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.

Somatotype and stress hormone levels in young soccer players.

PubMed

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

2015-11-01

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.

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

Dynamic balance ability in young elite soccer players: implication of isometric strength.

PubMed

Chtara, Moktar; Rouissi, Mehdi; Bragazzi, Nicola L; Owen, Adam L; Haddad, Monoem; Chamari, Karim

2018-04-01

Soccer requires maintaining unilateral balance when executing movement with the contralateral leg. Despite the fact that balance requires standing with maintaining isometric posture with the support leg, currently there is a lack of studies regarding the implication of isometric strength on dynamic balance's performance among young soccer players. Therefore, the aim of this study was to examine the relationship between the Y-Balance Test and 12 lower limbs isometric strength tests. Twenty-six right footed soccer players (mean±SD, age=16.2±1.6 years, height=175±4.2 cm, body mass=68.8±6.1 kg) performed a dynamic balance test (star excursion balance-test with dominant- (DL) and nondominant-legs (NDL). Furthermore, maximal isometric contraction tests of 12 lower limb muscle groups were assessed in DL and NDL. Correlations analysis reported a significant positive relationship between some of isometric strength tests (with DL and NDL) and the Y-Balance Test. Furthermore, stepwise multiple regression analysis showed that maximal isometric strength explained between 21.9% and 49.4% of the variance of the Y-Balance Test. Moreover, maximal isometric strength was dependent upon the reaching angle of the Y-Balance Test and the leg used to support body weight. This study showed a significant implication of maximal isometric strength of the lower limb and the Y-Balance Test. Moreover, the present investigation suggests the implementation of specific lower limb strengthening exercises depending on players' deficit in each reaching direction and leg. This result suggests that further studies should experiment if increasing lower limbs isometric strength could improve dynamic balance ability among young soccer players.

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

Effects of intermittent-endurance fitness on match performance in young male soccer players.

PubMed

Castagna, Carlo; Impellizzeri, Franco; Cecchini, Emilio; Rampinini, Ermanno; Alvarez, José Carlos Barbero

2009-10-01

The purpose of this study was to examine the effect of specific endurance (Yo-Yo Intermittent recovery test level 1, Yo-Yo IR1) on match performance in male youth soccer. Twenty-one young, male soccer players (age 14.1 +/- 0.2 years) were involved in the study. Players were observed during international championship games of corresponding age categories and completed the Yo-Yo IR1 on a separate occasion. Physical (distance coverage) and physiological match demands were assessed using Global Positioning System technology and heart rate (HR) short-range telemetry, respectively. During the match (two 30-minutes halves), players covered 6,204 +/- 731 m, of which 985 +/- 362 m (16%) were performed at high intensities (speed >13 kmxh, HIA). A significant decrement (3.8%, p = 0.003) in match coverage was evident during the second half. No significant (p = 0.07) difference between halves was observed for HIA (p = 0.56) and sprint (speed >18 kmxh, SPR) distances. During the first and second halves, players attained the 86 +/- 5.5 and 85 +/- 6.0% of HRmax (p = 0.17), respectively. Peak HR during the first and second halves were 100 +/- 4 and 99.4 +/- 4.7% of HRmax, respectively. Yo-Yo IR1 performance (842 +/- 352 m) was significantly related to match HIA (r = 0.77, p < 0.001) and total distance (r = 0.65, p = 0.002). This study's results showed that specific endurance, as determined by Yo-Yo IR1 performance, positively affects physical match performance in male young soccer players. Consequently, the Yo-Yo IR1 test may be regarded as a valid test to assess game readiness and guide training prescription in male youth soccer players.

Effects of small-sided games on physical conditioning and performance in young soccer players.

PubMed

Katis, Athanasios; Kellis, Eleftherios

2009-01-01

The purpose of this study was to examine, first, the movement actions performed during two different small-sided games and, second, their effects on a series of field endurance and technical tests. Thirty-four young soccer players (age: 13 ± 0.9 yrs; body mass: 62.3 ± 15.1 kg; height: 1.65 ± 0.06 m) participated in the study. Small-sided games included three-a-side (3 versus 3 players) and six-a-side (6 versus 6 players) games consisting of 10 bouts of 4 min duration with 3 min active recovery between bouts. Soccer player performance was evaluated using five field tests: a) 30m sprint, b) throw-in for distance, c) Illinois Agility Test, d) dribbling the ball and e) horizontal jump before, in the middle and after the implementation of both game situations. Heart rate was monitored during the entire testing session. Each game was also filmed to measure soccer movements within the game. The ANOVA analysis indicated that the three-a- side games displayed significantly higher heart rate values compared with the six-a-side games (p < 0.05). The number of short passes, kicks, tackles, dribbles and scoring goals were significantly higher during the three-a-side compared with the six-a-side game condition (p < 0. 05) while players performed more long passes and headed the ball more often during the six-a-side (p < 0.05). After the three-a-side games, there was a significant decline in sprint and agility performance (p < 0.05), while after both game conditions significant alterations in the throw-in and the horizontal jump performance were observed (p < 0.05). The results of the present study indicated that three-a-side games provide higher stimulus for physical conditioning and technical improvement than six-a-side games and their use for training young soccer players is recommended. Key pointsThree-a-side games display higher HR compared with six-a-side games.In the three-a-side games players performed more short passes, kicks, dribbles, tackles and scored more goals

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.

Five-week sensory motor training program improves functional performance and postural control in young male soccer players - A blind randomized clinical trial.

PubMed

Heleno, Lucas Rafael; da Silva, Rubens A; Shigaki, Leonardo; Araújo, Cynthia Gobbi Alves; Coelho Candido, Cristiane Regina; Okazaki, Victor Hugo Alves; Frisseli, Ariobaldo; Macedo, Christiane de S Guerino

2016-11-01

Sensory motor training programs are used in the rehabilitation and prevention of injuries among soccer players. Inconsistencies are found in the literature regarding the duration of the protocols and the exercises and equipment used. To evaluate the benefits of a five-week sensory motor training program on the functional performance and postural control of young soccer players. The study sample comprised 22 young male soccer players who were evaluated using: the Figure-of-Eight Test (F8), Side Hop Test (SHT), Star Excursion Balance Test (SEBT), and a force platform. The players were randomly divided into a control group (N = 10), who continued their soccer practice sessions and an intervention group (N = 12), who continued their soccer practice sessions and were also enrolled in a supervised five-week sensory motor training program. After the five-week training program, the intervention group obtained significant results in the F8, SHT and SEBT, as well as in the following parameters: area of pressure of sway center (COP), mean velocity and mean frequency of COP. The five-week sensory motor training program, carried out with easily available and low cost equipment, was effective at improving functional performance and postural control in young soccer players. Copyright © 2016 Elsevier Ltd. All rights reserved.

Coaches' interpersonal style, basic psychological needs and the well- and ill-being of young soccer players: a longitudinal analysis.

PubMed

Balaguer, Isabel; González, Lorena; Fabra, Priscila; Castillo, Isabel; Mercé, Juan; Duda, Joan L

2012-01-01

This study entailed a longitudinal test of basic psychological needs theory, a sub-theory in the self-determination framework (Deci & Ryan, 2000), in young soccer players. We examined whether changes in soccer players' perceptions of the coaches' interpersonal style (autonomy supportive and controlling) predicted changes in the players' need satisfaction/need thwarting, and in turn, variability in their reported subjective vitality and burnout over the course of a season. Young male soccer players (M = 12.58 ± 0.54 years) completed a questionnaire at two time points in the season [n(T1) = 725; n(T2) = 597]. Changes in the players' perceptions of an autonomy supportive environment significantly predicted changes in psychological need satisfaction (positively) and in psychological need thwarting (negatively). Changes in psychological need satisfaction positively predicted changes in subjective vitality and negatively related to cross-time variation in global burnout scores. In contrast, changes in the players' perceptions of a controlling coach-created environment were positively associated with changes in psychological need thwarting that corresponded to increases in player burnout. Finally, results provided support for the assumed mediational roles of psychological need satisfaction and need thwarting in the social environment to well- and ill-being relationships.

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.

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.

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.

Appropriate interpretation of aerobic capacity: allometric scaling in adult and young soccer players

PubMed Central

Chamari, K; Moussa-Chamari, I; Boussaidi, L; Hachana, Y; Kaouech, F; Wisloff, U

2005-01-01

Objective: To compare aerobic capacity of young and adult elite soccer players using appropriate scaling procedures. Methods: Twenty four male adult (mean (SD) age 24 (2) years, weight 75.7 (7.2) kg, VO2MAX 66.6 (5.2) ml/lbm/min, where lbm is lean body mass in kg) and 21 youth (14 (0.4) years, 60.2 (7.3) kg, 66.5 (5.9) ml/lbm/min) elite soccer players took part in the study. Allometric equations were used to determine the relation between maximal and submaximal oxygen cost of running (running economy) and body mass. Results: Maximal and submaximal oxygen uptake increased in proportion to body mass raised to the power of 0.72 (0.04) and 0.60 (0.06) respectively. The VO2MAX of adult players was similar to that of the youth players when expressed in direct proportion to body mass—that is, ml/kg/min—but 5% higher (p<0.05) when expressed using appropriate procedures for scaling. Conversely, compared with seniors, youth players had 13% higher (p<0.001) energy cost of running—that is, poorer running economy—when expressed as ml/kg/min but not when expressed according to the scaling procedures. Conclusions: Compared with the youth soccer players, VO2MAX in the seniors was underestimated and running economy overestimated when expressed traditionally as ml/lbm/min. The study clearly shows the pitfalls in previous studies when aerobic capacity was evaluated in subjects with different body mass. It further shows that the use of scaling procedures can affect the evaluation of, and the resultant training programme to improve, aerobic capacity. PMID:15665205

Comparison of the Kinematic Patterns of Kick Between Brazilian and Japanese Young Soccer Players

PubMed Central

Pereira Santiago, Paulo Roberto; Palucci Vieira, Luiz Henrique; Barbieri, Fabio Augusto; Moura, Felipe Arruda; Exel Santana, Juliana; de Andrade, Vitor Luiz; de Souza Bedo, Bruno Luiz; Cunha, Sergio Augusto

2016-01-01

Background Kicking performance is the most studied technical action in soccer and lower limbs kinematics is closely related to success in kicking, mainly because they are essential in imparting high velocity to the ball. Previous studies demonstrated that soccer leagues in different countries exhibit different physical demands and technical requirements during the matches. However, evidencewhether nationality has any influence in the kinematics of soccer-related skills has not yet been reported. The nationality of the players is an aspect that might be also relevant to the performance in kicking. Objectives The aim of this study was to compare the lower limbs kinematic patterns during kicking, between Brazilian and Japanese young top soccer players. Patients and Methods Seven Brazilian (GA) and seven Japanese (GB) U-17 players performed 15 side-foot kicks each, with a distance of 20 m away from the goal, aiming a target of 1 × 1 m in upper corner, constrained by a defensive wall (1.8 × 2 m). Four digital video cameras (120 Hz) recorded the performance for further 3D reconstruction of thigh, shank and foot segments of both kicking and support limbs. The selected kicking cycle was characterized by the toe-off of the kicking limb to the end of the kicking foot when it came in contact with the ball. Stereographical projection of each segment was applied to obtain the representative curves of kicking as function of time for each participant in each trial. Cluster analysis was performed to identify the mean GA and GB curves for each segment. Silhouette coefficient (SC) was calculated, in order to determine the degree of separation between the two groups’ curves. Results Comparison between the median confidence intervals of the SC showed no differences between groups as regards lower limb patterns of movements. Task accuracy was determined by the relative frequency that the ball reached the target for all attempts and no differences were found (GA: 10.48 ± 14.33%; GB

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.

Effect of High-Speed Strength Training on Physical Performance in Young Soccer Players of Different Ages.

PubMed

Rodríguez-Rosell, David; Franco-Márquez, Felipe; Mora-Custodio, Ricardo; González-Badillo, Juan José

2017-09-01

Rodríguez-Rosell, D, Franco-Márquez, F, Mora-Custodio, R, and González-Badillo, JJ. Effect of high-speed strength training on physical performance in young soccer players of different ages. J Strength Cond Res 31(9): 2498-2508, 2017-The aim of the present study was to compare the effectiveness of low-load, low-volume weight training combined with plyometrics on strength, sprint, and jump performance in soccer players of different ages. Eighty-six soccer players from the same academy were categorized into 3 groups by age (under 13 years, U13, n = 30; under 15, U15, n = 28; and under 17, U17, n = 28) and then randomly assigned into 2 subgroups: a strength training group (STG) and a control group (CG). The strength training program was performed twice a week for 6 weeks and consisted of full squats (load: 45-60% 1 repetition maximum; volume: 3 set of 8-4 repetitions), jumps, and straight line sprint exercises. After training intervention, the STGs showed significant improvements in maximal strength (7.5-54.5%; p < 0.001), jump height (5.7-12.5%; p <0.01-0.001), and sprint time (-3.7 to -1.2%; p ≤0.05-0.001), whereas no significant gains were found for any variable in the CGs. Comparison between experimental groups resulted in a greater magnitude of change for U13 compared with U15 (effect sizes [ES]: 0.10-0.53) and U17 (ES: 0.14-1.41) soccer players in most variables, whereas U15 showed higher improvements in jump and strength parameters than U17 (ES: 0.25-0.90) soccer players. Thus, although our results indicates that a combined weight training and plyometrics program may be effective in eliciting gains in strength, jump, and sprint in soccer players of different ages, the training program used appears to be generally less effective as the age of the soccer players increased. Therefore, it appears that training characteristics (mainly volume, intensity, and type of exercise) should be modified in relation to maturity status and initial strength level.

Kicking Performance in Young U9 to U20 Soccer Players: Assessment of Velocity and Accuracy Simultaneously

ERIC Educational Resources Information Center

Vieira, Luiz H. P.; Cunha, Sérgio A.; Moraes, Renato; Barbieri, Fabio A.; Aquino, Rodrigo; Oliveira, Lucas de P.; Navarro, Martina; Bedo, Bruno L. S.; Santiago, Paulo R. P.

2018-01-01

Purpose: The purpose of this study was to compare the kicking performance of young soccer players in the U9 to U20 age groups. Method: Three hundred and sixty-six Brazilian players were evaluated on an official pitch using three-dimensional kinematics to measure (300 Hz) ball velocity (V[subscript ball]), foot velocity (V[subscript foot]),…

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.

Comparison of technical and physical activities between 8 vs. 8 and 11 vs. 11 games in young Korean soccer players.

PubMed

Oh, Seong Hwan; Joo, Chang Hwa

2018-04-01

The aims of this study were to examine the differences in technical aspects and physical demands between small-size games (SSG; 8 vs. 8) and regular-size games (RSG; 11 vs. 11) in young Korean soccer players. Seventy-nine young soccer players from 6 teams (U-12) volunteered to participate in the study. The players completed 4 games (2 SSG, 62×51 m, and 2 RSG, 80×54 m) in 2 days. Each game was filmed to evaluate technical actions. Physical demand variables were measured using global positioning system technology. SSG showed significantly greater numbers of technical plays among 17 variables when compared to RSG ( P <0.05). The players covered significantly greater total distance during low-, moderate-, and high-speed running and sprinting in SSG than in RSG ( P <0.05). Higher numbers of high-intensity activities (repeated high-intensity efforts, explosive efforts, decelera-tions, accelerations, and sprinting) were observed in SSG compared to RSG ( P <0.05). Mean heart rate was also higher in SSG than in RSG ( P <0.05). Despite the greater physical demands during SSG, the exercise intensity was similar to that reported in previous studies. Therefore, the SSG format applied in the present study can be a suitable official game format for Korean young soccer players, resulting in significantly greater exposure to technical plays without excessive physical demands.

Comparison of technical and physical activities between 8 vs. 8 and 11 vs. 11 games in young Korean soccer players

PubMed Central

Oh, Seong Hwan; Joo, Chang Hwa

2018-01-01

The aims of this study were to examine the differences in technical aspects and physical demands between small-size games (SSG; 8 vs. 8) and regular-size games (RSG; 11 vs. 11) in young Korean soccer players. Seventy-nine young soccer players from 6 teams (U-12) volunteered to participate in the study. The players completed 4 games (2 SSG, 62×51 m, and 2 RSG, 80×54 m) in 2 days. Each game was filmed to evaluate technical actions. Physical demand variables were measured using global positioning system technology. SSG showed significantly greater numbers of technical plays among 17 variables when compared to RSG (P<0.05). The players covered significantly greater total distance during low−, moderate−, and high-speed running and sprinting in SSG than in RSG (P<0.05). Higher numbers of high-intensity activities (repeated high-intensity efforts, explosive efforts, decelera-tions, accelerations, and sprinting) were observed in SSG compared to RSG (P<0.05). Mean heart rate was also higher in SSG than in RSG (P<0.05). Despite the greater physical demands during SSG, the exercise intensity was similar to that reported in previous studies. Therefore, the SSG format applied in the present study can be a suitable official game format for Korean young soccer players, resulting in significantly greater exposure to technical plays without excessive physical demands. PMID:29740560

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.

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.

Effects of Combined Resistance Training and Plyometrics on Physical Performance in Young Soccer Players.

PubMed

Franco-Márquez, F; Rodríguez-Rosell, D; González-Suárez, J M; Pareja-Blanco, F; Mora-Custodio, R; Yañez-García, J M; González-Badillo, J J

2015-11-01

This study aimed to determine the effects of combined resistance training and plyometrics on physical performance in under-15 soccer players. One team (n=20) followed a 6-week resistance training program combined with plyometrics plus a soccer training program (STG), whereas another team (n=18) followed only the soccer training (CG). Strength training consisted of full squats with low load (45-60% 1RM) and low-volume (2-3 sets and 4-8 repetitions per set) combined with jumps and sprints twice a week. Sprint time in 10 and 20 m (T10, T20, T10-20), CMJ height, estimated one-repetition maximum (1RMest), average velocity attained against all loads common to pre- and post-tests (AV) and velocity developed against different absolute loads (MPV20, 30, 40 and 50) in full squat were selected as testing variables to evaluate the effects of the training program. STG experienced greater gains (P<0.05) in T20, CMJ, 1RMest, AV and MPV20, 30, 40 and 50 than CG. In addition, STG showed likely greater effects in T10 and T10-20 compared to CG. These results indicate that only 6 weeks of resistance training combined with plyometrics in addition to soccer training produce greater gains in physical performance than typical soccer training alone in young soccer players. © Georg Thieme Verlag KG Stuttgart · New York.

Concussion among female middle-school soccer players.

PubMed

O'Kane, John W; Spieker, Amy; Levy, Marni R; Neradilek, Moni; Polissar, Nayak L; Schiff, Melissa A

2014-03-01

Despite recent increased awareness about sports concussions, little research has evaluated concussions among middle-school athletes. To evaluate the frequency and duration of concussions in female youth soccer players and to determine if concussions result in stopping play and seeking medical care. Prospective cohort study from March 2008 through May 2012 among 4 soccer clubs from the Puget Sound region of Washington State, involving 351 elite female soccer players, aged 11 to 14 years, from 33 randomly selected youth soccer teams. Of the players contacted, 83.1% participated and 92.4% completed the study. Concussion cumulative incidence, incidence rate, and description of the number, type, and duration of symptoms. We inquired weekly about concussion symptoms and, if present, the symptom type and duration, the event resulting in symptom onset, and whether the player sought medical attention or played while symptomatic. Among the 351 soccer players, there were 59 concussions with 43 742 athletic exposure hours. Cumulative concussion incidence was 13.0% per season, and the incidence rate was 1.2 per 1000 athletic exposure hours (95% CI, 0.9-1.6). Symptoms lasted a median of 4.0 days (mean, 9.4 days). Heading the ball accounted for 30.5% of concussions. Players with the following symptoms had a longer recover time than players without these symptoms: light sensitivity (16.0 vs 3.0 days, P = .001), emotional lability (15.0 vs 3.5 days, P = .002), noise sensitivity (12.0 vs 3.0 days, P = .004), memory loss (9.0 vs 4.0 days, P = .04), nausea (9.0 vs 3.0 days, P = .02), and concentration problems (7.0 vs 2.0 days, P = .02). Most players (58.6%) continued to play with symptoms, with almost half (44.1%) seeking medical attention. Concussion rates in young female soccer players are greater than those reported in older age groups, and most of those concussed report playing with symptoms. Heading the ball is a frequent precipitating event. Awareness

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

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

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.

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.

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.

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

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.

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.

Increase in upper extremity fractures in young male soccer players in the Netherlands, 1998-2009.

PubMed

de Putter, C E; van Beeck, E F; Burdorf, A; Borsboom, G J J M; Toet, H; Hovius, S E R; Selles, R W

2015-08-01

Young male soccer players have been identified as a target group for injury prevention, but studies addressing trends and determinants of injuries within this group are scarce. The goal of this study was to analyze age-specific trends in hospital-treated upper extremity fractures (UEF) among boys playing soccer in the Netherlands and to explore associated soccer-related factors. Data were obtained from a national database for the period 1998-2009. Rates were expressed as the annual number of UEF per 1000 soccer players. Poisson's regression was used to explore the association of UEF with the number of artificial turf fields and the number of injuries by physical contact. UEF rates increased significantly by 19.4% in boys 5-10 years, 73.2% in boys 11-14 years, and 38.8% in boys 15-18 years old. The number of injuries by physical contact showed a significant univariate association with UEF in boys 15-18 years old. The number of artificial turf fields showed a significant univariate association with UEF in all age groups, and remained significant for boys aged 15-18 years in a multivariate model. This study showed an increase of UEF rates in boys playing soccer, and an independent association between artificial turf fields and UEF in the oldest boys. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

NUTRITIONAL INTAKE AND NUTRITIONAL STATUS IN ELITE MEXICAN TEENAGERS SOCCER PLAYERS OF DIFFERENT AGES.

PubMed

Hidalgo y Teran Elizondo, Roberto; Martín Bermudo, Francisco Manuel; Peñaloza Mendez, Ricardo; Berná Amorós, Genoveva; Lara Padilla, Eleazar; Berral de la Rosa, Francisco José

2015-10-01

nutritional intake and status of soccer players has attracted not much research attention. Many soccer players follow an inadequate nutritional intake and have a poor nutritional status. This is relevant in youngsters soccer players, in order to improve performance and promote healthy dietary practices. analyze anthropometric characterizes, evaluate nutritional intake and status, dietary habits and pre- and post-exercise meals in elite teenagers soccer players. seventy-two young male soccer players (15-20 years) from four junior teams of a soccer Club from the Mexican National Soccer League were measured for height, seat height, weight, 6 skinfolds, 6 diameters and 7 circumferences, height-for-age and BMI-for-age values. Skin, adipose, muscle, bone and residual tissue masses were calculated with the Ross and Kerr equation. Resting energy expenditure and intake was also measured. Daily dietary intake was self-recorded for 4 consecutive days (excluding the match day) using a digital food-weighing scale and a food record questionnaire. Dietary analysis was performed using the NutriBase 7 Clinical software. Several biochemical values were determined. One-way analysis of variance (ANOVA) and post hoc testing was performed using t-tests with a Bonferroni correction. all soccer players were within the normal range values for anthropometric parameters studies, when compared with other adolescent elite soccer teams. Values of plasma glucose, urea, creatinine, uric acid, lipid profile and total proteins were within normal range for young adult population, although albumin levels were high. Moreover, 14% and 20% of soccer players presented hyperuricemia and elevated total cholesterol levels respectively. Energy expenditure and intake were within normal range for all teenager elite soccer players. However, two teams shower significant lower intakes than demands. All macronutrient intakes were within recommendations, except protein that was higher. Micronutrient intake exceeded

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

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.

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

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.

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.

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

Soccer Players Cultural Capital and Its Impact on Migration

PubMed Central

Leskošek, Bojan; Vodičar, Janez; Topič, Mojca Doupona

2016-01-01

Abstract The purpose of this study was to identify factors that constituted the cultural capital among soccer players. We assumed that in the increasingly globalized world of professional soccer, a player’s success would often depend on migrating and adjusting to life in other countries. Willingness to migrate and successful adjustment are tied to player’s previous attitudes and/or behaviours (habitus), significant support from others, including family members, and previous experiences and success in sports and education. Our hypothesised model of the cultural capital was based on the Pierre Bourdieu’s theoretical framework. It consisted of 26 variables related to three sets of factors: soccer experiences, a family context and support, and educational achievements of the players and their parents. The model was tested using a sample of 79 current soccer coaches who also had been players at the elite level. A factor analysis was used to empirically verify the content of the hypothetical model of the soccer players’ cultural capital. Nine latent factors were extracted and together, they accounted for 55.01% of the total model variance. Individual factors obtained showed a sufficient level of substantial connection. The Cronbach’s alpha value of 0.77 confirmed the internal consistency of the operationalised variables in the hypothetical model. In addition, the impact of these aforementioned life dimensions on the migration of soccer players was studied. The results of the binary logistic regression analysis showed that the first factor of the hypothetical model (F1) had 2.2 times and the second factor (F8) had 3.9 times higher odds for migration abroad. Sociocultural findings using this new assessment approach could help create better “success conditions” in the talent development of young players. PMID:28031770

Complex network study of Brazilian soccer players

NASA Astrophysics Data System (ADS)

Onody, Roberto N.; de Castro, Paulo A.

2004-09-01

Although being a very popular sport in many countries, soccer has not received much attention from the scientific community. In this paper, we study soccer from a complex network point of view. First, we consider a bipartite network with two kinds of vertices or nodes: the soccer players and the clubs. Real data were gathered from the 32 editions of the Brazilian soccer championship, in a total of 13411 soccer players and 127 clubs. We find a lot of interesting and perhaps unsuspected results. The probability that a Brazilian soccer player has worked at N clubs or played M games shows an exponential decay while the probability that he has scored G goals is power law. Now, if two soccer players who have worked at the same club at the same time are connected by an edge, then a new type of network arises (composed exclusively by soccer player nodes). Our analysis shows that for this network the degree distribution decays exponentially. We determine the exact values of the clustering coefficient, the assortativity coefficient and the average shortest path length and compare them with those of the Erdös-Rényi and configuration model. The time evolution of these quantities are calculated and the corresponding results discussed.

Coach autonomy support and quality of sport engagement in young soccer players.

PubMed

Alvarez, María Sol; Balaguer, Isabel; Castillo, Isabel; Duda, Joan L

2009-05-01

Based on the self-determination theory (Ryan & Deci, 2000), this study tested a model of the assumed sequential relationships between perceived autonomy support, psychological need satisfaction, self-determined motivation, and enjoyment/boredom. The hypothesized mediational roles of psychological need satisfaction and self-determined motivation were also studied. In a sample of 370 young male soccer players, path analysis results offered support for the proposed model. Total mediation was supported in the case of the psychological need satisfaction in the relationship between autonomy support and self-determined motivation, and partial mediation for self-determined motivation in the links between psychological need satisfaction and enjoyment (positive) and boredom (negative). Implications of autonomy-supportive behaviors provided by coaches for the quality of sport involvement among young athletes are discussed.

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

PubMed Central

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

2015-01-01

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 η2 > 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 points Performing jumping rope exercises

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

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.

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.

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.

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.

The Prevalence of Injuries in Professional Turkish Soccer Players

ERIC Educational Resources Information Center

Yamaner, Faruk; Gumusdag, Hayrettin; Kartal, Alparslan; Gumus, M.; Gullu, A.; Imamoglu, O.

2011-01-01

Study aim: To assess the prevalence and anatomical sites of injuries in professional soccer players in one game season. Material and methods: A cohort of 510 professional male soccer players consisting of 48 goalkeepers, 194 defence players, 189 mid-field players and 79 forward players of the 1st and 2nd Turkish Professional Soccer Leagues in…

Effects of in-season low-volume high-intensity plyometric training on explosive actions and endurance of young soccer players.

PubMed

Ramírez-Campillo, Rodrigo; Meylan, César; Alvarez, Cristian; Henríquez-Olguín, Carlos; Martínez, Cristian; Cañas-Jamett, Rodrigo; Andrade, David C; Izquierdo, Mikel

2014-05-01

Integrating specific training methods to improve explosive actions and endurance in youth soccer is an essential part of players' development. This study investigated the efficiency of short-term vertical plyometric training program within soccer practice to improve both explosive actions and endurance in young soccer players. Seventy-six players were recruited and assigned either to a training group (TG; n = 38; 13.2 ± 1.8 years) or a control group (CG; n = 38; 13.2 ± 1.8 years) group. All players trained twice per week, but the TG followed a 7-week plyometric program implemented within soccer practice, whereas the CG followed regular practice. Twenty-meter sprint time (20-m), Illinois agility test time, countermovement jump (CMJ) height, 20- (RSI20) and 40- (RSI40) cm drop jump reactive strength index, multiple 5 bounds distance (MB5), maximal kicking test for distance (MKD), and 2.4-km time trial were measured before and after the 7-week period. Plyometric training induced significant (p ≤ 0.05) and small to moderate standardized effect (SE) improvement in the CMJ (4.3%; SE = 0.20), RSI20 (22%; SE = 0.57), RSI40 (16%; SE = 0.37), MB5 (4.1%; SE = 0.28), Illinois agility test time (-3.5%, SE = -0.26), MKD (14%; SE = 0.53), 2.4-km time trial (-1.9%; SE = -0.27) performances but had a trivial and nonsignificant effect on 20-m sprint time (-0.4%; SE = -0.03). No significant improvements were found in the CG. An integrated vertical plyometric program within the regular soccer practice can substitute soccer drills to improve most explosive actions and endurance, but horizontal exercises should also be included to enhance sprinting performance.

Cortical thinning in former professional soccer players.

PubMed

Koerte, Inga K; Mayinger, Michael; Muehlmann, Marc; Kaufmann, David; Lin, Alexander P; Steffinger, Denise; Fisch, Barbara; Rauchmann, Boris-Stephan; Immler, Stefanie; Karch, Susanne; Heinen, Florian R; Ertl-Wagner, Birgit; Reiser, Maximilian; Stern, Robert A; Zafonte, Ross; Shenton, Martha E

2016-09-01

Soccer is the most popular sport in the world. Soccer players are at high risk for repetitive subconcussive head impact when heading the ball. Whether this leads to long-term alterations of the brain's structure associated with cognitive decline remains unknown. The aim of this study was to evaluate cortical thickness in former professional soccer players using high-resolution structural MR imaging. Fifteen former male professional soccer players (mean age 49.3 [SD 5.1] years) underwent high-resolution structural 3 T MR imaging, as well as cognitive testing. Fifteen male, age-matched former professional non-contact sport athletes (mean age 49.6 [SD 6.4] years) served as controls. Group analyses of cortical thickness were performed using voxel-based statistics. Soccer players demonstrated greater cortical thinning with increasing age compared to controls in the right inferolateral-parietal, temporal, and occipital cortex. Cortical thinning was associated with lower cognitive performance as well as with estimated exposure to repetitive subconcussive head impact. Neurocognitive evaluation revealed decreased memory performance in the soccer players compared to controls. The association of cortical thinning and decreased cognitive performance, as well as exposure to repetitive subconcussive head impact, further supports the hypothesis that repetitive subconcussive head impact may play a role in early cognitive decline in soccer players. Future studies are needed to elucidate the time course of changes in cortical thickness as well as their association with impaired cognitive function and possible underlying neurodegenerative process.

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.

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

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.

[Doping practices and behaviours among Ivorian soccer players].

PubMed

Dah, Cyrille; Bogui, Pascal; Yavo, Jean-Claude; Gourouza, Issa; Ouattara, Soualiho; Keita, Mustapha

2002-01-01

We have conducted a survey of doping among soccer players in Côte d'Ivoire with a representative sample of 150 soccer players who filled out an anonymous questionnaire. The aim of this survey was to get a clearer picture of doping in Ivorian soccer in order to suggest preventive actions against doping. The results of this study showed that doping was known by the Ivorian soccer players; about 18.7% admitted to the use of doping substances, 42% recognised that they felt tempted by doping, while 38% knew another soccer player who had already used a doping substance. Government and sports organisations should recognize the importance of education and information in the antidoping campaign and agree on effective preventive as well as repressive strategies.

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

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

Leadership Power Perceptions of Soccer Coaches and Soccer Players According to Their Education

PubMed Central

Konter, Erkut

2012-01-01

The purpose of this study was to analyze the leadership power perceptions of soccer coaches and soccer players according to their educational levels. Data were collected from 165 male soccer coaches and 870 male soccer players. Adapted versions of the “Power in Soccer Questionnaire-Other”, the “Power in Soccer Questionnaire-Self” and an “information form” were used for data collection, and collected data were analyzed by the Kruskal-Wallis and the Mann-Whitney Tests. Analysis of the Power in Soccer Questionnaire-Other revealed significant differences between soccer players’ level of education and their perception of Coercive Power (p<.003), and no significant differences related to Referent Power, Legitimate Power and Expert Power. Analysis of the Power in Soccer Questionnaire-Self also revealed the only significant difference between coaches’ level of education and their perception of Legitimate Power (p<.001), and no significant differences with regard to others. Different perception of leadership powers between coaches and players might create communication and performance problems in soccer. PMID:23486640

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.

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.

The Yo-Yo intermittent recovery test level 1 is reliable in young high-level soccer players.

PubMed

Deprez, D; Fransen, J; Lenoir, M; Philippaerts, Rm; Vaeyens, R

2015-03-01

The aim of the study was to investigate test reliability of the Yo-Yo intermittent recovery test level 1 (YYIR1) in 36 high-level youth soccer players, aged between 13 and 18 years. Players were divided into three age groups (U15, U17 and U19) and completed three YYIR1 in three consecutive weeks. Pairwise comparisons were used to investigate test reliability (for distances and heart rate responses) using technical error (TE), coefficient of variation (CV), intra-class correlation (ICC) and limits of agreement (LOA) with Bland-Altman plots. The mean YYIR1 distances for the U15, U17 and U19 groups were 2024 ± 470 m, 2404 ± 347 m and 2547 ± 337 m, respectively. The results revealed that the TEs varied between 74 and 172 m, CVs between 3.0 and 7.5%, and ICCs between 0.87 and 0.95 across all age groups for the YYIR1 distance. For heart rate responses, the TEs varied between 1 and 6 bpm, CVs between 0.7 and 4.8%, and ICCs between 0.73 and 0.97. The small ratio LOA revealed that any two YYIR1 performances in one week will not differ by more than 9 to 28% due to measurement error. In summary, the YYIR1 performance and the physiological responses have proven to be highly reliable in a sample of Belgian high-level youth soccer players, aged between 13 and 18 years. The demonstrated high level of intermittent endurance capacity in all age groups may be used for comparison of other prospective young soccer players.

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

The peak velocity derived from the Carminatti Test is related to physical match performance in young soccer players.

PubMed

Fernandes-da-Silva, Juliano; Castagna, Carlo; Teixeira, Anderson Santiago; Carminatti, Lorival José; Guglielmo, Luiz Guilherme Antonacci

2016-12-01

The aim of this study was to examine the relationship between the peak velocity derived from the Carminatti Test (T-CAR) (PV T-CAR ) and physical match performance in young soccer players. Thirty-three youth soccer players were recruited from 2 non-professional clubs. Friendly matches and small-sided game were performed. Physical match demands were assessed using Global Positioning System (GPS) technology. On a separate occasion, the players were submitted to the T-CAR. Players were categorised into 3 groups based on their T-CAR performance: Low (PV T-CAR  ≤ P33), Intermediate (P33 > PV T-CAR  < P66) and High (PV T-CAR  ≥ P66). The PV T-CAR (15.5 ± 0.7 km·h -1 ) was significantly related to high-intensity activities (HIA; r = 0.78, P < 0.001), high-intensity running (HIR; r = 0.66, P < 0.001), sprinting (r = 0.62, P < 0.001) and total distance (TD) covered (r = 0.47, P < 0.01) during friendly matches. The PV T-CAR was strongly correlated with the amount of HIA (r = 0.81, P < 0.001), HIR (r = 0.85, P < 0.001) and TD covered (r = 0.81, P < 0.001) during small-sided game. No significant correlation was observed between the PV T-CAR and distance of sprinting (r = 0.49, P = 0.067) during small-side game. Furthermore, players in the High group covered significantly more TD (10%) and did more HIA (42%), sprinting (31%) and HIR (25%) during friendly matches compared to the players classified as having Low performance on the T-CAR. These differences still remained after adjusting for chronological age (CA), maturity and body size. In conclusion, the current study gives empirical support to the ecological and construct validity of this novel field test (T-CAR) as an indicator of match-related physical performance in young soccer players during pubertal years.

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

Effects of Bout Duration on Players' Internal and External Loads During Small-Sided Games in Young Soccer Players.

PubMed

Köklü, Yusuf; Alemdaroğlu, Utku; Cihan, Hamit; Wong, Del P

2017-11-01

To investigate the effects of different bout durations on internal and external loads of young soccer players during different small-sided games (SSGs). Fifteen young male soccer players (average age 17 ± 1 y) participated in 2 vs 2, 3 vs 3, and 4 vs 4 SSGs. All games lasted 12 min playing time in total, but each SSG format further consisted of 4 bout durations: continuous (CON: 1 bout × 12 min) or interval with short (SBD: 6 bouts  × 2 min), medium (MBD: 3 bouts × 4 min), or long (LBD: 2 bouts × 6 min) bout durations. During the SSGs, heart-rate (HR) responses and distance covered in different speed zones (walking and low-intensity, moderate-intensity, and high-intensity running) were measured. Rating of perceived exertion (RPE) and blood lactate (La - ) were determined at the end of each SSG. The SBD format elicited significantly lower %HR max responses compared to LBD and CON in all formats (P < .05). The SBD format also showed significantly shorter distances covered in walking and greater distances covered in moderate-intensity running, as well as significantly greater total distance covered compared to LBD and CON in all formats (P < .05). In addition, LBD produced significantly lower La - and RPE responses than SBD and CON in all formats (P < .05). These results suggest that coaches and sport scientists who want to achieve higher internal loads could use SBD and CON timing protocols, while those who want to achieve higher external loads might prefer to use SBD and MBD when planning all SSG formats.

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.

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

Nutritional intake in soccer players of different ages.

PubMed

Ruiz, Fátima; Irazusta, Amaia; Gil, Susana; Irazusta, Jon; Casis, Luis; Gil, Javier

2005-03-01

The purpose of this study was to evaluate the dietary practices of soccer players of different ages. The diets of the members of four soccer teams (mean ages of 14.0, 15.0, 16.6 and 20.9 years, respectively) were examined. Our results show that the caloric intake per kilogram of body mass was significantly higher among the youngest players when compared with the adult players (P < 0.05). The contribution of carbohydrates to total energy intake was lower than that recommended for athletes. This contribution decreased with age from 47.4% of total energy intake for the 14-year-olds to 44.6% for the adult players. No significant differences in protein or total fat intake were detected among the teams examined. Overall, our results show that the nutritional intake of the soccer players was not optimal, and that this intake was poorer among the adult players than among the adolescents. On the basis of our results, we recommended that nutritional education should be given to soccer players at an early age and should continue throughout adolescence, not only with a view to improving performance but also to promoting more healthy dietary practices in the long term.

Commitment, enjoyment and motivation in young soccer competitive players.

PubMed

Garcia-Mas, Alexandre; Palou, Pere; Gili, Margarita; Ponseti, Xavier; Borras, Pere A; Vidal, Josep; Cruz, Jaume; Torregrosa, Miquel; Villamarín, Francisco; Sousa, Catarina

2010-11-01

Building upon Deci's and Ryan (1985) Self-determination theory as well as the sportive behavioral correlates of the model of Commitment (Scanlan et al., 1976), this study tries to establish the relationship between motivation and commitment in youth sport. For this purpose 454 young competitive soccer players answered the Sport Motivation Scale (SMS) and the Sport Commitment Questionnaire (SCQ) during the regular season. The SMS measures the three dimensions of the Motivational continuum (the Amotivation, the Extrinsic Motivation and the Intrinsic Motivation). The SCQ measures the Sportive Commitment and its composing factors such as the Enjoyment, the Alternatives to the sport, and the Social Pressure. Our findings provided a clear pattern of the influence of motivation in sport enjoyment and commitment, outlining the positive contribution of intrinsic and extrinsic motivation to enjoyment and commitment. Amotivation, contributes positively to alternatives to sport and negatively to enjoyment and commitment, It should be noted that extrinsic motivation has a higher contribution to enjoyment whereas intrinsic motivation has a higher contribution to commitment.

Muscle injuries of the lower extremity: a comparison between young and old male elite soccer players.

PubMed

Svensson, Kjell; Alricsson, Marie; Karnebäck, Gustav; Magounakis, Theo; Werner, Suzanne

2016-07-01

The aim of this study was to make a comparison between players in two age groups in an elite male soccer team regarding injury localisation within the muscle-tendon unit, injury size and muscle group in terms of muscle injuries of the lower extremity. Cohort study based on data collected from a Swedish elite male soccer team during the seasons 2007-2012. In total, 145 muscle injuries were included. Injury localisation to the tendon or muscle, the size of haematoma and the affected muscle group were assessed using ultrasound. Age comparison was made between younger players (≤23 years) and older players (>23 years). No difference regarding injury localisation to either the tendon or the muscle, or the size of haematoma between the two age groups was found. However, the older group of players suffered a significantly higher number of injuries to the triceps surae than the younger players (p = 0.012). In a Swedish team of male soccer players at elite level, there was no difference between players 23 years or younger and players older than 23 years, in terms of injury distribution to muscles or tendons. Players older than 23 years sustained more injuries to triceps surae when compared with players 23 years or younger. The clinical relevance is to pay attention to muscle function of triceps surae in older players and to screen those players who may need an injury prevention programme. II.

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.

Comparative study of the femoroacetabular impingement (FAI) prevalence in male semiprofessional and amateur soccer players.

PubMed

Lahner, Matthias; Walter, Philipp Alexander; von Schulze Pellengahr, Christoph; Hagen, Marco; von Engelhardt, Lars Victor; Lukas, Carsten

2014-08-01

Femoroacetabular impingement (FAI) represents a novel approach to the mechanical etiology of hip osteoarthritis. The cam-type femoroacetabular impingement deformity occurs frequently in young male athletes. The aim of our study was to evaluate the prevalence of FAI in male semiprofessional soccer players using clinical examination and magnetic resonance imaging (MRI), compared to amateur soccer players. In MRI, the α angle of Nötzli is determined for quantifying FAI. According to power analysis, a total of 22 asymptomatic semiprofessional soccer players with a median of 23.3 years of age (range 18-30 years) and 22 male amateur soccer players with a median of 22.5 years of age (control group, range 18-29 years) underwent an MRI to measure the hip α angle of Nötzli. The α angle of the kicking legs of the semiprofessional group and the amateur group were analyzed. The study group was moreover evaluated by the Hip Outcome Score (HOS) and a clinical hip examination including range of motion (ROM) and impingement tests. In the semiprofessional group, 19 soccer players had a right kicking leg and 1 soccer player had a left kicking leg. 2 soccer players kicked with two feet. In the semi-professional group, the mean value of the α angle of the kicking leg (57.3 ± 8.2°) was significantly higher than in the amateur group (51.7 ± 4.8°, P = 0.008). In the semi-professional group, 15 (62.5 %) of 24 kicking legs had an increased α angle >55°, while 5 (27.3 %) kicking legs of the amateur group had an α angle >55°. Five semi professional soccer players had findings in clinical examination, whereof 4 had an increased α angle >55°. No participant of the amateur group showed pathological results in the clinical examination (P = 0.0484). Overall, semiprofessional soccer players had a higher proportion of an increased α angle than the amateur group. Semiprofessional players have a higher prevalence of an increased α angle in the kicking leg than the amateur group at

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

Freedom between the Lines: Clothing Behavior and Identity Work among Young Female Soccer Players

ERIC Educational Resources Information Center

Hendley, Alexandra; Bielby, Denise D.

2012-01-01

Our research examines the relationship among identity, age, gender and athleticism through a study of the association between sports clothing and the identity work of pre-adolescent female soccer players. Based on participant-observation and interviews conducted at three co-ed youth soccer camps, we find that age is an important element of…

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

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

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…

Is the technical performance of young soccer players influenced by hormonal status, sexual maturity, anthropometric profile, and physical performance?

PubMed

Moreira, Alexandre; Massa, Marcelo; Thiengo, Carlos R; Rodrigues Lopes, Rafael Alan; Lima, Marcelo R; Vaeyens, Roel; Barbosa, Wesley P; Aoki, Marcelo S

2017-12-01

The aim of this study was to examine the influence of hormonal status, anthropometric profile, sexual maturity level, and physical performance on the technical abilities of 40 young male soccer players during small-sided games (SSGs). Anthropometric profiling, saliva sampling, sexual maturity assessment (Tanner scale), and physical performance tests (Yo-Yo and vertical jumps) were conducted two weeks prior to the SSGs. Salivary testosterone was determined by the enzyme-linked immunosorbent assay method. Technical performance was determined by the frequency of actions during SSGs. Principal component analyses identified four technical actions of importance: total number of passes, effectiveness, goal attempts, and total tackles. A multivariate canonical correlation analysis was then employed to verify the prediction of a multiple dependent variables set (composed of four technical actions) from an independent set of variables, composed of testosterone concentration, stage of pubic hair and genitalia development, vertical jumps and Yo-Yo performance. A moderate-to-large relationship between the technical performance set and the independent set was observed. The canonical correlation was 0.75 with a canonical R 2 of 0.45. The highest structure coefficient in the technical performance set was observed for tackles (0.77), while testosterone presented the highest structure coefficient (0.75) for the variables of the independent set. The current data suggest that the selected independent set of variables might be useful in predicting SSG performance in young soccer players. Coaches should be aware that physical development plays a key role in technical performance to avoid decision-making mistakes during the selection of young players.

Pattern recall skills of talented soccer players: Two new methods applied.

PubMed

van Maarseveen, Mariëtte J J; Oudejans, Raôul R D; Savelsbergh, Geert J P

2015-06-01

In this study we analyzed the pattern recall skills of talented soccer players by means of two innovative methods of analysis and gaze behavior data. Twenty-two young female soccer players watched video clips of 3 vs. 3 small-sided games and, after occlusion, had to reproduce the positions of the players. Recall performance was measured by calculating the spatial error of the recalled player positions at the moment of occlusion and at consecutive 33ms increments. We analyzed player positions relative to each other, by assessing geometric pattern features in terms of angles between players, and we transformed the data into real-world coordinates to exclude the effects of the 2D perspective in the video clips. The results showed that the participants anticipated the movements of the patterns. In real-world coordinates, the more experienced players anticipated the pattern further in advance than the less experienced players and demonstrated a higher search rate, a shorter fixation duration and a higher fixation order. The differences in recall accuracy between the defensive and offensive elements were not consistent across the methods of analysis and, therefore, we propose that perspective effects of the video clip should be taken into account in further research. Copyright © 2015 Elsevier B.V. All rights reserved.

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

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.

Physiological profiles of Hong Kong élite soccer players.

PubMed Central

Chin, M K; Lo, Y S; Li, C T; So, C H

1992-01-01

Most physiological profiles of élite soccer players originate from Western Europe and North America. Unfortunately, there is a scarcity of descriptive data on the physical characteristics of Asian soccer players. Therefore, the purpose of this study was to evaluate the physiological profiles of élite soccer players in Hong Kong. It was conducted in conjunction with the selection of the Hong Kong team before the 1990 Beijing Asian Games. In all, 24 professional soccer players were selected from a pool of 180 players as subjects for the study. The following means(s.d.) were observed: height 173.4(4.6) cm; weight 67.7(5.0) kg; body fat 7.3(3.0)%; forced vital capacity (FVC) 5.1(0.6) l; maximum oxygen uptake (VO2max) 59.1(4.9) ml kg-1 min-1; anaerobic threshold (AT 80.0(7.2)% of VO2max; alactic power index 13.5(2.4) W kg-1; lactic work index 298(27) J kg-1; peak isokinetic dominant knee extensor and flexor strengths 2.72(0.36) Nm kg-1 and 1.65(0.20) Nm kg-1. On average the physique of Hong Kong soccer players appeared to be smaller and lighter than those found in Europe, which may be one of the key factors that contribute to the lack of success of Hong Kong soccer teams in international competition. PMID:1490221

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.

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

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.

The Physiological Profile of Junior Soccer Players at SSBB Surabaya Bhakti

NASA Astrophysics Data System (ADS)

Nashirudin, M.; Kusnanik, N. W.

2018-01-01

Soccer players are required to have good physical fitness in order to achieve optimum accomplishment; physical fitness stands as the foundation of technical and tactical proficiency as well as the mental maturity during the matches. The purpose of this study was to identify the physiological profile of junior soccer players of SSB Surabaya Bhakti age 16-17. The research was conducted at 20 junior soccer players. This research was quantitative with descriptive analysis. Data were collected by testing of physiological (anaerobic power and capacity including explosive leg power, speed, agility; aerobic capacity: cardiovascular endurance). Data was analyzed using percentage. The result showed that the percentage of explosive leg power of junior soccer players were 30% (good category), speed was 85% (average category), right agility was 90% (average category), left agility was 75% (average category). On the other hand, the aerobic power and capacity of the junior soccer players in this study was 50% (average category). The conclusion of this research is that the physiological profile of junior soccer players at SSB Surabaya Bhakti age 16-17 was majority in average category.

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

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

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.

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

Future Achievements, Passion and Motivation in the Transition from Junior-to-Senior Sport in Spanish Young Elite Soccer Players.

PubMed

Chamorro, José L; Torregrosa, Miquel; Sánchez Oliva, David; García Calvo, Tomás; León, Benito

2016-10-20

Within the context of the transition from junior-to-senior sport, this study aims in first place to explore differences in young Spanish elite soccer players based on the importance given to getting different achievements in their future (including sport, studies and private life) and, in second place, to explore differences among those players in levels of passion, motivation and basic psychological need. 478 elite youth soccer filled out a questionnaire based on the presented theoretical models. A cluster analysis shows a sport oriented group (N = 98) only interested in becoming a professional, a life spheres balance group (N = 288) characterized by balancing the importance of achievements in the sport sphere, as well as in education and a private life and a group (N = 91) only interested in private life achievements. The life spheres balance group shows higher levels of harmonious passion (η2 = .06, F(2, 475) = 9.990, p < .001) than the players of the other groups. The life spheres balance group shows higher levels of autonomous motivation (η2 = .10, F(2, 475) = 13.597, p < .001), autonomy (η2 = .07, F(2, 475) = 6.592, p < .01) and relatedness satisfaction (η2 = .07, F(2, 475) = 5.603, p < .01) than the sport oriented group as well as lower levels of amotivation (η2 = .04, F(2, 475) = 6.665, p < .01) than the private life oriented group. This study suggests players who perceive equal future importance in their life spheres appear to be more resourceful than the other two groups regarding athletes' internal resources, such as passion and motivation, to cope with the transition to professional soccer.

Maturational effect on Functional Movement Screen™ score in adolescent soccer players.

PubMed

Portas, Matthew David; Parkin, Guy; Roberts, James; Batterham, Alan Mark

2016-10-01

The effect of maturity on Functional Movement Screen (FMS) scores in elite, adolescent soccer players was examined. A cross-sectional observational study was completed. Participants were 1163 male English Football League soccer players (age 8-18 years). Players were mid-foundation phase (MF) (U9); late foundation phase (LF) (U10 and U11); early youth development phase (EYD) (U12 and U13); mid-youth development (MYD) phase (U14-U15); Late Youth Development Phase (LYD) (U16) and early professional development phase (EPD) (U18). Age from peak height velocity was estimated and players were categorized as pre- or post-peak height velocity (PHV). To analyse where differences in FMStotal score existed we separated the screen into FMSmove (3 movement tests); FMSflex (2 mobility tests) and FMSstab (2 stability tests). FMStotal median score ranged from 11 at MF to 14 for EPD. There was a substantial increase (10%) in those able to achieve a score of ≥14 on FMStotal in those who were post-PHV compared to pre-PHV. This was explained by a substantial increase in those achieving a score of ≥4 on FMSstab (21%). There was a substantial increase in the proportion of players who achieved the FMStotal threshold of ≥14 with an increase of 47.5 (41.4-53.6)% from the MF phase to the EPD phase due to improvements in FMSmove and FMSstab. PHV and maturity have substantial effects on FMS performance. FMS assessment appears to be invalid for very young players. Findings are relevant to those analyzing movement in soccer players. Copyright © 2015 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

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.

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.

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.

Mental Rotation Performance in Male Soccer Players

PubMed Central

Jansen, Petra; Lehmann, Jennifer; Van Doren, Jessica

2012-01-01

It is the main goal of this study to investigate the visual-spatial cognition in male soccer players. Forty males (20 soccer players and 20 non-athletes) solved a chronometric mental rotation task with both cubed and embodied figures (human figures, body postures). The results confirm previous results that all participants had a lower mental rotation speed for cube figures compared to embodied figures and a higher error rate for cube figures, but only at angular disparities greater than 90°. It is a new finding that soccer–players showed a faster reaction time for embodied stimuli. Because rotation speed did not differ between soccer-players and non-athletes this finding cannot be attributed to the mental rotation process itself but instead to differences in one of the following processes which are involved in a mental rotation task: the encoding process, the maintanence of readiness, or the motor process. The results are discussed against the background of the influence on longterm physical activity on mental rotation and the context of embodied cognition. PMID:23119073

ISOKINETIC KNEE MUSCLE STRENGTH PROFILE IN BRAZILIAN MALE SOCCER, FUTSAL, AND BEACH SOCCER PLAYERS: A CROSS-SECTIONAL STUDY

PubMed Central

Mascarin, Naryana C.; Vargas, Valentine Z.; Vancini, Rodrigo L.; Andrade, Marília S.

2017-01-01

Background Anterior cruciate ligament injury is higher in soccer athletes as compared to athletes of other sports. Risk factors for anterior cruciate ligament injury include low knee hamstring/quadriceps strength ratio and bilateral strength deficits. Purpose To investigate isokinetic thigh muscles strength, hamstring/quadriceps strength ratio, and bilateral strength comparisons in athletes who participate in professional soccer, futsal, and beach soccer. Study Design Cross-sectional study. Methods Brazilian professional soccer (n=70), futsal (n=30), and beach soccer (n=12) players were isokinetically assessed to examine strength of knee extensors and flexors at 60 degrees/second in concentric mode, to measure peak torque of dominant and non-dominant limbs. Results In the dominant limb, for extensors muscles, futsal players presented significantly lower peak torque values (223.9 ± 33.4 Nm) than soccer (250.9 ± 43.0 Nm; p=0.02) and beach soccer players (253.1 ± 32.4 Nm; p=0.03). Peak torque for extensor muscles in the non-dominant limb was significantly lower in futsal (224.0 ± 35.8 Nm) than in beach soccer players (256.8 ± 39.8 Nm; p=0.03). Hamstring/quadriceps strength ratio for dominant limbs for futsal (57.6 ± 10.1%), soccer (53.5 ± 8.8%), and beach soccer (56.3 ± 8.4%) players presented no significant differences between groups; however, the mean values were lower than recommended values found in the literature. There were no strength deficits for any of the evaluated groups when compared bilaterally. Conclusions Futsal athletes presented lower values for quadriceps strength than soccer and beach soccer athletes. Futsal, soccer, and beach soccer players presented no strength asymmetries, but they presented with strength imbalance in hamstring/quadriceps strength ratio. Level of Evidence 3 PMID:29234562

Strength and Jump Biomechanics of Elite and Recreational Female Youth Soccer Players

PubMed Central

Chrisman, Sara P.; O'Kane, John W.; Polissar, Nayak L.; Tencer, Allan F.; Mack, Christopher D.; Levy, Marni R.; Schiff, Melissa A.

2012-01-01

Context Most researchers investigating soccer injuries have studied elite athletes because they have greater athletic-exposure hours than other athletes, but most youth participate at the recreational level. If risk factors for injury vary by soccer level, then recommendations generated using research with elite youth soccer players might not generalize to recreational players. Objective To examine injury risk factors of strength and jump biomechanics by soccer level in female youth athletes and to determine whether research recommendations based on elite youth athletes could be generalized to recreational players. Design Cross-sectional study. Setting Seattle Youth Soccer Association. Patients or Other Participants Female soccer players (N = 92) aged 11 to 14 years were recruited from 4 randomly selected elite (n = 50; age = 12.5 years, 95% confidence interval [95% CI]) = 12.3, 12.8 years; height = 157.8 cm, 95% CI = 155.2, 160.3 cm; mass = 49.9 kg, 95% CI = 47.3, 52.6 kg) and 4 randomly selected recreational (n = 42; age = 13.2 years, 95% CI = 13.0, 13.5 years; height = 161.1 cm, 95% CI = 159.2, 163.1 cm; mass = 50.6 kg, 95% CI = 48.3, 53.0 kg) soccer teams. Main Outcome Measure(s) Players completed a questionnaire about demographics, history of previous injury, and soccer experience. Physical therapists used dynamometry to measure hip strength (abduction, adduction, extension, flexion) and knee strength (flexion, extension) and Sportsmetrics to measure vertical jump height and jump biomechanics. We compared all measurements by soccer level using linear regression to adjust for age and mass. Results Elite players were similar to recreational players in all measures of hip and knee strength, vertical jump height, and normalized knee separation (a valgus estimate generated using Sportsmetrics). Conclusions Female elite youth players and recreational players had similar lower extremity strength and jump biomechanics. This suggests that recommendations generated from

Are there any differences in power performance and morphological characteristics of Croatian adolescent soccer players according to the team position?

PubMed

Sporis, Goran; Vucetić, Vlatko; Jovanović, Mario; Milanović, Zoran; Rucević, Marijan; Vuleta, Dinko

2011-12-01

The aim of the study was to analyze differences in power performance and morphological characteristics of young Croatian soccer players with respect to their team positions and to establish correlations between the power performance variables. Anthropometric characteristics and jumping and sprint performances were analyzed for 45 soccer players (age 14-15; mean body height 175.4 +/- 6.61 cm; body weight 63.6 +/- 8.06 kg) according to their team positions (defender, midfielder, forward). Pearsons coefficient of correlation was used to determine the relationship between the power performance variables. There were no significant differences (p > 0.05) in the power performance of players according to their team position. The only significant differences between players were in some of the anthropometric characteristics, such as height and weight linear relationship was determined between almost all the power performance variables. Since the players in this study were very young and their sports careers have not reached their peak performance, it is possible that their nominal team positions may change during their soccer careers.

Premier League academy soccer players' experiences of competing in a tournament bio-banded for biological maturation.

PubMed

Cumming, Sean P; Brown, Daniel J; Mitchell, Siobhan; Bunce, James; Hunt, Dan; Hedges, Chris; Crane, Gregory; Gross, Aleks; Scott, Sam; Franklin, Ed; Breakspear, Dave; Dennison, Luke; White, Paul; Cain, Andrew; Eisenmann, Joey C; Malina, Robert M

2018-04-01

Individual differences in the growth and maturation have been shown to impact player performance and development in youth soccer. This study investigated Premier League academy players' experiences of participating in a tournament bio-banded for biological maturation. Players (N = 66) from four professional soccer clubs aged 11 and 14 years and between 85-90% of adult stature participated in a tournament. Players competed in three 11 vs 11 games on a full size pitch with 25-min halves. Sixteen players participated in four 15-min focus groups and were asked to describe their experiences of participating in the bio-banded tournament in comparison to age group competition. All players described their experience as positive and recommended the Premier League integrate bio-banding into the existing games programme. In comparison to age-group competitions, early maturing players described the bio-banded games more physically challenging, and found that they had to adapt their style of play placing a greater emphasis on technique and tactics. Late maturing players considered the games to be less physically challenging, yet appreciated the having more opportunity to use, develop and demonstrate their technical, physical, and psychological competencies. Bio-banding strategies appear to contribute positively towards the holistic development of young soccer players.

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.

MRI findings in soccer players with long-standing adductor-related groin pain and asymptomatic controls.

PubMed

Branci, Sonia; Thorborg, Kristian; Bech, Birthe Højlund; Boesen, Mikael; Nielsen, Michael Bachmann; Hölmich, Per

2015-05-01

Soccer players are commonly affected by long-standing adductor-related groin pain (ARGP), but the clinical significance of MRI findings in these athletes is largely unknown. Our aims were (1) to evaluate whether MRI findings are associated with long-standing ARGP in soccer players, (2) to assess MRI findings in asymptomatic soccer players and non-soccer playing controls. This cross-sectional study included 28 male soccer players with long-standing ARGP, 17 male asymptomatic soccer players and 20 male asymptomatic non-soccer playing athletes of matching age and athletic exposure. Participants underwent identical standardised and reliable clinical examination, and MRI scans (3 T) of the pelvis performed by a blinded observer. Images were consensus rated by three blinded radiologists according to a standardised MRI evaluation protocol. The associations between clinical adductor-related findings and pathological MRI findings were investigated with χ(2) statistics and OR. Central disc protrusion (p=0.027) and higher grades of pubic bone marrow oedema (BMO; p=0.027) were significantly more present in symptomatic players than asymptomatic players. However, up to 71% of asymptomatic soccer players displayed different positive MRI findings, and asymptomatic soccer players had significantly higher odds (OR ranging from 6.3 to 13.3) for BMO, adductor tendinopathy and degenerative changes than non-soccer players. ARGP in soccer players was associated with central disc protrusion and higher grades of pubic BMO. Moreover, positive MRI findings were significantly more frequent in soccer players compared with non-soccer players irrespective of symptoms, suggesting that these MRI changes may be associated with soccer play itself rather than clinical symptoms. 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.

Effects of vitamin C and exercise on lipid profile, platelet and erythrocyte indices in young soccer players.

PubMed

Karakilcik, A Z; Halat, R; Zerin, M; Celik, H; Nazligul, Y

2014-10-01

Exercise may increase production of reactive oxygen species (ROS) enhancing oxidative stress. Antioxidants can efficiently scavenge ROS before they initiate oxidative damage of biomolecules such as enzymes, nucleic acids, lipids and lipoproteins in the body. Vitamin C, an important antioxidant, may affect oxidative stress in living organism. Therefore, this study was carried out to investigate the effects of exercise and vitamin C on thiobarbituric acid-reactive substance (TBARS), lipid profile, erythrocyte and platelet indices in young soccer players. This investigation was carried out on twenty two male volunteer players in three groups. The first group was examined as a control. The second group was only exposed to exercise. The third group was exposed to exercise plus vitamin C (500 mg/day) administered per oral. The players were 23.50±0.59 year-old, 67.66±1.52 kg body weight and 1.74±0.03 m height. Blood samples were collected in vacutainer tubes for analysis of biochemical and hematological parameters. While the levels of high density lipoprotein-cholesterol (HDL-C) were significantly increased (P<0.05) with only exercise, the cholesterol and low density lipoprotein-cholesterol (LDL-C) were decreased (P<0.05 to P<0.01) with exercise and exercise plus vitamin C treatment. While TBARS levels were increased (P<0.05) with exercise training, it was decreased (P<0.05) with exercise plus vitamin C treatment. The platelet counts (PLT), mean platelet volume (MPV), plateletcrit (PCT) and red blood cell distribution width (RDW) were significantly decreased (P<0.05) with exercise plus vitamin C. There were significantly correlations (P<0.05 to P<0.01) between lipid values and erythrocyte and platelet indices. In light of these results, exercise may play a role in decreasing of LDL-C and in increasing of HDL-C. In addition, exercise plus vitamin C may diminish TBARS-levels and may affect the values of PLT, MPV, PCT and RDW in young soccer players.

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

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.

[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.

Physical Performance Comparison between Under 15 Elite and Sub-Elite Soccer Players

PubMed Central

Trecroci, Athos; Milanović, Zoran; Frontini, Matteo; Iaia, F. Marcello; Alberti, Giampietro

2018-01-01

Abstract The aim of this study was to compare the physical performance profile among young soccer players of different competitive levels. Two teams of elite (n = 22) and sub-elite (n = 22) soccer players at national (highly skilled) and regional (moderately skilled) level were recruited in the study. All participants were tested using a modified Illinois change of direction speed test, a T-drill with and without a ball, a countermovement jump, and a 10-m sprint. The analysis revealed significant differences in favor of elite players in sprint (d = 1.54, large) and vertical jump (d = 2.03, very large) outcomes, while no differences were observed in both modified Illinois change of direction speed (d = 0.16, trivial) and T-drill (d = 0.20, small) tests between the groups. The ability to change direction and speed with and without a ball was found not to be suitable enough to highlight the difference among youth players with moderate-to-high level of play. In conclusion, multi-testing approach based on task-related power should include vertical jump and sprint performance to delineate players of a higher level. PMID:29599873

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.

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.

Assessment of hydration status of elite young male soccer players with different methods and new approach method of substitute urine strip.

PubMed

Ersoy, Nesli; Ersoy, Gulgun; Kutlu, Mehmet

2016-01-01

The purpose of the study is to determine and compare the hydration status with different methods and determine fluid intake, dehydration percentages and sweat rate of 26 young male soccer players (15 ± 1.2 years) before an important competition. More specifically, the study aims at validating the urine strip and advising the players to use it as an easy and practical method. Measurements of urine analysis were taken from the urine sample of the participants before breakfast and conducted for 3 consecutive days before the competition. Hydration status was assessed through analysis of urine color, urine specific gravity (USG) (laboratory, strip, refractometry), and osmolality. The players' dehydration percentages and sweat ratio were calculated. The average values for all samples were 3 ± 1 for color, and 1.021 ± 4 g/cm(3) for USG (laboratory), and 1.021 ± 3 g/cm(3) for USG (strip), and 1.021 ± 4 for USG (refractometry), and 903 ± 133 mOsm/kg for osmolality. USG (strip) was highly correlated with USG (laboratory), USG (refractometry) (r = 0.8; P < 0.01) and osmolality (r = 0.7; P < 0.01), and moderately correlated with urine color (r = 0.4; P < 0.05). The mean dehydration percentage and sweat rate of the soccer players were observed as 0.5 % and 582.3 ± 232.0 mL/h, respectively. We found that youth soccer players are under a slight risk of dehydration under moderate weather conditions. As indicated by the research results, determination of hydration status of athletes must be taken into account more carefully under moderate and hot weather conditions. In addition, hydration methods were compatible with one another as measured in this study.

Symmetry of proprioceptive sense in female soccer players.

PubMed

Iwańska, Dagmara; Karczewska, Magdalena; Madej, Anna; Urbanik, Czesław

2015-01-01

The purpose of the study was to assess the symmetry of proprioceptive sense among female soccer players when trying to reproduce isometric knee extensions (right and left) and to analyze the impact of a given level of muscle force on proprioception. The study involved 12 soccer players aged 19.5 ± 2.65 years. Soccer players performed a control measurement of a maximum 3s (knee at the 90°) position in the joint. Subsequently, 70%, 50%, and 30% of the maximum voluntary contraction (MVC) were all calculated and then reproduced by each subject with feedback. Next, the players reproduced the predefined muscle contraction values in three sequences: A - 50%, 70%, 30%; B - 50%, 30%, 70%; C - 70%, 30%, 50% of MVC without visual control. In every sequence, the participants found obtaining the value of 30% of MVC the most difficult. The value they reproduced most accurately was 70% of MVC. Both trial II and trial III demonstrated that the symmetry index SI significantly differed from values considered acceptable (SIRa). In each successive sequence the largest asymmetry occurred while reproducing the lowest values of MVC (30%) (p < 0.05). High level of prioprioceptive sense is important to soccer players due to the extensive overload associated with dynamics stops or changes in direction while running. Special attention should be paid to develop skills in sensing force of varying levels. It was much harder to reproduce the predefined values if there was no feedback.

Acute effects of two different initial heart rates on testing the Repeated Sprint Ability in young soccer players.

PubMed

Ruscello, B; Briotti, G; Tozzo, N; Partipilo, F; Taraborelli, M; Zeppetella, A; Padulo, J; D'Ottavio, S

2015-10-01

The aim of this paper was to investigate the acute effects of two different initial heart rates intensities when testing the repeated sprint ability (RSA) performances in young soccer players. Since there are many kinds of pre-match warm-ups, we chose to take as an absolute indicator of internal load the heart rate reached at the end of two different warm-up protocols (60 vs. 90% HRmax) and to compare the respective RSA performances. The RSA tests were performed on fifteen male soccer players (age: 17.9±1.5 years) with two sets of ten shuttle-sprints (15+15 m) with a 1:3 exercise to rest ratio, in different days (randomized order) with different HR% (60 & 90% HRmax). In order to compare the different sprint performances a Fatigue Index (FI%) was computed, while the blood lactate concentrations (BLa-) were measured before and after testing, to compare metabolic demand. Significant differences among trials within each sets (P<0.01) were found. Differences between sets were also found, especially comparing the last five trials for each set (Factorial ANOVA; P<0.01), effect size values confirming the relevance of these differences. Although the BLa- after warm-up was higher (36%) between 90% vs. 60% HRmax, after the RSA test the differences were considerably low (7%). Based on physiological information's this methodological approach (testing with initial 90%HRmax) reflects more realistically the metabolic background in which a soccer player operates during a real match. This background may be partially reproduced by warming up protocols that, by duration and metabolic commitment, can reproduce conveniently the physiological conditions encountered in a real game (e.g. HRmax≈85-95%; BLa->4 mmol/L(-1)).

Soccer player recognition by pixel classification in a hybrid color space

NASA Astrophysics Data System (ADS)

Vandenbroucke, Nicolas; Macaire, Ludovic; Postaire, Jack-Gerard

1997-08-01

Soccer is a very popular sport all over the world, Coaches and sport commentators need accurate information about soccer games, especially about the players behavior. These information can be gathered by inspectors who watch the soccer match and report manually the actions of the players involved in the principal phases of the game. Generally, these inspectors focus their attention on the few players standing near the ball and don't report about the motion of all the other players. So it seems desirable to design a system which automatically tracks all the players in real- time. That's why we propose to automatically track each player through the successive color images of the sequences acquired by a fixed color camera. Each player which is present in the image, is modelized by an active contour model or snake. When, during the soccer match, a player is hidden by another, the snakes which track these two players merge. So, it becomes impossible to track the players, except if the snakes are interactively re-initialized. Fortunately, in most cases, the two players don't belong to the same team. That is why we present an algorithm which recognizes the teams of the players by pixels representing the soccer ground which must be withdrawn before considering the players themselves. To eliminate these pixels, the color characteristics of the ground are determined interactively. In a second step, dealing with windows containing only one player of one team, the color features which yield the best discrimination between the two teams are selected. Thanks to these color features, the pixels associated to the players of the two teams form two separated clusters into a color space. In fact, there are many color representation systems and it's interesting to evaluate the features which provide the best separation between the two classes of pixels according to the players soccer suit. Finally, the classification process for image segmentation is based on the three most

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.

Differences in game reading between selected and non-selected youth soccer players.

PubMed

Den Hartigh, Ruud J R; Van Der Steen, Steffie; Hakvoort, Bas; Frencken, Wouter G P; Lemmink, Koen A P M

2018-02-01

Applying an established theory of cognitive development-Skill Theory-the current study compares the game-reading skills of youth players selected for a soccer school of a professional soccer club (n = 49) and their non-selected peers (n = 38). Participants described the actions taking place in videos of soccer game plays, and their verbalisations were coded using Skill Theory. Compared to the non-selected players, the selected players generally demonstrated higher levels of complexity in their game-reading, and structured the information of game elements-primarily the player, teammate and field-at higher complexity levels. These results demonstrate how Skill Theory can be used to assess, and distinguish game-reading of youth players with different expertise, a skill important for soccer, but also for other sports.

Prediction of hamstring injury in professional soccer players by isokinetic measurements

PubMed Central

Dauty, Marc; Menu, Pierre; Fouasson-Chailloux, Alban; Ferréol, Sophie; Dubois, Charles

2016-01-01

Summary Objectives previous studies investigating the ability of isokinetic strength ratios to predict hamstring injuries in soccer players have reported conflicting results. Hypothesis to determine if isokinetic ratios are able to predict hamstring injury occurring during the season in professional soccer players. Study Design case-control study; Level of evidence: 3. Methods from 2001 to 2011, 350 isokinetic tests were performed in 136 professional soccer players at the beginning of the soccer season. Fifty-seven players suffered hamstring injury during the season that followed the isokinetic tests. These players were compared with the 79 uninjured players. The bilateral concentric ratio (hamstring-to-hamstring), ipsilateral concentric ratio (hamstring-to-quadriceps), and mixed ratio (eccentric/concentric hamstring-to-quadriceps) were studied. The predictive ability of each ratio was established based on the likelihood ratio and post-test probability. Results the mixed ratio (30 eccentric/240 concentric hamstring-to-quadriceps) <0.8, ipsilateral ratio (180 concentric hamstring-to-quadriceps) <0.47, and bilateral ratio (60 concentric hamstring-to-hamstring) <0.85 were the most predictive of hamstring injury. The ipsilateral ratio <0.47 allowed prediction of the severity of the hamstring injury, and was also influenced by the length of time since administration of the isokinetic tests. Conclusion isokinetic ratios are useful for predicting the likelihood of hamstring injury in professional soccer players during the competitive season. PMID:27331039

Heart Rate Variability Discriminates Competitive Levels in Professional Soccer Players.

PubMed

Proietti, Riccardo; di Fronso, Selenia; Pereira, Lucas A; Bortoli, Laura; Robazza, Claudio; Nakamura, Fabio Y; Bertollo, Maurizio

2017-06-01

Heart rate variability (HRV) has been increasingly used to monitor team sports athletes. Besides the traditional time domain indices (i.e., the SD of successive RR intervals [SDNN] and the root mean square difference of successive normal RR intervals [RMSSD]), recently the use of the stress score (SS), which is an inverse function of the SD2 index derived from the Poincaré plot, and the sympathetic/parasympathetic ratio (S/PS) to monitor soccer players has been proposed. However, the reliability of these new indices and the ability of HRV to differentiate between soccer competitive levels are unknown. The aim of this study was to analyze the reliability of the different HRV-derived indices in professional soccer players during the competitive period and to compare HRV of professional soccer players from 3 teams of distinct competitive levels (i.e., Italian Second Division [2D], European League [EL], and Champions League [CL]). Fifty-four male professional soccer players from 3 different teams of 2 European countries (Italy and Germany) participated in the study. The intraclass correlation coefficient values of the HRV indices varied from 0.78 (very large) to 0.90 (near perfect). The coefficient of variation (CV) values for RMSSD and SDNN were all <5.00%, although the CV for SS was 6.13% and for S/PS, it was 21.33%. Both the CL and EL groups, assumed to be internationally qualified, presented higher lnRMSSD and lnSDNN and lower lnSS and S/PS than the 2D. Therefore, the HRV can be considered reliable in professional soccer players and is able to differentiate between international- and national-level players.

Soccer and Sudden Cardiac Death in Young Competitive Athletes: A Review

PubMed Central

Higgins, John P.; Andino, Aldo

2013-01-01

Sudden cardiac death (SCD) in young competitive athletes (<35 years old) is a tragic event that has been brought to public attention in the past few decades. The incidence of SCD is reported to be 1-2/100,000 per year, with athletes at a 2.5 times higher risk. Soccer is the most popular sport in the world, played by people of all ages. However, unfortunately it is cardiovascular diseases such as hypertrophic cardiomyopathy and arrhythmogenic right ventricular cardiomyopathy that have subtly missed screening and claimed the lives of soccer stars such as Marc Vivien Foe and Antonio Puerta during live action on the field and on an internationally televised stage. This paper covers the physiological demands of soccer and the relationship between soccer and SCD. It also reviews the most common causes of SCD in young athletes, discusses the current guidelines in place by The Fédération Internationale de Football Association (FIFA) for screening among professional soccer players, and the precautions that have been put in place to prevent SCD on the field in professional soccer. PMID:26464886

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

Academic performance and self-regulatory skills in elite youth soccer players.

PubMed

Jonker, Laura; Elferink-Gemser, Marije T; Toering, Tynke T; Lyons, James; Visscher, Chris

2010-12-01

Although elite athletes have been reported to be high academic achievers, many elite soccer players struggle with a stereotype of being low academic achievers. The purpose of this study was to compare the academic level (pre-university or pre-vocational) and self-regulatory skills (planning, self-monitoring, evaluation, reflection, effort, and self-efficacy) of elite youth soccer players aged 12-16 years (n = 128) with those of 164 age-matched controls (typical students). The results demonstrate that the elite youth soccer players are more often enrolled in the pre-university academic system, which means that they are high academic achievers, compared with the typical student. The elite players also report an increased use of self-regulatory skills, in particular self-monitoring, evaluation, reflection, and effort. In addition, control students in the pre-university system had more highly developed self-regulatory skills than those in the pre-vocational system, whereas no difference was observed within the soccer population. This suggests that the relatively stronger self-regulatory skills reported by the elite youth soccer players may be essential for performance at the highest levels of sport competition and in academia.

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

Testosterone Concentration and Lower Limb Power Over an Entire Competitive Season in Elite Young Soccer Players.

PubMed

Arruda, Ademir F S; Aoki, Marcelo S; Freitas, Camila G; Spigolon, Leandro M P; Franciscon, Clovis; Moreira, Alexandre

2015-12-01

The aim of this study was to investigate salivary T changes and its relationship with power performance over a 1-year competitive season in elite under 15 (U15) and under 17 (U17) soccer players. Soccer players were recruited from 1 soccer club that has been participated in the main state and national leagues for these age groups. The soccer players were divided into 2 age categories (U15, n = 16 and U17, n = 23). A resting saliva sample was taken to determine T level, and power was assessed using the countermovement jump test with a bar of 30% of body mass on the athletes' shoulders on 3 occasions (T1: beginning of the competitive season, T2: end of the regular season, and T3: end of the playoffs). There was a decrease in T concentration at the end of the competitive season (T3) as compared with the beginning of the season (T1) for both age categories (p ≤ 0.05). Conversely, power performance parameters were increased for both age groups (U15: mean power and relative mean power and U17: peak power, mean power, relative peak power, and relative mean power; p ≤ 0.05). No significant correlation was identified between the relative changes in T concentration and power performance in both groups. The findings of this study suggest that T changes and power changes are not related.

Exercise Intensity and Technical Demands of Small-Sided Soccer Games for Under-12 and Under-14 Players: Effect of Area per Player.

PubMed

Martone, Domenico; Giacobbe, Moreno; Capobianco, Adriano; Imperlini, Esther; Mancini, Annamaria; Capasso, Mario; Buono, Pasqualina; Orrù, Stefania

2017-06-01

The aim of this study was to evaluate the effects of 6 different areas per player (AP) on exercise intensity (EI) measured during small-sided games (SSGs) and expressed as percentage of maximal heart rate (%MHR) and technical actions (TAs) involvement with the ball, crosses, headers, tackles, shots on goal, dribbling, passing, and target passing-in U-12 and U-14 soccer players during SSGs. Seventeen male U-12 soccer players (age 10.0 ± 0.5 years, body mass 39.3 ± 5.3 kg, and height 143.8 ± 4.6 cm) and 16 male U-14 soccer players (age 13.2 ± 0.3 years, body mass 46.6 ± 11.9 kg, and height 154.8 ± 8.5 cm) performed SSGs with different AP: 40, 50, 66.7, 90, 112.5, and 150 m. Our results indicate that at larger AP, the U-12 group's mean EI values were significantly higher than those at smaller AP (p ≤ 0.05); in addition, intergroup comparison showed that EI was higher in U-12 than that in U-14 players when AP of 112.5 and 150 m were considered (p ≤ 0.05). Technical action analysis evidenced that moving from smaller to larger AP, U-14 players adapted better to AP changes. In conclusion, these results suggest that AP influences differently EI and TAs in U-12 and U-14 players. Our results could be taken into account by conditioning coaches to better tailor the physiological and technical training in young players through the modulation of AP.

Return to sports after arthroscopic capsulolabral repair using knotless suture anchors for anterior shoulder instability in soccer players: minimum 5-year follow-up study.

PubMed

Alentorn-Geli, Eduard; Álvarez-Díaz, Pedro; Doblas, Jesús; Steinbacher, Gilbert; Seijas, Roberto; Ares, Oscar; Boffa, Juan José; Cuscó, Xavier; Cugat, Ramón

2016-02-01

To report the return to sports and recurrence rates in competitive soccer players after arthroscopic capsulolabral repair using knotless suture anchors at a minimum of 5 years of follow-up. All competitive soccer players with anterior glenohumeral instability treated by arthroscopic capsulolabral repair using knotless suture anchors between 2002 and 2009 were retrospectively identified through the medical records. Inclusion criteria were: no previous surgical treatment of the involved shoulder, absence of glenoid or tuberosity fractures, absence of large Hill-Sachs or glenoid bone defect, minimum follow-up of 5 years, instability during soccer practice or games, and failure of non-surgical treatment. The charts of included players were reviewed, and a phone call was performed in a cross-sectional manner to obtain information on: current soccer, return to soccer, recurrence of instability, shoulder function (Rowe score), and disability [Quick-Disability of the Arm, Shoulder, and Hand (DASH) score and Quick-DASH Sports/Performing Arts Module]. Fifty-seven young male soccer players were finally included with a median (range) follow-up of 8 (5-10) years. Forty-nine (86 %) of the soccer players were able to return to soccer and 36 of them (73 %) at the same pre-injury level. There were 6 (10.5 %) re-dislocations in the 57 players, all of them of traumatic origin produced during soccer and other unrelated activities. The main reasons to not return to soccer were: knee injuries (two players), changes in personal life (two players), and job-related (three players). None of the players quit playing soccer because of their shoulder instability injury. The median (range) Rowe score, Quick-DASH score, and Quick-DASH sports score were 80 (25-100), 2.3 (0-12.5), and 0 (0-18.8), respectively. Competitive soccer players undergoing arthroscopic capsulolabral repair with knotless suture anchors for shoulder instability without significant bone loss demonstrate excellent return to

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.

Iron deficiency and anemia: a common problem in female elite soccer players.

PubMed

Landahl, Göran; Adolfsson, Peter; Börjesson, Mats; Mannheimer, Clas; Rödjer, Stig

2005-12-01

The objective of the study was to determine the prevalence of iron deficiency and iron deficiency anemia among elite women soccer players. Hemoglobin, serum iron, serum total iron binding capacity, and ferritin were determined in 28 female soccer players called up for the national team. Of the investigated female soccer players, 57% had iron deficiency and 29% iron deficiency anemia 6 months before the FIFA Women's World Cup. It is concluded that iron deficiency and iron deficiency anemia is common in female soccer players at the top international level. Some might suffer from relative anemia and measurement of hemoglobin alone is not sufficient to reveal relative anemia. Regular monitoring of hemoglobin concentration and iron status is necessary to institute iron supplementation when indicated.

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

Differences in Soccer Kick Kinematics between Blind Players and Controls

ERIC Educational Resources Information Center

Giagazoglou, Paraskevi; Katis, Athanasios; Kellis, Eleftherios; Natsikas, Christos

2011-01-01

The purpose of the current study was to examine the kinematic differences during instep soccer kicks between players who were blind and sighted controls. Eleven male soccer players who were blind and nine male sighted performed instep kicks under static and dynamic conditions. The results indicated significantly higher (p less than 0.05) ball…

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.

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

Static stretching does not enhance recovery in elite youth soccer players

PubMed Central

Pooley, Sam; Spendiff, Owen; Allen, Matt; Moir, Hannah J

2017-01-01

Background Static stretching (SS) is a recovery intervention used for the reduction of muscle soreness postexercise. The effects of SS on elite young footballers have received little attention, and therefore the aim of this study was to assess the effects of SS on muscle recovery following competitive soccer matches in elite young footballers. Methods Ten male participants (16±1 years) were recruited from an English Premier League professional soccer academy. Using a controlled crossover design, participants followed one of two recovery interventions (SS or passive recovery (PR)) immediately following completion of competitive soccer matches. Muscle oedema, creatine kinase (CK), countermovement jump with arms (CMJA) performance and perceived muscle soreness were assessed before, immediately after and 48 hours postmatch. Results Competitive soccer matches significantly induced muscle damage, with time intervals of perceived soreness and CK showing significant increases (p<0.05), and CMJA showing significant decreases between prematch, postmatch and 48 hours postmatch for both SS and PR (p<0.05). Comparisons of the absolute effects of SS with PR only revealed significant decreases for CK 48 hours postmatch (p<0.05) as a result of SS intervention. Conclusion The current study demonstrated competitive soccer matches induced muscle damage, which may have detrimental effects on future performance within 24–48 hours postmatch. Furthermore, there was limited evidence to suggest SS would assist in the reduction of muscle soreness postexercise. Therefore, it can be argued that SS is not a beneficial recovery option for elite youth soccer players. PMID:28761702

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.

Pre-season dietary intake of professional soccer players.

PubMed

Raizel, Raquel; da Mata Godois, Allan; Coqueiro, Audrey Yule; Voltarelli, Fabrício Azevedo; Fett, Carlos Alexandre; Tirapegui, Julio; de Paula Ravagnani, Fabricio Cesar; de Faria Coelho-Ravagnani, Christianne

2017-12-01

Despite the well-documented importance of nutrition in optimizing performance and health, the dietary intake of soccer players has attracted little attention. We aimed to assess the pre-season dietary intake of professional soccer players and its adequacy in macro and micronutrients. The pre-season dietary intake of 19 male athletes was assessed using a semi-structured 3-day food record. To determine dietary adequacy and excess, energy and macronutrient intake were compared with the Brazilian dietary reference values for athletes, and micronutrients were compared with the Estimated Average Requirement - EAR (minimum recommendation) and Tolerable Upper Intake Level - UL (maximum recommendation). Mean daily energy intake (40.74±12.81 kcal/kg) was adequate. However, there was a low carbohydrate intake (5.44±1.86 g/kg/day) and a high amount of protein and fat (1.91±0.75 and 1.27±0.50 g/kg/day, respectively). Sodium intake (3141.77±939.76 mg/day) was higher than UL (2300 mg/day), while the majority of players showed daily intake of vitamin A (74%), vitamin D (100%), folate (58%), calcium and magnesium (68%) below the EAR (625, 10 and 320 µg/day, 800 and 330 mg/day, respectively). The dietary intake of professional soccer players was adequate in energy, but inadequate in macro and micronutrients, which suggests the need to improve nutritional practices to sustain the physical demands of soccer during pre-season.

Monitoring performance, pituitary-adrenal hormones and mood profiles: how to diagnose non-functional over-reaching in male elite junior soccer players.

PubMed

Schmikli, Sándor L; de Vries, Wouter R; Brink, Michel S; Backx, Frank Jg

2012-11-01

To verify if in male elite junior soccer players a minimum 1-month performance decrease is accompanied by a mood profile and hormone levels typical of non-functional over-reaching (NFOR). A prospective case-control study using a monthly performance monitor with a standardised field test to detect the performance changes. Players with a performance decrease lasting at least 1 month were compared with control players without a performance decrease on mood scores and pre-exercise and postexercise levels of stress hormones. Sporting field and sports medical laboratory. Ninety-four young elite soccer players were monitored during the 2006-2008 seasons. Twenty-one players were invited to the laboratory, seven of whom showed a significant performance decrease. Performance change over time, scores on the profile of mood states and premaximal and postmaximal exercise serum levels of adrenocorticotropic hormone (ACTH), growth hormone (GH) and cortisol. Players with a performance decrease showed psychological and hormonal changes typical of the non-functional state of over-reaching. Scores were higher on depression and anger, whereas the resting GH levels and ACTH levels after maximal exercise were reduced. ACTH and GH were capable of classifying all but one player correctly as either NFOR or control. Performance-related criteria in field tests are capable of identifying players with worsened mood and adaptations of the endocrine system that fit the definition of NFOR. Performance, mood and hormone levels may therefore be considered as valid instruments to diagnose NFOR in young elite soccer players.

Repeated change-of-direction test for collegiate male soccer players.

PubMed

Mizuguchi, S; Gray, H; Calabrese, L S; Haff, G G; Sands, W A; Ramsey, M W; Cardinale, M; Stone, M H

2014-08-01

The aim of the study was to investigate the applicability of a repeated change-of-direction (RCoD) test for NCAA Division-I male soccer players. The RCoD test consisted of 5 diagonal direction changes per repetition with a soccer ball to be struck at the end. Each player performed 15 repetitions with approximately 10 seconds to jog back between repetitions. Data were collected in two sessions. In the first session, 13 players were examined for heart rate responses and blood lactate concentrations. In the second session, 22 players were examined for the test's ability to discriminate the primary from secondary players (78.0±16.1 and 10.4±13.3 minutes per match, respectively). Heart rate data were available only from 9 players due to artifacts. The peak heart rate (200.2±6.6 beats∙min-1: 99.9±3.0% maximum) and blood lactate concentration (14.8±2.4 mmol∙L-1 immediately after) resulted in approximately 3.5 and 6.4-fold increases from the resting values, respectively. These values appear comparable to those during intense periods of soccer matches. In addition, the average repetition time of the test was found to discriminate the primary (4.85±0.23 s) from the secondary players (5.10±0.24 s) (P=0.02). The RCoD test appears to induce physiological responses similar to intense periods of soccer matches with respect to heart rate and blood lactate concentration. Players with better average repetition times tend to be those who play major minutes.

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.

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

Position-Specific Acceleration and Deceleration Profiles in Elite Youth and Senior Soccer Players.

PubMed

Vigh-Larsen, Jeppe F; Dalgas, Ulrik; Andersen, Thomas B

2018-04-01

Vigh-Larsen, JF, Dalgas, U, and Andersen, TB. Position-specific acceleration and deceleration profiles in elite youth and senior soccer players. J Strength Cond Res 32(4): 1114-1122, 2018-The purpose of the study was to characterize and compare the position-specific activity profiles of young and senior elite soccer players with special emphasis put on accelerations and decelerations. Eight professional senior matches were tracked using the ZXY tracking system and analyzed for the number of accelerations and decelerations and running distances within different speed zones. Likewise, 4 U19 and 5 U17 matches were analyzed for comparison between youth and senior players. In senior players, the total distance (TD) was 10,776 ± 107 m with 668 ± 28 and 143 ± 10 m being high-intensity running (HIR) and sprinting, respectively. Number of accelerations and decelerations were 81 ± 2 and 84 ± 3, respectively, with central defenders performing the lowest and wide players the highest number. Declines were found between first and second halves for accelerations and decelerations (11 ± 3%), HIR (6 ± 4%), and TD (5 ± 1%), whereas sprinting distance did not differ. U19 players performed a higher number of accelerations, decelerations, and TD compared with senior players. In conclusion, differences in the number and distribution of accelerations and decelerations appeared between player positions, which is of importance when monitoring training and match loads and when prescribing specific training exercises. Furthermore, youth players performed as much high-intensity activities as senior players, indicating that this is not a discriminating physiological parameter between these players.

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

Leg Preference and Interlateral Asymmetry of Balance Stability in Soccer Players

ERIC Educational Resources Information Center

Teixeira, Luis Augusto; de Oliveira, Dalton Lustosa; Romano, Rosangela Guimaraes; Correa, Sonia Cavalcanti

2011-01-01

To examine the effect of long lasting practice on pedal behavior in sport, we compared experienced adult soccer players and nonsoccer players on leg preference in motor tasks requiring general mobilization, soccer related mobilization, and body balance stabilization. We also evaluated performance asymmetry between the right and left legs in static…

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

Analysis of the intraseasonal stability of field test performances in young academy soccer players.

PubMed

Francioni, Fabio Massimo; Figueiredo, António José; Terribili, Marco; Tessitore, Antonio

2016-01-01

This study aimed to observe the intraseasonal stability of anthropometric, technical and functional test results in academy soccer players of different age categories. In total, 103 participants (age range: 7.7-13.4 years) by 5 age categories of the same academy were recruited for this study. Players were submitted to a field-test battery comprising 3 anthropometric measurements (body mass, stature and body mass index), 6 soccer technical tests (to assess the ability of ball control, ball control with the head, pass accuracy, shooting accuracy, dribbling and dribbling with pass) and 3 functional tests (countermovement jump with the hands on the hip, countermovement jump with free hands and 15-m linear sprint) that was administered in 4 test sessions during the same season. Though anthropometric results showed a clear increment in each age category across the season, the fluctuation of technical test results depended on age category and test session. Moreover, a significant increase in the results of functional tests was observed in most of the age categories, in particular, for the assessment of lower power limb. In conclusion, collecting repeated intraseason measurements permits the identification of players' fluctuations of performance across the season and allows coaches to make frequent adjustments of their programmes.

The relationship between the yo-yo tests, anaerobic performance and aerobic performance in young soccer players.

PubMed

Karakoç, Barış; Akalan, Cengiz; Alemdaroğlu, Utku; Arslan, Erşan

2012-12-01

The purposes of this study were to determine the relationship between performance in the Yo-Yo intermittent recovery test level 1 (YIRT1), the Yo-Yo intermittent recovery test level 2 (YIRT2) and the Yo-Yo endurance test (continuous) (YET) with maximal oxygen uptake (VO2max) and Wingate anaerobic performance (WaNT) test results in young soccer players (age 15.00 ± 0.0 years, body height 176.3 ± 4.2 cm and body mass 68.1 ± 3.6 kg). An ergospirometry device was used during the treadmill test (TRT) to determine VO2max. At the end of the study, significant differences were found between the Yo-Yo tests and TRT in terms of HRmax (TRT = 195,92, YIRT1 = 197,83, YIRT2 = 198,5 YET = 198) (p > 0.05). While there were moderate correlations between VO2max and YIRT 1-2 performances (respectively, r = 0.56, r = 0.53), there was only a weak relationship between VO2max and YET performance (r = 0.43) (distance covered). There were also moderate significant negative correlations between performance in the YIRT2 and peak power measured in the WaNT (r = -0.55), although there were no significant correlations between performance in the three tests and average power. A moderate negative correlation was found between performance in the YIRT2 and Fatigue index (FI) (r = -0,66). In conclusion, the YIRT2 may be a more suitable field test for determining both aerobic and anaerobic performance in soccer players.

The Relationship Between the Yo-Yo Tests, Anaerobic Performance and Aerobic Performance in Young Soccer Players

PubMed Central

Karakoç, Barış; Akalan, Cengiz; Alemdaroğlu, Utku; Arslan, Erşan

2012-01-01

The purposes of this study were to determine the relationship between performance in the Yo-Yo intermittent recovery test level 1 (YIRT1), the Yo-Yo intermittent recovery test level 2 (YIRT2) and the Yo-Yo endurance test (continuous) (YET) with maximal oxygen uptake (VO2max) and Wingate anaerobic performance (WaNT) test results in young soccer players (age 15.00 ± 0.0 years, body height 176.3 ± 4.2 cm and body mass 68.1 ± 3.6 kg). An ergospirometry device was used during the treadmill test (TRT) to determine VO2max. At the end of the study, significant differences were found between the Yo-Yo tests and TRT in terms of HRmax (TRT = 195,92, YIRT1 = 197,83, YIRT2 = 198,5 YET = 198) (p > 0.05). While there were moderate correlations between VO2max and YIRT 1–2 performances (respectively, r = 0.56, r = 0.53), there was only a weak relationship between VO2max and YET performance (r = 0.43) (distance covered). There were also moderate significant negative correlations between performance in the YIRT2 and peak power measured in the WaNT (r = −0.55), although there were no significant correlations between performance in the three tests and average power. A moderate negative correlation was found between performance in the YIRT2 and Fatigue index (FI) (r = −0,66). In conclusion, the YIRT2 may be a more suitable field test for determining both aerobic and anaerobic performance in soccer players. PMID:23486008

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.

Altered Neurochemistry in Former Professional Soccer Players without a History of Concussion

PubMed Central

Lin, Alexander P.; Muehlmann, Marc; Merugumala, Sai; Liao, Huijun; Starr, Tyler; Kaufmann, David; Mayinger, Michael; Steffinger, Denise; Fisch, Barbara; Karch, Susanne; Heinen, Florian; Ertl-Wagner, Birgit; Reiser, Maximilian; Stern, Robert A.; Zafonte, Ross; Shenton, Martha E.

2015-01-01

Abstract Soccer is played by more than 250 million people worldwide. Repeatedly heading the ball may place soccer players at high risk for repetitive subconcussive head impacts (RSHI). This study evaluates the long-term effects of RSHI on neurochemistry in athletes without a history of clinically diagnosed concussion, but with a high exposure to RSHI. Eleven former professional soccer players (mean age 52.0±6.8 years) and a comparison cohort of 14 age- and gender-matched, former non-contact sport athletes (mean age 46.9±7.9 years) underwent 3T magnetic resonance spectroscopy (MRS) and neurocognitive evaluation. In the soccer players a significant increase was observed in both choline (Cho), a membrane marker, and myo-inositol (ml), a marker of glial activation, compared with control athletes. Additionally, ml and glutathione (GSH) were significantly correlated with lifetime estimate of RSHI within the soccer group. There was no significant difference in neurocognitive tests between groups. Results of this study suggest an association between RSHI in soccer players and MRS markers of neuroinflammation, suggesting that even subconcussive head impacts affect the neurochemistry of the brain and may precede neurocognitive changes. Future studies will need to determine the role of neuroinflammation in RSHI and the effect on neurocognitive function. PMID:25843317

Altered Neurochemistry in Former Professional Soccer Players without a History of Concussion.

PubMed

Koerte, Inga K; Lin, Alexander P; Muehlmann, Marc; Merugumala, Sai; Liao, Huijun; Starr, Tyler; Kaufmann, David; Mayinger, Michael; Steffinger, Denise; Fisch, Barbara; Karch, Susanne; Heinen, Florian; Ertl-Wagner, Birgit; Reiser, Maximilian; Stern, Robert A; Zafonte, Ross; Shenton, Martha E

2015-09-01

Soccer is played by more than 250 million people worldwide. Repeatedly heading the ball may place soccer players at high risk for repetitive subconcussive head impacts (RSHI). This study evaluates the long-term effects of RSHI on neurochemistry in athletes without a history of clinically diagnosed concussion, but with a high exposure to RSHI. Eleven former professional soccer players (mean age 52.0±6.8 years) and a comparison cohort of 14 age- and gender-matched, former non-contact sport athletes (mean age 46.9±7.9 years) underwent 3T magnetic resonance spectroscopy (MRS) and neurocognitive evaluation. In the soccer players a significant increase was observed in both choline (Cho), a membrane marker, and myo-inositol (ml), a marker of glial activation, compared with control athletes. Additionally, ml and glutathione (GSH) were significantly correlated with lifetime estimate of RSHI within the soccer group. There was no significant difference in neurocognitive tests between groups. Results of this study suggest an association between RSHI in soccer players and MRS markers of neuroinflammation, suggesting that even subconcussive head impacts affect the neurochemistry of the brain and may precede neurocognitive changes. Future studies will need to determine the role of neuroinflammation in RSHI and the effect on neurocognitive function.

Chronic spinal cord injury in the cervical spine of a young soccer player.

PubMed

Kato, Yoshihiko; Koga, Michiaki; Taguchi, Toshihiko

2010-05-12

A 17-year-old male soccer player presented with numbness in the upper- and lower-left extremities of 6 months' duration. He had no apparent history of trauma but experienced neck pain during heading of the ball 5 years prior. A high-signal intensity area was seen on T2-weighted magnetic resonance imaging (MRI) of the cervical spine. No muscle weakness was observed. Hypoesthesia was observed in bilateral forearms, hands, and extremities below the inguinal region. Plain radiographs in the neutral position showed local kyphosis at C3/4. A small protrusion of the C3/4 disk was observed on T1-weighted MRI. A high-signal area in the spinal cord at the C3/4 level was observed on T2-weighted MRI, but this was not enhanced by gadolinium. Multiple sclerosis, intramedullary spinal cord tumor, sarcoidosis and malignant lymphoma, and spinal cord injury were all considered in the differential diagnosis. However, in view of the clinical, laboratory, and radiological investigations, we concluded that repeated impacts to the neck caused by heading of the ball during soccer induced a chronic, minor spinal cord injury. This contributed to the high-signal intensity change of the spinal cord in T2-weighted MRI. The present case demonstrates that repeated impact may cause chronic spinal cord injury. Soccer, American football, or rugby players presenting with neck or extremity symptoms should not be overlooked for the possibility of latent spinal cord injury, as this could present later development of more severe or unrecoverable spinal cord injuries. Copyright 2010, SLACK Incorporated.

Treatment and evolution of grade III acromioclavicular dislocations in soccer players.

PubMed

Pereira-Graterol, Ernesto; Álvarez-Díaz, Pedro; Seijas, Roberto; Ares, Oscar; Cuscó, Xavier; Cugat, Ramón

2013-07-01

To evaluate postoperative functional results in soccer players diagnosed with acute grade III acromioclavicular dislocation, stabilized with clavicular hook plate. Between 2006 and 2010, 11 soccer players were diagnosed with acute acromioclavicular dislocation. Mean age was 22.9 years. The clavicular hook plate was used for stabilization. The follow-up was 4 years (2-6 years). Constant score showed 82 % excellent results and 18 % good functional results. Average pain measured with VAS was 1.8 (±0.59) mm out of 10. We did not report any complication within the process. Use of the clavicular hook plate is considered adequate for the treatment of acute acromioclavicular dislocation in soccer players, allowing a quick return to sports. Retrospective case series, Level IV.

Locomotor performance in highly-trained young soccer players: does body size always matter?

PubMed

Buchheit, M; Mendez-Villanueva, A; Mayer, N; Jullien, H; Marles, A; Bosquet, L; Maille, P; Morin, J-B; Cazorla, G; Lambert, P

2014-06-01

To examine the effects of body size on locomotor performance, 807 15-year-old French and 64 Qatari soccer players participated in the present study. They performed a 40-m sprint and an incremental running test to assess maximal sprinting (MSS) and aerobic speeds, respectively. French players were advanced in maturity, taller, heavier, faster and fitter than their Qatari counterparts (e.g., Cohen's d=+1.3 and + 0.5 for body mass and MSS). However, when adjusted for body mass (BM), Qatari players had possibly greater MSS than French players (d=+0.2). A relative age effect was observed within both countries, with the players born in the first quarter of the year being taller, heavier and faster that those born during the fourth quarter (e.g., d=+0.2 for MSS in French players). When directly adjusted for BM, these MSS differences remained (d=+0.2). Finally, in both countries, players selected in National teams were taller, heavier, faster and fitter than their non-selected counterparts (e.g., d=+0.6 for MSS in French players), even after adjustments for body size (d=+0.5). Differences in locomotor performances between players with different phenotypes are likely mediated by differences in body size. However, when considering more homogeneous player groups, body dimensions are unlikely to substantially explain the superior locomotor performances of older and/or international players. © Georg Thieme Verlag KG Stuttgart · New York.

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.

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

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

Patellar tendon properties distinguish elite from non-elite soccer players and are related to peak horizontal but not vertical power.

PubMed

Murtagh, Conall F; Stubbs, Michael; Vanrenterghem, Jos; O'Boyle, Andrew; Morgans, Ryland; Drust, Barry; Erskine, Robert M

2018-06-02

To investigate potential differences in patellar tendon properties between elite and non-elite soccer players, and to establish whether tendon properties were related to power assessed during unilateral jumps performed in different directions. Elite (n = 16; age 18.1 ± 1.0 years) and non-elite (n = 13; age 22.3 ± 2.7 years) soccer players performed vertical, horizontal-forward and medial unilateral countermovement jumps (CMJs) on a force plate. Patellar tendon (PT) cross-sectional area, elongation, strain, stiffness, and Young's modulus (measured at the highest common force interval) were assessed with ultrasonography and isokinetic dynamometry. Elite demonstrated greater PT elongation (6.83 ± 1.87 vs. 4.92 ± 1.88 mm, P = 0.011) and strain (11.73 ± 3.25 vs. 8.38 ± 3.06%, P = 0.009) than non-elite soccer players. Projectile range and peak horizontal power during horizontal-forward CMJ correlated positively with tendon elongation (r = 0.657 and 0.693, P < 0.001) but inversely with Young's modulus (r = - 0.376 and - 0.402; P = 0.044 and 0.031). Peak medial power during medial CMJ correlated positively with tendon elongation (r = 0.658, P < 0.001) but inversely with tendon stiffness (r = - 0.368, P = 0.050). Not only does a more compliant patellar tendon appear to be an indicator of elite soccer playing status but it may also facilitate unilateral horizontal-forward and medial, but not vertical CMJ performance. These findings should be considered when prescribing talent selection and development protocols related to direction-specific power in elite soccer players.

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.

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.

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.

Eccentric and Isometric Hip Adduction Strength in Male Soccer Players With and Without Adductor-Related Groin Pain

PubMed Central

Thorborg, Kristian; Branci, Sonia; Nielsen, Martin Peter; Tang, Lars; Nielsen, Michael Bachmann; Hölmich, Per

2014-01-01

Background: Adductor-related pain is the most common clinical finding in soccer players with groin pain and can be a long-standing problem affecting physical function and performance. Hip adductor weakness has been suggested to be associated with this clinical entity, although it has never been investigated. Purpose: To investigate whether isometric and eccentric hip strength are decreased in soccer players with adductor-related groin pain compared with asymptomatic soccer controls. The hypothesis was that players with adductor-related groin pain would have lower isometric and eccentric hip adduction strength than players without adductor-related groin pain. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Male elite and subelite players from 40 teams were contacted. In total, 28 soccer players with adductor-related groin pain and 16 soccer players without adductor-related groin pain (asymptomatic controls) were included in the study. In primary analysis, the dominant legs of 21 soccer players with adductor-related groin pain (≥4 weeks duration) were compared with the dominant legs of 16 asymptomatic controls using a cross-sectional design. The mean age of the symptomatic players was 24.5 ± 2.5 years, and the mean age of the asymptomatic controls was 22.9 ± 2.4 years. Isometric hip strength (adduction, abduction, and flexion) and eccentric hip strength (adduction) were assessed with a handheld dynamometer using reliable test procedures and a blinded assessor. Results: Eccentric hip adduction strength was lower in soccer players with adductor-related groin pain in the dominant leg (n = 21) compared with asymptomatic controls (n = 16), namely 2.47 ± 0.49 versus 3.12 ± 0.43 N·m/kg, respectively (P < .001). No other hip strength differences were observed between symptomatic players and asymptomatic controls for the dominant leg (P = .35-.84). Conclusion: Large eccentric hip adduction strength deficits were found in soccer players with adductor

Effects of age and spa treatment on match running performance over two consecutive games in highly trained young soccer players.

PubMed

Buchheit, Martin; Horobeanu, Cosmin; Mendez-Villanueva, Alberto; Simpson, Ben M; Bourdon, Pitre C

2011-03-01

The aim of this study was to examine the effect of age and spa treatment (i.e. combined sauna, cold water immersion, and jacuzzi) on match running performance over two consecutive matches in highly trained young soccer players. Fifteen pre- (age 12.8 ± 0.6 years) and 13 post- (15.9 ± 1 y) peak height velocity (PHV) players played two matches (Matches 1 and 2) within 48 h against the same opposition, with no specific between-match recovery intervention (control). Five post-PHV players also completed another set of two consecutive matches, with spa treatment implemented after the first match. Match running performance was assessed using a global positioning system with very-high-intensity running (> 16.1-19.0 km · h(-1)), sprinting distance (>19 km · h(-1)), and peak match speed determined. Match 2 very-high-intensity running was "possibly" impaired in post-PHV players (-9 ± 33%; ± 90% confidence limits), whereas it was "very likely" improved for the pre-PHV players (+27 ± 22%). The spa treatment had a beneficial impact on Match 2 running performance, with a "likely" rating for sprinting distance (+30 ± 67%) and "almost certain" for peak match speed (+6.4 ± 3%). The results suggest that spa treatment is an effective recovery intervention for post-PHV players, while its value in pre-PHV players is questionable.

The application of soccer performance testing protocols to the non-elite player.

PubMed

Siegler, J; Robergs, R; Weingart, H

2006-03-01

The application of performance testing for the evaluation of non-elite soccer players has received little attention. The purpose of this investigation was to use tests developed for elite soccer players to evaluate performance in non-elite soccer players and compare performance test results between elite (literature) and non-elite (data) players. Thirteen male soccer players volunteered to participate. The tests included a treadmill VO2max test, 20 m sprint, vertical jump (VJ), 30 s Wingate cycle ergometer test, the Loughborough Intermittent Shuttle Test (LIST), and 2 20-m multi-stage shuttle runs to exhaustion (fatigue test). Actual VO2max (absolute and relative) scores were correlated with the estimated VO2max scores (fatigue test), 20 m sprint, VJ, and 30 s Wingate using a Pearson's product-moment correlation. A paired t-test was conducted on the fatigue test trials. Non-significant relationships were observed between actual VO2max scores and estimated VO2max from the fatigue test (absolute and relative terms). Non-significant relationships were also observed between peak and average power output (Wingate), 20 m sprint, and VJ. Mean heart rates (HRs) throughout the LIST was 165+/-7 bpm, which represented 88% of HRmax. The results of this study demonstrate that to elicit physiological differences between elite and non-elite players, assessment must include both an aerobic and anaerobic component.

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…

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

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

ARE THERE DIFFERENCES IN STRENGTH TESTS USING ISOKINETIC DYNAMOMETRY BETWEEN FIELD AND INDOOR PROFESSIONAL SOCCER PLAYERS?

PubMed Central

de Aguiar Leonardi, Adriano Barros; Martinelli, Mauro Olivio; Junior, Aires Duarte

2015-01-01

Objective: The objective of this study was to conduct a comparative analysis on isokinetic strength assessments between field and indoor male professional soccer players and correlate the findings with the higher levels of injury risk described in the literature. Methods: We analyzed 16 field soccer players and 15 indoor soccer players. All these professionals were male. Isokinetic muscle strength assessments were made on their knees. Results: The mean weight was 81.81 kg for field soccer and 80.33 kg for indoor soccer. The right and left peak extensor torque left and right for field soccer and indoor soccer were, respectively, 302.50 and 313.31 Nm and 265.20 and 279.80 Nm, and for flexors, 178 and 184.88 Nm and 158.27 and 154 Nm. The peak torque rates according to body weight for the left and right extensors for field soccer and indoor soccer were, respectively, 3.84 and 3.7 Nm/kg and 3.32 and 3.52 Nm/kg, and for flexors, 2.17 and 2.26 Nm/kg and 1.98 and 1.93 Nm/kg. The balance relationships between flexors and extensors on the right and left sides for field soccer and indoor soccer were, respectively, 59.81 and 59.44% and 60.47% and 54.80%. The relationships for extensors between the right and left sides for field soccer and indoor soccer were, respectively, 11.44 and 9.20%, and for the flexors, 7.31 and 8.80%. Conclusions: In accordance with international parameters, comparative analysis on isokinetic strength assessments between field and indoor male professional soccer players before the season showed that there was muscle balance and low probability of injury. There were no statistically significant differences in the parameters analyzed between the players of the two types of soccer. PMID:27042649

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

Neuromuscular Risk Factors for Knee and Ankle Ligament Injuries in Male Youth Soccer Players

PubMed Central

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

2017-01-01

Injuries reported in male youth soccer players most commonly occur in the lower extremities, and include a high proportion of ligament sprains at the ankle and knee with a lower proportion of overuse injuries. There is currently a paucity of available literature that examines age- and sex-specific injury risk factors for such injuries within youth soccer players. Epidemiological data have reported movements that lead to non-contact ligament injury include running, twisting and turning, over-reaching and landing. Altered neuromuscular control during these actions has been suggested as a key mechanism in females and adult populations; however, data available in male soccer players is sparse. The focus of this article is to review the available literature and elucidate prevalent risk factors pertaining to male youth soccer players which may contribute to their relative risk of injury. PMID:26856339

Neuromuscular Risk Factors for Knee and Ankle Ligament Injuries in Male Youth Soccer Players.

PubMed

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

2016-08-01

Injuries reported in male youth soccer players most commonly occur in the lower extremities, and include a high proportion of ligament sprains at the ankle and knee with a lower proportion of overuse injuries. There is currently a paucity of available literature that examines age- and sex-specific injury risk factors for such injuries within youth soccer players. Epidemiological data have reported movements that lead to non-contact ligament injury include running, twisting and turning, over-reaching and landing. Altered neuromuscular control during these actions has been suggested as a key mechanism in females and adult populations; however, data available in male soccer players is sparse. The focus of this article is to review the available literature and elucidate prevalent risk factors pertaining to male youth soccer players which may contribute to their relative risk of injury.

Soccer players' fitting perception of different upper boot materials.

PubMed

Olaso Melis, J C; Priego Quesada, J I; Lucas-Cuevas, A G; González García, J C; Puigcerver Palau, S

2016-07-01

The present study assessed the influence of upper boot materials on fitting perception. Twenty players tested three soccer boots only differing in the upper boot material (natural calf leather, natural kangaroo leather and synthetic leather). Players reported fitting perception and preference on specific foot areas using a perceived fitting scale. Ratings were averaged for every foot area. Repeated measures ANOVA was used to analyze the differences between boots. The kangaroo leather boots were perceived tighter and closer to the preferred fitting in general fitting, metatarsals area and instep area. The synthetic leather boots were perceived as the loosest and as the most distant boot from the preferred fitting in medial front area and instep area. In conclusion, the type of upper boot material influences the fitting perception of soccer players. The kangaroo leather was the material whose fitting was perceived closest to the players fitting preference. Copyright © 2016 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Gaze Control in One Versus One Defensive Situations in Soccer Players With Various Levels of Expertise.

PubMed

Krzepota, Justyna; Stępiński, Miłosz; Zwierko, Teresa

2016-12-01

Experienced and less experienced soccer players were compared in terms of their gaze behavior (number of fixations, fixation duration, number of fixation regions, and distribution of fixations across specific regions) during frontal 1 vs. 1 defensive situations. Twenty-four men (eight experienced soccer players, eight less experienced players and eight non-players) watched 20 video clips. Gaze behavior was registered with an Eye Tracking System. The video scenes were analyzed frame-by-frame. Significant main effect of the group (experience) was observed for the number of fixation regions. Experienced soccer players had a lower number of fixation regions than the non-soccer players. Moreover, the former group presented with significantly larger percentage of fixations in the ball/foot region. These findings suggest that experienced players may use a more efficient search strategy than novices, involving fixation on a lesser number of areas in specific locations. © The Author(s) 2016.

Headache and soccer: a survey in professional soccer players of the Italian "Serie A".

PubMed

Mainardi, Federico; Alicicco, Ernesto; Maggioni, Ferdinando; Devetag, Flavio; Lisotto, Carlo; Zanchin, Giorgio

2009-02-01

The aim of the study was to assess the occurrence and the clinical features of primary headaches in a sample of players of the Italian Soccer League first division. The design of the study allowed a retrospective and prospective diagnosis of primary headaches according to the International Classification of Headache Disorders-II edition (ICHD-II), using anonymous questionnaires, which had to be filled out at regular times during the playing season. A total of 83 athletes playing in four different clubs were involved; four of them changed football team during the season and so did not complete the study. During the championship three soccer players reported headache (3.6%) with features fulfilling ICHD-II criteria for episodic tension-type headache. Important and prolonged physical effort was reported as aggravating factor in one case, but no attacks occurred during competitive matches. The same athletes had reported a personal history of episodic tension-type headache. In conclusion, the occurrence of primary headaches among professional soccer players of Italian first division championship appear to be strikingly lower, as compared to that found in the general population. A possible explanation could be given by the selection operated by a career which is not compatible with unpredictable, disabling attacks.

Physical fitness of elite Belgian soccer players by player position.

PubMed

Boone, Jan; Vaeyens, Roel; Steyaert, Adelheid; Vanden Bossche, Luc; Bourgois, Jan

2012-08-01

The purpose of this study was to gain an insight into the physical and physiological profile of elite Belgian soccer players with specific regard to the player's position on the field. The sample consisted of 289 adult players from 6 different first division teams. The players were divided into 5 subgroups (goalkeepers, center backs, full backs, midfielders, and strikers) according to their self-reported best position on the field. The subjects performed anaerobic (10-m sprint, 5 × 10-m shuttle run [SR], squat jump [SJ], and countermovement jump [CMJ]) and aerobic (incremental running protocol) laboratory tests. The strikers had significantly shorter sprinting times (5-, 5- to 10-m time, and SR) compared with the midfielders, center backs, and goalkeepers, whereas the full backs were also significantly faster compared with the goalkeepers and the center backs. The goalkeepers and the center backs displayed higher jumping heights (total mean SJ = 40.7 ± 4.6 cm and CMJ = 43.1 ± 4.9 cm) compared with the other 3 positions, whereas the strikers also jumped higher than the full backs and the midfielders did. Regarding the aerobic performance, both full backs and the midfielders (61.2 ± 2.7 and 60.4 ± 2.8 ml · min(-1) · kg(-1), respectively) had a higher VO2max compared with the strikers, center backs, and goalkeepers (56.8 ± 3.1, 55.6 ± 3.5, and 52.1 ± 5.0 ml · min(-1) · kg(-1), respectively). From this study, it could be concluded that players in different positions have different physiological characteristics. The results of this study might provide useful insights for individualized conditional training programs for soccer players. Aside from the predominant technical and tactical skills, a physical profile that is well adjusted to the position on the field might enhance game performance.

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.

Inevitable Relative Age Effects in Different Stages of the Selection Process among Male and Female Youth Soccer Players.

PubMed

Lagestad, Pål; Steen, Ingebrigt; Dalen, Terje

2018-03-31

The relative age effect (RAE) in the selection of young soccer players is a well-known phenomenon. The purpose of this study was to examine the relative age effect existing despite strategies that have been implemented to avoid its presence in the selection process. We also aimed to investigate the RAE during the three different selection stages for B13, B14 (boys), and G13, G14 (girls), and gender differences in the RAE. This was achieved by collecting data from everyone who played soccer in Troendelag, and data that would illuminate the RAE during the three stages of selection for the regional teams of the 2015/2016 season. Mann⁻Whitney U-tests and Chi-square tests were used as statistical methods. The main finding of this study is that, despite the intention to reduce RAE in the selection process according to the criterion that at least 40% of the players should be born in the second half of the year, both the early-born boys and girls are more likely to be selected. The results also show that the RAE occurs gradually, and the longer the players are in the selection process the more prominent it is. This study highlights the importance of being aware of the RAE when selecting young players.

Perfectionism and sport-specific engagement in elite youth soccer players.

PubMed

Larkin, Paul; O'Connor, Donna; Williams, A Mark

2016-07-01

It is acknowledged that the time invested in sport-specific activities contributes to higher levels of performance. However, there is limited understanding of the potential impact of personality traits, such as perfectionism, on engagement in sport-specific activities. In the current study, we examine whether elite youth soccer players who demonstrate higher and lower levels of perfectionistic strivings tendencies can be differentiated based on their sport-specific engagement. The Sport Multidimensional Perfectionism Scale 2 and an adapted Player History Questionnaire were completed by 419 elite youth male soccer players competing at the Australian age-related national youth championships (under 13, n = 133; under 14, n = 166; under 15, n = 120). A quartile split approach was used to separate higher (n = 100) and lower (n = 107) perfectionistic strivings groups. Findings revealed the higher perfectionistic strivings group accumulated more time in sport-specific activities, including coach-led practice, individual practice, peer-led play and indirect involvement in soccer when compared to individuals with lower perfectionistic strivings tendencies. Descriptive analysis indicates this equates to approximately 159 h a year (i.e. 17 h coach-led practice, 22 h individual practice, 60 h of peer-led play and 60 h of indirect involvement) more than the lower perfectionistic strivings group. In summary, the results suggest players with varying levels of perfectionistic strivings may be differentiated based on their engagement in soccer-specific activity in a sample of elite youth players in Australia, and suggests that perfectionistic strivings may have an adaptive influence on sport-specific engagement.

Estimated maturity status and perceptions of adult autonomy support in youth soccer players.

PubMed

Cumming, Sean P; Battista, Rebecca A; Martyn, Standage; Ewing, Martha E; Malina, Robert M

2006-10-01

In this study, we examined the relations between biological maturity status, body mass index, age, and perceptions of adult autonomy support in the context of youth soccer. A total of 70 female and 43 male soccer players, aged 9 - 15 years, completed three adult-specific versions (i.e. mother, father, coach) of the perceived autonomy support subscale from the Interpersonal Style Scale. The participants' percent predicted adult stature was used as an estimate of biological maturity status. Multiple linear regression analyses revealed that advanced maturity status in male players predicted lower perceptions of autonomy support from the coach. Maturity status was unrelated to perceptions of autonomy support from the coach in female soccer players, and paternal and maternal autonomy support in male and female players. Age and body mass index were unrelated to perceptions of adult (i.e. coach, mother, father) autonomy support in male and female players.

Hamstring-and-Lower-Back Flexibility in Male Amateur Soccer Players.

PubMed

van der Horst, Nick; Priesterbach, Annique; Backx, Frank; Smits, Dirk-Wouter

2017-01-01

This study investigated the hamstring-and-lower-back flexibility (HLBF) of male adult amateur soccer players, using the sit-and-reach test (SRT), with a view to obtaining population-based reference values and to determining whether SRT scores are associated with player characteristics. Cross-sectional cohort study. Teams from high-level Dutch amateur soccer competitions were recruited for participation. Dutch male high-level amateur field soccer players (n = 449) of age 18 to 40 years. Players with a hamstring injury at the moment of SRT-measurement or any other injury that prevented them from following the SRT protocol were excluded. Sit-and-reach test scores were measured and then population-based reference values were calculated as follows: >2SD below mean (defining "very low" HLBF), 1SD-2SD below mean ("low" HLBF), 1SD below mean to 1SD above mean ("normal" HLBF), 1SD-2SD above mean ("high" HLBF), and >2SD above mean ("very high" HLBF). Whether SRT scores were correlated with player characteristics was determined using a Pearson correlation coefficient or Spearman rho. Sit-and-reach test scores ranged from 0 to 43.5 cm (mean 22.0 cm, SD 9.2). The cutoff points for population-based reference values were <3.5 cm for "very low", 3.5 to 13.0 cm for "low", 13.0 to 31.0 cm for "normal", 31.0 to 40.5 cm for "high", and >40.5 cm for "very high". Sit-and-reach test scores were significantly associated with players' height (ρ = -0.132, P = 0.005), body mass index (r = 0.114, P = 0.016), and history of anterior cruciate ligament surgery (P < 0.001). This study is the first to describe the HLBF of amateur soccer players. The SRT reference values with cutoff points may facilitate evidence-based decision making regarding HLBF, and the SRT might be a useful tool to assess injury risk, performance, or for diagnostic purposes.

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.

Relationship between Nutrition Knowledge and Physical Fitness in Semiprofessional Soccer Players

PubMed Central

Nikolaidis, P. T.; Theodoropoulou, E.

2014-01-01

Whereas nutrition has a crucial role on sport performance, it is not clear to what extent nutrition knowledge is associated with physical fitness. The aim of this study was to examine the current level of nutrition knowledge of soccer players and whether this level is associated with physical fitness. Soccer players (n = 185, aged 21.3 ± 4.9 yr, weight 72.3 ± 8.4 kg, and height 177.5 ± 6.4 cm) performed a battery of physical fitness tests (sit-and-reach test, SAR; physical working capacity in heart rate 170, PWC170; and Wingate anaerobic test, WAnT) and completed an 11-item nutrition knowledge questionnaire (NKQ). Low to moderate Pearson correlations (0.15 < r < 0.34, p < 0.05) of NKQ with age, weight, height, fat free mass (FFM), SAR, peak power, and mean power of WAnT were observed. Soccer players with high score in NKQ were older (4.4 yr (2.2; 6.6), mean difference (95% confidence intervals)) and heavier (4.5 kg (0.6; 8.3)) with higher FFM (4.0 kg (1.1; 6.8)) and peak power (59 W (2; 116)) than their counterparts with low score. The moderate score in the NKQ suggests that soccer players should be targeted for nutrition education. Although the association between NKQ and physical fitness was low to moderate, there were indications that better nutrition knowledge might result in higher physical fitness and, consequently, soccer performance. PMID:25140277

Relationship between Nutrition Knowledge and Physical Fitness in Semiprofessional Soccer Players.

PubMed

Nikolaidis, P T; Theodoropoulou, E

2014-01-01

Whereas nutrition has a crucial role on sport performance, it is not clear to what extent nutrition knowledge is associated with physical fitness. The aim of this study was to examine the current level of nutrition knowledge of soccer players and whether this level is associated with physical fitness. Soccer players (n = 185, aged 21.3 ± 4.9 yr, weight 72.3 ± 8.4 kg, and height 177.5 ± 6.4 cm) performed a battery of physical fitness tests (sit-and-reach test, SAR; physical working capacity in heart rate 170, PWC170; and Wingate anaerobic test, WAnT) and completed an 11-item nutrition knowledge questionnaire (NKQ). Low to moderate Pearson correlations (0.15 < r < 0.34, p < 0.05) of NKQ with age, weight, height, fat free mass (FFM), SAR, peak power, and mean power of WAnT were observed. Soccer players with high score in NKQ were older (4.4 yr (2.2; 6.6), mean difference (95% confidence intervals)) and heavier (4.5 kg (0.6; 8.3)) with higher FFM (4.0 kg (1.1; 6.8)) and peak power (59 W (2; 116)) than their counterparts with low score. The moderate score in the NKQ suggests that soccer players should be targeted for nutrition education. Although the association between NKQ and physical fitness was low to moderate, there were indications that better nutrition knowledge might result in higher physical fitness and, consequently, soccer performance.

The Relationship between Trunk Function and Injury among Junior High School Soccer Players

PubMed Central

Nakazawa, Rie; Endo, Yasuhiro; Sakamoto, Masaaki

2013-01-01

[Purpose] The purpose of this study was to examine the relationship between trunk stability and injury among young soccer players. [Subjects and Methods] The subjects were 19 male soccer players in junior high school. The presence of injury was noted, and trunk stability was measured by using the bench test and sideways bench test, which were modified from “The 11+” exercises. [Results] There was no significant difference in endurance time in the bench test or sideways bench test between the injury group (n=9) and non-injury group (n=10). Comparison within each group revealed no significant difference in endurance time between the right and left sideways bench tests in the non-injury group; however, the time in the left sideways bench test was significantly longer than that in the right in the injury group. [Conclusion] This study suggests that there is a relationship between asymmetric trunk stability and injury. Further research investigating the relationship between asymmetric trunk function and balance skills is necessary. PMID:24259850

Active control stabilization of pelvic position in the transverse plane: an evaluation of soccer players' performance.

PubMed

Santos, Thiago Ribeiro Teles; Andrade, Juliana Alves de; Silva, Bárbara Lopes da; Garcia, Alysson Francisco Alves; Persichini Filho, José Gaspar Wild; Ocarino, Juliana de Melo; Silva, Paula Lanna

2014-08-01

To describe the capability of soccer players to stabilize pelvic position actively in the transverse plane; and, to evaluate the influence of lower limb dominance, length of exposure to soccer practice, and field position on pelvic stabilization capability. Cross-sectional. Sixty-eight soccer players from under-15 (U-15) and professional categories. Magnitude and asymmetry of pelvic tilt in the transverse plane, evaluated using the bridge test with unilateral knee extension. The magnitude of pelvic tilt did not differ between dominant and non-dominant sides, suggesting absence of relative asymmetry. However, there was difference between the sides of greater and lesser magnitude of pelvic tilt, indicating presence of absolute asymmetry. Players with shorter length of exposure to soccer practice (U-15 group) had greater pelvic tilt than players with longer length of exposure (professional group). There was no association of field position with the magnitude and asymmetry of pelvic tilt. Soccer players showed asymmetry in pelvic stabilization capability that was unrelated to lower limb dominance or field position. Athletes with longer length of exposure to soccer practice present better capability to stabilize the pelvis in the transverse plane than those with shorter length of exposure to soccer practice. Copyright © 2013 Elsevier Ltd. All rights reserved.

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.

Kinesiology tape mediates soccer-simulated and local peroneal fatigue in soccer players.

PubMed

Farquharson, Claire; Greig, Matt

2017-01-01

To investigate the efficacy of kinesiology taping in mediating the influence of fatigue on ankle sprain risk, 12 male soccer players completed single-leg dynamic balance trials pre- and post-exercise (soccer-specific protocol, isokinetic ankle inversion/eversion protocol) in each of three counter-balanced taping conditions (no tape, zinc oxide tape ZO, kinesiology tape KT). Balance was quantified as the overall stability index (OSI) and directional stability indices of platform deflection. Soccer-specific fatigue only increased OSI in the no tape condition (p = 0.03), with ZO and KT trials negating a fatigue affect. Localized fatigue increased OSI in the no tape (p = 0.01) and ZO (p = 0.05) trials, with no increase in the KT trial. A similar pattern was observed in medio-lateral and anterio-posterior balance indices. KT mediates soccer-simulated and local peroneal fatigue, with practical implications for epidemiological observations of increased injury risk during the latter stages of match play.

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.

Lumbopelvic motor control and low back pain in elite soccer players: a cross-sectional study.

PubMed

Grosdent, Stéphanie; Demoulin, Christophe; Rodriguez de La Cruz, Carlos; Giop, Romain; Tomasella, Marco; Crielaard, Jean-Michel; Vanderthommen, Marc

2016-01-01

This study aimed to investigate the relationship between the history of low back pain and quality of lumbopelvic motor control in soccer players. Forty-three male elite soccer players (mean age, 18.2 ± 1.4 years) filled in questionnaires related to low back pain and attended a session to assess lumbopelvic motor control by means of five tests (the bent knee fall out test, the knee lift abdominal test, the sitting knee extension test, the waiter's bow and the transversus abdominis test). A physiotherapist, blinded to the medical history of the participants, scored (0 = failed, 1 = correct) the performance of the players for each of the tests resulting in a lumbopelvic motor control score ranging from 0 to 5. Forty-seven per cent of the soccer players reported a disabling low back pain episode lasting at least two consecutive days in the previous year. These players scored worse lumbopelvic motor control than players without a history of low back pain (lumbopelvic motor control score of 1.8 vs. 3.3, P < 0.01). The between-groups difference was particularly marked for the bent knee fall out test, the knee lift abdominal test and the transversus abdominis test (P < 0.01). In conclusion, most soccer players with a history of low back pain had an altered lumbopelvic motor control. Further research should examine whether lumbopelvic motor control is etiologically involved in low back pain episodes in soccer players.

Are Female Soccer Players at an Increased Risk of Second Anterior Cruciate Ligament Injury Compared With Their Athletic Peers?

PubMed

Allen, Melissa M; Pareek, Ayoosh; Krych, Aaron J; Hewett, Timothy E; Levy, Bruce A; Stuart, Michael J; Dahm, Diane L

2016-10-01

Female soccer players have a well-known risk for anterior cruciate ligament (ACL) injury, but few studies have reported on second ACL injuries in this population. To (1) report the rates of subsequent ACL injury (ipsilateral graft rupture or contralateral tear) in competitive female soccer players, (2) compare these rates with those of other female athletes of similar competitive level, (3) determine risk factors for second ACL injury, and (4) report clinical outcome scores in this population. Cohort study; Level of evidence, 3. The medical records at a single institution were reviewed for female patients who were injured during a competitive athletic event and treated with primary ACL reconstruction (ACLR) between 1998 and 2013. Patients were followed for a mean of 68.8 months postoperatively (range, 24-115.2 months). Clinical outcome was obtained via Lysholm and International Knee Documentation Committee (IKDC) scores. Soccer players were matched 1:1 to non-soccer athletes for age, activity level, and graft type. A total of 180 female ACLR patients with a mean ± SD age of 19.6 ± 6.9 years met the study inclusion and exclusion criteria (90 soccer players and 90 non-soccer players). Soccer players sustained more second ACL injuries, including both graft failures (11% vs 1%; P < .01) and contralateral ACL tears (17% vs 4%; P < .01), compared with non-soccer players. Of the 67 patients who returned to soccer after ACLR (mean age, 17.5 years; range, 13-27 years), significantly more had graft tears compared with those who did not return to soccer (15% vs 0%, respectively; P = .04); however, the difference in contralateral ACL tears (19% for returning players vs 9% for those who did not return; P = .34) was not significant. Relatively older age (odds ratio, 1.5 per year; P = .03) was a significant risk factor for ACL graft tear but not for contralateral ACL injury. Both groups had similar mean Lysholm (96 vs 95) and IKDC scores (95 vs 96) at final follow-up. Twenty

Laterality related to the successive selection of Dutch national youth soccer players.

PubMed

Verbeek, Jan; Elferink-Gemser, Marije T; Jonker, Laura; Huijgen, Barbara C H; Visscher, Chris

2017-11-01

In the general population, estimates of left-foot preference are around 20%. In soccer, specific tasks create positional demands, requiring 40% of the players to be left-footed. Whether and how this is related to the selection of players is unknown. To examine the successive selection of soccer players for Dutch national youth teams in relation to foot preference, 280 youth players (age = 16.2 ± 1.08 years) were monitored from the U16 through the U19 teams over the last 5 years. No difference in successive selection between left- and right-footed players was found (p < 0.05). Regardless of foot preference, more than 50% of the selected players were deselected out of a national youth team after 2 years. On average, 31% of the national youth players were left-footed, which is higher than expected, based on population estimates (χ 2 (1) = 37.49, p < 0.001, w = 0.27). However, there was an under-representation of left-footed players, based on expected positional demands (i.e., attack, midfield, defence) (χ 2 (1) = 16.83, p < 0.001, w = 0.18). The conclusion is that left-foot preference increases the probability of selection in Dutch national youth soccer teams.

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.

How do expert soccer players encode visual information to make decisions in simulated game situations?

PubMed

Poplu, Gérald; Ripoll, Hubert; Mavromatis, Sébastien; Baratgin, Jean

2008-09-01

The aim of this study was to determine what visual information expert soccer players encode when they are asked to make a decision. We used a repetition-priming paradigm to test the hypothesis that experts encode a soccer pattern's structure independently of the players' physical characteristics (i.e., posture and morphology). The participants were given either realistic (digital photos) or abstract (three-dimensional schematic representations) soccer game patterns. The results showed that the experts benefited from priming effects regardless of how abstract the stimuli were. This suggests that an abstract representation of a realistic pattern (i.e., one that does not include visual information related to the players'physical characteristics) is sufficient to activate experts'specific knowledge during decision making. These results seem to show that expert soccer players encode and store abstract representations of visual patterns in memory.

Mental Fatigue and Spatial References Impair Soccer Players' Physical and Tactical Performances

PubMed Central

Coutinho, Diogo; Gonçalves, Bruno; Travassos, Bruno; Wong, Del P.; Coutts, Aaron J.; Sampaio, Jaime E

2017-01-01

This study examined the effects of mental fatigue and additional corridor and pitch sector lines on players' physical and tactical performances during soccer small-sided games. Twelve youth players performed four Gk+6vs6+Gk small-sided games. Prior to the game, one team performed a motor coordination task to induce mental fatigue, while the other one performed a control task. A repeated measures design allowed to compare players' performances across four conditions: (a) with mental fatigue against opponents without mental fatigue in a normal pitch (MEN), (b) with mental fatigue on a pitch with additional reference lines (#MEN); (c) without mental fatigue against mentally fatigued opponents on a normal pitch (CTR); and (d) without mental fatigue on a pitch with reference lines (#CTR). Player's physical performance was assessed by the distance covered per minute and the number of accelerations and decelerations (0.5–3.0 m/s2; > −3.0 m/s2). Positional data was used to determine individual (spatial exploration index, time synchronized in longitudinal and lateral directions) and team-related variables (length, width, speed of dispersion and contraction). Unclear effects were found for the physical activity measures in most of the conditions. There was a small decrease in time spent laterally synchronized and a moderate decrease in the contraction speed when MEN compared to the CTR. Also, there was a small decrease in the time spent longitudinally synchronized during the #MEN condition compared to MEN. The results showed that mental fatigue affects the ability to use environmental information and players' positioning, while the additional reference lines may have enhanced the use of less relevant information to guide their actions during the #MEN condition. Overall, coaches could manipulate the mental fatigue and reference lines to induce variability and adaptation in young soccer players' behavior. PMID:28983273

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

Maximal heart rate in soccer players: measured versus age-predicted.

PubMed

Nikolaidis, Pantelis T

2015-01-01

Although maximal heart rate (HR max) is widely used to assess exercise intensity in sport training, and particularly in soccer, there are limited data with regards to the use of age-based prediction equations of HR max in soccer players. The aim of this study was to compare the measured-HR max with two prediction equations (Fox-HR max = 220 - age and Tanaka-HR max = 208 - 0.7 × age) in soccer players. Adolescent (n = 162, 15.8 ± 1.5 years) and adult players (n = 158, 23.4 ± 4.6 years), all members of competitive clubs, voluntarily performed a graded exercise field test (Conconi protocol) to assess HR max . The measured-HR max (197.6 ± 9.4 bpm in total, 200.2 ± 7.9 bpm in adolescent players, and 195.0 ± 10.0 bpm in adult players) was explained by the formula HR max = 212.3 - 0.75 × age (r = -0.41, standard error of the estimate = 8.6). In the total sample, Fox-HR max overestimated measured-HR max [mean difference (95% confidence intervals) = 2.8 bpm (1.6; 3.9)], while Tanaka-HR max underestimated HR max [-3.3 bpm (-4.5; -2.2)]. In adolescents, Fox-HR max overestimated measured-HR max [4.0 bpm (2.5; 5.5)] and Tanaka-HR max underestimated HR max [- 3.2 bpm (-4.7; -1.8)]. In adults, Tanaka-HR max underestimated HR max [-5.0 bpm (-5.3; -4.7)], while there was not any difference between Fox-HR max and measured-HR max [1.6 bpm (-3.4; 0.2)]. The results of this study failed to validate two widely used prediction equations in a large sample of soccer players, indicating the need for a sport-specific equation. On the other hand, the new equation that we presented should be investigated further by future studies before being adopted by coaches and fitness trainers.

Difference in kick motion of adolescent soccer players in presence and absence of low back pain.

PubMed

Tojima, Michio; Torii, Suguru

2018-01-01

Many adolescent soccer players experience low back pain (LBP). However, there are no reports studying the kick motion of adolescent soccer players experiencing LBP. This study aimed to clarify the kick motion of adolescent soccer players in the presence and absence of LBP. We recruited 42 adolescent soccer players and divided them into two groups according to the presence of LBP (LBP group, n=22) and absence of LBP (NBP group, n=20). We measured real-time kick motion using a three-dimensional motion analysis system. We placed 65 spherical markers on each anatomical landmark and calculated the angle of the lumbar spine, center of mass (COM) of the whole body, and displacement of the support foot. We used an unpaired t-test to compare the data between the groups. Compared with the NBP group, the LBP group showed a lateral shift in COM, which increased the duration of kick motion. The presence of LBP affected the posterior positioning of the support foot and restricted the player's lumbar spine from bending laterally. A lateral shift in COM and larger rotation of the lumbar spine could stress the lumbar spine during kick motion. Therefore, coaches and athletic trainers should pay attention to soccer players' lumbar spine rotation and the COM shift during kick motion. This would be important for preventing LBP in adolescent soccer players. Copyright © 2017 Elsevier B.V. All rights reserved.

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

Effect of Core Training Program on Physical Functional Performance in Female Soccer Players

ERIC Educational Resources Information Center

Taskin, Cengiz

2016-01-01

The purpose of this study was to determine the effect of core training program on speed, acceleration, vertical jump, and standing long jump in female soccer players. A total of 40 female soccer players volunteered to participate in this study. They were divided randomly into 1 of 2 groups: core training group (CTG; n = 20) and control group (CG;…

Nonverbal behavior in soccer: the influence of dominant and submissive body language on the impression formation and expectancy of success of soccer players.

PubMed

Furley, Philip; Dicks, Matt; Memmert, Daniel

2012-02-01

In the present article, we investigate the effects of specific nonverbal behaviors signaling dominance and submissiveness on impression formation and outcome expectation in the soccer penalty kick situation. In Experiment 1, results indicated that penalty takers with dominant body language are perceived more positively by soccer goalkeepers and players and are expected to perform better than players with a submissive body language. This effect was similar for both video and point-light displays. Moreover, in contrast to previous studies, we found no effect of clothing (red vs. white) in the video condition. In Experiment 2, we used the implicit association test to demonstrate that dominant body language is implicitly associated with a positive soccer player schema whereas submissive body language is implicitly associated with a negative soccer player schema. The implications of our findings are discussed with reference to future implications for theory and research in the study of person perception in sport.

The Investigation of the Motor Skills of "U" Kategories Soccer Players Who Have Recreative Involvement in Other Sports

ERIC Educational Resources Information Center

Göksu, Ömer Can; Yüksek, Selami; Ölmez, Cengiz

2018-01-01

This study was conducted to examine the effects of sports activities other than soccer on 10-15-year-old soccer players' motor skills. The sample included 146 registered soccer players in the U category (U10-U15) of the Turkish Football Federation's Aslantepe, Çeliktepe and Seyrantepe clubs. The players participated in this study on a voluntary…

No Effect of Generalized Joint Hypermobility on Injury Risk in Elite Female Soccer Players: A Prospective Cohort Study.

PubMed

Blokland, Donna; Thijs, Karin M; Backx, Frank J G; Goedhart, Edwin A; Huisstede, Bionka M A

2017-02-01

Although it has been suggested that generalized joint hypermobility (GJH) is a risk factor for injury in soccer players, it remains unclear whether this applies to elite female soccer players. To investigate whether GJH is a risk factor for injury in elite female soccer players. Cohort study; Level of evidence, 2. Elite female soccer players in the Netherlands were screened at the start of the 2014-2015 competitive season. GJH was assessed using the Beighton score. Soccer injuries and soccer exposure were registered throughout the entire season. Poisson regression was performed to calculate incidence risk ratios (IRRs) using different cutoff points of the Beighton score (≥3, ≥4, and ≥5) to indicate GJH. Of the 114 players included in the study, 20 were classified as hypermobile (Beighton score ≥4). The mean (±SD) injury incidence per player was 8.40 ± 9.17 injuries/1000 hours of soccer, with no significant difference between hypermobile and nonhypermobile players. GJH was not a risk factor for injuries when using Beighton score cutoff points of ≥3 (IRR = 1.06 [95% CI, 0.74-1.50]; P = .762), ≥4 (IRR = 1.10 [95% CI, 0.72-1.68]; P = .662), or ≥5 (IRR = 1.15 [95% CI, 0.68-1.95]; P = .602). Similarly, GJH was not a significant risk factor for thigh, knee, or ankle injuries evaluated separately. This study indicates that GJH is not a risk factor for injuries in elite female soccer players, irrespective of Beighton score cutoff point. Hypermobile players at this elite level might have improved their active stability and/or used braces to compensate for joint laxity.

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

Validation of Field Methods to Assess Body Fat Percentage in Elite Youth Soccer Players.

PubMed

Munguia-Izquierdo, Diego; Suarez-Arrones, Luis; Di Salvo, Valter; Paredes-Hernandez, Victor; Alcazar, Julian; Ara, Ignacio; Kreider, Richard; Mendez-Villanueva, Alberto

2018-05-01

This study determined the most effective field method for quantifying body fat percentage in male elite youth soccer players and developed prediction equations based on anthropometric variables. Forty-four male elite-standard youth soccer players aged 16.3-18.0 years underwent body fat percentage assessments, including bioelectrical impedance analysis and the calculation of various skinfold-based prediction equations. Dual X-ray absorptiometry provided a criterion measure of body fat percentage. Correlation coefficients, bias, limits of agreement, and differences were used as validity measures, and regression analyses were used to develop soccer-specific prediction equations. The equations from Sarria et al. (1998) and Durnin & Rahaman (1967) reached very large correlations and the lowest biases, and they reached neither the practically worthwhile difference nor the substantial difference between methods. The new youth soccer-specific skinfold equation included a combination of triceps and supraspinale skinfolds. None of the practical methods compared in this study are adequate for estimating body fat percentage in male elite youth soccer players, except for the equations from Sarria et al. (1998) and Durnin & Rahaman (1967). The new youth soccer-specific equation calculated in this investigation is the only field method specifically developed and validated in elite male players, and it shows potentially good predictive power. © Georg Thieme Verlag KG Stuttgart · New York.

Peer relationships in adolescent competitive soccer: associations to perceived motivational climate, achievement goals and perfectionism.

PubMed

Ommundsen, Yngvar; Roberts, Glyn C; Lemyre, Pierre-Nicolas; Miller, Blake W

2005-09-01

The aim of this study was to examine the relationship between the perceived motivational climate, achievement goals, perfectionism and indices of peer relationships in a sample of young male and female Norwegian soccer players. The sample consisted of 1719 experienced soccer players (1231 males, 488 females) aged 12-19 years (mean = 14.9 years) participating in the Norway Cup international youth soccer competition. The players responded to a questionnaire measuring perceived peer acceptance and quality of friendship in soccer, perceived motivational climate, achievement goals and perfectionism in soccer. Canonical correlation analyses revealed that young female players who perceived the motivational climate as predominantly mastery oriented, and who were moderately task oriented and scored negatively on maladaptive perfectionism, reported better relations with their peers in soccer. Constructive peer relations were evident in that they scored positively on companionship with their best friend in soccer; they perceived this friend as being loyal and allowing of free discussion, and they reported being socially accepted by their peers in soccer. Mirroring these findings, young male players who perceived the motivational climate as predominantly performance oriented, who had a moderately negative score on task orientation but a quite strong positive score on maladaptive perfectionism, reported negative relationships with peers in terms of these aspects. They also reported being in conflict with their best soccer friend. The findings suggest that the qualities of motivation have a systematic relationship with peer acceptance and the quality of friendship in male and female youth soccer.

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.

Resynthesis of muscle glycogen after soccer specific performance examined by 13C-magnetic resonance spectroscopy in elite players.

PubMed

Zehnder, M; Rico-Sanz, J; Kühne, G; Boutellier, U

2001-05-01

The purpose of this study was to examine using 13C-magnetic resonance spectroscopy whether muscle glycogen (Gly) utilized during a simulation of a fatiguing soccer match followed by repeated sprints would be resynthesized during the next 24 h while players consumed their habitual diet. A group of 12 elite young players [mean age 17.5 (SD 0.8) years, mean body mass 68.9 (SD 6.6) kg, mean height 177.0 (SD 5.4) cm] participated in the study. Average muscle Gly content before the simulation was 134 (SD 16) mmol.(kg wet mass)-1 and decreased during the test (P < 0.001) to 80 (SD 29) mmol.(kg wet mass)-1. The value had increased (P < 0.01) to 122 (SD 33) mmol.(kg wet mass)-1 24 h later but it was not significantly different from the value obtained before the soccer test. Dietary analysis of the food intake during the 24 h after the running test revealed that players consumed an average of 2,681 (SD 970) kcal.day-1. Mean daily protein, fat, and carbohydrate (CHO) intakes were 85 (SD 29), 99 (SD 44), and 327 (SD 116) g, respectively. The mean amounts of CHO intake normalised to body mass were 4.8 (SD 1.8) g.(kg body mass)-1. In conclusion, the results of this study showed that despite a CHO intake of less than 5 g.(kg body mass)-1 the habitual diet of soccer players might be sufficient to replenish in 24 h the muscle Gly utilized during soccer specific performance. However, cumulative deficits of about 10% in Gly replenishment as found in the present study might provoke decrements in performance. Thus, players should pay attention to their habitual diets and add more carbohydrates to replenish their daily deficits and perhaps increase their basal levels of intake.

Physical Performance and Anthropometric Characteristics of Male South African University Soccer Players.

PubMed

Kubayi, Alliance; Paul, Yvonne; Mahlangu, Prescott; Toriola, Abel

2017-12-01

Soccer is the most popular sport worldwide. Despite its global acclaim, scientific studies of soccer have tended to focus on tactics and techniques, thereby neglecting the physical and physiological profile of the players. Therefore, the purpose of this study was to examine physical and anthropometric characteristics of male South African university soccer players. Twenty-seven male soccer players aged 19 to 24 (mean age: 22.1 years; s = 1.5 years) volunteered to participate in the study. The results showed that goalkeepers (77.5 ± 9.7 kg) and defenders (68.2 ± 6.5 kg) were the heaviest compared to players in other playing positions. The goalkeepers also had the highest percentage of body fat (11.3 ± 2.3%), in contrast to midfielders who had the lowest body fat content (9.1 ± 0.9%). With regard to flexibility, defenders (45.1 ± 4.9 cm) and midfielders (45.9 ± 5.4 cm) performed better than goalkeepers (37.1 ± 4.3 cm) and strikers (40.1 ± 3.4 cm). Midfielders (57.2 ± 3.1 ml 1 ·kg -1 ·min 1 ) and defenders (56.1 ± 5.1 ml 1 ·kg -1 ·min 1 ) had significantly higher values of maximal oxygen uptake (VO 2max ) than goalkeepers (47.9 ± 0.2 ml -1 ·kg -1 ·min -1 ) and strikers (49.8 ± 6.2 ml -1 ·kg -1 ·min -1 ). No significant (p > 0.05) differences were observed for all other variables, with the exception of body height, body mass, and VO 2max . It was therefore concluded that sports scientists and coaches should tailor conditioning programmes in soccer according to players' positions in view of the implications for successful performance.

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.

Soccer-Specific Warm-Up and Lower Extremity Injury Rates in Collegiate Male Soccer Players

PubMed Central

Grooms, Dustin R.; Palmer, Thomas; Onate, James A.; Myer, Gregory D.; Grindstaff, Terry

2013-01-01

Context: A number of comprehensive injury-prevention programs have demonstrated injury risk-reduction effects but have had limited adoption across athletic settings. This may be due to program noncompliance, minimal exercise supervision, lack of exercise progression, and sport specificity. A soccer-specific program described as the F-MARC 11+ was developed by an expert group in association with the Federation Internationale de Football Association (FIFA) Medical Assessment and Research Centre (F-MARC) to require minimal equipment and implementation as part of regular soccer training. The F-MARC 11+ has been shown to reduce injury risk in youth female soccer players but has not been evaluated in an American male collegiate population. Objective: To investigate the effects of a soccer-specific warm-up program (F-MARC 11+) on lower extremity injury incidence in male collegiate soccer players. Design: Cohort study. Setting: One American collegiate soccer team followed for 2 seasons. Patients or Other Participants: Forty-one male collegiate athletes aged 18–25 years. Intervention(s): The F-MARC 11+ program is a comprehensive warm-up program targeting muscular strength, body kinesthetic awareness, and neuromuscular control during static and dynamic movements. Training sessions and program progression were monitored by a certified athletic trainer. Main Outcome Measure(s): Lower extremity injury risk and time lost to lower extremity injury. Results: The injury rate in the referent season was 8.1 injuries per 1000 exposures with 291 days lost and 2.2 injuries per 1000 exposures and 52 days lost in the intervention season. The intervention season had reductions in the relative risk (RR) of lower extremity injury of 72% (RR = 0.28, 95% confidence interval = 0.09, 0.85) and time lost to lower extremity injury (P < .01). Conclusions: This F-MARC 11+ program reduced overall risk and severity of lower extremity injury compared with controls in collegiate-aged male soccer

Reliability of the Tuck Jump Injury Risk Screening Assessment in Elite Male Youth Soccer Players.

PubMed

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

2016-06-01

Read, PJ, Oliver, JL, de Ste Croix, MBA, Myer, GD, and Lloyd, RS. Reliability of the tuck jump injury risk screening assessment in elite male youth soccer players. J Strength Cond Res 30(6): 1510-1516, 2016-Altered neuromuscular control has been suggested as a mechanism for injury in soccer players. Ligamentous injuries most often occur during dynamic movements, such as decelerations from jump-landing maneuvers where high-risk movement patterns are present. The assessment of kinematic variables during jump-landing tasks as part of a preparticipation screen is useful in the identification of injury risk. An example of a field-based screening tool is the repeated tuck jump assessment. The purpose of this study was to analyze the within-subject variation of the tuck jump screening assessment in elite male youth soccer players. Twenty-five pre-peak height velocity (PHV) and 25 post-PHV elite male youth soccer players from the academy of a professional English soccer club completed the assessment. A test-retest design was used to explore the within-subject intersession reliability. Technique was graded retrospectively against the 10-point criteria set out in the screening protocol using two-dimensional video cameras. The typical error range reported for tuck jump total score (0.90-1.01 in pre-PHV and post-PHV players respectively) was considered acceptable. When each criteria was analyzed individually, kappa coefficient determined that knee valgus was the only criterion to reach substantial agreement across the two test sessions for both groups. The results of this study suggest that although tuck jump total score may be reliably assessed in elite male youth soccer players, caution should be applied in solely interpreting the composite score due to the high within-subject variation in a number of the individual criteria. Knee valgus may be reliably used to screen elite youth male soccer players for this plyometric technique error and for test-retest comparison.

Differences in injury risk and characteristics between Dutch amateur and professional soccer players.

PubMed

van Beijsterveldt, A M C Anne-Marie; Stubbe, J H; Schmikli, S L; van de Port, I G L; Backx, F J G

2015-03-01

To compare the incidence and characteristics of injuries between Dutch amateur and professional male soccer players during one entire competition season. A prospective two-cohort design. During the 2009-2010 season, 456 Dutch male amateur soccer players and 217 professional players were prospectively followed. Information on injuries and individual exposure to all soccer activities were recorded in both cohorts. Injuries were recorded using the time-loss definition. In total, 424 injuries were recorded among 274 of the amateur players (60.1% injured players) and 286 injuries were sustained by 136 (62.7% injured players) of the professional players (p=0.52). Compared to the professionals, the injury incidence during training sessions was higher among amateurs (p=0.01), but the injury incidence among professionals was higher during matches (p<0.001). Professional players also had a higher incidence of minimal injuries (p<0.001), whereas the incidence of moderate and severe injuries was higher for amateurs (all p<0.001). Lastly, professional players sustained more overuse injuries (p=0.02), whereas amateurs reported more recurrent injuries (p<0.001). The above-mentioned differences in injury rates between amateur and professional players in the Netherlands might be explained by the difference in the level at which they play, since factors like the availability of medical support and/or the team size may influence the injury risk and characteristics. Copyright © 2014 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

The diagnostic and prognostic value of ultrasonography in soccer players with acute hamstring injuries.

PubMed

Petersen, Jesper; Thorborg, Kristian; Nielsen, Michael Bachmann; Skjødt, Thomas; Bolvig, Lars; Bang, Niels; Hölmich, Per

2014-02-01

An injury to the hamstring muscle complex is the most common injury in soccer. Ultrasound of acute hamstring injuries is often used as a clinical tool for diagnosing hamstring injuries and guiding players in when they can return to play. To (1) investigate the characteristic sonographic findings of acute hamstring injuries in soccer players, (2) compare the mean injury severity (time to return to play) in injured players with and without sonographically verified abnormalities, and (3) correlate the length of the injured area and absence from soccer play (time to return to play) to investigate if ultrasonography can be used as a prognostic indicator of time to return to play. Case series; Level of evidence, 4. Players from 50 teams participating in 1 of the top 5 Danish soccer divisions were followed in the period from January to December 2008. Of 67 players with acute hamstring injuries, 51 underwent ultrasonographic examination of the injured thigh and were included in this study. Ultrasonographic examinations were performed 1 to 10 days after injury (mean, 5.2 ± 3.0 days), and sonographic findings were present in 31 of 51 cases (61%). Two thirds of the injuries were to the biceps femoris muscle and one third to the semitendinosus muscle. No total ruptures were documented. The 51 acute hamstring injuries resulted in absence from soccer of a mean 25.4 ± 15.7 days per injury, with no significant difference between players with and without sonographically verified abnormalities (P = .41). No correlation existed between the length of the injured area and injury severity (r = 0.19, P = .29). The biceps femoris is the most commonly injured hamstring muscle detected by ultrasound, and more than half of the injuries are intramuscular. Because neither the presence of sonographic findings nor the size of the findings was correlated with time to return to play in injured soccer players, the prognosis of hamstring injuries should not be guided by these findings alone.

Comparıson of the Heart Rate and Blood Lactate Responses of Different Small Sided Games in Young Soccer Players.

PubMed

Köklü, Yusuf; Alemdaroğlu, Utku

2016-09-29

The purpose of this study was to compare the percentage of maximum heart rate (%HRmax), blood lactate (La - ), and rating of perceived exertion (RPE, CR-10) responses across different formats of small-sided games (SSG) in elite young soccer players. Fourteen players (average age 16.7 ± 0.6 years; height 177.6 ± 4.1 cm; body mass 66.3 ± 4.7 kg; average training age 6.7 ± 1.6 years; percentage of body fat 8.4 ± 2.6%) volunteered to perform the YoYo intermittent recovery test (level 1) and eight bouts of soccer drills including 2-a-side, 3-a-side, and 4-a-side games without goalkeepers in random order at two-day intervals. Heart rates were monitored throughout the SSGs, whereas the RPE and venous blood lactate were determined at the end of the last bout of each SSG. The differences in La - , %HRmax, and RPE either across the different SSGs or between the bouts were identified using 3 × 8 (games × exercise bouts) two-way analysis of variance with repeated measures. Significant differences were found in terms of La - , RPE, and %HRmax among the different types of SSG ( p ≤ 0.05). 3-a-side and 4-a-side games elicited significantly higher responses than 2-a-side games in terms of %HRmax ( p ≤ 0.05), whereas 4-a-side games resulted in significantly lower La - and RPE responses compared to 2-a-side and 3-a-side games. The results of this study show that physiological responses differ according to the numbers of players involved in small-sided games. Therefore, it can be concluded that 3-a-side and 4-a-side games could be more effective in improving high intensity aerobic performance than 2-a-side games, which in turn are more appropriate for developing anaerobic performance.

Posterior tibial slope as a risk factor for anterior cruciate ligament rupture in soccer players.

PubMed

Senişik, Seçkin; Ozgürbüz, Cengizhan; Ergün, Metin; Yüksel, Oğuz; Taskiran, Emin; Işlegen, Cetin; Ertat, Ahmet

2011-01-01

Anterior cruciate ligament (ACL) is the primary stabilizer of the knee. An impairment of any of the dynamic or static stability providing factors can lead to overload on the other factors and ultimately to deterioration of knee stability. This can result in anterior tibial translation and rupture of the ACL. The purpose of this study was to examine the influence of tibial slope on ACL injury risk on soccer players. A total of 64 elite soccer players and 45 sedentary controls were included in this longitudinal and controlled study. The angle between the tibial mid-diaphysis line and the line between the anterior and posterior edges of the medial tibial plateau was measured as the tibial slope via lateral radiographs. Individual player exposure, and injuries sustained by the participants were prospectively recorded. Eleven ACL injuries were documented during the study period. Tibial slope was not different between soccer players and sedentary controls. Tibial slope in the dominant and non-dominant legs was greater for the injured players compared to the uninjured players. The difference reached a significant level only for the dominant legs (p < 0.001). While the tibial slopes of the dominant and non-dominant legs were not different on uninjured players (p > 0.05), a higher tibial slope was observed in dominant legs of injured players (p < 0.05). Higher tibial slope on injured soccer players compared to the uninjured ones supports the idea that the tibial slope degree might be an important risk factor for ACL injury. Key pointsDominant legs' tibial slopes of the injured players were significantly higher compared to the uninjured players (p < 0.001).Higher tibial slope was determined in dominant legs compared to the non-dominant side, for the injured players (p = 0.042). Different tibial slope measures in dominant and non-dominant legs might be the result of different loading and/or adaptation patterns in soccer.

Energy and macronutrient intakes of professional football (soccer) players.

PubMed

Maughan, R J

1997-03-01

To examine the dietary habits of professional soccer players at two Scottish Premier League clubs during the competitive season. A study of the dietary intake of 51 professional soccer players with two different clubs was carried out by the seven day weighed intake method. Physical characteristics of the two groups of players were similar, with only small differences in age and body mass but no difference in height and body fat. Mean (SD) daily energy intake for club A was 11.0 (2.6) MJ, and for club B 12.8 (2.2) MJ. The higher energy intake at club B was largely accounted for by a higher (P < 0.005) fat intake (118 v 93 g d-1): there was no difference in the absolute amounts of protein, carbohydrate, or alcohol consumed. When expressed as a fraction of total energy intake, mean protein intake was higher (P < 0.05) and fat intake lower (P < 0.01) at club A. The mean energy intake of these players was not high compared with athletes in endurance sports. Fractional contribution of the macronutrients to total energy intake was broadly similar to that of the general population.

Iliopsoas and Gluteal Muscles Are Asymmetric in Tennis Players but Not in Soccer Players

PubMed Central

Sanchis-Moysi, Joaquin; Idoate, Fernando; Izquierdo, Mikel; Calbet, Jose A. L.; Dorado, Cecilia

2011-01-01

Purpose To determine the volume and degree of asymmetry of iliopsoas (IL) and gluteal muscles (GL) in tennis and soccer players. Methods IL and GL volumes were determined using magnetic resonance imaging (MRI) in male professional tennis (TP) and soccer players (SP), and in non-active control subjects (CG) (n = 8, 15 and 6, respectively). Results The dominant and non-dominant IL were hypertrophied in TP (24 and 36%, respectively, P<0.05) and SP (32 and 35%, respectively, P<0.05). In TP the asymmetric hypertrophy of IL (13% greater volume in the non-dominant than in the dominant IL, P<0.01) reversed the side-to-side relationship observed in CG (4% greater volume in the dominant than in the contralateral IL, P<0.01), whilst soccer players had similar volumes in both sides (P = 0.87). The degree of side-to-side asymmetry decreased linearly from the first lumbar disc to the pubic symphysis in TP (r = −0.97, P<0.001), SP (r = −0.85, P<0.01) and CG (r = −0.76, P<0.05). The slope of the relationship was lower in SP due to a greater hypertrophy of the proximal segments of the dominant IL. Soccer and CG had similar GL volumes in both sides (P = 0.11 and P = 0.19, for the dominant and contralateral GL, respectively). GL was asymmetrically hypertrophied in TP. The non-dominant GL volume was 20% greater in TP than in CG (P<0.05), whilst TP and CG had similar dominant GL volumes (P = 0.14). Conclusions Tennis elicits an asymmetric hypertrophy of IL and reverses the normal dominant-to-non-dominant balance observed in non-active controls, while soccer is associated to a symmetric hypertrophy of IL. Gluteal muscles are asymmetrically hypertrophied in TP, while SP display a similar size to that observed in controls. It remains to be determined whether the different patterns of IL and GL hypertrophy may influence the risk of injury. PMID:21829539

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

Physiological responses and time-motion characteristics of 4-a-side small-sided game in young soccer players: the influence of different team formation methods.

PubMed

Köklü, Yusuf; Ersöz, Gülfem; Alemdaroğlu, Utku; Aşç, Alper; Ozkan, Ali

2012-11-01

The purpose of this study was to examine the influence of different team formation methods on the physiological responses to and time-motion characteristics of 4-a-side small-sided games (SSG4) in young soccer players. Thirty-two young soccer players (age 16.2 ± 0.7 years; height 172.9 ± 6.1 cm; body mass 64.1 ± 7.7 kg) voluntarily participated in this study. Anthropometric measurements, technical tests, and maximum oxygen uptake (V[Combining Dot Above]O2max) tests were carried out on the players. The SSG4 teams were then created using 4 different methods: according to the coaches' subjective evaluation (CE), technical scores (TS), V[Combining Dot Above]O2max (AP), and V[Combining Dot Above]O2max multiplied by TSs (CG). The teams thus created played 4 bouts of SSG4 at 2-day intervals. During the SSG4, heart rate (HR) responses, distance covered, and time spent in HRmax zones were recorded. In addition, rating of perceived exertion (RPE) and blood lactate level (La) were determined at the end of the last bout of each SSG4. Percent of HRmax (%HRmax), La, and RPE responses during SSG4 were significantly higher for teams chosen according to AP and CG compared with that according to CE and TS (p < 0.05). In addition, teams chosen by AP and CG spent significantly more time in zone 4 (>90% HRmax ) and covered a greater distance in the high-intensity running zone (>18 km·h) than did teams formed according to TS. Moreover, AP teams covered significantly greater total distance than TS teams did (p < 0.05). In conclusion, to spend more time in both the high-intensity HR zone and the high-intensity running zone, the teams in SSG4 should be formed according to the players' V[Combining Dot Above]O2max values or the values calculated using both the V[Combining Dot Above]O2max and technique scores.

Free-sugar, total-sugar, fibre, and micronutrient intake within elite youth British soccer players: a nutritional transition from schoolboy to fulltime soccer player.

PubMed

Naughton, Robert J; Drust, Barry; O'Boyle, Andy; Abayomi, Julie; Mahon, Elizabeth; Morton, James P; Davies, Ian G

2017-05-01

It is recommended that soccer players consume a high carbohydrate diet to augment performance. However, growing evidence suggests that there is a link between high free-sugar (FS) intake (>5% total energy intake; TEI) and metabolic diseases. Furthermore, foods that are often high in sugar, such as processed foods, are typically lacking in nutrient quality. We therefore analysed total-sugar, FS, dietary fibre, and micronutrient intake of players from an English Premier League academy under (U) 18 (n = 13), U15/16 (n = 25), and U13/14 (n = 21) using a 7-day food diary. Data were compared with current United Kingdom (UK) dietary reference value (DRV) for FS via a t test. The U13/14s (10% ± 18%) and U15/16s (11% ± 30%) both consumed higher amounts of FS in comparison with the UK DRV of 5% TEI (P < 0.01); conversely, the U18s did not exceed the DRV (5% ± 13%). Furthermore, FS intake of the U18s was significantly lower than the U13/14s and U15/16s (P < 0.01). Dietary fibre was below the DRV (25 g/day for U13/14 and U15/16s; 30 g/day for U18s) for all squads (19.0 ± 4.7, 19.6 ± 8.3, 17.1 ± 4.2 g/day, respectively), but not different between squads. Additionally, micronutrient reference intakes were generally met. In conclusion, we provide novel data on dietary sugar, fibre, and micronutrient intake within elite youth soccer players. We report an apparent "nutritional transition" from schoolboy to fulltime soccer player, with U18s showing a significantly lower intake of sugar in comparison with younger squads, and a similar intake of FS to the UK DRVs. Practitioners should target improving player education around sugar and fibre consumption.

In-season training periodization of professional soccer players

PubMed Central

Mendez-Villanueva, A; Martínez-Santos, R

2017-01-01

The aim of this study was to quantify the seasonal perceived respiratory and muscular training loads (i.e., sRPEres-TL and sRPEmus-TL) completed by elite-oriented young professional soccer players. Twenty-four players (20.3 ± 2.0 years) belonging to the same reserve team of a Spanish La Liga club participated in this study. Only the players that were available to train for a whole week with the team and also to play the weekly game were considered: Starters, players that participated in the match for at least 45 min and Non-Starters, players that did not participate or played less than 45 minutes in the match. The competitive period was analysed after the division into 5x6-8 week blocks and 35x1 week microcycles. Data were also analysed with respect to number of days before the immediate match. Weekly TL variation across the in-season blocks was trivial-small for both groups except between Block 2 and Block 3 (ES= moderate). Substantial TL differences (ES= small–very likely) were found between training days, the TL pattern being a progressive increase up to MD-3 followed by a decrease until MD-1. Except for the match, sRPEres-/sRPEmus-TL was very similar between Starters and Non-Starters. In summary, perceived TL across the season displayed limited variation. Coaches periodized training contents to attain the highest weekly TL 72 hours before the match to progressively unload the players between MD-3 and the match day. The data revealed that the TL arising from the weekly game was solely responsible for the observed higher weekly TL of Starters in comparison with Non-Starters. PMID:28566808

Proportionate mortality of Italian soccer players: is amyotrophic lateral sclerosis an occupational disease?

PubMed

Belli, Stefano; Vanacore, Nicola

2005-01-01

The objective of the study is to investigate the mortality experience of Italian soccer players and to discuss the findings in the light of possible long term effects of doping. Standardized proportionate mortality ratio (SPMR) and standardized proportionate cancer mortality ratio (SPCMR) were computed for 350 deceased subjects deriving from a list of about 24,000 active Italian soccer players from 1960 to 1996 in the three top leagues (A, B and C). When considering SPMRs, there is a substantial adherence of observed to expected mortality, with the only exception of mortality for diseases of the nervous system (13 obs. vs. 6 exp.) mainly explained by an excess of amyotrophic lateral sclerosis (8 obs. vs 0.69 exp.). As far as SPCMRs are concerned, some digestive cancers (namely: colon cancer, liver cancer and pancreas cancer) show a doubled risk. A high risk for amyotrophic lateral sclerosis is observed among Italian soccer players. Epidemiological data on association between sport and Amyotrophic Lateral Sclerosis (ALS) are contrasting. On the basis of the overall available evidence we suggest a possible connection between dietary supplements or drugs used to enhance sporting performance and ALS pathogenesis. Further epidemiological studies are needed to confirm these specific mortality risks among soccer players.

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

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

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.

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

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.

How Do Expert Soccer Players Encode Visual Information to Make Decisions in Simulated Game Situations?

ERIC Educational Resources Information Center

Poplu, Gerald; Ripoll, Hubert; Mavromatis, Sebastien; Baratgin, Jean

2008-01-01

The aim of this study was to determine what visual information expert soccer players encode when they are asked to make a decision. We used a repetition-priming paradigm to test the hypothesis that experts encode a soccer pattern's structure independently of the players' physical characteristics (i.e., posture and morphology). The participants…

Soccer small-sided games in young players: rule modification to induce higher physiological responses

PubMed Central

Chtourou, H; Dellal, A; Chaouachi, A; Chamari, K

2017-01-01

The aim of this study was to identify the physiological responses of 3 forms of players’ numbers during two different games rules of small-sided games (SSG: stop-ball vs. small-goals rules). Eighteen youth amateur soccer players (age 13.5±0.7 years; height 168.9±6.1cm; body mass 63.1±7.7 kg) participated in this study and performed 3 SSGs with varying players’ number (2vs.2; 3vs.3 and 4vs.4): stop-ball SSG (SB-SSG) vs. small-goals SSG (SG-SSG) in a randomized and counter-balanced order on a constant pitch dimension (20×25m). The players performed 4×4 min SSG with 2-min of passive recovery in-between. Heart rate (HR), (expressed in bpm and % HRmax), lactate ([La-]), and rating of perceived exertion (RPE) were collected during each session. SB-SSG induced the higher HR values in comparison with the SG-SSG for the 3 game formats (2vs.2; 3vs.3 and 4vs.4). Also, compared with SG-SSG, SB-SSG induced the higher HR values during 2vs.2 compared with 4vs.4 games rules (178 vs. 174 and 175 vs. 171 bpm, respectively). However, the SB-SSG was more intense compared with SG-SSG in the 2 vs. 2 game rule compared with the two others (3 vs.3 and 4 vs. 4) for [La-] and RPE (7.58 vs. 7; 7.25 vs. 6.75 and 6.5 vs. 6.16 mmol ∙ L-1, and 7.75 vs. 7.33; 7.41 vs. 7.08 and 7.16 vs. 6.83, respectively). Therefore, the use of 2 vs. 2 and 3 vs. 3 SSG with SB-SSG seems to represent an alternative to coaches to increase cardiovascular and metabolic demands in youth soccer players. PMID:28566810

A physiological evaluation of professional soccer players.

PubMed

Raven, P B; Gettman, L R; Pollock, M L; Cooper, K H

1976-12-01

The purpose of this study was to evaluate the physiological functions of a professional soccer team in the North American Soccer League (NASL). Eighteen players were evaluated on cardiorespiratory function, endurance performance, body composition, blood chemistry, and motor fitness measures near the end of their competitive season. The following means were observed: age, 26 yrs; height, 176 cm; weight 75.5 kg; resting heart rate, 50 beats/min; maximum heart rate (MHR), 188 beats/min; maximum oxygen intake (VO2 max), 58.4 ml/kg-min-1; maximum ventilation (VEmax BTPS), 154 L/min; body fat, 9.59%; 12-min run, 1.86 miles; and Illinois agility run, 15.6 secs. Results on resting blood pressure, serum lipids, vital capacity, flexibility, upper body strength, and vertical jump tests were comparable to values found for the sedentary population. Comparing the results with previously collected data on professional American Football backs indicated that the soccer players were shorter; lighter in body weight; higher in VO2 max (4 ml/kg-min-1) and body fat (1.8%); and similar in MHR, VE max, and VC. The 12-min run scores were similar to the initial values observed for the 1970 Brazilian World Cup Team. The agility run results were superior to data collected from other groups. Their endurance capabilities, agility, and low percent of body fat clearly differentiate them from the sedentary population and show them to be similar to that of professional American football backs.

A physiological evaluation of professional soccer players.

PubMed Central

Raven, P. B.; Gettman, L. R.; Pollock, M. L.; Cooper, K. H.

1976-01-01

The purpose of this study was to evaluate the physiological functions of a professional soccer team in the North American Soccer League (NASL). Eighteen players were evaluated on cardiorespiratory function, endurance performance, body composition, blood chemistry, and motor fitness measures near the end of their competitive season. The following means were observed: age, 26 yrs; height, 176 cm; weight 75.5 kg; resting heart rate, 50 beats/min; maximum heart rate (MHR), 188 beats/min; maximum oxygen intake (VO2 max), 58.4 ml/kg-min-1; maximum ventilation (VEmax BTPS), 154 L/min; body fat, 9.59%; 12-min run, 1.86 miles; and Illinois agility run, 15.6 secs. Results on resting blood pressure, serum lipids, vital capacity, flexibility, upper body strength, and vertical jump tests were comparable to values found for the sedentary population. Comparing the results with previously collected data on professional American Football backs indicated that the soccer players were shorter; lighter in body weight; higher in VO2 max (4 ml/kg-min-1) and body fat (1.8%); and similar in MHR, VE max, and VC. The 12-min run scores were similar to the initial values observed for the 1970 Brazilian World Cup Team. The agility run results were superior to data collected from other groups. Their endurance capabilities, agility, and low percent of body fat clearly differentiate them from the sedentary population and show them to be similar to that of professional American football backs. PMID:1009297

Intrinsic risk factors of noncontact ankle sprains in soccer: a prospective study on 100 professional players.

PubMed

Fousekis, Konstantinos; Tsepis, Elias; Vagenas, George

2012-08-01

Ankle sprain is an extremely common injury in soccer players. Despite extensive research, the intrinsic cause of this injury under noncontact conditions remains unclear. To identify intrinsic risk factors for noncontact ankle sprains in professional soccer players. Cohort study; Level of evidence, 2 One hundred professional soccer players were assessed in the preseason for potential risk factors of noncontact ankle sprains. The assessment included (A) ankle joint asymmetries (right-left) in isokinetic muscle strength, flexibility, proprioception, and stability; (B) somatometric asymmetries; (C) previous injuries; and (D) lateral dominance traits. Noncontact ankle sprains were prospectively recorded and diagnosed for a full competition period (10 months). Seventeen of the players sustained at least 1 noncontact ankle sprain. Logistic regression revealed that players with (A) eccentric isokinetic ankle flexion strength asymmetries (odds ratio [OR] = 8.88; 95% confidence interval [CI], 1.95-40.36, P = .005), (B) increased body mass index (OR = 8.16; 95% CI, 1.42-46.63, P = .018), and (C) increased body weight (OR = 5.72; 95% CI, 1.37-23.95, P = .017 ) each had a significantly higher risk of a noncontact ankle sprain. A trend for younger players (OR = 0.28; 95% CI, 0.061-1.24, P = .092) and for players with ankle laxity asymmetries (OR = 3.38; 95% CI, 0.82-14.00, P = .093) to be at greater risk for ankle sprain was also apparent to the limit of statistical significance (.05 < P < .10). Functional strength asymmetries of the ankle flexors and increased body mass index and body weight raise the propensity for ankle sprains in professional soccer players. Age and asymmetries in ankle laxity are potential factors worth revisiting, as there was an indication for younger players and players with ankle instability to be at higher risk for ankle injury. Proper preseason evaluation may improve prevention strategies for this type of injury in soccer.

RELIABILITY OF THE TUCK JUMP INJURY RISK SCREENING ASSESSMENT IN ELITE MALE YOUTH SOCCER PLAYERS

PubMed Central

READ, PAUL; OLIVER, JON L.; DE STE CROIX, MARK B.A.; MYER, GREGORY D.; LLOYD, RHODRI S.

2015-01-01

Altered neuromuscular control has been suggested as a mechanism for injury in soccer players. Ligamentous injuries most often occur during dynamic movements, such as decelerations from jump-landing maneuvers where high risk movement patterns are present. The assessment of kinematic variables during jump-landing tasks as part of a pre-participation screen is useful in the identification of injury risk. An example of a field-based screening tool is the repeated tuck jump assessment. The purpose of this study was to analyze the within-subject variation of the tuck jump screening assessment in elite male youth soccer players. 25 pre and 25 post-peak height velocity (PHV) elite male youth soccer players from the academy of a professional English soccer club completed the assessment. A test, re-test design was used to explore the within-subject inter-session reliability. Technique was graded retrospectively against the 10-point criteria set out in the screening protocol using two-dimensional video cameras. The typical error range reported for tuck jump total score (0.90 – 1.01 in pre and post-PHV players respectively) was considered acceptable. When each criteria was analyzed individually, Kappa coefficient determined that knee valgus was the only criterion to reach substantial agreement across the two test sessions for both groups. The results of this study suggest that although tuck jump total score may be reliably assessed in elite male youth soccer players, caution should be applied in solely interpreting the composite score due to the high within-subject variation in a number of the individual criteria. Knee valgus may be reliably used to screen elite youth male soccer players for this plyometric technique error and for test, re-test comparison. PMID:26562715

The Importance of Vitaminsfor Soccer Players.

PubMed

Eskici, Günay

2015-12-01

Soccer is one of the most widely played and complex sports in the world, where success depends on technical, tactical and physical skills of the players. Studies to improve performance in soccer have often focused on technique and tactics. However, nutrition is one of the most important factors influencing athletic performance of the players. The duration of matches is long and the training is intense. This leads to increased requirements for energy and nutrients, as well as increased reactive oxygen radicals and hence increased muscle damage. Vitamins are micronutrients that a living organism requires in trace quantities for health. As these assume crucial functions in the body, the performance of the player is negatively affected particularly during long-term deficiency. Beta-carotene, C and E vitamins are antioxidants that protect against oxygen radicals. In case of their deficiency, oxidative stress and muscle fatigue increases. Vitamin D is involved in maintaining mineral balance, and it increases absorption of dietary calcium and phosphorus. In case of vitamin D deficiency, injuries resulting from the musculoskeletal system might increase. B Vitamins (B1, B2, niacin, B6, B12, biotin, folic acid and pantothenic acid) perform duties such as energy production, absorption and transport of iron and blood cell production. Athletes who follow an energy-restricted and imbalanced diet might develop vitamin deficiency. In such a case, supplements can be used as recommended by the doctor/dietician. It is further reported that supplement use by athletes who have an adequate and balanced nutrition does not increase performance.

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

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

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.

Sleep Hygiene and Recovery Strategies in Elite Soccer Players.

PubMed

Nédélec, Mathieu; Halson, Shona; Delecroix, Barthélémy; Abaidia, Abd-Elbasset; Ahmaidi, Said; Dupont, Gregory

2015-11-01

In elite soccer, players are frequently exposed to various situations and conditions that can interfere with sleep (e.g., playing night matches interspersed with 3 days; performing activities demanding high levels of concentration close to bedtime; use of products containing caffeine or alcohol in the period preceding bedtime; regular daytime napping throughout the week; variable wake-up times or bedtime), potentially leading to sleep deprivation. We outline simple, practical, and pharmaceutical-free sleep strategies that are coordinated to the constraints of elite soccer in order to promote sleep. Sleep deprivation is best alleviated by sleep extension; however, sleep hygiene strategies (i.e., consistent sleep pattern, appropriate napping, and active daytime behaviors) can be utilized to promote restorative sleep. Light has a profound impact on sleep, and sleep hygiene strategies that support the natural environmental light-dark cycle (i.e., red-light treatment prior to sleep, dawn-simulation therapy prior to waking) and prevent cycle disruption (i.e., filtering short wavelengths prior to sleep) may be beneficial to elite soccer players. Under conditions of inordinate stress, techniques such as brainwave entrainment and meditation are promising sleep-promoting strategies, but future studies are required to ascertain the applicability of these techniques to elite soccer players. Consuming high-electrolyte fluids such as milk, high-glycemic index carbohydrates, some forms of protein immediately prior to sleep, as well as tart cherry juice concentrate and tryptophan may promote rehydration, substrate stores replenishment, muscle-damage repair and/or restorative sleep. The influence of cold water immersion performed close to bedtime on subsequent sleep is still debated. Conversely, the potential detrimental effects of sleeping medication must be recognized. Sleep initiation is influenced by numerous factors, reinforcing the need for future research to identify such

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.

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.

Eccentric and Isometric Hip Adduction Strength in Male Soccer Players With and Without Adductor-Related Groin Pain: An Assessor-Blinded Comparison.

PubMed

Thorborg, Kristian; Branci, Sonia; Nielsen, Martin Peter; Tang, Lars; Nielsen, Michael Bachmann; Hölmich, Per

2014-02-01

Adductor-related pain is the most common clinical finding in soccer players with groin pain and can be a long-standing problem affecting physical function and performance. Hip adductor weakness has been suggested to be associated with this clinical entity, although it has never been investigated. To investigate whether isometric and eccentric hip strength are decreased in soccer players with adductor-related groin pain compared with asymptomatic soccer controls. The hypothesis was that players with adductor-related groin pain would have lower isometric and eccentric hip adduction strength than players without adductor-related groin pain. Cross-sectional study; Level of evidence, 3. Male elite and subelite players from 40 teams were contacted. In total, 28 soccer players with adductor-related groin pain and 16 soccer players without adductor-related groin pain (asymptomatic controls) were included in the study. In primary analysis, the dominant legs of 21 soccer players with adductor-related groin pain (≥4 weeks duration) were compared with the dominant legs of 16 asymptomatic controls using a cross-sectional design. The mean age of the symptomatic players was 24.5 ± 2.5 years, and the mean age of the asymptomatic controls was 22.9 ± 2.4 years. Isometric hip strength (adduction, abduction, and flexion) and eccentric hip strength (adduction) were assessed with a handheld dynamometer using reliable test procedures and a blinded assessor. Eccentric hip adduction strength was lower in soccer players with adductor-related groin pain in the dominant leg (n = 21) compared with asymptomatic controls (n = 16), namely 2.47 ± 0.49 versus 3.12 ± 0.43 N·m/kg, respectively (P < .001). No other hip strength differences were observed between symptomatic players and asymptomatic controls for the dominant leg (P = .35-.84). Large eccentric hip adduction strength deficits were found in soccer players with adductor-related groin pain compared with asymptomatic soccer players

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).

Multivariate Profiles of Selected versus Non-Selected Elite Youth Brazilian Soccer Players

PubMed Central

Alves, Isabella S.; Padilha, Maickel B.; Casanova, Filipe; Puggina, Enrico F.; Maia, José

2017-01-01

Abstract This study determined whether a multivariate profile more effectively discriminated selected than non-selected elite youth Brazilian soccer players. This examination was carried out on 66 youth soccer players (selected, n = 28, mean age 16.3 ± 0.1; non-selected, n = 38, mean age 16.7 ± 0.4) using objective instruments. Multivariate profiles were assessed through anthropometric characteristics, biological maturation, tactical-technical skills, and motor performance. The Student’s t-test identified that selected players exhibited significantly higher values for height (t = 2.331, p = 0.02), lean body mass (t = 2.441, p = 0.01), and maturity offset (t = 4.559, p < 0.001), as well as performed better in declarative tactical knowledge (t = 10.484, p < 0.001), shooting (t = 2.188, p = 0.03), dribbling (t = 5.914, p < 0.001), speed – 30 m (t = 8.304, p < 0.001), countermovement jump (t = 2.718, p = 0.008), and peak power tests (t = 2.454, p = 0.01). Forward stepwise discriminant function analysis showed that declarative tactical knowledge, running speed –30 m, maturity offset, dribbling, height, and peak power correctly classified 97% of the selected players. These findings may have implications for a highly efficient selection process with objective measures of youth players in soccer clubs. PMID:29339991

Effects of Plyometric and Sprint Training on Physical and Technical Skill Performance in Adolescent Soccer Players.

PubMed

Sáez de Villarreal, Eduardo; Suarez-Arrones, Luis; Requena, Bernardo; Haff, Gregory G; Ferrete, Carlos

2015-07-01

To determine the influence of a short-term combined plyometric and sprint training (9 weeks) within regular soccer practice on explosive and technical actions of pubertal soccer players during the in-season. Twenty-six players were randomly assigned to 2 groups: control group (CG) (soccer training only) and combined group (CombG) (plyometric + acceleration + dribbling + shooting). All players trained soccer 4 times per week and the experimental groups supplemented the soccer training with a proposed plyometric-sprint training program for 40 minutes (2 days per weeks). Ten-meter sprint, 10-m agility with and without ball, CMJ and Abalakov vertical jump, ball-shooting speed, and Yo-Yo intermittent endurance test were measured before and after training. The experimental group followed a 9-week plyometric and sprint program (i.e., jumping, hurdling, bouncing, skipping, and footwork) implemented before the soccer training. Baseline-training results showed no significant differences between the groups in any of the variables tested. No improvement was found in the CG; however, meaningful improvement was found in all variables in the experimental group: CMJ (effect size [ES] = 0.9), Abalakov vertical jump (ES = 1.3), 10-m sprint (ES = 0.7-0.9), 10-m agility (ES = 0.8-1.2), and ball-shooting speed (ES = 0.7-0.8). A specific combined plyometric and sprint training within regular soccer practice improved explosive actions compared with conventional soccer training only. Therefore, the short-term combined program had a beneficial impact on explosive actions, such as sprinting, change of direction, jumping, and ball-shooting speed which are important determinants of match-winning actions in soccer performance. Therefore, we propose modifications to current training methodology for pubertal soccer players to include combined plyometric and speed training for athlete preparation in this sport.

Energy and macronutrient intakes of professional football (soccer) players.

PubMed Central

Maughan, R J

1997-01-01

OBJECTIVE: To examine the dietary habits of professional soccer players at two Scottish Premier League clubs during the competitive season. METHODS: A study of the dietary intake of 51 professional soccer players with two different clubs was carried out by the seven day weighed intake method. RESULTS: Physical characteristics of the two groups of players were similar, with only small differences in age and body mass but no difference in height and body fat. Mean (SD) daily energy intake for club A was 11.0 (2.6) MJ, and for club B 12.8 (2.2) MJ. The higher energy intake at club B was largely accounted for by a higher (P < 0.005) fat intake (118 v 93 g d-1): there was no difference in the absolute amounts of protein, carbohydrate, or alcohol consumed. When expressed as a fraction of total energy intake, mean protein intake was higher (P < 0.05) and fat intake lower (P < 0.01) at club A. CONCLUSIONS: The mean energy intake of these players was not high compared with athletes in endurance sports. Fractional contribution of the macronutrients to total energy intake was broadly similar to that of the general population. PMID:9132211

Physical Performance and Anthropometric Characteristics of Male South African University Soccer Players

PubMed Central

Paul, Yvonne; Mahlangu, Prescott; Toriola, Abel

2017-01-01

Abstract Soccer is the most popular sport worldwide. Despite its global acclaim, scientific studies of soccer have tended to focus on tactics and techniques, thereby neglecting the physical and physiological profile of the players. Therefore, the purpose of this study was to examine physical and anthropometric characteristics of male South African university soccer players. Twenty-seven male soccer players aged 19 to 24 (mean age: 22.1 years; s = 1.5 years) volunteered to participate in the study. The results showed that goalkeepers (77.5 ± 9.7 kg) and defenders (68.2 ± 6.5 kg) were the heaviest compared to players in other playing positions. The goalkeepers also had the highest percentage of body fat (11.3 ± 2.3%), in contrast to midfielders who had the lowest body fat content (9.1 ± 0.9%). With regard to flexibility, defenders (45.1 ± 4.9 cm) and midfielders (45.9 ± 5.4 cm) performed better than goalkeepers (37.1 ± 4.3 cm) and strikers (40.1 ± 3.4 cm). Midfielders (57.2 ± 3.1 ml1·kg−1·min1) and defenders (56.1 ± 5.1 ml1·kg−1·min1) had significantly higher values of maximal oxygen uptake (VO2max) than goalkeepers (47.9 ± 0.2 ml−1·kg−1·min−1) and strikers (49.8 ± 6.2 ml−1·kg−1·min−1). No significant (p > 0.05) differences were observed for all other variables, with the exception of body height, body mass, and VO2max. It was therefore concluded that sports scientists and coaches should tailor conditioning programmes in soccer according to players’ positions in view of the implications for successful performance. PMID:29339995

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

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

The older, the wider: On-field tactical behavior of elite-standard youth soccer players in small-sided games.

PubMed

Olthof, Sigrid B H; Frencken, Wouter G P; Lemmink, Koen A P M

2015-06-01

Young soccer players need excellent tactical skills to reach the top. Tactical behavior emerges through interactions between opposing teams. However, few studies have focused on on-field tactical behavior of teams with talented soccer players. Therefore, this study aimed to determine teams' tactical behavior during small-sided games in two age categories, Under-17 and Under-19. Positional data of thirty-nine elite-standard soccer players were collected during twenty-four small-sided games to calculate longitudinal and lateral inter-team distances, stretch indices and length per width ratios. Corresponding interaction patterns and game-to-game variability were also determined. Under-19 showed a significantly larger lateral stretch index and a significantly lower length per width ratio compared with Under-17. Furthermore, teams of both age groups showed similar large proportions of in-phase behavior. Variability of tactical performance measures within and between games was similar for Under-17 and Under-19. Variability within games seems to be functional for attacking teams for creating goal-scoring opportunities. In conclusion, the main difference was that Under-19 adopted a wider pitch dispersion than Under-17, represented by a larger lateral stretch index and smaller length per width ratio. Coach instructions and training exercises should be directed at exploiting pitch width to increase the pursuit of goal-scoring. Copyright © 2015 Elsevier B.V. All rights reserved.

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

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 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.

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.

Developmental activities and the acquisition of superior anticipation and decision making in soccer players.

PubMed

Roca, André; Williams, A Mark; Ford, Paul R

2012-01-01

We examined whether soccer players with varying levels of perceptual-cognitive expertise can be differentiated based on their engagement in various types and amounts of activity during their development. A total of 64 participants interacted with life-size video clips of 11 versus 11 dynamic situations in soccer, viewed from the first-person perspective of a central defender. They were required to anticipate the actions of their opponents and to make appropriate decisions as to how best to respond. Response accuracy scores were used to categorise elite players (n = 48) as high- (n = 16) and low-performing (n = 16) participants. A group of recreational players (n = 16) who had lower response accuracy scores compared to the elite groups acted as controls. The participation history profiles of players were recorded using retrospective recall questionnaires. The average hours accumulated per year during childhood in soccer-specific play activity was the strongest predictor of perceptual-cognitive expertise. Soccer-specific practice activity during adolescence was also a predictor, albeit its impact was relatively modest. No differences were reported across groups for number of other sports engaged in during development, or for some of the key milestones achieved. A number of implications for talent development are discussed.

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.

The Influence of Restricted Visual Feedback on Dribbling Performance in Youth Soccer Players.

PubMed

Fransen, Job; Lovell, Thomas W J; Bennett, Kyle J M; Deprez, Dieter; Deconinck, Frederik J A; Lenoir, Matthieu; Coutts, Aaron J

2017-04-01

The aim of the current study was to examine the influence of restricted visual feedback using stroboscopic eyewear on the dribbling performance of youth soccer players. Three dribble test conditions were used in a within-subjects design to measure the effect of restricted visual feedback on soccer dribbling performance in 189 youth soccer players (age: 10-18 y) classified as fast, average or slow dribblers. The results showed that limiting visual feedback increased dribble test times across all abilities. Furthermore, the largest performance decrement between stroboscopic and full vision conditions was in fast dribblers, showing that fast dribblers were most affected by reduced visual information. This may be due to a greater dependency on visual feedback at increased speeds, which may limit the ability to maintain continuous control of the ball. These findings may have important implications for the development of soccer dribbling ability.

Allergies and Exercise-Induced Bronchoconstriction in a Youth Academy and Reserve Professional Soccer Team.

PubMed

Bougault, Valérie; Drouard, François; Legall, Franck; Dupont, Grégory; Wallaert, Benoit

2017-09-01

A high prevalence of respiratory allergies and exercise-induced bronchoconstriction (EIB) has been reported among endurance athletes. This study was designed to analyze the frequency of sensitization to respiratory allergens and EIB in young soccer players. Prospective cohort design. Youth academy and reserve professional soccer team during the seasons 2012 to 2013 and 2013 to 2014. Eighty-five soccer players (mean age: 20 ± 4 years) participated. Players underwent skin prick tests (SPTs) during the seasons 2012 to 2013 and 2013 to 2014. Spirometry and a eucapnic voluntary hyperpnea test were performed on soccer players during the first season 2012 to 2013 (n = 51) to detect EIB. Two self-administered questionnaires on respiratory history and allergic symptoms (European Community Respiratory Health Survey and Allergy Questionnaire for Athletes) were also distributed during both seasons (n = 59). The number of positive SPTs, exercise-induced respiratory symptoms, presence of asthma, airway obstruction, and EIB. Forty-nine percent of players were sensitized to at least one respiratory allergen, 33% reported an allergic disease, 1 player presented airway obstruction at rest, and 16% presented EIB. Factors predictive of EIB were self-reported exercise-induced symptoms and sensitization to at least 5 allergens. Questioning players about exercise-induced respiratory symptoms and allergies as well as spirometry at the time of the inclusion medical checkup would improve management of respiratory health of soccer players and would constitute inexpensive preliminary screening to select players requiring indirect bronchial provocation test or SPTs. This study showed that despite low frequencies, EIB and allergies are underdiagnosed and undertreated in young soccer players.

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.

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.

Analysis of Cohesion and Collective Efficacy Profiles for the Performance of Soccer Players

PubMed Central

Leo, Francisco M.; Sánchez-Miguel, Pedro A.; Sánchez-Oliva, David; Amado, Diana; García-Calvo, Tomás

2013-01-01

The principal aims of the study were to define different profiles of cohesion and perceived efficacy in soccer players and to measure their differences in performance. The subjects were 235 soccer players in the under-18 category who played in the National League in Spain and 15 coaches whose ages ranged from 29 to 45 years. Diverse instruments to assess cohesion, perceived efficacy, and expectations of success were used in the study. Moreover, we measured playing time and performance. The results of the study proved the existence of four cohesion and efficacy profiles that presented significant differences in expectations of success, playing time, and performance. Furthermore, significant differences were found in the distribution of players in the teams as a function of performance. The main conclusion of this study is that soccer players with higher cohesion and collective efficacy levels belonged to teams that completed the season at the top-level classification. In contrast, athletes with low cohesion and collective efficacy usually played in unsuccessful teams. Coaches and sports psychologists are encouraged to promote both social and task cohesion and collective efficacy to enhance team performance. PMID:24511358

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.

Symptoms from repeated intentional and unintentional head impact in soccer players

PubMed Central

Stewart, Walter F.; Kim, Namhee; Ifrah, Chloe S.; Lipton, Richard B.; Bachrach, Tamar A.; Zimmerman, Molly E.; Kim, Mimi

2017-01-01

Objective: To determine the rate and differential contribution of heading vs unintentional head impacts (e.g., head to head, goal post) to CNS symptoms in adult amateur soccer players. Methods: Amateur soccer players completed baseline and serial on-line 2-week recall questionnaires (HeadCount) and reported (1) soccer practice and games, (2) heading and unintentional soccer head trauma, and (3) frequency and severity (mild to very severe) of CNS symptoms. For analysis, CNS symptoms were affirmed if one or more moderate, severe, or very severe episodes were reported in a 2-week period. Repeated measures logistic regression was used to assess if 2-week heading exposure (i.e., 4 quartiles) or unintentional head impacts (i.e., 0, 1, 2+) were associated with CNS symptoms. Results: A total of 222 soccer players (79% male) completed 470 HeadCount questionnaires. Mean (median) heading/2 weeks was 44 (18) for men and 27 (9.5) for women. One or more unintentional head impacts were reported by 37% of men and 43% of women. Heading-related symptoms were reported in 20% (93 out of 470) of the HeadCounts. Heading in the highest quartile was significantly associated with CNS symptoms (odds ratio [OR] 3.17, 95% confidence interval [CI] 1.57–6.37) when controlling for unintentional exposure. Those with 2+ unintentional exposures were at increased risk for CNS symptoms (OR 6.09, 95% CI 3.33–11.17) as were those with a single exposure (OR 2.98, 95% CI 1.69–5.26) when controlling for heading. Conclusions: Intentional (i.e., heading) and unintentional head impacts are each independently associated with moderate to very severe CNS symptoms. PMID:28148633

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

A vision framework for the localization of soccer players and ball on the pitch using Handycams

NASA Astrophysics Data System (ADS)

Vilas, Tiago; Rodrigues, J. M. F.; Cardoso, P. J. S.; Silva, Bruno

2015-03-01

The current performance requirements in soccer make imperative the use of new technologies for game observation and analysis, such that detailed information about the teams' actions is provided. This paper summarizes a framework to collect the soccer players and ball positions using one or more Full HD Handycams, placed no more than 20cm apart in the stands, as well as how this framework connects to the FootData project. The system was based on four main modules: the detection and delimitation of the soccer pitch, the ball and the players detection and assignment to their teams, the tracking of players and ball and finally the computation of their localization (in meters) in the pitch.

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

Postactivation Potentiation of the Plantar Flexors Does Not Directly Translate to Jump Performance in Female Elite Young Soccer Players.

PubMed

Prieske, Olaf; Maffiuletti, Nicola A; Granacher, Urs

2018-01-01

High-intensity muscle actions have the potential to temporarily improve muscle contractile properties (i.e., postactivation potentiation, PAP) thereby inducing acute performance enhancements. There is evidence that balance training can improve performance during strength exercises. Taking these findings together, the purpose of this study was to examine the acute effects of a combined balance and strength (B+S) exercise vs. a strength only (S) exercise on twitch contractile properties, maximum voluntary strength, and jump performance in young athletes. Female elite young soccer players ( N = 12) aged 14-15 years conducted three experimental conditions in randomized order: S included 3 sets of 8-10 dynamic leg extensions at 80% of the 1-repetition maximum, B+S consisted of 3 sets of 40 s double-leg stances on a balance board prior to leg extensions (same as S), and a resting control period. Before and 7 min after exercise, participants were tested for their electrically-evoked isometric twitches (i.e., twitch peak torque, twitch rate of torque development) and maximal voluntary contraction (MVC) torque of the plantar flexor muscles. Additionally, countermovement (CMJ) and drop jump (DJ) performances (i.e., CMJ/DJ height, DJ ground contact time) were assessed. Significant effects of condition on twitch contractile properties ( p < 0.05, d = 1.1) and jump performance outputs ( p < 0.05, 1.1 ≤ d ≤ 1.2) were found. Post-hoc tests revealed that S compared to control produced larger PAP for twitch peak torques by trend ( p = 0.07, d = 1.8, 33 vs. 21%) and significantly larger PAP for twitch rate of torque development ( p < 0.05, d = 2.4, 55 vs. 43%). Following B+S compared to control, significant improvements in CMJ height ( p < 0.01, d = 1.9, 3%) and DJ contact time were found ( p < 0.01, d = 2.0, 10%). This study revealed protocol-specific acute performance improvements. While S resulted in significant increases in twitch contractile properties, B+S produced

Postactivation Potentiation of the Plantar Flexors Does Not Directly Translate to Jump Performance in Female Elite Young Soccer Players

PubMed Central

Prieske, Olaf; Maffiuletti, Nicola A.; Granacher, Urs

2018-01-01

High-intensity muscle actions have the potential to temporarily improve muscle contractile properties (i.e., postactivation potentiation, PAP) thereby inducing acute performance enhancements. There is evidence that balance training can improve performance during strength exercises. Taking these findings together, the purpose of this study was to examine the acute effects of a combined balance and strength (B+S) exercise vs. a strength only (S) exercise on twitch contractile properties, maximum voluntary strength, and jump performance in young athletes. Female elite young soccer players (N = 12) aged 14–15 years conducted three experimental conditions in randomized order: S included 3 sets of 8–10 dynamic leg extensions at 80% of the 1-repetition maximum, B+S consisted of 3 sets of 40 s double-leg stances on a balance board prior to leg extensions (same as S), and a resting control period. Before and 7 min after exercise, participants were tested for their electrically-evoked isometric twitches (i.e., twitch peak torque, twitch rate of torque development) and maximal voluntary contraction (MVC) torque of the plantar flexor muscles. Additionally, countermovement (CMJ) and drop jump (DJ) performances (i.e., CMJ/DJ height, DJ ground contact time) were assessed. Significant effects of condition on twitch contractile properties (p < 0.05, d = 1.1) and jump performance outputs (p < 0.05, 1.1 ≤ d ≤ 1.2) were found. Post-hoc tests revealed that S compared to control produced larger PAP for twitch peak torques by trend (p = 0.07, d = 1.8, 33 vs. 21%) and significantly larger PAP for twitch rate of torque development (p < 0.05, d = 2.4, 55 vs. 43%). Following B+S compared to control, significant improvements in CMJ height (p < 0.01, d = 1.9, 3%) and DJ contact time were found (p < 0.01, d = 2.0, 10%). This study revealed protocol-specific acute performance improvements. While S resulted in significant increases in twitch contractile properties, B+S produced

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.

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.

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.

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.

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

Caffeine and Creatine Content of Dietary Supplements Consumed by Brazilian Soccer Players.

PubMed

Inácio, Suelen Galante; de Oliveira, Gustavo Vieira; Alvares, Thiago Silveira

2016-08-01

Caffeine and creatine are ingredients in the most popular dietary supplements consumed by soccer players. However, some products may not contain the disclosed amounts of the ingredients listed on the label, compromising the safe usage and the effectiveness of these supplements. Therefore, the aim of this study was to evaluate the content of caffeine and creatine in dietary supplements consumed by Brazilian soccer players. The results obtained were compared with the caffeine content listed on the product label. Two batches of the supplement brands consumed by ≥ 50% of the players were considered for analysis. The quantification of caffeine and creatine in the supplements was determined by a high-performance liquid chromatography system with UV detector. Nine supplements of caffeine and 7 supplements of creatine met the inclusion criteria for analysis. Eight brands of caffeine and five brands of creatine showed significantly different values (p < .05) as compared with the values stated on the label. There were no significant differences between the two batches of supplements analyzed, except for one caffeine supplement. It can be concluded that caffeine and creatine dietary supplements consumed by Brazilian soccer players present inaccurate values listed on the label, although most presented no difference among batches. To ensure consumer safety and product efficacy, accurate information on caffeine and creatine content should be provided on all dietary supplement labels.

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.

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

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.

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.

Inter-individual Variability in Soccer Players of Different Age Groups Playing Different Positions

PubMed Central

Nikolaidis, Pantelis; Ziv, Gal; Lidor, Ronnie; Arnon, Michal

2014-01-01

The purpose of this study was twofold: (a) to profile physical characteristics and motor abilities of three age groups of soccer players – under 14 years, 14–17, and over 17, playing different positions – goalkeepers, defenders, midfielders, and forwards; and (b) to examine the inter-individual variability among the players in each age group in all physical and physiological measurements performed in the study. In addition, anthropometric, power, strength, and flexibility tests were administered. Findings showed large inter-individual variability in all three age groups and in all playing positions. Differences between playing positions were found only in the 14–17 group (body mass) and in the over-17 group (body height, body mass, fat-free mass, and mean power in the Wingate Anaerobic Test). Due to the observed large inter-individual variability, it was concluded that the findings obtained in the physical and physiological tests should be interpreted with caution when attempting to differentiate between successful and unsuccessful soccer players, as well as when trying to predict future success in soccer. PMID:25031689

Comparison of Blood Lipids, Blood Pressures and Left Ventricular Cavity Dimension between Soccer Players and Non-Athletes

ERIC Educational Resources Information Center

Gokhan, Ismail; Kurkcu, Recep; Cekin, Resul

2013-01-01

In this study, it was aimed to compare the investigate the effects of regular exercise on blood lipids, blood pressure and left ventricular cavity dimensions function between soccer players and non-athletes in football players. This study consisted included a total of 30 subjects, including an experimental group including 18 soccer players…

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.

Developing Talented Soccer Players: An Analysis of Socio-Spatial Factors as Possible Key Constraints

PubMed Central

Pastor-Vicedo, Juan C.; González-Víllora, Sixto; Teoldo da Costa, Israel

2016-01-01

Abstract Most studies on the identification and development of soccer talent have been one-dimensional in nature. Although some multi-dimensional analyses have been conducted, few research studies have assessed in any depth the socio-spatial factors influencing talent development. The aim of this particular study was to analyse variations in the international representation of clubs (n = 821) and countries (n = 59) in the development of players who took part in the 2014 FIFA Soccer World Cup. Clubs and countries were ranked and divided into quartiles according to the number of players developed between the ages of 15 and 21 (clubs and countries that developed players for at least three years between these ages) and the number of official league matches played by these players up to the age of 23. Significant variations were observed between clubs in terms of the number of developed players who took part in the World Cup and the number of official league matches played by these players up to the age of 23 (p < .05), and also between countries (p < .05). The findings reveal the need to carry out more in-depth studies into the type of training and competition engaged in by elite players in the period of development between the ages of 15 and 21. It may be the case that these factors are potentially decisive socio-spatial constraints in the development of soccer talent. PMID:28031773

Days to Return to Participation After a Hamstrings Strain Among American Collegiate Soccer Players

PubMed Central

Cross, Kevin M.; Saliba, Susan A.; Conaway, Mark; Gurka, Kelly K.; Hertel, Jay

2015-01-01

Context Among US collegiate soccer players, the incidence rate and the event characteristics of hamstrings strains differ between sexes, but comparisons in the return-to-participation (RTP) time have not been reported. Objective To compare the RTP time between male and female collegiate soccer players and analyze the influence of event characteristics on the RTP time for each sex. Design Descriptive epidemiology study. Setting Data were collected from collegiate teams that voluntarily participated in the National Collegiate Athletic Association Injury Surveillance System. Patients or Other Participants Collegiate soccer athletes who sustained 507 hamstrings strains (306 men, 201 women) during the 2004 through 2009 fall seasons. Main Outcome Measure(s) Nonparametric statistics were used to evaluate RTP time differences between sexes and among categories of each event characteristic (ie, time of season, practice or competition, player position). Negative binomial regression was used to model the RTP time for each sex. All analyses were performed separately for first-time and recurrent strains. Results We found no differences in the RTP time between sexes for first-time (median: men = 7.0 days, women = 6.0 days; P = .07) or recurrent (median: men = 11 days, women = 5.5 days; P = .06) hamstrings strains. For male players with first-time strains, RTP time was increased when the strain occurred during competition or the in-season/postseason and varied depending on the division of play. Among female players with first-time strains, we found no differences in RTP time within characteristics. For male players with recurrent hamstrings strains, the RTP time was longer when the injury occurred during the in-season/postseason. Among female players with recurrent strains, RTP time was longer for forwards than for midfielders or defenders. Conclusions Although we found no differences in the RTP time after hamstrings strains in male and female collegiate soccer players, each sex

No Relationship Between Hamstring Flexibility and Hamstring Injuries in Male Amateur Soccer Players: A Prospective Study.

PubMed

van Doormaal, Mitchell C M; van der Horst, Nick; Backx, Frank J G; Smits, Dirk-Wouter; Huisstede, Bionka M A

2017-01-01

In soccer, although hamstring flexibility is thought to play a major role in preventing hamstring injuries, the relationship between hamstring flexibility and hamstring injuries remains unclear. To investigate the relationship between hamstring flexibility and hamstring injuries in male amateur soccer players. Case-control study; Level of evidence, 3. This study included 450 male first-class amateur soccer players (mean age, 24.5 years). Hamstring flexibility was measured by performing the sit-and-reach test (SRT). The relationship between hamstring flexibility and the occurrence of hamstring injuries in the following year, while adjusting for the possible confounding effects of age and previous hamstring injuries, was determined with a multivariate logistic regression analysis. Of the 450 soccer players, 21.8% reported a hamstring injury in the previous year. The mean (±SD) baseline score for the SRT was 21.2 ± 9.2 cm. During the 1-year follow-up period, 23 participants (5.1%) suffered a hamstring injury. In the multivariate analysis, while adjusting for age and previous injuries, no significant relationship was found between hamstring flexibility and hamstring injuries ( P = .493). In this group of soccer players, hamstring flexibility (measured with the SRT) was not related to hamstring injuries. Age and previous hamstring injuries as possible confounders did not appear to influence this relationship. Other etiological factors need to be examined to further elucidate the mechanism of hamstring injuries.

Post-match Perceived Exertion, Feeling and Wellness in Professional Soccer Players.

PubMed

Fessi, Mohamed Saifeddin; Moalla, Wassim

2018-01-18

The aim of this study was to assess post-match perceived exertion, feeling and wellness according to the match outcome (winning, drawing or losing) in professional soccer players. Twelve outfield players were followed during 52 official matches where the outcomes (win, draw or lose) were noted. Following each match players completed both a 10-point scale rating of perceived exertion (RPE) and an 11-point scale rating of perceived feeling. Rating of perceived sleep quality, stress, fatigue and muscle soreness were collected separately on a 7-point scale the day following each match. Player RPE was higher by a very largely magnitude following a loss compared to a draw or a win and higher by a small magnitude after a draw compared to a win. Players felt more pleasure after a win compared to a draw or loss and more displeasure after a loss compared to draw. The players reported a largely and moderately better-perceived sleep quality, less stress and fatigue following a win compared to draw or a loss, and a moderately bad-perceived sleep quality, higher stress and fatigue following a draw compared to a loss. In contrast, only a trivial-small change was observed in perceived muscle soreness between all outcomes. Matches outcomes moderately to largely affect RPE, perceived feeling, sleep quality, stress and fatigue whereas perceived muscle soreness remains high regardless of the match outcome. However, winning a match decreases the strain and improves both pleasure and wellness in professional soccer players.

The hypertrophy of the lateral abdominal wall and quadratus lumborum is sport-specific: an MRI segmental study in professional tennis and soccer players.

PubMed

Sanchis-Moysi, Joaquin; Idoate, Fernando; Izquierdo, Mikel; Calbet, Jose A; Dorado, Cecilia

2013-03-01

The aim was to determine the volume and degree of asymmetry of quadratus lumborum (QL), obliques, and transversus abdominis; the last two considered conjointly (OT), in tennis and soccer players. The volume of QL and OT was determined using magnetic resonance imaging in professional tennis and soccer players, and in non-active controls (n = 8, 14, and 6, respectively). In tennis players the hypertrophy of OT was limited to proximal segments (cephalic segments), while in soccer players it was similar along longitudinal axis. In tennis players the hypertrophy was asymmetric (18% greater volume in the non-dominant than in the dominant OT, p = 0.001), while in soccer players and controls both sides had similar volumes (p > 0.05). In controls, the non-dominant QL was 15% greater than that of the dominant (p = 0.049). Tennis and soccer players had similar volumes in both sides of QL. Tennis alters the dominant-to-non-dominant balance in the muscle volume of the lateral abdominal wall. In tennis the hypertrophy is limited to proximal segments and is greater in the non-dominant side. Soccer, however, is associated to a symmetric hypertrophy of the lateral abdominal wall. Tennis and soccer elicit an asymmetric hypertrophy of QL.

Importance of Muscle Power Variables in Repeated and Single Sprint Performance in Soccer Players

PubMed Central

López-Segovia, Manuel; Dellal, Alexandre; Chamari, Karim; González-Badillo, Juan José

2014-01-01

This study examined the relationship between lower body power and repeated as well as single sprint performance in soccer players. The performance of nineteen male soccer players was examined. The first testing session included the countermovement jump (CMJL) and the progressive full squat (FSL), both with external loads. Power in the CMJL and FSL was measured with each load that was lifted. The second session included a protocol of 40-m repeated sprints with a long recovery period (2 min). The number of sprints executed until there was a 3% decrease in performance for the best 40-m sprint time was recorded as a repeated sprint index (RSI). The RSI was moderately associated with power output relative to body mass in the CMJL and FSL (r = 0.53/0.54, p ≤ 0.05). The most and least powerful players (determined by FSL) showed significant differences in the RSI (9.1 ± 4.2 vs. 6.5 ± 1.6) and 10 m sprint time (p ± 0.01). Repeated and single sprints are associated with relatively lower body power in soccer players. PMID:25031688

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.

Peptide Glutamine Supplementation for Tolerance of Intermittent Exercise in Soccer Players

PubMed Central

Favano, Alessandra; Santos-Silva, Paulo Roberto; Nakano, Eduardo Yoshio; Pedrinelli, André; Hernandez, Arnaldo José; Greve, Julia Maria D’Andrea

2008-01-01

OBJECTIVE To investigate whether supplementation of carbohydrate together with peptide glutamine would increase exercise tolerance in soccer players. METHODS Nine male soccer players (mean age: 18.4 ± 1.1 years; body mass: 69.2 ± 4.6 kg; height: 175.5 ± 7.3 cm; and maximum oxygen consumption of 57.7 ± 4.8 ml·kg−1·min−1) were evaluated. All of them underwent a cardiopulmonary exercise test and followed a protocol that simulated the movements of a soccer game in order to evaluate their tolerance to intermittent exercise. By means of a draw, either carbohydrate with peptide glutamine (CARBOGLUT: 50g of maltodextrin + 3.5g of peptide glutamine in 250 ml of water) or carbohydrate alone (CARBO: 50g of maltodextrin in 250 ml of water) was administered in order to investigate the enhancement of the soccer players’ performances. The solution was given thirty minutes before beginning the test, which was performed twice with a one-week interval between tests. RESULTS A great improvement in the time and distance covered was observed when the athletes consumed the CARBOGLUT mixture. Total distance covered was 12750 ± 4037m when using CARBO, and 15571 ± 4184m when using CARBOGLUT (p<0.01); total duration of tolerance was 73 ± 23 min when using CARBO and 88 ± 24 min when using CARBOGLUT (p<0.01). CONCLUSION The CARBOGLUT mixture was more efficient in increasing the distance covered and the length of time for which intermittent exercise was tolerated. CARBOGLUT also reduced feelings of fatigue in the players compared with the use of the CARBO mixture alone. PMID:18297203

Are there differences in neurocognitive function and symptoms between male and female soccer players after concussions?

PubMed

Covassin, Tracey; Elbin, R J; Bleecker, Alisha; Lipchik, Adam; Kontos, Anthony P

2013-12-01

Researchers have suggested that there are sex differences in outcomes after sport-related concussions. Factors such as sport type/rules, age, and body mass index (BMI) may influence these differences. Hypotheses/ The purposes of this study were (1) to examine neurocognitive performance after concussions between male and female soccer players and (2) to compare concussion symptoms between male and female soccer players. We hypothesized that female concussed soccer players would report more concussion symptoms and worse cognitive performance compared with male concussed soccer players. Cohort study; Level of evidence, 2. A total of 39 male (mean BMI, 22.21 ± 2.34 kg/m(2); mean age, 17.69 ± 2.10 years) and 56 female (mean BMI, 23.47 ± 2.66 kg/m(2); mean age, 17.78 ± 2.30 years) concussed soccer players participated in this study. Participants were similar in age, history of concussion, sport, and time since injury. Participants completed computerized neurocognitive tests and symptom reports at baseline and 8 days after injury. Body mass index served as a covariate in all analyses. After adjusting for BMI, results from a repeated-measures analysis of covariance (ANCOVA) revealed a group by time interaction for visual memory (F1,82 = 5.50; P = .021). Specifically, female concussed soccer players (mean score, 68.7 ± 15.2) performed worse at 8 days after a concussion compared with male concussed athletes (mean score, 77.2 ± 8.9). Results of another ANCOVA for total concussion symptoms indicated an interaction for group by time (F1,82 = 4.26; P = .04). Specifically, female concussed soccer players (mean score, 11.9 ± 15.7) reported more total concussion symptoms at 8 days compared with male concussed athletes (mean score, 5.3 ± 7.4). There were significant main effects for sex on verbal (F1,82 = 5.98; P = .017) and visual (F1,82 = 4.65; P = .034) memory, with female athletes reporting lower scores than male athletes. Female athletes also reported more symptoms on

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.

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.

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.

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,…

Regular consumption of a flavanol-rich chocolate can improve oxidant stress in young soccer players.

PubMed

Fraga, Cesar G; Actis-Goretta, Lucas; Ottaviani, Javier I; Carrasquedo, Fernando; Lotito, Silvina B; Lazarus, Sheryl; Schmitz, Harold H; Keen, Carl L

2005-03-01

The consumption of a diet rich in certain flavonoids, including the flavanol sub-class, has been associated with a reduced risk for vascular disease. We evaluated the effects of the regular consumption (14 d) of a flavanol-containing milk chocolate (FCMC) or cocoa butter chocolate (CBC) on variables related to vascular disease risk, oxidative stress and physical activity. Twenty-eight free-living, young (18-20 years old) male soccer players consumed daily 105 g of FCMC (168 mg of flavanols) or CBC (< 5 mg of flavanols), as part of their normal diet. The consumption of FCMC was significantly associated with a decrease in diastolic blood pressure (- 5 mm Hg), mean blood pressure (- 5 mm Hg), plasma cholesterol (-11%), LDL-cholesterol (-15%), malondialdehyde (- 12%), urate (- 11%) and lactate dehydrogenase (LDH) activity (- 11%), and an increase in vitamin E/cholesterol (+ 12%). No relevant changes in these variables were associated with CBC consumption. No changes in the plasma levels of (-)-epicatechin were observed following analysis of fasting blood samples. In conclusion, FCMC consumption was associated with changes in several variables often associated with cardiovascular health and oxidant stress. The presence of significant quantities of flavanols in FCMC is likely to have been one of the contributing factors to these results.

Validity and Reliability of New Agility Test among Elite and Subelite under 14-Soccer Players

PubMed Central

Hachana, Younés; Chaabène, Helmi; Ben Rajeb, Ghada; Khlifa, Riadh; Aouadi, Ridha; Chamari, Karim; Gabbett, Tim J.

2014-01-01

Background Agility is a determinant component in soccer performance. This study aimed to evaluate the reliability and sensitivity of a “Modified Illinois change of direction test” (MICODT) in ninety-five U-14 soccer players. Methods A total of 95 U-14 soccer players (mean ± SD: age: 13.61±1.04 years; body mass: 30.52±4.54 kg; height: 1.57±0.1 m) from a professional and semi-professional soccer academy, participated to this study. Sixty of them took part in reliability analysis and thirty-two in sensitivity analysis. Results The intraclass correlation coefficient (ICC) that aims to assess relative reliability of the MICODT was of 0.99, and its standard error of measurement (SEM) for absolute reliability was <5% (1.24%). The MICODT’s capacity to detect change is “good”, it’s SEM (0.10 s) was ≤ SWC (0.33 s). The MICODT is significantly correlated to the Illinois change of direction speed test (ICODT) (r = 0.77; p<0.0001). The ICODT’s MDC95 (0.64 s) was twice about the MICODT’s MDC95 (0.28 s), indicating that MICODT presents better ability to detect true changes than ICODT. The MICODT provided good sensitivity since elite U-14 soccer players were better than non-elite one on MICODT (p = 0.005; dz = 1.01 [large]). This was supported by an area under the ROC curve of 0.77 (CI 95%, 0.59 to 0.89, p<0.0008). The difference observed in these two groups in ICODT was not statistically significant (p = 0.14; dz = 0.51 [small]), showing poor discriminant ability. Conclusion MICODT can be considered as more suitable protocol for assessing agility performance level than ICODT in U-14 soccer players. PMID:24752193

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

Internal and External Match Loads of University-Level Soccer Players: A Comparison Between Methods.

PubMed

Sparks, Martinique; Coetzee, Ben; Gabbett, Tim J

2017-04-01

Sparks, M, Coetzee, B, and Gabbett, TJ. Internal and external match loads of university-level soccer players: a comparison between methods. J Strength Cond Res 31(4): 1072-7077, 2017-The aim of this study was to use individualized intensity zones to compare the external (velocity and player load, PL) and internal loads (heart rate, HR) of a cohort of university-level soccer players. Thirteen soccer players completed a 40-m maximum speed test and the Yo-Yo intermittent recovery test 1 (Yo-Yo IR1) to determine individualized velocity and HR thresholds. Heart rate values and global positioning system (GPS) data of each player were recorded during 5 league matches. A large (r = 0.46; p ≤ 0.01) correlation was found between time spent in the low-intensity (LI) velocity zone (LIVZ) and the LI HR zone. Similarly, there were moderate (r = 0.25; p ≤ 0.01) to large (r = 0.57; p ≤ 0.01) correlations between the relative and absolute time spent in the moderate-intensity (MI) velocity zone (MIVZ) and the MI HR zone. No significant correlations (p ≤ 0.01) existed between the high-intensity (HI) velocity zones (HIVZ) and the HI HR zone. On the other hand, PL showed significant correlations with all velocity and HR (absolute and relative) variables, with the exception of a nonsignificant correlation between the HI HR variables and PL. To conclude, PL showed good correlations with both velocity and HR zones and therefore may have the potential to serve as a good indicator of both external and internal soccer match loads.

Ethnic Differences in Bony Hip Morphology in a Cohort of 445 Professional Male Soccer Players.

PubMed

Mosler, Andrea B; Crossley, Kay M; Waarsing, Jan H; Jomaah, Nabil; Weir, Adam; Hölmich, Per; Agricola, Rintje

2016-11-01

Participation in high-impact athletic activities has recently been associated with a higher prevalence of cam deformity. Bony hip morphology has also emerged as an important factor in the development of hip osteoarthritis. However, it is unknown whether bony morphology differs between ethnicities in athletes participating in high-impact sports. To investigate whether the prevalence of specific bony hip morphological abnormalities differed between professional male soccer players of diverse ethnic backgrounds. Cross-sectional study; Level of evidence, 3. Professional male soccer players from an entire league attending preparticipation screening were invited to participate in this study. Ethnicity was registered, and standardized radiographs of anteroposterior pelvic and Dunn views were obtained. Cam and pincer deformity, and acetabular dysplasia were quantified using the alpha angle, triangular index, and lateral center-edge angle (LCEA). Regression analyses with generalized estimating equations were used to determine prevalence differences in bony hip morphology. A total of 445 male soccer players (890 hips; mean age ± SD, 25 ± 4.9 years) participated in the study, representing the following ethnic groups: Arabic (59%), black (24%), Persian (7%), white (6%), East Asian (2%), and other (2%). The prevalence of cam deformity (alpha angle >60°) ranged from 57.5% to 71.7% across 4 of the groups, but East Asians had a significantly lower prevalence (18.8%; P ≤ .032). A large cam deformity (alpha angle >78°) was more prevalent in white (33.3%) compared with black soccer players (17.8%; P = .041) and was absent in East Asian players. Pincer deformity (LCEA >40°) was uncommon (3%) in all ethnicities. The prevalence of acetabular dysplasia (LCEA <20°) ranged from 8.0% to 16.7%, apart from the white group, in which prevalence was only 1.9% (P = .03). The prevalence of a cam deformity and acetabular dysplasia differed between ethnicities in this cohort of professional

Somatotype and body composition analysis of Korean youth soccer players according to playing position for sports physiotherapy research

PubMed Central

Noh, Ji-Woong; Kim, Mee-Young; Lee, Lim-Kyu; Park, Byoung-Sun; Yang, Seung-Min; Jeon, Hye-Joo; Lee, Won-Deok; Kim, Ju-Hyun; Lee, Jeong-Uk; Kwak, Taek-Yong; Lee, Tae-Hyun; Kim, Ju-Young; Kim, Junghwan

2015-01-01

[Purpose] The purpose of this study was to investigate the somatotype and physical characteristic differences among elite youth soccer players. [Subjects and Methods] In the present study, we evaluated twenty-two Korean youth soccer players in different playing positions. The playing positions were divided into forward (FW), midfielder (MF), defender (DF), and goalkeeper (GK). The participants’ lean body mass (LBM), fat free mass (FFM), fat mass (FM), and basal metabolic rate (BMR) were measured and their somatotype determined according to the Heath-Carter method. [Results] The youth soccer players had twelve ectomorphic, eight mesomorphic, and two central predominant types. The DFs were taller than, but otherwise similar in physical characteristics to the FWs and MFs. The GKs were taller and heavier than the other players; however, their somatotype components were not significantly different. LBM, FFM, and BMR were significantly higher in GKs than in FWs and MFs. Although LBM, FFM, and BMR values between GKs and DFs showed large differences, they were not statistically significant. [Conclusion] The present study may contribute to our understanding of the differences in somatotype and body composition of Korean youth soccer players involved in sports physiotherapy research. PMID:25995545

Somatotype and body composition analysis of Korean youth soccer players according to playing position for sports physiotherapy research.

PubMed

Noh, Ji-Woong; Kim, Mee-Young; Lee, Lim-Kyu; Park, Byoung-Sun; Yang, Seung-Min; Jeon, Hye-Joo; Lee, Won-Deok; Kim, Ju-Hyun; Lee, Jeong-Uk; Kwak, Taek-Yong; Lee, Tae-Hyun; Kim, Ju-Young; Kim, Junghwan

2015-04-01

[Purpose] The purpose of this study was to investigate the somatotype and physical characteristic differences among elite youth soccer players. [Subjects and Methods] In the present study, we evaluated twenty-two Korean youth soccer players in different playing positions. The playing positions were divided into forward (FW), midfielder (MF), defender (DF), and goalkeeper (GK). The participants' lean body mass (LBM), fat free mass (FFM), fat mass (FM), and basal metabolic rate (BMR) were measured and their somatotype determined according to the Heath-Carter method. [Results] The youth soccer players had twelve ectomorphic, eight mesomorphic, and two central predominant types. The DFs were taller than, but otherwise similar in physical characteristics to the FWs and MFs. The GKs were taller and heavier than the other players; however, their somatotype components were not significantly different. LBM, FFM, and BMR were significantly higher in GKs than in FWs and MFs. Although LBM, FFM, and BMR values between GKs and DFs showed large differences, they were not statistically significant. [Conclusion] The present study may contribute to our understanding of the differences in somatotype and body composition of Korean youth soccer players involved in sports physiotherapy research.

Gender differences in match performance characteristics of soccer players competing in the UEFA Champions League.

PubMed

Bradley, Paul S; Dellal, Alexandre; Mohr, Magni; Castellano, Julen; Wilkie, Anna

2014-02-01

The aim of this study was to examine gender differences in match performance characteristics of elite soccer players. Fifty-four male and fifty-nine female soccer players were tracked during UEFA Champions League matches using a multi-camera system (Amisco, Nice, France). Male players covered more (P<.01) distance than female players in total during a match (Effect Size [ES]: 0.5) and at higher speed thresholds (>15, >18, 18-21, 21-23, 23-25 and >27kmh(-1); ES: 0.7-1.4). Decrements in the second versus first half (P<.01) were only evident in female players for the distance covered in total and at selected speed thresholds (12-15, >12 and >15kmh(-1); ES: 0.6). Male central midfielders covered more (P<.01) total distance during a match than female central midfielders and at selected speed thresholds (15-23kmh(-1); ES: 1.3-2.2). Male full-backs and wide midfielders covered a greater distance (P<.01) than female players in the same positions at higher speed thresholds (>15, 21-23, 23-25, 25-27 and >27kmh(-1); ES: 1.5-3.1). The distance covered during the most intense 5min period of the match (>15kmh(-1)) was higher (P<.01) in male compared to female players (ES: 1.0) but no distance deficit in the next versus the average 5min period was observed for either gender (ES: 0.1-0.2). No gender differences were found for technical events such as the number of ball touches, time in possession of the ball or total duels won during both halves and the entire match (ES: 0.1-0.3). However, female players lost the ball more often (P<.05) and displayed lower pass completion rates than male players during both halves and the entire match (ES: 0.5-0.9). The data demonstrate that large gender differences exist for match performance characteristics of players competing at the highest competitive standard of European soccer. Such detailed analyses could be useful for gender-specific training information for optimal preparation. However, more research is warranted to establish gender

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).

Comparison of Two Kinds of Endurance Training Programs on the Effects of the Ability to Recover in Amateur Soccer Players

PubMed Central

Rogan, Slavko

2015-01-01

Background: High intensity intermittent aerobic exercise is an elementary endurance training exercise to build soccer endurance. Many studies exist with professional soccer players. But limited research has been conducted with amateur soccer players. Objectives: The aim of this study was to compare and assess the effects of the shuttle-run method and the Hoff-track method on the ability to recover in amateur soccer players within three weeks. Patients and Methods: Two amateur soccer teams were randomly assigned to shuttle-run group (n = 24; SRG) (SRG: shuttle-run group) or Hoff-track group (n = 18; HTG) (HTG: hoff-track group). They performed 2 times/week over three weeks their program. SRG performed a 20 m high speed shuttle-run until exhaustion and HTG covered at their highest speed level an obstacle track. Before and after training the yo-yo intermittent recovery test level 2 (YYIRTL2) was conducted. Results: Significant differences were observed within (P < 0.05) and between the groups (P = 0.06; ES = 0.50) in distance covering during YYIRTL2. Conclusions: Both training methods seem to improve the ability to recover in amateur soccer players within a short time period during the competition season. PMID:26448831

Characteristics of youth soccer players aged 13–15 years classified by skill level

PubMed Central

Malina, Robert M; Ribeiro, Basil; Aroso, João; Cumming, Sean P

2007-01-01

Objective To evaluate the growth, maturity status and functional capacity of youth soccer players grouped by level of skill. Subjects The sample included 69 male players aged 13.2–15.1 years from clubs that competed in the highest division for their age group. Methods Height and body mass of players were measured and stage of pubic hair (PH) was assessed at clinical examination. Years of experience in football were obtained at interview. Three tests of functional capacity were administered: dash, vertical jump and endurance shuttle run. Performances on six soccer‐specific tests were converted to a composite score which was used to classify players into quintiles of skill. Multiple analysis of covariance, controlling for age, was used to test differences among skill groups in experience, growth status and functional capacity, whereas multiple linear regression analysis was used to estimate the relative contributions of age, years of training in soccer, stage of PH, height, body mass, the height×weight interaction and functional capacities to the composite skill score. Results The skill groups differed significantly in the intermittent endurance run (p<0.05) but not in the other variables. Only the difference between the highest and lowest skill groups in the endurance shuttle run was significant. Most players in the highest (12 of 14) and high (11 of 14) skill groups were in stages PH 4 and PH 5. Pubertal status and height accounted for 21% of the variance in the skill score; adding aerobic resistance to the regression increased the variance in skill accounted for to 29%. In both regressions, the coefficient for height was negative. Conclusion Adolescent soccer players aged 13–15 years classified by skill do not differ in age, experience, body size, speed and power, but differ in aerobic endurance, specifically at the extremes of skill. Stage of puberty and aerobic resistance (positive coefficients) and height (negative coefficient) are significant

A four year prospective study of injuries in elite Ontario youth provincial and national soccer players during training and matchplay

PubMed Central

Mohib, Milad; Moser, Nicholas; Kim, Richard; Thillai, Maathavan; Gringmuth, Robert

2014-01-01

Introduction: With over 200 million amateur players worldwide, soccer is one of the most popular and internationally recognized sports today. By understanding how and why soccer injuries occur we hope to reduce prevalent injuries amongst elite soccer athletes. Methods: Via a prospective cohort, we examined both male and female soccer players eligible to train with the Ontario Soccer Association provincial program between the ages of 13 to 17 during the period of October 10, 2008 and April 20, 2012. Data collection occurred during all player exposures to potential injury. Exposures occurred at the Soccer Centre, Ontario Training grounds and various other venues on multiple playing surfaces. Results: A total number of 733 injuries were recorded. Muscle strain, pull or tightness was responsible for 45.6% of all injuries and ranked as the most prevalent injury. Discussion: As anticipated, the highest injury reported was muscular strain, which warrants more suitable preventive programs aimed at strengthening and properly warming up the players’ muscles. PMID:25550661

Caffeine-containing energy drink improves physical performance in female soccer players.

PubMed

Lara, Beatriz; Gonzalez-Millán, Cristina; Salinero, Juan Jose; Abian-Vicen, Javier; Areces, Francisco; Barbero-Alvarez, Jose Carlos; Muñoz, Víctor; Portillo, Luis Javier; Gonzalez-Rave, Jose Maria; Del Coso, Juan

2014-05-01

There is little information about the effects of caffeine intake on female team-sport performance. The aim of this study was to investigate the effectiveness of a caffeine-containing energy drink to improve physical performance in female soccer players during a simulated game. A double-blind, placebo controlled and randomized experimental design was used in this investigation. In two different sessions, 18 women soccer players ingested 3 mg of caffeine/kg in the form of an energy drink or an identical drink with no caffeine content (placebo). After 60 min, they performed a countermovement jump (CMJ) and a 7 × 30 m sprint test followed by a simulated soccer match (2 × 40 min). Individual running distance and speed were measured using GPS devices. In comparison to the placebo drink, the ingestion of the caffeinated energy drink increased the CMJ height (26.6 ± 4.0 vs 27.4 ± 3.8 cm; P < 0.05) and the average peak running speed during the sprint test (24.2 ± 1.6 vs 24.5 ± 1.7 km/h; P < 0.05). During the simulated match, the energy drink increased the total running distance (6,631 ± 1,618 vs 7,087 ± 1,501 m; P < 0.05), the number of sprints bouts (16 ± 9 vs 21 ± 13; P < 0.05) and the running distance covered at >18 km/h (161 ± 99 vs 216 ± 103 m; P < 0.05). The ingestion of the energy drink did not affect the prevalence of negative side effects after the game. An energy drink with a dose equivalent to 3 mg of caffeine/kg might be an effective ergogenic aid to improve physical performance in female soccer players.

Using Cartilage MRI T2-Mapping to Analyze Early Cartilage Degeneration in the Knee Joint of Young Professional Soccer Players.

PubMed

Waldenmeier, Leonie; Evers, Christoph; Uder, Michael; Janka, Rolf; Hennig, Frank Friedrich; Pachowsky, Milena Liese; Welsch, Götz Hannes

2018-02-01

Objective To evaluate and characterize the appearance of articular cartilage in the tibiofemoral joint of young professional soccer players using T2-relaxation time evaluation on magnetic resonance imaging (MRI). Design In this study, we included 57 male adolescents from the youth academy of a professional soccer team. The MRI scans were acquired of the knee joint of the supporting leg. An "early unloading" (minute 0) and "late unloading" (minute 28) T2-sequence was included in the set of images. Quantitative T2-analysis was performed in the femorotibial joint cartilage in 4 slices with each 10 regions of interest (ROIs). Statistical evaluation, using Wilcoxon signed-rank tests, was primarily performed to compare the T2 values of the "early unloading" and "late unloading." Results When comparing "early unloading" with "late unloading," our findings showed a significant increase of T2-relaxation times in the weightbearing femoral cartilage of the medial ( P < 0.001) and lateral ( P < 0.001) compartment of the knee and in the tibial cartilage of the medial compartment ( P < 0.001). Conclusion In this study, alterations of the cartilage were found with a maximum in the medial condyle where the biomechanical load of the knee joint is highest, as well as where most of the chronic cartilage lesions occur. To avoid chronic damage, special focus should be laid on this region.

Construct validity of tests that measure kick performance for young soccer players based on cluster analysis: exploring the relationship between coaches rating and actual measures.

PubMed

Palucci Vieira, Luiz H; de Andrade, Vitor L; Aquino, Rodrigo L; Moraes, Renato; Barbieri, Fabio A; Cunha, Sérgio A; Bedo, Bruno L; Santiago, Paulo R

2017-12-01

The main aim of this study was to verify the relationship between the classification of coaches and actual performance in field tests that measure the kicking performance in young soccer players, using the K-means clustering technique. Twenty-three U-14 players performed 8 tests to measure their kicking performance. Four experienced coaches provided a rating for each player as follows: 1: poor; 2: below average; 3: average; 4: very good; 5: excellent as related to three parameters (i.e. accuracy, power and ability to put spin on the ball). The scores interval established from k-means cluster metric was useful to originating five groups of performance level, since ANOVA revealed significant differences between clusters generated (P<0.01). Accuracy seems to be moderately predicted by the penalty kick, free kick, kicking the ball rolling and Wall Volley Test (0.44≤r≤0.56), while the ability to put spin on the ball can be measured by the free kick and the corner kick tests (0.52≤r≤0.61). Body measurements, age and PHV did not systematically influence the performance. The Wall Volley Test seems to be a good predictor of other tests. Five tests showed reasonable construct validity and can be used to predict the accuracy (penalty kick, free kick, kicking a rolling ball and Wall Volley Test) and ability to put spin on the ball (free kick and corner kick tests) when kicking in soccer. In contrast, the goal kick, kicking the ball when airborne and the vertical kick tests exhibited low power of discrimination and using them should be viewed with caution.

The Effects of Cupping on Hamstring Flexibility in Collegiate Soccer Players.

PubMed

Williams, Jeffrey G; Gard, Hannah I; Gregory, Jeana M; Gibson, Amy; Austin, Jennifer

2018-01-24

Collegiate soccer players suffer hamstring injuries due to inflexibility and repetitive motions involving intense hamstring lengthening and contraction during sport. Although a popular intervention for muscular injury, there exists limited evidence of the effects of therapeutic cupping on hamstring flexibility. To determine the effect of cupping therapy on hamstring flexibility in collegiate soccer players. Cohort design. Athletic training clinic. Twenty-five, asymptomatic, NCAA Division III soccer players (10 males, 15 females) (age = 19.4 ± 1.30 years, height = 175.1 ± 8.2 cm, mass = 69.5 ± 6.6 kg). A 7-minute therapeutic cupping treatment was delivered to the treatment group. Four 2-inch cups were fixed atop trigger point locations within the hamstring muscle bellies of participants' dominant legs. Control group participants received no intervention between pre- and post-test measurements. Pretest and posttest measurements of hamstring flexibility, using a Passive Straight Leg Raise (PSLR), were performed on both groups. PSLR measurements were conducted by blinded examiners using a digital inclinometer. An independent samples t-test was used to analyze changes in hamstring flexibility from pre- to post-treatment with p-values set a priori at 0.05. An independent samples t-test demonstrated no significant difference in change in hamstring flexibility between participants in the treatment group and those in the control group (t 23 = -.961, p = .35). The findings of this study demonstrated no statistically significant changes in hamstring flexibility following a cupping treatment.

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

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.

Speed and countermovement-jump characteristics of elite female soccer players, 1995-2010.

PubMed

Haugen, Thomas A; Tønnessen, Espen; Seiler, Stephen

2012-12-01

The purpose of this investigation was to compare sprint and countermovement-jump (CMJ) performance among female competitive soccer players as a function of performance level, field position, and age. In addition, the authors wanted to quantify the evolution of these physical characteristics among elite players over a 15-y period. 194 female elite players (22± 4.1 y, 63 ± 5.6 kg), including an Olympic winning squad, tested 40-m sprint with electronic timing and CMJ on a force platform at the Norwegian Olympic training center from 1995 to 2010. Moderate to large velocity differences across performance levels and positions were observed. National-team players were 2% faster than 1st-division players (P = .027, d = 0.5) and 5% faster than 2nd-division players (P < .001, d = 1.3) over 0-20 m. National-team players jumped 8-9% higher than 1st-division players (P = .001, d = 0.6) and junior elite players (P = .023, d = 0.5). Forwards were 3-4% faster than midfielders (P < .001, d = 0.8) and goalkeepers (P = .003, d = 0.9) over 0-20 m. No differences in velocity or CMJ height were observed among the age categories. Players from 2006-2010 were 2% faster (P < .05, d = 0.6) than players from 1995-1999 over 20 m, whereas no differences in 20- to 40-m velocity or CMJ performance were observed. This study provides effect-magnitude estimates for the influence of performance level, age, and player position on sprint and CMJ performance in female soccer players. While 20- to 40-m velocity and CMJ performance have remained stable over the time, there has been a moderate but positive development in 0- to 20-m velocity among elite performers.

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

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.

Physical performance characteristics of high-level female soccer players 12-21 years of age.

PubMed

Vescovi, J D; Rupf, R; Brown, T D; Marques, M C

2011-10-01

Performance assessment has become an invaluable component of monitoring player development and within talent identification programs in soccer, yet limited performance data are available for female soccer players across a wide age range. The aim of this study was to describe the physical performance characteristics of female soccer players ranging in age from 12 to 21 years. High-level female soccer players (n=414) were evaluated on linear sprinting (36.6 m with 9.1 m splits), countermovement jump (CMJ), and two agility tests. Separate one-way ANOVAs were used to compare performance characteristics between (1) each year of chronological age and (2) three age groups: 12-13 years, n=78, 14-17 years, n=223, and 18-21 years, n=113. Mean linear sprint speed over 9.1 m was similar across all chronological ages, however sprint speed over the final 9.1 m, CMJ height and agility scores improved until approximately 15-16 years. Outcomes from the group data indicated better performance on all tests for the 14-17-year-old group compared with the 12-13-year-old group. Additionally, sprint speed on the second and fourth 9.1 m splits and 36.6 m sprint speed as well as performance on the Illinois agility test was better in the 18-21-year-old group compared with the 14-17-year-old group. The findings from this study indicate that marked improvements of high intensity short duration work occur up until 15-16 years. Smaller gains in performance were observed beyond 16 years of age as evidenced by better performance on 36.6 m sprint speed, several sprint splits and the Illinois agility test in the college aged players (i.e., 18-21-year-old group). © 2010 John Wiley & Sons A/S.

Effect of Maturation on Hemodynamic and Autonomic Control Recovery Following Maximal Running Exercise in Highly Trained Young Soccer Players

PubMed Central

Buchheit, Martin; Al Haddad, Hani; Mendez-Villanueva, Alberto; Quod, Marc J.; Bourdon, Pitre C.

2011-01-01

The purpose of this study was to examine the effect of maturation on post-exercise hemodynamic and autonomic responses. Fifty-five highly trained young male soccer players (12–18 years) classified as pre-, circum-, or post-peak height velocity (PHV) performed a graded running test to exhaustion on a treadmill. Before (Pre) and after (5th–10th min, Post) exercise, heart rate (HR), stroke volume (SV), cardiac output (CO), arterial pressure (AP), and total peripheral resistance (TPR) were monitored. Parasympathetic (high frequency [HFRR] of HR variability (HRV) and baroreflex sensitivity [Ln BRS]) and sympathetic activity (low frequency [LFSAP] of systolic AP variability) were estimated. Post-exercise blood lactate [La]b, the HR recovery (HRR) time constant, and parasympathetic reactivation (time-varying HRV analysis) were assessed. In all three groups, exercise resulted in increased HR, CO, AP, and LFSAP (P < 0.001), decreased SV, HFRR, and Ln BRS (all P < 0.001), and no change in TPR (P = 0.98). There was no “maturation × time” interaction for any of the hemodynamic or autonomic variables (all P > 0.22). After exercise, pre-PHV players displayed lower SV, CO, and [La]b, faster HRR and greater parasympathetic reactivation compared with circum- and post-PHV players. Multiple regression analysis showed that lean muscle mass, [La]b, and Pre parasympathetic activity were the strongest predictors of HRR (r2 = 0.62, P < 0.001). While pre-PHV players displayed a faster HRR and greater post-exercise parasympathetic reactivation, maturation had little influence on the hemodynamic and autonomic responses following maximal running exercise. HRR relates to lean muscle mass, blood acidosis, and intrinsic parasympathetic function, with less evident impact of post-exercise autonomic function. PMID:22013423

Types of errors by referees and perception of injustice by soccer players: a preliminary study.

PubMed

Canovas, Sophie; Reynes, Eric; Ferrand, Claude; Pantaléon, Nathalie; Long, Thierry

2008-02-01

This study investigated the effect of referees' errors on players' perceived injustice in soccer. The conditions investigated were Referee Decision, with three types: Correctly Called a foul vs Wrongly Called a foul vs Did not Call a foul and Repetition of the Situation, with two types: Isolated vs Repeated. Male soccer players at regional and departmental levels of practice (N = 95, M(age) = 23.2, SD = 5.1) were asked to rank six hypothetical situations according to the perceived injustice. Analysis indicated significant effects of Referee Decisions and Repetition of the Situation on the perception of injustice, but showed no differences between the types of error. However, age and years of soccer experience were associated with perception of injustice when the referee correctly called a foul.

Repeated sprint ability related to recovery time in young soccer players.