of running performance and underlying physiology to training and playing at 3600 m. In addition, this project was able to measure the physiological changes and the effect on running performance of altitude-adapted soccer players from 3600 m playing at low altitude. Methods A U20 Bolivian team (‘The Strongest’ from La Paz, n=19) played a series of five games against a U17 team from sea level in Australia (The Joeys, n=20). 2 games were played near sea level (Santa Cruz 430 m) over 5 days and then three games were played in La Paz over the next 12 days. Measures were (1) game and training running performance—including global positioning system (GPS) data on distance travelled and velocity of movement; (2) blood—including haemoglobin mass, blood volume, blood gases and acid–base status; (3) acclimatisation—including resting heart rate variability, perceived altitude sickness, as well as heart rate and perceived exertion responses to a submaximal running test; and (4) sleep patterns. Conclusions Pivotal to the success of the project were the strong professional networks of the collaborators, with most exceeding 10 years, the links of several of the researchers to soccer federations, as well as the interest and support of the two head coaches. PMID:24282214

Comparison of physical performance among Brazilian elite soccer players of different age-categories.

PubMed

Kobal, Ronaldo; Loturco, Irineu; Gil, Saulo; Cal Abad, Cesar C; Cuniyochi, Rogério; Barroso, Renato; Tricoli, Valmor

2016-04-01

The purpose of this study was to compare the physical performance (i.e., strength, power, speed and endurance) between Brazilian elite soccer players from different categories of the same club: professionals (PRO), under-20 (U-20), and under-17 (U-17). Seventy-one soccer players from three categories (PRO=24; U-20=21 and U-17=26) were assessed at the beginning of pre-season. Before the tests, they were familiarized with all experimental procedures. Squat jump (SJ), countermovement jump (CMJ), sprint (10 m/20 m), maximum dynamic strength (1RM), and Yo-Yo intermittent recovery tests level 1 were performed in three non-consecutive sessions. No significant differences were found between the categories for sprint times. The PRO players presented higher outcomes in the 1RM, SJ, CMJ, and Yo-Yo tests than the U-20 and U-17 players (P≤0.05). No significant differences were found between the U-20 and U-17 players in 1RM, and SJ/CMJ heights. The U-20 presented superior performance than the U-17 in the Yo-Yo test (P≤0.05). The findings indicated that PRO performed better than younger players in all assessments, except for the sprint tests. This may have been possible due to the differences in training experience, technical expertise and individual levels of strength/power. However, the absence of differences between the U-20 and U-17 groups highlighted the necessity of developing specific training strategies in order to improve the physical capacities of younger players, throughout the maturation process. Moreover, due to the importance of sprinting in soccer, it is strongly recommended that fitness coaches develop more effective strategies to improve speed ability in professional players.

Muscle Activation During Side-Step Cutting Maneuvers in Male and Female Soccer Athletes

PubMed Central

Hanson, Ashley M; Padua, Darin A; Troy Blackburn, J; Prentice, William E; Hirth, Christopher J

2008-01-01

Context: Female soccer athletes are at greater risk of anterior cruciate ligament (ACL) injury than males. Sex differences in muscle activation may contribute to the increased incidence of ACL injuries in female soccer athletes. Objective: To examine sex differences in lower extremity muscle activation between male and female soccer athletes at the National Collegiate Athletic Association Division I level during 2 side-step cutting maneuvers. Design: Cross-sectional with 1 between-subjects factor (sex) and 2 within-subjects factors (cutting task and phase of contact). Setting: Sports medicine research laboratory. Patients or Other Participants: Twenty males (age = 19.4 ± 1.4 years, height = 176.5 ± 5.5 cm, mass = 74.6 ± 6.0 kg) and 20 females (age = 19.8 ± 1.1 years, height = 165.7 ± 4.3 cm, mass = 62.2 ± 7.2 kg). Intervention(s): In a single testing session, participants performed the running-approach side-step cut and the box-jump side-step cut tasks. Main Outcome Measure(s): Surface electromyographic activity of the rectus femoris, vastus lateralis, medial hamstrings, lateral hamstrings, gluteus medius, and gluteus maximus was recorded for each subject. Separate mixed-model, repeated-measures analysis of variance tests were used to compare the dependent variables across sex during the preparatory and loading contact phases of each cutting task. Results: Females displayed greater vastus lateralis activity and quadriceps to hamstrings coactivation ratios during the preparatory and loading phases, as well as greater gluteus medius activation during the preparatory phase only. No significant differences were noted between the sexes for muscle activation in the other muscles analyzed during each task. Conclusions: The quadriceps-dominant muscle activation pattern observed in recreationally active females is also present in female soccer athletes at the Division I level when compared with similarly trained male soccer athletes. The relationship between increased quadriceps activation and greater incidence of noncontact ACL injury in female soccer athletes versus males requires further study. PMID:18345337

Seasonal Changes in Soccer Players' Body Composition and Dietary Intake Practices.

PubMed

Devlin, Brooke L; Kingsley, Michael; Leveritt, Michael D; Belski, Regina

2017-12-01

Devlin, BL, Kingsley, M, Leveritt, MD, and Belski, R. Seasonal changes in soccer players' body composition and dietary intake practices. J Strength Cond Res 31(12): 3319-3326, 2017-The aims of this study were 2-fold: to determine seasonal changes in dietary intake and body composition in elite soccer players and to evaluate the influence of self-determined individual body composition goals on dietary intake and body composition. This longitudinal, observational study assessed body composition (total mass, fat-free soft tissue mass, and fat mass) using dual-energy x-ray absorptiometry and dietary intake (energy and macronutrients) via multiple-pass 24-hour recalls, at 4 time points over a competitive season in elite soccer players from one professional club in the Australian A-League competition. Self-reported body composition goals were also recorded. Eighteen elite male soccer players took part (25 ± 5 years, 180.5 ± 7.4 cm, 75.6 ± 6.5 kg). Majority (≥67%) reported the goal to maintain weight. Fat-free soft tissue mass increased from the start of preseason (55,278 ± 5,475 g) to the start of competitive season (56,784 ± 5,168 g; p < 0.001), and these gains were maintained until the end of the season. Fat mass decreased over the preseason period (10,072 ± 2,493 g to 8,712 ± 1,432 g; p < 0.001), but increased during the latter part of the competitive season. Dietary intake practices on training days were consistent over time and low compared with sport nutrition recommendations. The self-reported body composition goals did not strongly influence dietary intake practices or changes in body composition. This study has demonstrated that body composition changes over the course of a soccer season are subtle in elite soccer players despite relatively low self-reported intake of energy and carbohydrate.

Effects of Soccer Heading on Brain Structure and Function

PubMed Central

Rodrigues, Ana Carolina; Lasmar, Rodrigo Pace; Caramelli, Paulo

2016-01-01

Soccer is the most popular sport in the world, with more than 265 million players worldwide, including professional and amateur ones. Soccer is unique in comparison to other sports, as it is the only sport in which participants purposely use their head to hit the ball. Heading is considered as an offensive or defensive move whereby the player’s unprotected head is used to deliberately impact the ball and direct it during play. A soccer player can be subjected to an average of 6–12 incidents of heading the ball per competitive game, where the ball reaches high velocities. Moreover, in practice sessions, heading training, which involves heading the ball repeatedly at low velocities, is common. Although the scientific community, as well as the media, has focused on the effects of concussions in contact sports, the role of subconcussive impacts, as it can occur during heading, has recently gained attention, considering that it may represent an additional mechanism of cumulative brain injury. The purpose of this study is to review the existing literature regarding the effects of soccer heading on brain structure and function. Only in the last years, some investigations have addressed the impact of heading on brain structure, by using neuroimaging techniques. Similarly, there have been some recent studies investigating biochemical markers of brain injury in soccer players. There is evidence of association between heading and abnormal brain structure, but the data are still preliminary. Also, some studies have suggested that subconcussive head impacts, as heading, could cause cognitive impairment, whereas others have not corroborated this finding. Questions persist as to whether or not heading is deleterious to cognitive functioning. Further studies, especially with longitudinal designs, are needed to clarify the clinical significance of heading as a cause of brain injury and to identify risk factors. Such investigations might contribute to the establishment of safety guidelines that could help to minimize the risk of possible adverse effects of soccer on brain structure and function. PMID:27047444

Differences in Neuromuscular Strategies Between Landing and Cutting Tasks in Female Basketball and Soccer Athletes

PubMed Central

Cowley, Hanni R; Ford, Kevin R; Myer, Gregory D; Kernozek, Thomas W; Hewett, Timothy E

2006-01-01

Context: High school female athletes are most likely to sustain a serious knee injury during soccer or basketball, 2 sports that often involve a rapid deceleration before a change of direction or while landing from a jump. Objective: To determine if female high school basketball and soccer players show neuromuscular differences during landing and cutting tasks and to examine neuromuscular differences between tasks and between dominant and nondominant sides. Design: A 3-way mixed factorial design investigating the effects of sport (basketball, soccer), task (jumping, cutting), and side (dominant, nondominant). Setting: Laboratory. Patients or Other Participants: Thirty high school female athletes who listed either basketball or soccer as their only sport of participation (basketball: n = 15, age = 15.1 ± 1.7 years, experience = 6.9 ± 2.2 years, height = 165.3 ± 7.9 cm, mass = 61.8 ± 9.3 kg; soccer: n = 15, age = 14.8 ± 0.8 years, experience = 8.8 ± 2.5 years, height = 161.8 ± 4.1 cm, mass = 54.6 ± 7.6 kg). Main Outcome Measure(s): Ground reaction forces, stance time, valgus angles, and valgus moments were assessed during (1) a drop vertical jump with an immediate maximal vertical jump and (2) an immediate side-step cut at a 45° angle. Results: Basketball athletes had greater ground reaction forces (P < .001) and decreased stance time (P < .001) during the drop vertical jump, whereas soccer players had greater ground reaction forces (P <.001) and decreased stance time (P < .001) during the cut. Subjects in both sports had greater valgus angles (initial contact and maximum, P = .02 and P = .012, respectively) during cutting than during the drop vertical jump. Greater valgus moments (P = .006) were noted on the dominant side during cutting. Conclusions: Our subjects demonstrated differences in ground reaction forces and stance times during 2 movements associated with noncontact anterior cruciate ligament injuries. Knee valgus moment and angle were significantly influenced by the type of movement performed. Sport-specific neuromuscular training may be warranted, with basketball players focusing on jumping and landing and soccer players focusing on unanticipated cutting maneuvers. PMID:16619097

Groin Problems in Male Soccer Players Are More Common Than Previously Reported.

PubMed

Harøy, Joar; Clarsen, Ben; Thorborg, Kristian; Hölmich, Per; Bahr, Roald; Andersen, Thor Einar

2017-05-01

The majority of surveillance studies in soccer have used a time-loss injury definition, and many groin problems result from overuse, leading to gradually increasing pain and/or reduced performance without necessarily causing an absence from soccer training or match play. Thus, the magnitude of groin problems in soccer has probably been underestimated in previous studies based on traditional injury surveillance methods. To investigate the prevalence of groin problems among soccer players of both sexes and among male soccer players at different levels of play through a new surveillance method developed to capture acute and overuse problems. Descriptive epidemiology study. We registered groin problems during a 6-week period of match congestion using the Oslo Sports Trauma Research Center Overuse Injury Questionnaire. A total of 240 players from 15 teams across different levels of play and from both sexes were included, and they responded to the weekly questionnaire. We calculated the average weekly prevalence of all groin problems and substantial groin problems. Of the 240 players, 112 male players (59%) and 20 female players (45%) reported at least 1 episode of groin problems. The average weekly prevalence of any groin problem and substantial groin problem for all male players was 29% (range, 23%-32% across different levels) and 10% (7%-13%), respectively. Elite male players had an increased risk of experiencing groin problems (odds ratio: 3.1, 95% CI: 1.5-6.4, P = .03) compared with elite female players. There was no difference in the risk of experiencing groin problems among elite, subelite, and amateur male players. For substantial problems, there was no difference between elite male and elite female players or among levels of play for senior male soccer players. We found a high prevalence of groin problems among male soccer players during a period with match congestion. Time-loss definition as used in previous injury surveillance studies captured only one-third of the male groin problems registered with the new method. Elite male players had 3 times' higher risk of reporting groin problems as compared with elite female players, while playing level did not influence the risk of reporting a groin problem among males.

Risk factors for lower extremity injuries in elite female soccer players.

PubMed

Nilstad, Agnethe; Andersen, Thor Einar; Bahr, Roald; Holme, Ingar; Steffen, Kathrin

2014-04-01

The incidence of lower extremity injuries in female soccer players is high, but the risk factors for injuries are unknown. To investigate risk factors for lower extremity injuries in elite female soccer players. Cohort study; Level of evidence, 3. Players in the Norwegian elite female soccer league (N = 12 teams) participated in baseline screening tests before the 2009 competitive soccer season. The screening included tests assessing maximal lower extremity strength, dynamic balance, knee valgus angles in a drop-jump landing, knee joint laxity, generalized joint laxity, and foot pronation. Also included was a questionnaire to collect information on demographic data, elite-level experience, and injury history. Time-loss injuries and exposure in training and matches were recorded prospectively in the subsequent soccer season using weekly text messaging. Players reporting an injury were contacted to collect data regarding injury circumstances. Univariate and multivariate regression analyses were used to calculate odds ratios (ORs) and 95% confidence intervals (CIs) for ±1 standard deviation of change. In total, 173 players underwent complete screening tests and registration of injuries and exposure throughout the season. A total of 171 injuries in 107 players (62%) were recorded; ligament and muscle injuries were the most frequent. Multivariate analyses showed that a greater body mass index (BMI) (OR, 1.51; 95% CI, 1.21-1.90; P = .001) was the only factor significantly associated with new lower extremity injuries. A greater BMI was associated with new thigh injuries (OR, 1.51; 95% CI, 1.08-2.11; P = .01), a lower knee valgus angle in a drop-jump landing was associated with new ankle injuries (OR, 0.64; 95% CI, 0.41-1.00; P = .04), and a previous knee injury was associated with new lower leg and foot injuries (OR, 3.57; 95% CI, 1.27-9.99; P = .02), whereas none of the factors investigated influenced the risk of new knee injuries. A greater BMI was associated with lower extremity injuries in elite female soccer players. Increased knowledge on risk factors for lower extremity injuries enables more targeted prevention strategies with the aim of reducing injury rates in female soccer players.

Postural Performance and Strategy in the Unipedal Stance of Soccer Players at Different Levels of Competition

PubMed Central

Paillard, Thierry; Noé, Frédéric; Rivière, Terence; Marion, Vincent; Montoya, Richard; Dupui, Philippe

2006-01-01

Context: Sport training enhances the ability to use somatosensory and otolithic information, which improves postural capabilities. Postural changes are different according to the sport practiced, but few authors have analyzed subjects' postural performances to discriminate the expertise level among highly skilled athletes within a specific discipline. Objective: To compare the postural performance and the postural strategy between soccer players at different levels of competition (national and regional). Design: Repeated measures with 1 between-groups factor (level of competition: national or regional) and 1 within-groups factor (vision: eyes open or eyes closed). Dependent variables were center-of-pressure surface area and velocity; total spectral energy; and percentage of low-, medium-, and high-frequency band. Setting: Sports performance laboratory. Patients or Other Participants: Fifteen national male soccer players (age = 24 ± 3 years, height = 179 ± 5 cm, mass = 72 ± 3 kg) and 15 regional male soccer players (age = 23 ± 3 years, height = 174 ± 4 cm, mass = 68 ± 5 kg) participated in the study. Intervention(s): The subjects performed posturographic tests with eyes open and closed. Main Outcome Measure(s): While subjects performed static and dynamic posturographic tests, we measured the center of foot pressure on a force platform. Spatiotemporal center-of-pressure measurements were used to evaluate the postural performance, and a frequency analysis of the center-of-pressure excursions (fast Fourier transform) was conducted to estimate the postural strategy. Results: Within a laboratory task, national soccer players produced better postural performances than regional players and had a different postural strategy. The national players were more stable than the regional players and used proprioception and vision information differently. Conclusions: In the test conditions specific to playing soccer, level of playing experience influenced postural control performance measures and strategies. PMID:16791302

Postural performance and strategy in the unipedal stance of soccer players at different levels of competition.

PubMed

Paillard, Thierry; Noé, Frédéric; Rivière, Terence; Marion, Vincent; Montoya, Richard; Dupui, Philippe

2006-01-01

Sport training enhances the ability to use somatosensory and otolithic information, which improves postural capabilities. Postural changes are different according to the sport practiced, but few authors have analyzed subjects' postural performances to discriminate the expertise level among highly skilled athletes within a specific discipline. To compare the postural performance and the postural strategy between soccer players at different levels of competition (national and regional). Repeated measures with 1 between-groups factor (level of competition: national or regional) and 1 within-groups factor (vision: eyes open or eyes closed). Dependent variables were center-of-pressure surface area and velocity; total spectral energy; and percentage of low-, medium-, and high-frequency band. Sports performance laboratory. Fifteen national male soccer players (age = 24 +/- 3 years, height = 179 +/- 5 cm, mass = 72 +/- 3 kg) and 15 regional male soccer players (age = 23 +/- 3 years, height = 174 +/- 4 cm, mass = 68 +/- 5 kg) participated in the study. The subjects performed posturographic tests with eyes open and closed. While subjects performed static and dynamic posturographic tests, we measured the center of foot pressure on a force platform. Spatiotemporal center-of-pressure measurements were used to evaluate the postural performance, and a frequency analysis of the center-of-pressure excursions (fast Fourier transform) was conducted to estimate the postural strategy. Within a laboratory task, national soccer players produced better postural performances than regional players and had a different postural strategy. The national players were more stable than the regional players and used proprioception and vision information differently. In the test conditions specific to playing soccer, level of playing experience influenced postural control performance measures and strategies.

Effect of ACTN3 gene on strength and endurance in soccer players.

PubMed

Pimenta, Eduardo M; Coelho, Daniel B; Veneroso, Christiano E; Barros Coelho, Ering J; Cruz, Izinara R; Morandi, Rodrigo F; De A Pussieldi, Guilherme; Carvalho, Maria R S; Garcia, Emerson S; De Paz Fernández, José A

2013-12-01

Sports efficiency in activities in which strength and speed are the determining factors has been associated to the ACTN3 gene, which is responsible for the expression of α-actinin-3. Soccer is a mainly aerobic sport because of its long duration, but the acute actions that define the game demand a lot of strength and speed. The purpose of the present study was to compare the performance capacity of soccer players with different genotype groups of ACTN3 (XX, RX, and RR) in strength, speed, and endurance tests. Two hundred professional players of Brazilian soccer first division teams participated in this study. Speed, jump, and endurance test results were compared with the polymorphisms of the ACTN3 gene. It was noticed that RR individuals spent less time to run a 10-m path, compared with XX individuals (p < 0.05). The RR individuals also presented lower time rates at the 20- and 30-m path, compared with RX and XX individuals (p < 0.05). In jump tests, RR individuals presented higher rates, compared with RX and XX individuals (p < 0.05). As for aerobic tests, the XX individuals presented higher rates of V[Combining Dot Above]O2 max, compared with the RR group (p < 0.05), and did not differ from the RX group. The main conclusion of this study is that soccer players of genotype ACTN3/RR are the fastest in short distances and present higher jump potential. ACTN3/XX individuals presented the highest aerobic capacity. These findings can be used in training load adjustment and can influence the development of tactical schemes in soccer matches.

Computer-based coding of free-text job descriptions to efficiently identify occupations in epidemiological studies

PubMed Central

Russ, Daniel E.; Ho, Kwan-Yuet; Colt, Joanne S.; Armenti, Karla R.; Baris, Dalsu; Chow, Wong-Ho; Davis, Faith; Johnson, Alison; Purdue, Mark P.; Karagas, Margaret R.; Schwartz, Kendra; Schwenn, Molly; Silverman, Debra T.; Johnson, Calvin A.; Friesen, Melissa C.

2016-01-01

Background Mapping job titles to standardized occupation classification (SOC) codes is an important step in identifying occupational risk factors in epidemiologic studies. Because manual coding is time-consuming and has moderate reliability, we developed an algorithm called SOCcer (Standardized Occupation Coding for Computer-assisted Epidemiologic Research) to assign SOC-2010 codes based on free-text job description components. Methods Job title and task-based classifiers were developed by comparing job descriptions to multiple sources linking job and task descriptions to SOC codes. An industry-based classifier was developed based on the SOC prevalence within an industry. These classifiers were used in a logistic model trained using 14,983 jobs with expert-assigned SOC codes to obtain empirical weights for an algorithm that scored each SOC/job description. We assigned the highest scoring SOC code to each job. SOCcer was validated in two occupational data sources by comparing SOC codes obtained from SOCcer to expert assigned SOC codes and lead exposure estimates obtained by linking SOC codes to a job-exposure matrix. Results For 11,991 case-control study jobs, SOCcer-assigned codes agreed with 44.5% and 76.3% of manually assigned codes at the 6- and 2-digit level, respectively. Agreement increased with the score, providing a mechanism to identify assignments needing review. Good agreement was observed between lead estimates based on SOCcer and manual SOC assignments (kappa: 0.6–0.8). Poorer performance was observed for inspection job descriptions, which included abbreviations and worksite-specific terminology. Conclusions Although some manual coding will remain necessary, using SOCcer may improve the efficiency of incorporating occupation into large-scale epidemiologic studies. PMID:27102331

Comparison of tensiomyographic neuromuscular characteristics between muscles of the dominant and non-dominant lower extremity in male soccer players.

PubMed

Alvarez-Diaz, Pedro; Alentorn-Geli, Eduard; Ramon, Silvia; Marin, Miguel; Steinbacher, Gilbert; Rius, Marta; Seijas, Roberto; Ballester, Jordi; Cugat, Ramon

2016-07-01

Tensiomyography (TMG) has been used to assess neuromuscular characteristics of muscles of the lower extremity in soccer players. However, the effects of lower extremity dominance on TMG characteristics in this population have not been reported to date. The purpose of this study was to compare the TMG neuromuscular characteristics between the dominant and non-dominant lower extremity in male soccer players. Thirty-eight consecutive healthy male soccer players underwent resting TMG assessment of vastus medialis (VM), vastus lateralis (VL), rectus femoris (RF), semitendinosus (ST), biceps femoris (BF), gastrocnemius medialis (GM), and gastrocnemius lateralis (GL) in both lower extremities. The maximal displacement, delay time, contraction time, sustained time, and half-relaxation time were obtained and compared between both sides. There were no significant differences in the vast majority of the TMG parameters between both lower extremities. The dominant side demonstrated higher VM contraction time (p = 0.008), RF sustained time (p = 0.009), RF half-relaxation time (p = 0.01), and BF sustained time (p = 0.04), but lower VL contraction time (p = 0.03) and VL delay time (p = 0.02) compared to the non-dominant side. In general, TMG-assessed neuromuscular characteristics of the VM, VL, RF, ST, BF, GM, and GL were not affected by lower extremity dominance in male soccer players. Therefore, there is no need to assess both sides when using TMG to monitor the response to training or muscles at risk of injury in soccer players unless there is a specific reason. Prognostic study, Level II.

MRI of the knees in asymptomatic adolescent soccer players: A case-control study.

PubMed

Matiotti, Simone B; Soder, Ricardo B; Becker, Rafaela G; Santos, Francisco S; Baldisserotto, Matteo

2017-01-01

To determine the range of asymptomatic abnormal findings in adolescent soccer players at 3.0T MRI of the knee. In all, 87 knees of asymptomatic 14-17-year-old male adolescents were evaluated at 3T, using a standardized examination protocol comprising four sequences: two fat-suppressed T 2 -weighted fast spin-echo sequences (T 2 FSE), in the sagittal (repetition time / echo time [TR/TE], 5.300/71, echo train length [ETL] 17) and coronal planes (TR/TE, 4234/70, ETL 17), one fat-suppressed proton density (PD) sequence in the axial plane (TR/TE, 2.467/40, ETL 9), and one T 1 -weighted spin-echo (T 1 SE) sequence in the sagittal plane (TR/TE, 684/12.5). Soccer players (46 knees) were paired with controls (41 knees) by age and weight. Bone marrow, articular cartilage, meniscus, tendons, ligaments, fat pad abnormalities, and joint fluid were assessed. One or more abnormalities were detected in 31 knees (67.4%) in the soccer player group, compared to 20 knees (48.8%) in the control group. The prevalence of bone marrow edema was higher in the soccer group (19 knees, 41.3%) than in the control group (3 knees, 7.3%), P = 0.001. Other abnormalities found in this sample (joint effusion, cartilage lesions, tendinopathy, ganglion cysts, and infrapatellar fat pat edema) were not significantly different between the two study groups. Asymptomatic adolescents had a high prevalence of abnormal findings on knee imaging, especially bone marrow edema. This prevalence was higher among soccer players. 4 J. Magn. Reson. Imaging 2017;45:59-65. © 2016 International Society for Magnetic Resonance in Medicine.

Young male soccer players exhibit additional bone mineral acquisition during the peripubertal period: 1-year longitudinal study.

PubMed

Zouch, Mohamed; Vico, Laurence; Frere, Delphine; Tabka, Zouhair; Alexandre, Christian

2014-01-01

The aim of this study was to determine whether soccer could have different bone benefits in prepubescent and pubescent boys. We investigated 76 boys aged 10 to 13 years during a 1-year study. All boys were prepubescent at the beginning of the study (T0); pubescent status was determined by a complete 24-h urine hormonal assay of FSH-LH, with LH ≤ 0.31 IU/24 h and FSH ≤ 2.19 IU/24 h corresponding to prepubescent Tanner stage I and with 0.31 < LH < 0.95 IU/24 h and 1.57 < FSH < 3.77 IU/24 h corresponding to pubescent Tanner stage II. At the end of the study (T1), 35 boys remained prepubescent (22 soccer players (F1) and 13 controls (C1)), and 41 boys had entered puberty (26 soccer players (F2) and 15 controls (C2)). Soccer players completed 2 to 5 h of training plus one competition game per week during the school year, and controls only had physical education at school. Bone mineral content (BMC) was measured at T0 and T1 by DPX in the lumbar spine, total hip, and whole body (WB) for a comparison between soccer players and controls. At T0, no BMC difference was found between F1 and C1, but BMC was higher in F2 than C2 in WB and weight-bearing sites. At T1, BMC was higher in WB and weight-bearing sites in both F1 and F2 compared to their respective controls. Between T0 and T1, soccer induced a BMC gain at weight-bearing sites in both F1 and F2 compared to C1 and C2, respectively. The soccer-related bone gain was greater in WB and weight-bearing (the lumbar spine, total hip, and supporting leg) and non-weight-bearing bones (dominant arm and nondominant arm) in boys who became pubescent than in boys who remained prepubescent. In conclusion, 1-year study in young male soccer players demonstrates that the process of bone accretion at the very early phase of puberty is more intensely stimulated by the combination of physical exercise and sexual impregnation than by one of these factors alone.

An assessment of the nutritional intake of soccer referees.

PubMed

Martínez Reñón, Cristian; Collado, Pilar S

2015-01-01

The present study aims to analyze the eating habits and attitudes of a group of soccer referees and linesmen. A nutritional study was undertaken of thirty-five soccer referees (aged between 18 and 50) refereeing at different levels, from the Spanish national third division down to the provincial second division. Through the use of a 3-day food diary and 24-hour recall, this study analyzed the intake and distribution of macro- and micro-nutrients and of dietary fiber consumed on different types of day (normal, training, and match days). There were no significant differences in calorie intake related to the three types of day (normal, training, and match days). This was true both of overall amounts (2371.1 kcal, 2479.7 kcal, and 2368.4 kcal, respectively) and amounts per unit of body weight (32.4 kcal/kg, 33.9 kcal/kg, and 32.4 kcal/kg, respectively). In respect of macro-nutrient intake, more specifically carbohydrates, the subjects consumed a diet with an insufficient amount of carbohydrates: 279 g, as against the 371 g (REC1) or 540 g (REC2) recommended according to physical activity levels. Slight increases were observed on game days, but were not statistically significant. Consideration of micro-nutrients showed that the quantities of three vitamins (B6, B12, and C) consumed were above the recommended amounts. However, this was not an issue, since the figures related to water-soluble vitamins. Finally, the amounts of minerals (Ca, Mg, and Fe) and fiber consumed were close to recommended values, regardless of the type of day being considered. This study found that the group of referees investigated consumed a diet that did not have sufficient calories from carbohydrates, in view of their occupation. This poor nutritional status might interfere with the development of their sporting performance and ultimately increase the risk of injury. This implies a need to design and implement a diet and to introduce educational programs on nutrition for these sportspeople.

Linking the Revised National Standards to Teaching Games for Understanding: An Eighth-Grade Soccer Example

ERIC Educational Resources Information Center

Parkes, Craig; Subramaniam, Prithwi Raj

2015-01-01

In the United States it is estimated that over 3 million children and young people currently participate in youth soccer programs. This number has the potential to increase following a surge of interest in the U.S. Men's National Team World Cup performance in Brazil in 2014, and the U.S. Women's National Team World Cup win in Canada in 2015. This…

Heavy episodic drinking and soccer practice among high school students in Brazil: the contextual aspects of this relationship.

PubMed

Bedendo, André; Opaleye, Emérita S; Andrade, André Luiz Monezi; Noto, Ana Regina

2013-03-20

Heavy episodic drinking (HED) (consumption of five or more drinks on the same occasion) among adolescents is related to several problems and partaking in sport or physical activities has been suggested as an option to prevent or reduce alcohol consumption among this population. The aim of this study was to investigate the relationship between soccer practice and heavy episodic drinking among high school students from Brazil. Data were obtained from a cross-sectional study among a representative sample of public and private high school students from all Brazilian state capitals (N=19,132). Only students aged from 14 to 18 who reported having taken part in soccer practice, other team sports or non-practicing sports in the last month were included. Characteristics of sport practice (frequency and motivation) and HED in the last month (type of drink; where and with whom they drank; frequency of HED) were also considered. Regression models were controlled for sociodemographic variables. For all groups studied most of the students reported drinking beer, with friends and at nightclubs or bars. Soccer practice was associated to HED when compared to non-practicing sports and to other team sports. Compared to other team sports, playing soccer for pleasure or profession, but not for keep fit or health reasons, were more associated to HED. Frequency of soccer practice from 1 to 5 days per month and 20 or more days per month, but not from 6 to 19 days per month, were also more associated to HED. The relationship between soccer and HED appears to be particularly stronger than in other team sports among adolescents in Brazil. Induced sociability of team sports practice cannot be assumed as the main reason for HED among soccer players. Possibly these results reflect the importance of a strong cultural association between soccer and beer in Brazil and these findings should be integrated to future prevention or intervention programs.

Heavy episodic drinking and soccer practice among high school students in Brazil: the contextual aspects of this relationship

PubMed Central

2013-01-01

Background Heavy episodic drinking (HED) (consumption of five or more drinks on the same occasion) among adolescents is related to several problems and partaking in sport or physical activities has been suggested as an option to prevent or reduce alcohol consumption among this population. The aim of this study was to investigate the relationship between soccer practice and heavy episodic drinking among high school students from Brazil. Methods Data were obtained from a cross-sectional study among a representative sample of public and private high school students from all Brazilian state capitals (N=19,132). Only students aged from 14 to 18 who reported having taken part in soccer practice, other team sports or non-practicing sports in the last month were included. Characteristics of sport practice (frequency and motivation) and HED in the last month (type of drink; where and with whom they drank; frequency of HED) were also considered. Regression models were controlled for sociodemographic variables. Results For all groups studied most of the students reported drinking beer, with friends and at nightclubs or bars. Soccer practice was associated to HED when compared to non-practicing sports and to other team sports. Compared to other team sports, playing soccer for pleasure or profession, but not for keep fit or health reasons, were more associated to HED. Frequency of soccer practice from 1 to 5 days per month and 20 or more days per month, but not from 6 to 19 days per month, were also more associated to HED. Conclusions The relationship between soccer and HED appears to be particularly stronger than in other team sports among adolescents in Brazil. Induced sociability of team sports practice cannot be assumed as the main reason for HED among soccer players. Possibly these results reflect the importance of a strong cultural association between soccer and beer in Brazil and these findings should be integrated to future prevention or intervention programs. PMID:23514566

Different loading schemes in power training during the preseason promote similar performance improvements in Brazilian elite soccer players.

PubMed

Loturco, Irineu; Ugrinowitsch, Carlos; Tricoli, Valmor; Pivetti, Bruno; Roschel, Hamilton

2013-07-01

The present study investigated the effects of 2 different power training loading schemes in Brazilian elite soccer players. Thirty-two players participated in the study. Maximum dynamic strength (1RM) was evaluated before (B), at midpoint (i.e., after 3 weeks; T1), and after 6 weeks (T2) of a preseason strength/power training. Muscle power, jumping, and sprinting performance were evaluated at B and T2. Players were randomly allocated to 1 of 2 training groups: velocity-based (VEL: n = 16; age, 19.18 ± 0.72 years; height, 173 ± 6 cm; body mass, 72.7 ± 5.8 kg) or intensity-based (INT: n = 16; age, 19.11 ± 0.7 years; height, 172 ± 4.5 cm; body mass, 71.8 ± 4.6 kg). After the individual determination of the optimal power load, both groups completed a 3-week traditional strength training period. Afterward, the VEL group performed 3 weeks of power-oriented training with increasing velocity and decreasing intensity (from 60 to 30% 1RM) throughout the training period, whereas the INT group increased the training intensity (from 30 to 60% 1RM) and thus decreased movement velocity throughout the power-oriented training period. Both groups used loads within ±15% (ranging from 30 to 60% 1RM) of the measured optimal power load (i.e., 45.2 ± 3.0% 1RM). Similar 1RM gains were observed in both groups at T1 (VEL: 9.2%; INT: 11.0%) and T2 (VEL: 19.8%; INT: 22.1%). The 2 groups also presented significant improvements (within-group comparisons) in all of the variables. However, no between-group differences were detected. Mean power in the back squat (VEL: 18.5%; INT: 20.4%) and mean propulsive power in the jump squat (VEL: 29.1%; INT: 31.0%) were similarly improved at T2. The 10-m sprint (VEL: -4.3%; INT: -1.6%), jump squat (VEL: 7.1%; INT: 4.5%), and countermovement jump (VEL: 6.7%; INT: 6.9%) were also improved in both groups at T2. Curiously, the 30-m sprint time (VEL: -0.8%; INT: -0.1%) did not significantly improve for both groups. In summary, our data suggest that male professional soccer players can achieve improvements in strength- and power-related abilities as a result of 6 weeks of power-oriented training during the preseason. Furthermore, similar performance improvements are observed when training intensity manipulation occurs around only a small range within the optimal power training load.

Neuromuscular training improves performance and lower-extremity biomechanics in female athletes.

PubMed

Myer, Gregory D; Ford, Kevin R; Palumbo, Joseph P; Hewett, Timothy E

2005-02-01

The purpose of this study was to examine the effects of a comprehensive neuromuscular training program on measures of performance and lower-extremity movement biomechanics in female athletes. The hypothesis was that significant improvements in measures of performance would be demonstrated concomitant with improved biomechanical measures related to anterior cruciate ligament injury risk. Forty-one female basketball, soccer, and volleyball players (age, 15.3 +/- 0.9 years; weight, 64.8 +/- 9.96 kg; height, 171.2 +/- 7.21 cm) underwent 6 weeks of training that included 4 main components (plyometric and movement, core strengthening and balance, resistance training, and speed training). Twelve age-, height-, and weight-matched controls underwent the same testing protocol twice 6 weeks apart. Trained athletes demonstrated increased predicted 1 repetition maximum squat (92%) and bench press (20%). Right and left single-leg hop distance increased 10.39 cm and 8.53 cm, respectively, and vertical jump also increased from 39.9 +/- 0.9 cm to 43.2 +/- 1.1 cm with training. Speed in a 9.1-m sprint improved from 1.80 +/- 0.02 seconds to 1.73 +/- 0.01 seconds. Pre- and posttest 3-dimensional motion analysis demonstrated increased knee flexion-extension range of motion during the landing phase of a vertical jump (right, 71.9 +/- 1.4 degrees to 76.9 +/- 1.4 degrees ; left, 71.3 +/- 1.5 degrees to 77.3 +/- 1.4 degrees ). Training decreased knee valgus (28%) and varus (38%) torques. Control subjects did not demonstrate significant alterations during the 6-week interval. The results of this study support the hypothesis that the combination of multiple-injury prevention-training components into a comprehensive program improves measures of performance and movement biomechanics.

Agility and change of direction in soccer: differences according to the player ages.

PubMed

Fiorilli, Giovanni; Mitrotasios, Michalis; Iuliano, Enzo; Pistone, Eugenio M; Aquino, Giovanna; Calcagno, Giuseppe; DI Cagno, Alessandra

2017-12-01

The goal of this study was to compare the changes of direction speed (CODS) and reactive agility (RA) in soccer players of different ages, in order to optimize the best training of these skills. One hundred eighty-seven players, divided into bi-annual age-groups, U12, U14, U16 and U18, performed two tests: Y-Agility Test, carried out in planned and reactive mode (Y-PLAN and Y-REAC) and Illinois for Change of Direction Test (ICODT). Difference between Y-REAC minus Y-PLAN represents the index of reactivity (REAC-INDEX). MANOVA showed significant differences among groups (F3,182=14.591; P<0.01; η2p=0.244). Y-PLAN showed significant differences only between U12 and the other groups (P<0.01). ICODT results were significantly different between the groups U12 and U14 and the other groups (P<0.01). Significant Pearson's correlations between Y-TEST and ICODT, for the three categories of young players (0.398 P<0.05; 0.615 P<0.01; 0.608 P<0.01 respectively), were found, whereas no significant correlation was found in U18 group. The best performance of Y-PLAN and ICODT, through age, depends on physical skill level, whereas the best RA results depend on technique and experience that help the players to use anticipatory skill. The high correlations between CODS and RA performances, differently than adult athletes, suggest that an effective work program for young players may include RA and CODS training at the same time.

A comparison of the physiological profiles of elite Gaelic footballers, hurlers, and soccer players

PubMed Central

McIntyre, M

2005-01-01

Background: Gaelic football, soccer, and hurling are prominent field games in Ireland and involve participants undertaking a variety of playing tasks and skills which place various physiological demands on the participants. The aim of this study was to evaluate and compare the mid-season physiological profiles of elite players. Methods: Physiological assessment was carried out on 29 inter-county Gaelic footballers, 30 inter-county hurlers, and 21 League of Ireland soccer players. Results: Significant differences were reported for % body fat (p<0.05), aerobic capacity (p<0.05), flexibility (p<0.05), upper body strength (p<0.05), upper body strength endurance (p<0.05), abdominal endurance (p<0.05), and speed endurance (p<0.05), while there were no differences recorded for height, weight, or speed levels. A relatively heterogeneous body size is evident for all three sports. Soccer players had lower body fat levels, greater aerobic capacity, greater strength endurance, and greater flexibility compared to both Gaelic footballers and hurlers, possibly due to specific training and conditioning programmes or physical adaptation to match play The greater strength of both Gaelic footballers and hurlers and the superior speed endurance levels of Gaelic footballers also reflect the physical nature of the sports. Similar speed levels amongst all three sports reflect the importance of speed for performance. Conclusions: The various physiological attributes for Gaelic football, soccer, and hurling reflect the physical requirements for success and participation in each of these field games. PMID:15976166

Big data and tactical analysis in elite soccer: future challenges and opportunities for sports science.

PubMed

Rein, Robert; Memmert, Daniel

2016-01-01

Until recently tactical analysis in elite soccer were based on observational data using variables which discard most contextual information. Analyses of team tactics require however detailed data from various sources including technical skill, individual physiological performance, and team formations among others to represent the complex processes underlying team tactical behavior. Accordingly, little is known about how these different factors influence team tactical behavior in elite soccer. In parts, this has also been due to the lack of available data. Increasingly however, detailed game logs obtained through next-generation tracking technologies in addition to physiological training data collected through novel miniature sensor technologies have become available for research. This leads however to the opposite problem where the shear amount of data becomes an obstacle in itself as methodological guidelines as well as theoretical modelling of tactical decision making in team sports is lacking. The present paper discusses how big data and modern machine learning technologies may help to address these issues and aid in developing a theoretical model for tactical decision making in team sports. As experience from medical applications show, significant organizational obstacles regarding data governance and access to technologies must be overcome first. The present work discusses these issues with respect to tactical analyses in elite soccer and propose a technological stack which aims to introduce big data technologies into elite soccer research. The proposed approach could also serve as a guideline for other sports science domains as increasing data size is becoming a wide-spread phenomenon.

Monitoring of Post-match Fatigue in Professional Soccer: Welcome to the Real World.

PubMed

Carling, Christopher; Lacome, Mathieu; McCall, Alan; Dupont, Gregory; Le Gall, Franck; Simpson, Ben; Buchheit, Martin

2018-05-08

Participation in soccer match-play leads to acute and transient subjective, biochemical, metabolic and physical disturbances in players over subsequent hours and days. Inadequate time for rest and regeneration between matches can expose players to the risk of training and competing whilst not entirely recovered. In professional soccer, contemporary competitive schedules can require teams to compete in excess of 60 matches over the course of the season with periods of fixture congestion occurring, prompting much attention from researchers and practitioners to the monitoring of fatigue and readiness to play. A comprehensive body of research has investigated post-match acute and residual fatigue responses. Yet the relevance of the research for professional soccer contexts is debatable, notably in relation to the study populations and designs employed. Monitoring can indeed be invasive, expensive, time inefficient, and difficult to perform routinely and simultaneously in a large squad of regularly competing players. Uncertainty also exists regarding the meaningfulness and interpretation of changes in fatigue response values and their functional relevance, and practical applicability in the field. The real-world need and cost-benefit of monitoring must be carefully weighed up. In relation to professional soccer contexts, this opinion paper intends to (1) debate the need for post-match fatigue monitoring; (2) critique the real-world relevance of the current research literature; (3) discuss the practical burden relating to measurement tools and protocols, and the collection, interpretation and application of data in the field; and (4) propose future research perspectives.

Shoe and field surface risk factors for acute lower extremity injuries among female youth soccer players

PubMed Central

O'Kane, John W.; Gray, Kristen E.; Levy, Marni R.; Neradilek, Moni; Tencer, Allan F.; Polissar, Nayak L.; Schiff, Melissa A.

2015-01-01

Objective Describe acute lower extremity injuries and evaluate extrinsic risk factors in female youth soccer Design Nested case-control study Setting Youth soccer clubs in Washington State, USA. Participants Female soccer players (N= 351) ages 11 to 15 years randomly selected from 4 soccer clubs from which 83% of their players were enrolled with complete follow-up for 92% of players. Interventions Injured players were interviewed regarding injury, field surface, shoe type, and position. Uninjured controls, matched on game or practice session, were also interviewed. Main Outcome Measures The association between risk factors and acute lower extremity injury using logistic regression to estimate odds ratios (OR) and 95% confidence intervals (CI). Results One hundred seventy-three acute lower extremity injuries occurred involving primarily the ankle (39.3%), knee (24.9%), and thigh (11.0%). Over half (52.9%) recovered within 1 week, while 30.2% lasted beyond 2 weeks. During practices, those injured were approximately 3-fold ( OR 2.83, 95% CI 1.49-5.31) more likely to play on grass than artificial turf and 2.4-fold (95% CI 1.03-5.96) more likely to wear cleats on grass than other shoe and surface combinations. During games injured players were 89% (95% CI 1.03-4.17) more likely to play defender compared to forward. Conclusions Half of the acute lower extremity injuries affected the ankle or knee. Grass surface and wearing cleats on grass increased training injuries. PMID:26327288

Isokinetic imbalance of adductor-abductor hip muscles in professional soccer players with chronic adductor-related groin pain.

PubMed

Belhaj, K; Meftah, S; Mahir, L; Lmidmani, F; Elfatimi, A

2016-11-01

This study aims to compare the isokinetic profile of hip abductor and adductor muscle groups between soccer players suffering from chronic adductor-related groin pain (ARGP), soccer players without ARGP and healthy volunteers from general population. Study included 36 male professional soccer players, who were randomly selected and followed-up over two years. Of the 21 soccer players eligible to participate in the study, 9 players went on to develop chronic ARGP and 12 players did not. Ten healthy male volunteers were randomly selected from the general population as a control group. Comparison between the abductor and adductor muscle peak torques for players with and without chronic ARGP found a statistically significant difference on the dominant and non-dominant sides (p < .005), with the abductor muscle significantly stronger than the adductor muscle. In the group of healthy volunteers, the adductor muscle groups were significantly stronger than the abductor muscle groups on both dominant and non-dominant sides (p < .05). For the group of players who had developed chronic ARGP, abductor-adductor torque ratios were significantly higher on the affected side (p = .008). The adductor muscle strength was also significantly decreased on the affected side. This imbalance appears to be a risk factor for adductor-related groin injury. Therefore, restoring the correct relationship between these two agonist and antagonist hip muscles may be an important preventative measure that should be a primary concern of training and rehabilitation programmes.

Congenital Adrenal Hyperplasia in an Elite Female Soccer Player; What Sports Medicine Clinicians Should Know about This?

PubMed

Angoorani, Hooman; Haratian, Zohreh; Halabchi, Farzin

2012-09-01

Congenital Adrenal Hyperplasia (CAH) refers to a group of congenital conditions characterized by disordered cortisol synthesis. The correlation between CAH and sports performance has been less studied before and there is very limited information regarding the impacts of this congenital disease on sports performance. Probably, there are some limitations for patients who suffer from CAH in sports, but at the same time, they may enjoy some advantage due to the probable effect of endogenous hyperandrogenism on their exercise performance. The case is a 14 - year old girl with male phenotype who is a known case of congenital adrenal hyperplasia. She plays in the women's national soccer team of under 16. She has been in the first division league of indoor soccer for 4 years and was also selected in the preparation training camp of women's football team for Singapore's youth Olympic Games. Her illness and dependence on corticosteroid have caused some concerns for her participation in the international competitions of women. However, following consultations with the Therapeutic Use Exemption (TUE) Committee of games organization, she received TUE to use corticosteroid only within the games period. Despite all her problems, she is now playing in the Second Division League of indoor soccer. A female adolescent with CAH may compete at the high level of outdoor and indoor soccer. However, there are many questions regarding the advantages and disadvantages of this congenital disorder and its treatment on sports related issues.

Lower reinjury rate with a coach-controlled rehabilitation program in amateur male soccer: a randomized controlled trial.

PubMed

Hägglund, Martin; Waldén, Markus; Ekstrand, Jan

2007-09-01

Soccer injuries are common, and athletes returning to play after injury are especially at risk. Few studies have investigated how to prevent reinjury. The rate of reinjury is reduced using a coach-controlled rehabilitation program. Randomized controlled trial; Level of evidence, 1. Twenty-four male amateur soccer teams were randomized into an intervention (n = 282) and control group (n = 300). The intervention was implemented by team coaches and consisted of information about risk factors for reinjury, rehabilitation principles, and a 10-step progressive rehabilitation program including return to play criteria. During the 2003 season, coaches reported individual exposure and all time loss injuries were evaluated by a doctor and a physiotherapist. Four teams (n = 100) withdrew from the study after randomization, leaving 10 teams with 241 players for analysis in both groups. There were 90 injured players (132 injuries) in the intervention group, and 10 of these (11%) suffered 14 reinjuries during the season. In the control group, 23 of 79 injured players (29%) had 40 recurrences (134 injuries). A Cox regression analysis showed a 66% reinjury risk reduction in the intervention group for all injury locations (hazard ratio [HR] 0.34, 95% confidence interval [CI] 0.16-0.72, P = .0047) and 75% for lower limb injuries (HR 0.25, 95% CI 0.11-0.57, P < .001). The preventive effect was greatest within the first week of return to play. Injured players in the intervention group complied with the intervention for 90 of 132 injuries (68%). The reinjury rate in amateur male soccer players was reduced after a controlled rehabilitation program implemented by coaches.

A Comparison of Athletic Movement Among Talent-Identified Juniors From Different Football Codes in Australia: Implications for Talent Development.

PubMed

Woods, Carl T; Keller, Brad S; McKeown, Ian; Robertson, Sam

2016-09-01

Woods, CT, Keller, BS, McKeown, I, and Robertson, S. A comparison of athletic movement among talent-identified juniors from different football codes in Australia: implications for talent development. J Strength Cond Res 30(9): 2440-2445, 2016-This study aimed to compare the athletic movement skill of talent-identified (TID) junior Australian Rules football (ARF) and soccer players. The athletic movement skill of 17 TID junior ARF players (17.5-18.3 years) was compared against 17 TID junior soccer players (17.9-18.7 years). Players in both groups were members of an elite junior talent development program within their respective football codes. All players performed an athletic movement assessment that included an overhead squat, double lunge, single-leg Romanian deadlift (both movements performed on right and left legs), a push-up, and a chin-up. Each movement was scored across 3 essential assessment criteria using a 3-point scale. The total score for each movement (maximum of 9) and the overall total score (maximum of 63) were used as the criterion variables for analysis. A multivariate analysis of variance tested the main effect of football code (2 levels) on the criterion variables, whereas a 1-way analysis of variance identified where differences occurred. A significant effect was noted, with the TID junior ARF players outscoring their soccer counterparts when performing the overhead squat and push-up. No other criterions significantly differed according to the main effect. Practitioners should be aware that specific sporting requirements may incur slight differences in athletic movement skill among TID juniors from different football codes. However, given the low athletic movement skill noted in both football codes, developmental coaches should address the underlying movement skill capabilities of juniors when prescribing physical training in both codes.

Neuromuscular and lower limb biomechanical differences exist between male and female elite adolescent soccer players during an unanticipated side-cut maneuver.

PubMed

Landry, Scott C; McKean, Kelly A; Hubley-Kozey, Cheryl L; Stanish, William D; Deluzio, Kevin J

2007-11-01

Female athletes are 2 to 8 times more likely than male athletes to injure the anterior cruciate ligament during a non-contact athletic maneuver. Identifying anterior cruciate ligament injury risk factors in female athletes may help with the development of preventive training programs aimed at reducing injury rates. Differences between genders in lower limb kinematics, kinetics, and neuromuscular patterns will be identified in an adolescent soccer population during an unanticipated side-cut maneuver. Controlled laboratory study. Forty-two elite adolescent soccer players (21 male and 21 female) performed an unanticipated side-cut maneuver, with the 3-dimensional kinematic, kinetic, and electromyographic lower limb data being analyzed using principal component analysis. The female athletes had higher gastrocnemius activity, normalized to maximal voluntary isometric contractions, and a mediolateral gastrocnemius activation imbalance that was not present in the male athletes during early stance to midstance of the side-cut. Female athletes demonstrated greater rectus femoris muscle activity throughout stance, and the only hamstring difference identified was a mediolateral activation imbalance in male athletes only. Female athletes performed the side-cut with less hip flexion and more hip external rotation and also generated a smaller hip flexion moment compared with the male athletes. This is the first study to identify gender-related differences in gastrocnemius muscle activity during an unanticipated cutting maneuver. The increased and imbalanced gastrocnemius muscle activity, combined with increased rectus femoris muscle activity and reduced hip flexion angles and moments in female subjects, may all have important contributing roles in the higher noncontact ACL injury rates observed in female athletes.

The Landing Error Scoring System as a Screening Tool for an Anterior Cruciate Ligament Injury–Prevention Program in Elite-Youth Soccer Athletes

PubMed Central

Padua, Darin A.; DiStefano, Lindsay J.; Beutler, Anthony I.; de la Motte, Sarah J.; DiStefano, Michael J.; Marshall, Steven W.

2015-01-01

Context Identifying neuromuscular screening factors for anterior cruciate ligament (ACL) injury is a critical step toward large-scale deployment of effective ACL injury-prevention programs. The Landing Error Scoring System (LESS) is a valid and reliable clinical assessment of jump-landing biomechanics. Objective To investigate the ability of the LESS to identify individuals at risk for ACL injury in an elite-youth soccer population. Design Cohort study. Setting Field-based functional movement screening performed at soccer practice facilities. Patients or Other Participants A total of 829 elite-youth soccer athletes (348 boys, 481 girls; age = 13.9 ± 1.8 years, age range = 11 to 18 years), of whom 25% (n = 207) were less than 13 years of age. Intervention(s) Baseline preseason testing for all participants consisted of a jump-landing task (3 trials). Participants were followed prospectively throughout their soccer seasons for diagnosis of ACL injuries (1217 athlete-seasons of follow-up). Main Outcome Measure(s) Landings were scored for “errors” in technique using the LESS. We used receiver operator characteristic curves to determine a cutpoint on the LESS. Sensitivity and specificity of the LESS in predicting ACL injury were assessed. Results Seven participants sustained ACL injuries during the follow-up period; the mechanism of injury was noncontact or indirect contact for all injuries. Uninjured participants had lower LESS scores (4.43 ± 1.71) than injured participants (6.24 ± 1.75; t1215 = −2.784, P = .005). The receiver operator characteristic curve analyses suggested that 5 was the optimal cutpoint for the LESS, generating a sensitivity of 86% and a specificity of 64%. Conclusions Despite sample-size limitations, the LESS showed potential as a screening tool to determine ACL injury risk in elite-youth soccer athletes. PMID:25811846

Maximal Sprinting Speed of Elite Soccer Players During Training and Matches.

PubMed

Djaoui, Leo; Chamari, Karim; Owen, Adam L; Dellal, Alexandre

2017-06-01

The aim of the present study was to compare (a) the maximal sprinting speed (MSS) attained by soccer players during matches (MSSmatch) according to their level of play (professional first French division vs. elite amateur fourth French division) and the playing positions and (b) the MSS attained by professional soccer players during 14 different types of small-sided games (SSG, MSSSSG) and match-play. All players monitored through the study performed a 40-m sprint test to assess individual MSS (MSStest) and compare it to the training and match activity, with the calculation of the percentage of MSStest (%MSStest) reached. No differences were found according to the level of play; however, positional wide players achieved a higher MSSmatch, %MSStest, and MSSSSG than central players (both defenders and midfielders) during matches and SSG. MSSmatch were higher than all MSSSSG, and MSSSSG were positively correlated with the area of the pitch (0.45, p < 0.001), its length (0.53, p < 0.001), and the number of players involved (0.38, p < 0.001). The closer SSG was to match situation in terms of rules, the higher the MSSSSG. Wide players reached higher MSS in match and SSG than central players, confirming the relevance of using SSG close to match situation to specifically prepare elite players to the maximal running speed demand of the match.

Validation and calibration of HeadCount, a self-report measure for quantifying heading exposure in soccer players.

PubMed

Catenaccio, E; Caccese, J; Wakschlag, N; Fleysher, R; Kim, N; Kim, M; Buckley, T A; Stewart, W F; Lipton, R B; Kaminski, T; Lipton, M L

2016-01-01

The long-term effects of repetitive head impacts due to heading are an area of increasing concern, and exposure must be accurately measured; however, the validity of self-report of cumulative soccer heading is not known. In order to validate HeadCount, a 2-week recall questionnaire, the number of player-reported headers was compared to the number of headers observed by trained raters for a men's and a women's collegiate soccer teams during an entire season of competitive play using Spearman's correlations and intraclass correlation coefficients (ICCs), and calibrated using a generalized estimating equation. The average Spearman's rho was 0.85 for men and 0.79 for women. The average ICC was 0.75 in men and 0.38 in women. The calibration analysis demonstrated that men tend to report heading accurately while women tend to overestimate. HeadCount is a valid instrument for tracking heading behaviour, but may have to be calibrated in women.

Single level anterior cervical discectomy and fusion for cervical disc herniation in a professional soccer player.

PubMed

Casagrande, Johnny; Zoia, Cesare; Clerici, Giulio; Uccella, Laura; Tabano, Antonio

2016-06-01

A 29-year old midfielder playing professional soccer complains of neck and right shoulder pain without apparent cause. A cervical MR shows disc herniation between C4 and C5 compressing 5th nerve root. The patient undergoes surgical discectomy plus interbody fusion with autologous bone and plate fixation with unicortical screws. No surgical complication is observed and after four weeks of rest, the patient begins a specific rehabilitation program including Tecar Therapy sessions and manual passive physical therapy for six weeks. Two times a week he attends hydrokinesis sessions. After eight weeks the athlete can restart working directly on soccer field and after less than four months he is back on an official competition.

An examination of the migratory transition of elite young European soccer players to the English Premier League.

PubMed

Richardson, David; Littlewood, Martin; Nesti, Mark; Benstead, Luke

2012-01-01

The migration of soccer players has increased in recent years. In this study, we examined the experiences of elite young soccer players as they engaged in a migratory transition from their home country to an English Premier League (EPL) club. Five young players, who made the migratory transition between the ages of 16 and 24, were interviewed. Data were analysed using the principles of content analysis. Verbatim text was then aligned to the emergent themes. Results indicate that young migratory players face the initial frenzy that is associated with an approach from an EPL club before going through a "decision" phase, followed by a period of "migration" and "acculturation" before establishing (or not) their "home from home". The challenges of leaving home and family while trying to establish themselves as a professional player in an environment that (still) appears to be beset with (traditional) English soccer culture (i.e. high tempo, ruthless, macho, and aggressive) are recounted. While the player's family was a significant source of social support, there is still a need for qualified personnel (e.g. sports psychologists) and/or appropriately trained international recruitment staff and football agents (i.e. in areas of social, psychological, and/or performance lifestyle) to support young players through their migratory transition.

Soft-assembled Multilevel Dynamics of Tactical Behaviors in Soccer

PubMed Central

Ric, Angel; Torrents, Carlota; Gonçalves, Bruno; Sampaio, Jaime; Hristovski, Robert

2016-01-01

This study aimed to identify the tactical patterns and the timescales of variables during a soccer match, allowing understanding the multilevel organization of tactical behaviors, and to determine the similarity of patterns performed by different groups of teammates during the first and second halves. Positional data from 20 professional male soccer players from the same team were collected using high frequency global positioning systems (5 Hz). Twenty-nine categories of tactical behaviors were determined from eight positioning-derived variables creating multivariate binary (Boolean) time-series matrices. Hierarchical principal component analysis (PCA) was used to identify the multilevel structure of tactical behaviors. The sequential reduction of each set level of principal components revealed a sole principal component as the slowest collective variable, forming the global basin of attraction of tactical patterns during each half of the match. In addition, the mean dwell time of each positioning-derived variable helped to understand the multilevel organization of collective tactical behavior during a soccer match. This approach warrants further investigations to analyze the influence of task constraints on the emergence of tactical behavior. Furthermore, PCA can help coaches to design representative training tasks according to those tactical patterns captured during match competitions and to compare them depending on situational variables. PMID:27761120

Expertise differences in anticipatory judgements during a temporally and spatially occluded task.

PubMed

Causer, Joe; Smeeton, Nicholas J; Williams, A Mark

2017-01-01

There is contradictory evidence surrounding the role of critical cues in the successful anticipation of penalty kicks in soccer. In the current study, skilled and less-skilled soccer goalkeepers were required to anticipate when viewing penalty kicks that were both spatially (full body; hip region) and temporally (-160 ms, -80 ms before, foot-ball contact) occluded. The skilled group outperformed the less-skilled group in all conditions. Participants performed better in the full body condition when compared to hip region condition. Performance in the hip only condition was significantly better than chance for the skilled group across all occlusion conditions. However, the less-skilled group were no better than chance in the hip condition for the early occlusion points when predicting direction and height. Later temporal occlusion conditions were associated with increased performance both in the correct response and correct direction analyses, but not for correct height. These data suggest that postural information solely from the hip region may be used by skilled goalkeepers to make accurate predictions of penalty kick direction, however, information from other sources are needed in order to make predictions of height. Findings demonstrate how the importance of anticipation cues evolve over time, which has implications for the design of training programs to enhance perceptual-cognitive skill.

Injury prevention in male youth soccer: Current practices and perceptions of practitioners working at elite English academies.

PubMed

Read, Paul J; Jimenez, Pablo; Oliver, Jon L; Lloyd, Rhodri S

2018-06-01

Forty-one practitioners inclusive of physiotherapists, sports scientists and strength and conditioning coaches from the academies of elite soccer clubs in the United Kingdom completed an on-line questionnaire which examined their: (1) background information; (2) perceptions of injury occurrence and risk factors; (3) screening and return to play; and (4) approach to designing and delivering injury prevention programmes with a response rate of 55% (41/75). Contact injuries were the most common mechanism reported and players between 13-16 years of age were perceived to be at the greatest risk. Pertinent risk factors included: reduced lower limb and eccentric hamstring strength, proprioception, muscle imbalances, and under developed foundational movement skills. Joint range of motion, jump tests, the functional movement screen, overhead and single leg squats were the most utilised screening methods. Training modalities rated in order of importance included: resistance training, flexibility development, agility, plyometrics and balance training. Training frequency was most commonly once or twice per week, during warm-ups, independent sessions or a combination of both. Injury prevention strategies in this cohort appear to be logical; however, the classification of injury occurrence and application of screening tools to identify "at risk" players do not align with existing research. The frequency and type of training used may also be insufficient to elicit an appropriate stimulus to address pertinent risk factors based on current recommendations.

Neuromuscular Coordination Deficit Persists 12 Months after ACL Reconstruction But Can Be Modulated by 6 Weeks of Kettlebell Training: A Case Study in Women's Elite Soccer

PubMed Central

Andersen, Christoffer H.; Bencke, Jesper; Ørntoft, Christina; Linnebjerg, Connie; Hölmich, Per

2017-01-01

The aim of the present single-case study was to investigate the effect of 6 weeks' kettlebell training on the neuromuscular risk profile for ACL injury in a high-risk athlete returning to sport after ACL reconstruction. A female elite soccer player (age 21 years) with no previous history of ACL injury went through neuromuscular screening as measured by EMG preactivity of vastus lateralis and semitendinosus during a standardized sidecutting maneuver. Subsequently, the player experienced a noncontact ACL injury. The player was screened again following postreconstruction rehabilitation, then underwent 6-week kettlebell training, and was subsequently screened again at 6-week follow-up. Prior to and after postreconstruction rehabilitation the player demonstrated a neuromuscular profile during sidecutting known to increase the risk for noncontact ACL injury, that is, reduced EMG preactivity for semitendinosus and elevated EMG preactivity for vastus lateralis. Subsequently, the 6-week kettlebell training increased semitendinosus muscle preactivity during sidecutting by 38 percentage points to a level equivalent to a neuromuscular low-risk profile. An ACL rehabilitated female athlete with a high-risk neuromuscular profile changed to low-risk in response to 6 weeks of kettlebell training. Thus, short-term kettlebell exercise with documented high levels of medial hamstring activation was found to transfer into high medial hamstring preactivation during a sidecutting maneuver. PMID:28197354

Modeling developmental changes in functional capacities and soccer-specific skills in male players aged 11-17 years.

PubMed

Valente-dos-Santos, João; Coelho-e-Silva, Manuel J; Simões, Filipe; Figueiredo, Antonio J; Leite, Neiva; Elferink-Gemser, Marije T; Malina, Robert M; Sherar, Lauren

2012-11-01

This study evaluates the contributions of age, growth, skeletal maturation, playing position and training to longitudinal changes in functional and skill performance in male youth soccer. Players were annually followed over 5 years (n = 83, 4.4 measurements per player). Composite scores for functional and skill domains were calculated to provide an overall estimate of performance. Players were also classified by maturity status and playing position at baseline. After testing for multicollinearity, two-level multilevel (longitudinal) regression models were obtained for functional and skill composite scores. The scores improved with age and training. Body mass was an additional predictor in both models [functional (late maturing): 13.48 + 1.05 × centered on chronological age (CA)-0.01 × centered CA(2)-0.19 × fat mass (FM) + 0.004 × annual volume training-1.04 × dribbling speed; skills (defenders): 7.62 + 0.62 × centered CA-0.06 × centered CA(2) + 0.04 × fat-free mass-0.03 x FM + 0.005 × annual volume training-0.19 × repeated-sprint ability + 0.02 × aerobic endurance]. Skeletal maturity status was a significant predictor of functional capacities and playing position of skill performance. Sound accuracy of each multilevel model was demonstrated on an independent cross-sectional sample (n = 52).

A concept mapping approach to identifying the barriers to implementing an evidence-based sports injury prevention programme.

PubMed

Donaldson, Alex; Callaghan, Aisling; Bizzini, Mario; Jowett, Andrew; Keyzer, Patrick; Nicholson, Matthew

2018-01-20

Understanding the barriers to programme use is important to facilitate implementation of injury prevention programmes in real-word settings. This study investigated the barriers to coaches of adolescent female soccer teams, in Victoria, Australia, implementing the evidence-based FIFA 11+ injury prevention programme. Concept mapping with data collected from 19 soccer coaches and administrators. Brainstorming generated 65 statements as barriers to 11+ implementation. After the statements were synthesised and edited, participants sorted 59 statements into groups (mean, 6.2 groups; range, 3-10 groups). Multidimensional scaling and hierarchical cluster analysis identified a six-cluster solution: Lack of 11+ knowledge among coaches (15 statements), Lack of player enjoyment and engagement (14), Lack of link to football-related goals (11), Lack of facilities and resources (8), Lack of leadership (6) and Lack of time at training (5). Statements in the 'Lack of 11+ knowledge among coaches' cluster received the highest mean importance (3.67 out of 5) and feasibility for the Football Federation to address (3.20) rating. Statements in the 'Lack of facilities and resources' cluster received the lowest mean importance rating (2.23), while statements in the 'Lack of time at training' cluster received the lowest mean feasibility rating (2.19). A multistrategy, ecological approach to implementing the 11+-with specific attention paid to improving coach knowledge about the 11+ and how to implement it, linking the 11+ to the primary goal of soccer training, and organisational leadership-is required to improve the uptake of the 11+ among the targeted coaches. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Evaluating SafeClub: can risk management training improve the safety activities of community soccer clubs?

PubMed

Abbott, K; Klarenaar, P; Donaldson, A; Sherker, S

2008-06-01

To evaluate a sports safety-focused risk-management training programme. Controlled before and after test. Four community soccer associations in Sydney, Australia. 76 clubs (32 intervention, 44 control) at baseline, and 67 clubs (27 intervention, 40 control) at post-season and 12-month follow-ups. SafeClub, a sports safety-focused risk-management training programme (3x2 hour sessions) based on adult-learning principles and injury-prevention concepts and models. Changes in mean policy, infrastructure and overall safety scores as measured using a modified version of the Sports Safety Audit Tool. There was no significant difference in the mean policy, infrastructure and overall safety scores of intervention and control clubs at baseline. Intervention clubs achieved higher post-season mean policy (11.9 intervention vs 7.5 controls), infrastructure (15.2 vs 10.3) and overall safety (27.0 vs 17.8) scores than did controls. These differences were greater at the 12-month follow-up: policy (16.4 vs 7.6); infrastructure (24.7 vs 10.7); and overall safety (41.1 vs 18.3). General linear modelling indicated that intervention clubs achieved statistically significantly higher policy (p<0.001), infrastructure (p<0.001) and overall safety (p<0.001) scores compared with control clubs at the post-season and 12-month follow-ups. There was also a significant linear interaction of time and group for all three scores: policy (p<0.001), infrastructure (p<0.001) and overall safety (p<0.001). SafeClub effectively assisted community soccer clubs to improve their sports safety activities, particularly the foundations and processes for good risk-management practice, in a sustainable way.

Effects of Sesame (Sesamum indicum L.) Supplementation on Creatine Kinase, Lactate Dehydrogenase, Oxidative Stress Markers, and Aerobic Capacity in Semi-Professional Soccer Players

PubMed Central

Barbosa, Carlos V. da Silva; Silva, Alexandre S.; de Oliveira, Caio V. C.; Massa, Nayara M. L.; de Sousa, Yasmim R. F.; da Costa, Whyara K. A.; Silva, Ayice C.; Delatorre, Plínio; Carvalho, Rhayane; Braga, Valdir de Andrade; Magnani, Marciane

2017-01-01

Nutritional intervention with antioxidants rich foods has been considered a strategy to minimize the effects of overtraining in athletes. This experimental, randomized, and placebo-controlled study evaluated the effects of consumption of sesame (Sesamum indicum L.) on muscle damage markers, oxidative stress, systemic inflammation, and aerobic performance in male semi-professional soccer players. Twenty athletes were randomly assigned to groups that received 40 g (two tablespoons) per day of sesame or a placebo during 28 days of regular training (exposed to routine training that includes loads of heavy training in the final half of the season). Before and after intervention, creatine kinase (CK), lactate dehydrogenase (LDH), malondialdehyde (MDA), superoxide dismutase (SOD), C-reactive protein (hs-CRP), and aerobic capacity were evaluated. Before intervention, a physiologic imbalance was noted in both groups related to CK and LDH levels. Sesame intake caused a reduction of CK (19%, p < 0.05), LDH (37%, p < 0.05), MDA (55%, p < 0.05) and hs-CRP (53%, p < 0.05) and increased SOD (14%, p < 0.05), vitamin A (25%, p < 0.05), and vitamin E (65%, p < 0.05) in the experimental group. These phenomena were accompanied by increased aerobic capacity (17%, p < 0.05). The placebo group showed an increase in CK (5%, p < 0.05) and no significant change in LDH, SOD or vitamin A. MDA levels decreased (21%, p < 0.05) and vitamin E increased (14%, p < 0.05) in the placebo group, but to a much lesser extent than in the experimental group. These results show that sesame consumption may reduce muscle damage and oxidative stress while improving the aerobic capacity in soccer players. PMID:28408889

Wellness, fatigue and physical performance acclimatisation to a 2-week soccer camp at 3600 m (ISA3600)

PubMed Central

Buchheit, Martin; Simpson, Ben M; Garvican-Lewis, Laura A; Hammond, Kristal; Kley, Marlen; Schmidt, Walter F; Aughey, Robert J; Soria, Rudy; Sargent, Charli; Roach, Gregory D; Claros, Jesus C Jimenez; Wachsmuth, Nadine; Gore, Christopher J; Bourdon, Pitre C

2013-01-01

Objectives To examine the time course of wellness, fatigue and performance during an altitude training camp (La Paz, 3600 m) in two groups of either sea-level (Australian) or altitude (Bolivian) native young soccer players. Methods Wellness and fatigue were assessed using questionnaires and resting heart rate (HR) and HR variability. Physical performance was assessed using HR responses to a submaximal run, a Yo-Yo Intermittent recovery test level 1 (Yo-YoIR1) and a 20 m sprint. Most measures were performed daily, with the exception of Yo-YoIR1 and 20 m sprints, which were performed near sea level and on days 3 and 10 at altitude. Results Compared with near sea level, Australians had moderate-to-large impairments in wellness and Yo-YoIR1 relative to the Bolivians on arrival at altitude. The acclimatisation of most measures to altitude was substantially slower in Australians than Bolivians, with only Bolivians reaching near sea-level baseline high-intensity running by the end of the camp. Both teams had moderately impaired 20 m sprinting at the end of the camp. Exercise HR had large associations (r>0.5–0.7) with changes in Yo-YoIR1 in both groups. Conclusions Despite partial physiological and perceptual acclimatisation, 2 weeks is insufficient for restoration of physical performance in young sea-level native soccer players. Because of the possible decrement in 20 m sprint time, a greater emphasis on speed training may be required during and after altitude training. The specific time course of restoration for each variable suggests that they measure different aspects of acclimatisation to 3600 m; they should therefore be used in combination to assess adaptation to altitude. PMID:24282195

Effects of Endurance Training Combined With Cognitive Remediation on Everyday Functioning, Symptoms, and Cognition in Multiepisode Schizophrenia Patients

PubMed Central

Malchow, Berend; Keller, Katriona; Hasan, Alkomiet; Dörfler, Sebastian; Schneider-Axmann, Thomas; Hillmer-Vogel, Ursula; Honer, William G.; Schulze, Thomas G.; Niklas, Andree; Wobrock, Thomas; Schmitt, Andrea; Falkai, Peter

2015-01-01

Aerobic exercise has been shown to improve symptoms in multiepisode schizophrenia, including cognitive impairments, but results are inconsistent. Therefore, we evaluated the effects of an enriched environment paradigm consisting of bicycle ergometer training and add-on computer-assisted cognitive remediation (CACR) training. To our knowledge, this is the first study to evaluate such an enriched environment paradigm in multiepisode schizophrenia. Twenty-two multiepisode schizophrenia patients and 22 age- and gender-matched healthy controls underwent 3 months of endurance training (30min, 3 times/wk); CACR training (30min, 2 times/wk) was added from week 6. Twenty-one additionally recruited schizophrenia patients played table soccer (known as “foosball” in the United States) over the same period and also received the same CACR training. At baseline and after 6 weeks and 3 months, we measured the Global Assessment of Functioning (GAF), Social Adjustment Scale-II (SAS-II), schizophrenia symptoms (Positive and Negative Syndrome Scale), and cognitive domains (Verbal Learning Memory Test [VLMT], Wisconsin Card Sorting Test [WCST], and Trail Making Test). After 3 months, we observed a significant improvement in GAF and in SAS-II social/leisure activities and household functioning adaptation in the endurance training augmented with cognitive remediation, but not in the table soccer augmented with cognitive remediation group. The severity of negative symptoms and performance in the VLMT and WCST improved significantly in the schizophrenia endurance training augmented with cognitive remediation group from week 6 to the end of the 3-month training period. Future studies should investigate longer intervention periods to show whether endurance training induces stable improvements in everyday functioning. PMID:25782770

Reducing muscle injuries and reinjuries in one italian professional male soccer team

PubMed Central

Melegati, Gianluca; Tornese, Davide; Gevi, Maurizio; Trabattoni, Alessandro; Pozzi, Grazia; Schonhuber, Herbert; Volpi, Piero

2013-01-01

Summary Background. The incidence rate of muscle injuries and re-injuries in professional elite soccer players actually is very high and may interfere with the fate of a championship. Purpose. To investigate the effect of a two-tiered injury prevention programme on first injury and re-injury incidence in top level male soccer players. Study design Case Series Study. Muscle injuries and re-injuries sustained by a group of 36 soccer player of an italian elite soccer team have been collected during 2010–2011 season. These data have been compared with those collected during the previous season in the same elite soccer team. Results. A total of 64 injuries occurred, 36 (56%) of which during practice and 28 (44%) during matches. Muscle injuries accounted for 31.3% of the total (n=20), 70% (n=14) of which occurred during practice and 30% (n=6) during matches. Hamstring were the muscles most often injured (n=11) In all, 3 re-injuries occurred (15% of muscle injuries). No early re-injuries occurred. The incidence was 2.5 injuries/1000 hours and the burden was 37 days absence/1000 hours. Conclusions. Through the implementation of a group and personalized injury prevention program, we were able to reduce the total number of muscle injuries and days absent because of injury, in a team of elite soccer players, as compared to the previous season. Specifically, muscle injuries accounted for 31% of all injuries, as compared to 59% of all injuries sustained by the team during the previous season. The number of injuries/1000 hours of exposure was reduced by half (from 5.6 to 2.5) and the days absent/1000 hours fell from 106 to 37. PMID:24596697

Relationships Between Internal and External Match-Load Indicators in Soccer Match Officials.

PubMed

Castillo, Daniel; Weston, Matthew; McLaren, Shaun J; Cámara, Jesús; Yanci, Javier

2017-08-01

The aims of this study were to describe the internal and external match loads (ML) of refereeing activity during official soccer matches and to investigate the relationship among the methods of ML quantification across a competitive season. A further aim was to examine the usefulness of differential perceived exertion (dRPE) as a tool for monitoring internal ML in soccer referees. Twenty field referees (FRs) and 43 assistant referees (ARs) participated in the study. Data were collected from 30 competitive matches (FR = 20 observations, AR = 43 observations) and included measures of internal (Edwards' heart-rate-derived training impulse [TRIMP EDW ]) ML, external (total distance covered, distance covered at high speeds, and player load) ML, and ML differentiated ratings of perceived respiratory (sRPE res ) and leg-muscle (sRPE mus ) exertion. Internal and external ML were all greater for FRs than for ARs (-19.7 to -72.5), with differences ranging from very likely very large to most likely extremely large. The relationships between internal-ML and external-ML indicators were, in most cases, unclear for FR (r < .35) and small to moderate for AR (r < .40). The authors found substantial differences between RPE res and RPE mus scores in both FRs (0.6 AU; ±90% confidence limits 0.4 AU) and ARs (0.4; ±0.3). These data demonstrate the multifaceted demands of soccer refereeing and thereby highlight the importance of monitoring both internal and external ML. Moreover, dRPE represents distinct dimensions of effort and may be useful in monitoring soccer referees' ML during official matches.

Physique and Body Composition in Soccer Players across Adolescence

PubMed Central

Nikolaidis, Pantelis Theodoros; Vassilios Karydis, Nikos

2011-01-01

Purpose Although the contribution of physique and body composition in soccer performance was recognized, these parameters of physical fitness were not well-studied in adolescent players. Aim of this study was to investigate physique and body composition across adolescence. Methods Male adolescents (N=297 aged 12.01–20.98 y), classified into nine one-year age-groups, child (control group, N=16 aged 7.34–11.97 y) and adult players (control group, N=29 aged 21.01–31.59 y), all members of competitive soccer clubs, performed a series of anthropometric measures (body mass, height, skinfolds, circumferences and girths), from which body mass index (BMI), percentage of body fat (BF%), fat mass (FM), fat free mass (FFM) and somatotype (Heath-Carter method) were calculated. Results Age had a positive association with FM (r=0.2, P<0.001) and FFM (r=0.68, P<0.001), and a negative association with BF (r=−0.12, P=0.047). Somatotype components changed across adolescence as well; age was linked to endomorphy (r=−0.17, P=0.005), mesomorphy (r=0.14, P=0.019) and ectomorphy (r=−0.17, P=0.004). Compared with age-matched general population, participants exhibited equal body mass, higher stature, lower body mass index and lower BF. Conclusion During adolescence, soccer players presented significant differences in terms of body composition and physique. Thus, these findings could be employed by coaches and fitness trainers engaged in soccer training in the context of physical fitness assessment and talent identification. PMID:22375222

Anthropometric and physiological predispositions for elite soccer.

PubMed

Reilly, T; Bangsbo, J; Franks, A

2000-09-01

This review is focused on anthropometric and physiological characteristics of soccer players with a view to establishing their roles within talent detection, identification and development programmes. Top-class soccer players have to adapt to the physical demands of the game, which are multifactorial. Players may not need to have an extraordinary capacity within any of the areas of physical performance but must possess a reasonably high level within all areas. This explains why there are marked individual differences in anthropometric and physiological characteristics among top players. Various measurements have been used to evaluate specific aspects of the physical performance of both youth and adult soccer players. The positional role of a player is related to his or her physiological capacity. Thus, midfield players and full-backs have the highest maximal oxygen intakes ( > 60 ml x kg(-1) x min(-1)) and perform best in intermittent exercise tests. On the other hand, midfield players tend to have the lowest muscle strength. Although these distinctions are evident in adult and elite youth players, their existence must be interpreted circumspectly in talent identification and development programmes. A range of relevant anthropometric and physiological factors can be considered which are subject to strong genetic influences (e.g. stature and maximal oxygen intake) or are largely environmentally determined and susceptible to training effects. Consequently, fitness profiling can generate a useful database against which talented groups may be compared. No single method allows for a representative assessment of a player's physical capabilities for soccer. We conclude that anthropometric and physiological criteria do have a role as part of a holistic monitoring of talented young players.

The upper values of plasma creatine kinase of professional soccer players during the Brazilian National Championship.

PubMed

Lazarim, Fernanda L; Antunes-Neto, Joaquim M F; da Silva, Fernando O C; Nunes, Lázaro A S; Bassini-Cameron, Adriana; Cameron, Luiz-Cláudio; Alves, Armindo A; Brenzikofer, René; de Macedo, Denise Vaz

2009-01-01

The current schedule of the Brazilian Soccer Championship may not give players enough recovery time between games. This could increase the chances of muscle damage and impaired performance. We hypothesized that plasma creatine kinase (CK) activity could be a reliable indirect marker of muscle overload in soccer players, so we sought to identify the reference values for upper limits of CK activity during a real-life elite competition. This study analyzed changes in plasma CK activity in 128 professional soccer players at different times during the Brazilian Championship. The upper limits of the 97.5th and 90th percentiles determined for CK activity were 1.338U/L and 975U/L, respectively, markedly higher than values previously reported in the literature. We also evaluated a team monthly throughout the Championship. The upper limit of the 90th percentile, 975U/L, was taken as the decision limit. Six players showing plasma CK values higher than this were asked to decrease their training for 1 week. These players presented lower CK values afterwards. Only one player with a CK value higher than the decision limit (1800U/L 1 day before a game) played on the field and was unfortunately injured during the game. The CK activity in all the other players showed a significant decrease over the course of the Championship, and the values became more homogeneous at the end. The results presented here suggest that plasma CK upper limit values can be used as a practical alternative for early detection of muscle overload in competing soccer players.

Hip Strength as an Intrinsic Risk Factor for Lateral Ankle Sprains in Youth Soccer Players: A 3-Season Prospective Study.

PubMed

De Ridder, Roel; Witvrouw, Erik; Dolphens, Mieke; Roosen, Philip; Van Ginckel, Ans

2017-02-01

Numerous epidemiological studies have emphasized the burden of lateral ankle sprains in youth soccer players. However, no prospective study has identified intrinsic physical and modifiable risk factors for these injuries in this particular population. Although injury prevention programs in soccer incorporate proximal hip and core stability exercises, it is striking that the relationship between impaired proximal hip function and ankle sprains has not yet been prospectively investigated in youth soccer players. This prospective study aimed to examine whether hip muscle strength is a risk factor for sustaining a lateral ankle sprain in youth soccer players. We hypothesized that decreased hip muscle strength would predispose youth soccer players to an increased risk of lateral ankle sprains. Case-control study; Level of evidence, 3. This study included a total of 133 male youth soccer players (age divisions U11-U17) for analysis. At the beginning of the season, anthropometric characteristics were collected and hip muscle strength was assessed using a handheld dynamometer. Injury registration was performed by the team medical staff during 3 consecutive seasons. A principal-component, multivariate Cox regression analysis was performed to identify potential risk factors for sustaining a lateral ankle sprain. Twelve participants (18% of all reported injuries) sustained a lateral ankle sprain (0.36 per 1000 athletic-exposure hours). After adjustment for body size dependencies and other hip muscle forces, an increase in hip muscle extension force was associated with a significant decrease in the hazard of the injury (hazard ratio, 0.3; 95% confidence interval, 0.1-0.9; P = .028). No other study variable could be identified as a risk factor for lateral ankle sprains. Reduced hip extension muscle strength is an independent risk factor for lateral ankle sprains in male youth soccer players. Other hip muscle strength outcomes were not identified as risk factors. Replication in larger samples with more injured cases is warranted to further ascertain the importance of this risk factor.

Player Load, Acceleration, and Deceleration During Forty-Five Competitive Matches of Elite Soccer.

PubMed

Dalen, Terje; Ingebrigtsen, Jørgen; Ettema, Gertjan; Hjelde, Geir Havard; Wisløff, Ulrik

2016-02-01

The use of time-motion analysis has advanced our understanding of position-specific work rate profiles and the physical requirements of soccer players. Still, many of the typical soccer activities can be neglected, as these systems only examine activities measured by distance and speed variables. This study used triaxial accelerometer and time-motion analysis to obtain new knowledge about elite soccer players' match load. Furthermore, we determined acceleration/deceleration profiles of elite soccer players and their contribution to the players' match load. The data set includes every domestic home game (n = 45) covering 3 full seasons (2009, 2010, and 2011) for the participating team (Rosenborg FC), and includes 8 central defenders (n = 68), 9 fullbacks (n = 83), 9 central midfielders (n = 70), 7 wide midfielders (n = 39), and 5 attackers (A, n = 50). A novel finding was that accelerations contributed to 7-10% of the total player load for all player positions, whereas decelerations contributed to 5-7%. Furthermore, the results indicate that other activities besides the high-intensity movements contribute significantly to the players' total match workload. Therefore, motion analysis alone may underestimate player load because many high-intensity actions are without a change in location at the pitch or they are classified as low-speed activity according to current standards. This new knowledge may help coaches to better understand the different ways players achieve match load and could be used in developing individualized programs that better meet the "positional physical demands" in elite soccer.

A meta-analysis of the effect of neuromuscular training on the prevention of the anterior cruciate ligament injury in female athletes.

PubMed

Yoo, Jae Ho; Lim, Bee Oh; Ha, Mina; Lee, Soo Won; Oh, Soo Jin; Lee, Yong Seuk; Kim, Jin Goo

2010-06-01

Female athletes are more prone to anterior cruciate ligament (ACL) injury than their male counterparts, presumably because of anatomical, hormonal, and neuromuscular differences. Of these three, only the neuromuscular component can be modified by preventive exercise. We aimed to evaluate the effect of a neuromuscular protocol on the prevention of ACL injury by performing meta-analysis, and to identify essential factors by subgroup analysis. An extensive literature review was conducted to identify relevant studies, and eventually, only seven randomized controlled trials or prospective cohort studies were included in the analysis. The odds ratios (OR) and the confidence interval (CI) for the overall effects of training and of potentially contributory factors were estimated. The OR and the 95% CI for the overall effect of the preventive training were 0.40 and [0.27, 0.60], respectively. Subgroup analysis revealed that an age under 18, soccer rather than handball, pre- and in-season training rather than either pre- or in-season training, and the plyometrics and strengthening components rather than balancing were significant. Meta-analysis showed that pre- and in-season neuromuscular training with an emphasis on plyometrics and strengthening exercises was effective at preventing ACL injury in female athletes, especially in those under 18 years of age. Further study is required to develop a relevant training program protocol of appropriate intensity.

Real-time optimized biofeedback utilizing sport techniques (ROBUST): a study protocol for a randomized controlled trial.

PubMed

Taylor, Jeffrey B; Nguyen, Anh-Dung; Paterno, Mark V; Huang, Bin; Ford, Kevin R

2017-02-07

Anterior cruciate ligament (ACL) injuries in female athletes lead to a variety of short- and long-term physical, financial, and psychosocial ramifications. While dedicated injury prevention training programs have shown promise, ACL injury rates remain high as implementation has not become widespread. Conventional prevention programs use a combination of resistance, plyometric, balance and agility training to improve high-risk biomechanics and reduce the risk of injury. While many of these programs focus on reducing knee abduction load and posture during dynamic activity, targeting hip extensor strength and utilization may be more efficacious, as it is theorized to be an underlying mechanism of injury in adolescent female athletes. Biofeedback training may complement traditional preventive training, but has not been widely studied in connection with ACL injuries. We hypothesize that biofeedback may be needed to maximize the effectiveness of neuromuscular prophylactic interventions, and that hip-focused biofeedback will improve lower extremity biomechanics to a larger extent than knee-focused biofeedback during dynamic sport-specific tasks and long-term movement strategies. This is an assessor-blind, randomized control trial of 150 adolescent competitive female (9-19 years) soccer players. Each participant receives 3x/week neuromuscular preventive training and 1x/week biofeedback, the mode depending on their randomization to one of 3 biofeedback groups (hip-focused, knee-focused, sham). The primary aim is to assess the impact of biofeedback training on knee abduction moments (the primary biomechanical predictor of future ACL injury) during double-leg landings, single-leg landings, and unplanned cutting. Testing will occur immediately before the training intervention, immediately after the training intervention, and 6 months after the training intervention to assess the long-term retention of modified biomechanics. Secondary aims will assess performance changes, including hip and core strength, power, and agility, and the extent to which maturation effects biofeedback efficacy. The results of the Real-time Optimized Biofeedback Utilizing Sport Techniques (ROBUST) trial will help complement current preventive training and may lead to clinician-friendly methods of biofeedback to incorporate into widespread training practices. Date of publication in ClinicalTrials.gov: 20/04/2016. ClinicalTrials.gov Identifier: NCT02754700 .

CyberHunt.

ERIC Educational Resources Information Center

Truby, Dana

2001-01-01

Using a soccer cyberhunt, elementary school students can learn all about the game of soccer while practicing computer skills. The cyberhunt teaches about: the history of soccer; soccer's name in other countries; number of players on the field; women's World Cup soccer; soccer rules; soccer legend, Pele; soccer moves; and the soccer ball. A…

Skeletal Maturation and Aerobic Performance in Young Soccer Players from Professional Academies.

PubMed

Teixeira, A S; Valente-dos-Santos, J; Coelho-E-Silva, M J; Malina, R M; Fernandes-da-Silva, J; Cesar do Nascimento Salvador, P; De Lucas, R D; Wayhs, M C; Guglielmo, L G A

2015-11-01

The contribution of chronological age, skeletal age (Fels method) and body size to variance in peak velocity derived from the Carminatti Test was examined in 3 competitive age groups of Brazilian male soccer players: 10-11 years (U-12, n=15), 12-13 years (U-14, n=54) and 14-15 years (U-16, n=23). Body size and soccer-specific aerobic fitness were measured. Body composition was predicted from skinfolds. Analysis of variance and covariance (controlling for chronological age) were used to compare soccer players by age group and by skeletal maturity status within of each age group, respectively. Relative skeletal age (skeletal age minus chronological age), body size, estimated fat-free mass and performance on the Carminatti Test increased significantly with age. Carminatti Test performance did not differ among players of contrasting skeletal maturity status in the 3 age groups. Results of multiple linear regressions indicated fat mass (negative) and chronological age (positive) were significant predictors of peak velocity derived from the Carminatti Test, whereas skeletal age was not a significant predictor. In conclusion, the Carminatti Test appears to be a potentially interesting field protocol to assess intermittent endurance running capacity in youth soccer programs since it is independent of biological maturity status. © Georg Thieme Verlag KG Stuttgart · New York.

Science and football: a review of applied research in the football codes.

PubMed

Reilly, Thomas; Gilbourne, David

2003-09-01

Over the last two decades there has been a growth in research directly related to football. Although most of this research is focused on soccer (association football), there has been a steady increase in publications related to the other football codes. There is evidence of more systematic training and selection influencing the anthropometric profiles of players who compete at the highest level. Fitness is being optimized to cope with match demands while accommodating the need for specific requirements of positional roles. There is evidence of work rate being higher in contemporary football games than in previous decades, with consequences for training and dietary practices. Notation analysis of actions during matches is now used regularly to provide detailed objective feedback on performance to players and coaches. Training regimens are designed for game-specific purposes where possible. Sports psychologists working in a football context have a more eclectic body of knowledge to draw from. In the professional soccer clubs, the rewards associated with a successful investment in youth academies have helped to focus attention on talent identification and development models. It is a challenge to those specializing in science and football to contribute to the success of such schemes.

The acute:chonic workload ratio in relation to injury risk in professional soccer.

PubMed

Malone, Shane; Owen, Adam; Newton, Matt; Mendes, Bruno; Collins, Kieran D; Gabbett, Tim J

2017-06-01

To examine the association between combined sRPE measures and injury risk in elite professional soccer. Observational cohort study. Forty-eight professional soccer players (mean±SD age of 25.3±3.1 yr) from two elite European teams were involved within a one season study. Players completed a test of intermittent-aerobic capacity (Yo-YoIR1) to assess player's injury risk in relation to intermittent aerobic capacity. Weekly workload measures and time loss injuries were recorded during the entire period. Rolling weekly sums and week-to-week changes in workload were measured, allowing for the calculation of the acute:chronic workload ratio, which was calculated by dividing the acute (1-weekly) and chronic (4-weekly) workloads. All derived workload measures were modelled against injury data using logistic regression. Odds ratios (OR) were reported against a reference group. Players who exerted pre-season 1-weekly loads of ≥1500 to ≤2120AU were at significantly higher risk of injury compared to the reference group of ≤1500AU (OR=1.95, p=0.006). Players with increased intermittent-aerobic capacity were better able to tolerate increased 1-weekly absolute changes in training load than players with lower fitness levels (OR=4.52, p=0.011). Players who exerted in-season acute:chronic workload ratios of >1.00 to <1.25 (OR=0.68, p=0.006) were at significantly lower risk of injury compared to the reference group (≤0.85). These findings demonstrate that an acute:chronic workload of between 1.00 and 1.25 is protective for professional soccer players. A higher intermittent-aerobic capacity appears to offer greater injury protection when players are exposed to rapid changes in workload in elite soccer players. Moderate workloads, coupled with moderate-low to moderate-high acute:chronic workload ratios, appear to be protective for professional soccer players. Copyright © 2016 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

The within-match patterns of locomotor efficiency during professional soccer match play: Implications for injury risk?

PubMed

Barrett, Steve; Midgley, Adrian; Reeves, Matt; Joel, Tom; Franklin, Ed; Heyworth, Rob; Garrett, Andrew; Lovell, Ric

2016-10-01

The principle aim of the current study was to examine within-match patterns of locomotor efficiency in professional soccer, determined as the ratio between tri-axial accelerometer data (PlayerLoad™) and locomotor activities. Between match variability and determinants of PlayerLoad™ during match play were also assessed. A single cohort, observational study. Tri-axial accelerometer data (PlayerLoad™) was recorded during 86 competitive soccer matches in 63 English championship players (574 match observations). Accelerometer data accumulated (PlayerLoad Vector Magnitude [PLVM]) from the individual-component planes of PlayerLoad™ (anterior-posterior PlayerLoad™ [PLAP], medial-lateral PlayerLoad™ [PLML] and vertical PlayerLoad™ [PLV]), together with locomotor activity (Total Distance Covered [TDC]) were determined in 15-min segments. Locomotor efficiency was calculated using the ratio of PLVM and TDC (PlayerLoad™ per metre). The proportion of variance explaining the within-match trends in PLVM, PLAP, APML, APv, and TDC was determined owing to matches, individual players, and positional role. PLVM, PLAP, APML, APv and TDC reduced after the initial 15-min match period (p=0.001; η(2)=0.22-0.43, large effects). PL:TDC increased in the last 15min of each half (p=0.001; η(2)=0.25, large effect). The variance in PLVM during soccer match-play was explained by individual players (63.9%; p=0.001) and between-match variation (21.6%; p=0.001), but not positional role (14.1%; p=0.364). Locomotor efficiency is lower during the latter stages of each half of competitive soccer match-play, a trend synonymous with observations of increased injury incidence and fatigue in these periods. Locomotor efficiency may be a valuable metric to identify fatigue and heightened injury risk during soccer training and match-play. Copyright © 2015 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Soccer-Specific Fatigue and Eccentric Hamstrings Muscle Strength

PubMed Central

Greig, Matt; Siegler, Jason C

2009-01-01

Context: Epidemiologic findings of higher incidences of hamstrings muscle strains during the latter stages of soccer match play have been attributed to fatigue. Objective: To investigate the influence of soccer-specific fatigue on the peak eccentric torque of the knee flexor muscles. Design: Descriptive laboratory study. Setting: Controlled laboratory environment. Patients or Other Participants: Ten male professional soccer players (age  =  24.7 ± 4.4 years, mass  =  77.1 ± 8.3 kg, V̇o2max  =  63.0 ± 4.8 mL·kg−1·min−1). Intervention(s): Participants completed an intermittent treadmill protocol replicating the activity profile of soccer match play, with a passive halftime interval. Before exercise and at 15-minute intervals, each player completed isokinetic dynamometer trials. Main Outcome Measure(s): Peak eccentric knee flexor torque was quantified at isokinetic speeds of 180° · s−1, 300° · s−1, and 60° · s−1, with 5 repetitions at each speed. Results: Peak eccentric knee flexor torque at the end of the game (T300eccH105  =  127 ± 25 Nm) and at the end of the passive halftime interval (T300eccH60  =  133 ± 32 Nm) was reduced relative to T300eccH00 (167 ± 35 Nm, P < .01) and T300eccH15 (161 ± 35 Nm, P  =  .02). Conclusions: Eccentric hamstrings strength decreased as a function of time and after the halftime interval. This finding indicates a greater risk of injuries at these specific times, especially for explosive movements, in accordance with epidemiologic observations. Incorporating eccentric knee flexor exercises into resistance training sessions that follow soccer-specific conditioning is warranted to try to reduce the incidence or recurrence of hamstrings strains. PMID:19295963

Computer-based coding of free-text job descriptions to efficiently identify occupations in epidemiological studies.

PubMed

Russ, Daniel E; Ho, Kwan-Yuet; Colt, Joanne S; Armenti, Karla R; Baris, Dalsu; Chow, Wong-Ho; Davis, Faith; Johnson, Alison; Purdue, Mark P; Karagas, Margaret R; Schwartz, Kendra; Schwenn, Molly; Silverman, Debra T; Johnson, Calvin A; Friesen, Melissa C

2016-06-01

Mapping job titles to standardised occupation classification (SOC) codes is an important step in identifying occupational risk factors in epidemiological studies. Because manual coding is time-consuming and has moderate reliability, we developed an algorithm called SOCcer (Standardized Occupation Coding for Computer-assisted Epidemiologic Research) to assign SOC-2010 codes based on free-text job description components. Job title and task-based classifiers were developed by comparing job descriptions to multiple sources linking job and task descriptions to SOC codes. An industry-based classifier was developed based on the SOC prevalence within an industry. These classifiers were used in a logistic model trained using 14 983 jobs with expert-assigned SOC codes to obtain empirical weights for an algorithm that scored each SOC/job description. We assigned the highest scoring SOC code to each job. SOCcer was validated in 2 occupational data sources by comparing SOC codes obtained from SOCcer to expert assigned SOC codes and lead exposure estimates obtained by linking SOC codes to a job-exposure matrix. For 11 991 case-control study jobs, SOCcer-assigned codes agreed with 44.5% and 76.3% of manually assigned codes at the 6-digit and 2-digit level, respectively. Agreement increased with the score, providing a mechanism to identify assignments needing review. Good agreement was observed between lead estimates based on SOCcer and manual SOC assignments (κ 0.6-0.8). Poorer performance was observed for inspection job descriptions, which included abbreviations and worksite-specific terminology. Although some manual coding will remain necessary, using SOCcer may improve the efficiency of incorporating occupation into large-scale epidemiological studies. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

A review of football injuries on third and fourth generation artificial turfs compared with natural turf.

PubMed

Williams, Sean; Hume, Patria A; Kara, Stephen

2011-11-01

Football codes (rugby union, soccer, American football) train and play matches on natural and artificial turfs. A review of injuries on different turfs was needed to inform practitioners and sporting bodies on turf-related injury mechanisms and risk factors. Therefore, the aim of this review was to compare the incidence, nature and mechanisms of injuries sustained on newer generation artificial turfs and natural turfs. Electronic databases were searched using the keywords 'artificial turf', 'natural turf', 'grass' and 'inj*'. Delimitation of 120 articles sourced to those addressing injuries in football codes and those using third and fourth generation artificial turfs or natural turfs resulted in 11 experimental papers. These 11 papers provided 20 cohorts that could be assessed using magnitude-based inferences for injury incidence rate ratio calculations pertaining to differences between surfaces. Analysis showed that 16 of the 20 cohorts showed trivial effects for overall incidence rate ratios between surfaces. There was increased risk of ankle injury playing on artificial turf in eight cohorts, with incidence rate ratios from 0.7 to 5.2. Evidence concerning risk of knee injuries on the two surfaces was inconsistent, with incidence rate ratios from 0.4 to 2.8. Two cohorts showed beneficial inferences over the 90% likelihood value for effects of artificial surface on muscle injuries for soccer players; however, there were also two harmful, four unclear and five trivial inferences across the three football codes. Inferences relating to injury severity were inconsistent, with the exception that artificial turf was very likely to have harmful effects for minor injuries in rugby union training and severe injuries in young female soccer players. No clear differences between surfaces were evident in relation to training versus match injuries. Potential mechanisms for differing injury patterns on artificial turf compared with natural turf include increased peak torque and rotational stiffness properties of shoe-surface interfaces, decreased impact attenuation properties of surfaces, differing foot loading patterns and detrimental physiological responses. Changing between surfaces may be a precursor for injury in soccer. In conclusion, studies have provided strong evidence for comparable rates of injury between new generation artificial turfs and natural turfs. An exception is the likely increased risk of ankle injury on third and fourth generation artificial turfs. Therefore, ankle injury prevention strategies must be a priority for athletes who play on artificial turf regularly. Clarification of effects of artificial surfaces on muscle and knee injuries are required given inconsistencies in incidence rate ratios depending on the football code, athlete, gender or match versus training.

The Importance of Postural Control in Relation to Technical Abilities in Small-Sided Soccer Games

PubMed Central

Edis, Çağlar; Vurgun, Hikmet

2016-01-01

Abstract Making assessments regarding postural control and balance is very important for injury prevention in soccer. However, there has been no study that has associated postural control variables with branch-specific technical properties in a game. The aim of the present study was to determine the relationships between variables designating postural control levels and technical performance variables in different (1:1, 2:2 and 3:3) small-sided games (SSGs). Sixteen trained male amateur soccer players volunteered to take part in the study (age 17.2 ± 1.02 years, body height 176.25 ± 0.07 m, body mass 67.67 ± 13.27 kg). Following familiarization sessions, postural control was evaluated using one-leg and both-leg quiet-stance positions by measuring postural sway with a Tekscan HR Mat™ in anterior–posterior and medial–lateral directions. Later, 1:1, 2:2 and 3:3 SSGs were performed at two-day intervals and the technical variables specified for each game were analyzed. A Spearman’s rank-order correlation analysis demonstrated the relationship between postural control and soccer-specific technical variables in 1:1 (r-values ranging from 0.582 to 0.776), 2:2 (rvalues ranging from 0.511 to 0.740) and 3:3 (r-values ranging from 0.502 to 0.834) SSGs. In addition, a Wilcoxon signed rank test revealed differences between SSGs in terms of several variables. The results of the study showed that higher postural control levels are among the important variables that affect success in the performance of technical skills under rival pressure and suddenly changing conditions. Therefore, it is recommended that in addition to its use for injury prevention purposes, balance training should be conducted to improve branch-specific technical skills and to increase the levels of their successful performance in a game. PMID:28149410

The Importance of Postural Control in Relation to Technical Abilities in Small-Sided Soccer Games.

PubMed

Edis, Çağlar; Vural, Faik; Vurgun, Hikmet

2016-12-01

Making assessments regarding postural control and balance is very important for injury prevention in soccer. However, there has been no study that has associated postural control variables with branch-specific technical properties in a game. The aim of the present study was to determine the relationships between variables designating postural control levels and technical performance variables in different (1:1, 2:2 and 3:3) small-sided games (SSGs). Sixteen trained male amateur soccer players volunteered to take part in the study (age 17.2 ± 1.02 years, body height 176.25 ± 0.07 m, body mass 67.67 ± 13.27 kg). Following familiarization sessions, postural control was evaluated using one-leg and both-leg quiet-stance positions by measuring postural sway with a Tekscan HR Mat™ in anterior-posterior and medial-lateral directions. Later, 1:1, 2:2 and 3:3 SSGs were performed at two-day intervals and the technical variables specified for each game were analyzed. A Spearman's rank-order correlation analysis demonstrated the relationship between postural control and soccer-specific technical variables in 1:1 (r-values ranging from 0.582 to 0.776), 2:2 (rvalues ranging from 0.511 to 0.740) and 3:3 (r-values ranging from 0.502 to 0.834) SSGs. In addition, a Wilcoxon signed rank test revealed differences between SSGs in terms of several variables. The results of the study showed that higher postural control levels are among the important variables that affect success in the performance of technical skills under rival pressure and suddenly changing conditions. Therefore, it is recommended that in addition to its use for injury prevention purposes, balance training should be conducted to improve branch-specific technical skills and to increase the levels of their successful performance in a game.

Relationship Between Internal Load Indicators and Changes on Intermittent Performance After the Preseason in Professional Soccer Players.

PubMed

Campos-Vazquez, Miguel A; Toscano-Bendala, Francisco J; Mora-Ferrera, José C; Suarez-Arrones, Luis J

2017-06-01

The aim of this study was to examine the effects of accumulated internal training load (ITL) during the preseason (4 weeks) on changes in the intermittent performance, in a professional soccer team. Twelve professionals soccer players (Mean ± SD age: 27.7 ± 4.3 years; height: 177.1 ± 6.2 cm; body mass: 73.1 ± 5.2 kg; % body fat [Faulkner]: 10.2 ± 1.2) belonging to a Spanish second division team (2013-2014) participated in this study. The 30-15 intermittent fitness test was performed before and after the preseason, and the speed for the last period completed by each player was recorded (VIFT). During the preseason, the team alternated practice of training sessions (TRNs) with friendly matches (FMs). Session rating of perceived exertion (sRPE), heart rate (HR), and HR reserve were analyzed every TRN and FM to calculate ITL (ITL: sRPE-TL, Edward's-TL and Edward's-TLres). The players' VIFT substantially increased after the preseason period (20.1 ± 0.8 vs. 21.1 ± 0.8 km·h; effect size [ES] = 1.15 ± 0.25; almost certainly). The average value of sRPE throughout FMs was substantially greater than the value of the TRNs (7.4 ± 0.9 vs. 5.25 ± 0.2; ES = 2.31 ± 2.45; almost certainly). sRPE-TL, practice volume, and sum of RPE during the preseason were positively and largely correlated (r = 0.70-0.75) with changes on intermittent performance. No relationships were found between HR-derived measures of exercise load and changes on intermittent fitness. The present results suggest that practice volume and subjective measures of TL, related better than HR-based TL methods to changes on intermittent performance after the preseason, in professional soccer players.

Match-derived relative pitch area changes the physical and team tactical performance of elite soccer players in small-sided soccer games.

PubMed

Olthof, Sigrid B H; Frencken, Wouter G P; Lemmink, Koen A P M

2018-07-01

Small-sided games (SSGs) are used in training sessions to prepare for full-sized matches. For the same number of players, smaller pitch sizes result in decreased physical performance and shorter interpersonal distances. A relative pitch area derived from the full-sized match results in larger pitch sizes and this may increase the fit between SSGs and full-sized matches. This study aimed to investigate SSGs with a traditional small pitch and a match-derived relative pitch area in youth elite soccer players. Four age categories (under-13, under-15, under-17 and under-19) played 4 vs. 4 plus goalkeepers on a small (40x30m, 120m 2 relative pitch area) and large pitch (68x47m, 320m 2 relative pitch area). The number of games per age category ranged 15-30. Positional data (LPM-system) were collected to determine physical (total distance covered, high intensity distance and number of sprints) and team tactical (inter-team distance, LPW-ratio, surface area, stretch indices, goalkeeper-defender distance) performance measures and tactical variability. On a large pitch, physical performance significantly increased, inter-team and intra-team distances were significantly larger and tactical variability of intra-team distance measures significantly increased. The match-derived relative pitch area is an important training manipulation and leads to changes in physical and tactical performance 4 vs. 4 plus goalkeepers.