Exercise-training intervention studies in competitive swimming.
Aspenes, Stian Thoresen; Karlsen, Trine
2012-06-01
Competitive swimming has a long history and is currently one of the largest Olympic sports, with 16 pool events. Several aspects separate swimming from most other sports such as (i) the prone position; (ii) simultaneous use of arms and legs for propulsion; (iii) water immersion (i.e. hydrostatic pressure on thorax and controlled respiration); (iv) propulsive forces that are applied against a fluctuant element; and (v) minimal influence of equipment on performance. Competitive swimmers are suggested to have specific anthropometrical features compared with other athletes, but are nevertheless dependent on physiological adaptations to enhance their performance. Swimmers thus engage in large volumes of training in the pool and on dry land. Strength training of various forms is widely used, and the energetic systems are addressed by aerobic and anaerobic swimming training. The aim of the current review was to report results from controlled exercise training trials within competitive swimming. From a structured literature search we found 17 controlled intervention studies that covered strength or resistance training, assisted sprint swimming, arms-only training, leg-kick training, respiratory muscle training, training the energy delivery systems and combined interventions across the aforementioned categories. Nine of the included studies were randomized controlled trials. Among the included studies we found indications that heavy strength training on dry land (one to five repetitions maximum with pull-downs for three sets with maximal effort in the concentric phase) or sprint swimming with resistance towards propulsion (maximal pushing with the arms against fixed points or pulling a perforated bowl) may be efficient for enhanced performance, and may also possibly have positive effects on stroke mechanics. The largest effect size (ES) on swimming performance was found in 50 m freestyle after a dry-land strength training regimen of maximum six repetitions across three sets in relevant muscle-groups (ES 1.05), and after a regimen of resisted- and assisted-sprint training with elastic surgical tubes (ES 1.21). Secondly, several studies suggest that high training volumes do not pose any immediate advantage over lower volumes (with higher intensity) for swim performance. Overall, very few studies were eligible for the current review although the search strategy was broad and fairly liberal. The included studies predominantly involved freestyle swimming and, overall, there seems to be more questions than answers within intervention-based competitive swimming research. We believe that this review may encourage other researchers to pursue the interesting topics within the physiology of competitive swimming.
Combined strength and endurance training in competitive swimmers.
Aspenes, Stian; Kjendlie, Per-Ludvik; Hoff, Jan; Helgerud, Jan
2009-01-01
A combined intervention of strength and endurance training is common practice in elite swimming training, but the scientific evidence is scarce. The influences between strength and endurance training have been investigated in other sports but the findings are scattered. Some state the interventions are negative to each other, some state there is no negative relationship and some find bisected and supplementary benefits from the combination when training is applied appropriately. The aim of this study was to investigate the impact of a combined intervention among competitive swimmers. 20 subjects assigned to a training intervention group (n = 11) or a control group (n = 9) from two different teams completed the study. Anthropometrical data, tethered swimming force, land strength, performance in 50m, 100m and 400m, work economy, peak oxygen uptake, stroke length and stroke rate were investigated in all subjects at pre- and post-test. A combined intervention of maximal strength and high aerobic intensity interval endurance training 2 sessions per week over 11 weeks in addition to regular training were used, while the control group continued regular practice with their respective teams. The intervention group improved land strength, tethered swimming force and 400m freestyle performance more than the control group. The improvement of the 400m was correlated with the improvement of tethered swimming force in the female part of the intervention group. No change occurred in stroke length, stroke rate, performance in 50m or 100m, swimming economy or peak oxygen uptake during swimming. Two weekly dry-land strength training sessions for 11 weeks increase tethered swimming force in competitive swimmers. This increment further improves middle distance swimming performance. 2 weekly sessions of high- intensity interval training does not improve peak oxygen uptake compared with other competitive swimmers. Key pointsTwo weekly sessions of dry land strength training improves the swimming force.Two weekly sessions of high-intensity endurance training did not cause improved endurance capacity.It may seem that dry land strength training can improve middle distance performance.
Physical and energy requirements of competitive swimming events.
Pyne, David B; Sharp, Rick L
2014-08-01
The aquatic sports competitions held during the summer Olympic Games include diving, open-water swimming, pool swimming, synchronized swimming, and water polo. Elite-level performance in each of these sports requires rigorous training and practice to develop the appropriate physiological, biomechanical, artistic, and strategic capabilities specific to each sport. Consequently, the daily training plans of these athletes are quite varied both between and within the sports. Common to all aquatic athletes, however, is that daily training and preparation consumes several hours and involves frequent periods of high-intensity exertion. Nutritional support for this high-level training is a critical element of the preparation of these athletes to ensure the energy and nutrient demands of the training and competition are met. In this article, we introduce the fundamental physical requirements of these sports and specifically explore the energetics of human locomotion in water. Subsequent articles in this issue explore the specific nutritional requirements of each aquatic sport. We hope that such exploration will provide a foundation for future investigation of the roles of optimal nutrition in optimizing performance in the aquatic sports.
Nugent, Frank J; Comyns, Thomas M; Warrington, Giles D
2017-06-01
The debate over low-volume, high-intensity training versus high-volume, low-intensity training, commonly known as Quality versus Quantity, respectively, is a frequent topic of discussion among swimming coaches and academics. The aim of this study was to explore expert coaches' perceptions of quality and quantity coaching philosophies in competitive swimming and to investigate their current training practices. A purposeful sample of 11 expert swimming coaches was recruited for this study. The study was a mixed methods design and involved each coach participating in 1 semi-structured interview and completing 1 closed-ended questionnaire. The main findings of this study were that coaches felt quality training programmes would lead to short term results for youth swimmers, but were in many cases more appropriate for senior swimmers. The coaches suggested that quantity training programmes built an aerobic base for youth swimmers, promoted technical development through a focus on slower swimming and helped to enhance recovery from training or competition. However, the coaches continuously suggested that quantity training programmes must be performed with good technique and they felt this was a misunderstood element. This study was a critical step towards gaining a richer and broader understanding on the debate over Quality versus Quantity training from an expert swimming coaches' perspective which was not currently available in the research literature.
Nugent, Frank J; Comyns, Thomas M; Warrington, Giles D
2017-01-01
Abstract The debate over low-volume, high-intensity training versus high-volume, low-intensity training, commonly known as Quality versus Quantity, respectively, is a frequent topic of discussion among swimming coaches and academics. The aim of this study was to explore expert coaches’ perceptions of quality and quantity coaching philosophies in competitive swimming and to investigate their current training practices. A purposeful sample of 11 expert swimming coaches was recruited for this study. The study was a mixed methods design and involved each coach participating in 1 semi-structured interview and completing 1 closed-ended questionnaire. The main findings of this study were that coaches felt quality training programmes would lead to short term results for youth swimmers, but were in many cases more appropriate for senior swimmers. The coaches suggested that quantity training programmes built an aerobic base for youth swimmers, promoted technical development through a focus on slower swimming and helped to enhance recovery from training or competition. However, the coaches continuously suggested that quantity training programmes must be performed with good technique and they felt this was a misunderstood element. This study was a critical step towards gaining a richer and broader understanding on the debate over Quality versus Quantity training from an expert swimming coaches’ perspective which was not currently available in the research literature. PMID:28713467
Buczkowska-Radlińska, J; Łagocka, R; Kaczmarek, W; Górski, M; Nowicka, A
2013-03-01
The purpose of this study was to analyze the prevalence of dental erosion among competitive swimmers of the local swimming club in Szczecin, Poland, who train in closely monitored gas-chlorinated swimming pool water. The population for this survey consisted of a group of junior competitive swimmers who had been training for an average of 7 years, a group of senior competitive swimmers who had been training for an average of 10 years, and a group of recreational swimmers. All subjects underwent a clinical dental examination and responded to a questionnaire regarding aspects of dental erosion. In pool water samples, the concentration of calcium, magnesium, phosphate, sodium, and potassium ions and pH were determined. The degree of hydroxyapatite saturation was also calculated. Dental erosion was found in more than 26 % of the competitive swimmers and 10 % of the recreational swimmers. The lesions in competitive swimmers were on both the labial and palatal surfaces of the anterior teeth, whereas erosions in recreational swimmers developed exclusively on the palatal surfaces. Although the pH of the pool water was neutral, it was undersaturated with respect to hydroxyapatite. The factors that increase the risk of dental erosion include the duration of swimming and the amount of training. An increased risk of erosion may be related to undersaturation of pool water with hydroxyapatite components. To decrease the risk of erosion in competitive swimmers, the degree of dental hydroxyapatite saturation should be a controlled parameter in pool water.
Kapus, Jernej; Usaj, Anton; Strumbelj, Boro; Kapus, Venceslav
2008-01-01
The aim of the present study was to ascertain whether maximal 200 m front crawl swimming strategies and breathing patterns influenced blood gas and acid-base parameters in a manner which gives advantage to former competitive swimmers in comparison with their recreational colleagues. Twelve former competitive male swimmers (the CS group) and nine recreational male swimmers (the RS group) performed a maximal 200 m front crawl swimming with self- selected breathing pattern. Stroke rate (SR) and breathing frequency (BF) were measured during the swimming test. Measures also included blood lactate concentration ([LA]) and parameters of blood acid-base status before and during the first minute after the swimming test. The CS group swam faster then the RS group. Both groups have similar and steady SR throughout the swimming test. This was not matched by similar BF in the CS group but matched it very well in the RS group (r = 0.89). At the beginning of swimming test the CS group had low BF, but they increased it throughout the swimming test. The BF at the RS group remained constant with only mirror variations throughout the swimming test. Such difference in velocity and breathing resulted in maintaining of blood Po2 from hypoxia and Pco2 from hypercapnia. This was similar in both groups. [LA] increased faster in the CS group than in the RS group. On the contrary, the rate of pH decrease remained similar in both groups. The former competitive swimmers showed three possible advantages in comparison to recreational swimmers during maximal 200 m front crawl swimming: a more dynamic and precise regulation of breathing, more powerful bicarbonate buffering system and better synchronization between breathing needs and breathing response during swimming. Key pointsTraining programs for competitive swimmers should promote adaptations to maximal efforts.Those adaptations should include high and maximal intensity swims with controlled breathing frequency (taking breath every fourth, fifth, sixth or eighth stroke cycle for front crawl swimming).Such training will improve breathing regulation in order to impose a better synchronization between breathing needs and breathing response during maximal swimming. PMID:24150142
ERIC Educational Resources Information Center
Flynn, Susan; Duell, Kelly; Dehaven, Carole; Heidorn, Brent
2017-01-01
The Kick, Stroke and Swim (KSS) program can be used to engage students in swimming-skill acquisition and fitness training using a variety of modalities, strategies and techniques on dry land. Practicing swim strokes and techniques on land gives all levels of swimmers--from beginner to competitive--a kinesthetic awareness of the individual…
Edmonds, Rohan
2015-01-01
The purpose of this study was to a) determine the heart rate variability (HRV) and saliva markers of immunity (salivary immunoglobulin A; sIgA) and stress (salivary alpha-amylase; sAA) responses to chronic training in elite swimmers with a disability; and b) identify the relationships between HRV, sIgA, sAA and training volume. Eight members of a high performance Paralympic swimming program were monitored for their weekly resting HRV, sIgA and sAA levels in the 14 weeks leading up to a major international competition. The 14 week training program included aerobic, anaerobic, power and speed, and taper training phases, while also incorporating two swimming step tests and two swimming competitions. Specific time (root mean square of the successive differences; RMSSD) and frequency (high frequency normalized units [HFnu]) domain measures, along with non-linear indices (standard deviation of instantaneous RR variability; SD1 and short term fractal scaling exponent; α1) of HRV were used for all analyses with effects examined using magnitude-based inferences. Relationships between HRV and saliva markers were identified by Spearman rank rho (ρ) correlation coefficients. Compared with week 1, SD1 was very likely lower (96/4/0, ES = -2.21), while sAA was very likely elevated (100/0/0, ES = 2.32) at the beginning of week 7 for all athletes. The training program did not alter HRV or saliva whereas competition did. There were also no apparent differences observed for HRV, sIgA and sAA between each of the training phases during the 14 week swimming program. Correlations were observed between sAA and SD1 (ρ = -0.212, p<0.05), along with sAA and mean HR (ρ = 0.309, p<0.05). These results show that high level national competition influences depresses HRV (SD1) and increases saliva biomarkers of stress (sAA). It appears that a well-managed and periodised swimming program can maintain these indices within normal baseline levels. The study also highlighted the parasympathetic nervous system influence on sAA. PMID:26043224
Edmonds, Rohan; Burkett, Brendan; Leicht, Anthony; McKean, Mark
2015-01-01
The purpose of this study was to a) determine the heart rate variability (HRV) and saliva markers of immunity (salivary immunoglobulin A; sIgA) and stress (salivary alpha-amylase; sAA) responses to chronic training in elite swimmers with a disability; and b) identify the relationships between HRV, sIgA, sAA and training volume. Eight members of a high performance Paralympic swimming program were monitored for their weekly resting HRV, sIgA and sAA levels in the 14 weeks leading up to a major international competition. The 14 week training program included aerobic, anaerobic, power and speed, and taper training phases, while also incorporating two swimming step tests and two swimming competitions. Specific time (root mean square of the successive differences; RMSSD) and frequency (high frequency normalized units [HFnu]) domain measures, along with non-linear indices (standard deviation of instantaneous RR variability; SD1 and short term fractal scaling exponent; α1) of HRV were used for all analyses with effects examined using magnitude-based inferences. Relationships between HRV and saliva markers were identified by Spearman rank rho (ρ) correlation coefficients. Compared with week 1, SD1 was very likely lower (96/4/0, ES = -2.21), while sAA was very likely elevated (100/0/0, ES = 2.32) at the beginning of week 7 for all athletes. The training program did not alter HRV or saliva whereas competition did. There were also no apparent differences observed for HRV, sIgA and sAA between each of the training phases during the 14 week swimming program. Correlations were observed between sAA and SD1 (ρ = -0.212, p<0.05), along with sAA and mean HR (ρ = 0.309, p<0.05). These results show that high level national competition influences depresses HRV (SD1) and increases saliva biomarkers of stress (sAA). It appears that a well-managed and periodised swimming program can maintain these indices within normal baseline levels. The study also highlighted the parasympathetic nervous system influence on sAA.
Sports Medicine Meets Synchronized Swimming.
ERIC Educational Resources Information Center
Wenz, Betty J.; And Others
This collection of articles contains information about synchronized swimming. Topics covered include general physiology and cardiovascular conditioning, flexibility exercises, body composition, strength training, nutrition, coach-athlete relationships, coping with competition stress and performance anxiety, and eye care. Chapters are included on…
Fluid dynamics of competitive swimming: An experimental study
NASA Astrophysics Data System (ADS)
Wei, T.; Voorhees, A.; Mark, R.; Mittal, R.
2004-11-01
The world of competitive swimming is dynamic. Swimmers today are bigger, stronger and faster than they ever have been. The training regimen of an elite athlete includes not only endless practice of his or her skills, but also a carefully planned diet, strength and endurance training, and hours of mental preparation. Within this framework, researchers from Rutgers and George Washington Universities have teamed with USA Swimming to develop advanced, fluid dynamics based training and analysis tools for current and future Olympic swimmers. The focus of this presentation will be on the objectives, methodologies and early outcomes of DPIV measurements of flow around swimmers. Testing was conducted at the Olympic training center in Colorado Springs and focussed specifically on the dolphin kick, an undulating motion swimmers use at the beginning of a race and after pushing off from the wall during a turn. Movies of flow measurements around swimmers, including Beth Botsford, the 1996 Olympic Gold Medalist in the 100 m backstroke, will be presented.
The Impact of Resistance Training on Swimming Performance: A Systematic Review.
Crowley, Emmet; Harrison, Andrew J; Lyons, Mark
2017-11-01
The majority of propulsive forces in swimming are produced from the upper body, with strong correlations between upper body strength and sprint performance. There are significant gaps in the literature relating to the impact of resistance training on swimming performance, specifically the transfer to swimming performance. The aims of this systematic literature review are to (1) explore the transfer of resistance-training modalities to swimming performance, and (2) examine the effects of resistance training on technical aspects of swimming. Four online databases were searched with the following inclusion criteria: (1) journal articles with outcome measures related to swimming performance, and (2) competitive swimmers participating in a structured resistance-training programme. Exclusion criteria were (1) participants with a mean age <16 years; (2) untrained, novice, masters and paraplegic swimmers; (3) triathletes and waterpolo players; (4) swimmers with injuries or illness; and (5) studies of starts and turns specifically. Data were extracted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, and the Physiotherapy Evidence Database (PEDro) scale was applied. For optimal transfer, specific, low-volume, high-velocity/force resistance-training programmes are optimal. Stroke length is best achieved through resistance training with low repetitions at a high velocity/force. Resisted swims are the most appropriate training modality for improving stroke rate. Future research is needed with respect to the effects of long-term resistance-training interventions on both technical parameters of swimming and overall swimming performance. The results of such work will be highly informative for the scientific community, coaches and athletes.
Boadas, A; Osorio, M; Gibraltar, A; Rosas, M M; Berges, A; Herrera, E; Gadea, S; Gutiérrez, M Á; Salazar, F; Ruiz-Sáez, A
2015-01-01
Swimming is beneficial for persons with haemophilia (PWH) providing good maintenance of the cardiovascular and musculoskeletal system and improving many psychological characteristics. In the Desafío del Caribe Project, young PWH from Venezuela and Mexico took part in an open water competition in the Gulf of Mexico under a multidisciplinary team supervision. Eight severe haemophilia A, two moderate haemophilia A, one severe haemophilia B and two moderate haemophilia B subjects were included. Haematological, musculoskeletal and psychological evaluations were carried out before and during training for the competition. Training program included physical exercise routines and swimming practices that alternated between pools and open water. Swimmers had coverage with factor concentrates before pool and open water trainings. In physiatric evaluations, the Hemophilia Joint Health Score (HJHS) was used. The objective of the psychology area was to analyse self-esteem, precompetition anxiety, coping mechanisms and relaxation levels. The need of factor prophylaxis before intense trainings was confirmed. In the musculoskeletal system a decrease of elbow pain as well as an increase of muscle strength in the ankles were observed. In the psychological area significant differences between the first and second test in self-esteem levels, cognitive anxiety and group cohesion were found. PWH must be provided with orientation and encouragement to practice swimming regularly. High competition exercise must be supervised by a multidisciplinary team which must evaluate the pros and cons of the activity to make relevant recommendations. © 2014 John Wiley & Sons Ltd.
Intra-abdominal pressure during swimming.
Moriyama, S; Ogita, F; Huang, Z; Kurobe, K; Nagira, A; Tanaka, T; Takahashi, H; Hirano, Y
2014-02-01
The present study aimed to determine the intra-abdominal pressure during front crawl swimming at different velocities in competitive swimmers and to clarify the relationships between stroke indices and changes in intra-abdominal pressure. The subjects were 7 highly trained competitive collegiate male swimmers. Intra-abdominal pressure was measured during front crawl swimming at 1.0, 1.2 and 1.4 m · s(-1) and during the Valsalva maneuver. Intra-abdominal pressure was taken as the difference between minimum and maximum values, and the mean of 6 stable front crawl stroke cycles was used. Stroke rate and stroke length were also measured as stroke indices. There were significant differences in stroke rate among all velocities (P < 0.05). However, there was no significant difference in stroke length by velocity. Significant within-subject correlations between intra-abdominal pressure and stroke rate or stroke length (P < 0.01) were observed, although there were no significant correlations between intra-abdominal pressure and stroke indices when controlling for swimming velocity. These findings do not appear to support the effectiveness of trunk training performed by competitive swimmers aimed at increasing intra-abdominal pressure. © Georg Thieme Verlag KG Stuttgart · New York.
Pelayo, P; Mujika, I; Sidney, M; Chatard, J C
1996-01-01
The purpose of this study was to relate measurements of blood lactate concentration, performance during a maximal anaerobic lactic test (MANLT) and training loads during a 23-week swimming season. Six elite 200-m freestyle male swimmers [mean age 19.5 (SD 1.6) years, height 184 (SD 5) cm and body mass 77.7 (SD 9.0) kg], participated in the study. The MANLT consisted of four all-out 50-m swims interspersed with 10-s recovery periods. Blood lactate concentrations were determined at 3 and 12-min post-exercise and were performed on weeks 2,6,10,14,18 and 21. Swimmers participated in 200-m freestyle competitions on weeks 1,7,13 and 23 (national championships). During weeks 1-10, training mostly involved aerobic exercise, while during weeks, 11-23, it involved anaerobic exercise. At 3-min and 12-min post-MANLT lactate concentrations varied throughout the season [range from 14.9 (SD 1.2) to 18.7 (SD 1.0) mmol.l-1] but demonstrated non-systematic variations. In contrast, the percentage of mean blood lactate decrease (% [La-]recovery) between min 3 and min 12 of the passive recovery post-MANLT increased from week 2 to 10 with aerobic training and decreased from week 10 to 21 with anaerobic training. The MANLT performance improved continuously throughout the season, while competition performance improved during the first three competitions but declined in the final championships, coinciding with the lowest % [La-]recovery and signs of overtraining, such as bad temper and increased sleeping heart rate. The results of this study indicated that % [La-]recovery could be an efficient marker for monitoring the impact of aerobic and anaerobic training and avoiding overtraining in elite 200-m swimmers.
Das, Pradip Kumar; Panja, Debjit
2013-12-01
Swimming is a mass-oriented, well organised and health directed sport which helps to acquire good health for the participants. In our country it is started mostly in the 8-9 years of age and when compared to developed countries the children start the practices around the 3-6 years of age. In swimming like other sports, injury can happen particularly during practice and events competition. The different types of injuries like shoulder joint injury, knee joint injury, red eyes, ear-nose infections, muscle cramps, etc, so happened during swimming practice and swimming competition, affect the performances of the swimmers on many different levels, in both training and in swim meets. This is an ongoing problem for many swimmers, moreover swimming is an intense workout, so it's important to make sure for getting adequate nutrition throughout the day. Proper nutrition and dieting play a large role in optimising swimming performance. A poor diet has a negative effect on athletic performance, as it is also evident in this study where most of the swimmers are suffering from nutritional anaemia as detected by the low level of haemoglobin in their blood and so today the study work has obviously thrown some light on this aspect to highlight the problems and their solutions.
Association Between Years of Competition and Shoulder Function in Collegiate Swimmers.
Dischler, Jack D; Baumer, Timothy G; Finkelstein, Evan; Siegal, Daniel S; Bey, Michael J
Shoulder injuries are common among competitive swimmers, and the progression of shoulder pathology is not well understood. The objective of this study was to assess the extent to which years of competitive swim training were associated with physical properties of the supraspinatus muscle and tendon, shoulder strength, and self-reported assessments of shoulder pain and function. Increasing years of competition will be associated with declining physical properties of the supraspinatus muscle/tendon and declining self-reported assessments of pain and function. Descriptive epidemiology study. Level 4. After institutional approval, 18 collegiate female swimmers enrolled in the study. For each swimmer, supraspinatus tendon thickness was measured; tendinosis was assessed using ultrasound imaging, supraspinatus muscle shear wave velocity was assessed using shear wave elastography, isometric shoulder strength was measured using a Biodex system, and self-reported assessments of pain/function were assessed using the Western Ontario Rotator Cuff (WORC) score. All subjects were tested before the start of the collegiate swim season. Linear regression was used to assess the association between years of competition and the outcome measures. Years of participation was positively associated with tendon thickness ( P = 0.01) and negatively associated with shear wave velocity ( P = 0.04) and WORC score ( P < 0.01). Shoulder strength was not associated with years of participation ( P > 0.39). Long-term competitive swim training is associated with declining measures of supraspinatus muscle/tendon properties and self-reported measures of pain and function. Although specific injury mechanisms are still not fully understood, these findings lend additional insight into the development of rotator cuff pathology in swimmers. Lengthy swimming careers may lead to a chronic condition of reduced mechanical properties in the supraspinatus muscle and tendon, thereby increasing the likelihood of rotator cuff pathology.
Briars, Graham L; Gordon, Gillian Suzanne; Lawrence, Andrew; Turner, Andrew; Perry, Sharon; Pillbrow, Dan; Walston, Florence Einstein; Molyneux, Paul
2017-01-01
To determine whether during-exercise rehydration improves swimming performance and whether sports drink or water have differential effects on performance. Randomised controlled multiple crossover trial. A UK competitive swimming club. 19 club-level competitive swimmers, median age (range) 13 (11-17) years. Subjects were scheduled to drink ad libitum commercial isotonic sports drink (3.9 g sugars and 0.13 g salt per 100 mL) or water (three sessions each) or no drink (six sessions) in the course of twelve 75 min training sessions, each of which was followed by a 30 min test set of ten 100 m maximum-effort freestyle sprints each starting at 3 min intervals. Times for the middle 50 m of each sprint measured using electronic timing equipment in a Federation Internationale de Natation (FINA)-compliant six-lane 25 m competition swimming pool. Software-generated individual random session order in sealed envelopes. Analysis subset of eight sessions randomly selected by software after data collection completed. Participants blind to drink allocation until session start. In the analysis data set of 1118 swims, there was no significant difference between swim times for drinking and not drinking nor between drinking water or a sports drink. Mean (SEM) 50 m time for no-drink swims was 38.077 (0.128) s and 38.105 (0.131) s for drink swims, p=0.701. Mean 50 m times were 38.031 (0.184) s for drinking sports drink and 38.182 (0.186) s for drinking water, p=0.073. Times after not drinking were 0.027 s faster than after drinking (95% CI 0.186 s faster to 0.113 s slower). Times after drinking sports drink were 0.151 s faster than after water (95% CI 0.309 s faster to 0.002 s slower). Mean (SEM) dehydration from exercise was 0.42 (0.11)%. Drinking water or sports drink over 105 min of sustained effort swimming training does not improve swimming performance. ISRCTN: 49860006.
IMMEDIATE EFFECTS OF DEEP TRUNK MUSCLE TRAINING ON SWIMMING START PERFORMANCE.
Iizuka, Satoshi; Imai, Atsushi; Koizumi, Keisuke; Okuno, Keisuke; Kaneoka, Koji
2016-12-01
In recent years, deep trunk muscle training has been adopted in various sports, including swimming. This is performed both in everyday training and as part of the warm-up routine before competitive races. It is suggested that trunk stabilization exercises are effective in preventing injury, and aid in improving performance. However, conclusive evidence of the same is yet to be obtained. The time of start phase of swimming is a factor that can significantly influence competition performance in a swimming race. If trunk stabilization exercises can provide instantaneous trunk stability, it is expected that they will lead to performance improvements in the start phase of swimming. The purpose of this study was to investigate the immediate effect of trunk stabilization exercises on the start phase in swimming. Intervention study. Nine elite male swimmers (mean age 20.2 ± 1.0 years; height 174.4 ± 3.5 cm; weight 68.9 ± 4.1 kg) performed the swimming start movement. The measurement variables studied included flying distance, and the time and velocity of subjects at hands' entry and on reaching five meters. Measurements were taken in trials immediately before and after the trunk stabilization exercises. A comparison between pre- and post-exercise measurements was assessed. The time to reach five meters (T 5m ) decreased significantly after trunk stabilization exercises, by 0.019 s (p = 0.02). Velocity at entry (V entry ) did not demonstrate significant change, while velocity at five meters (V 5m ) increased significantly after the exercises (p = 0.023). In addition, the speed reduction rate calculated from V entry and V 5m significantly decreased by 5.17% after the intervention (p = 0.036). Trunk stabilization exercises may help reduce the time from start to five meters in the start phase in swimming. The results support the hypothesis that these exercises may improve swimming performance. Level 3b.
Increased exhaled breath condensate 8-isoprostane after a swimming session in competitive swimmers.
Morissette, Mathieu C; Murray, Nicolas; Turmel, Julie; Milot, Julie; Boulet, Louis-Philippe; Bougault, Valérie
2016-08-01
This study aimed to evaluate the levels of 8-isoprostane (8-IsoP) in the airways of competitive swimmers at baseline and after a swimming session according to their airway responsiveness. Twenty-three swimmers and six lifeguards had a baseline spirometry and bronchoprovocative challenges. During a second visit, swimmers performed a usual swimming session while lifeguards stayed in the same pool environment for the same time period. Forced expiratory volume in one second (FEV1) was measured before and 5 min after the end of the session. Exhaled breath condensate (EBC) was sampled before and 10 min after the session and EBC 8-IsoP levels were analysed by enzyme immunoassay. Change in EBC 8-IsoP from baseline to post-swimming session was calculated. We observed no relationships between airway hyper-responsiveness and 8-IsoP values before or after swimming in swimmers. The levels of 8-IsoP were significantly higher after the training session (mean value 2.9, s = 0.5 pg mL(-1)) than at baseline (mean value 1.9, s = 0.4 pg mL(-1)) in swimmers only (p = .012). EBC 8-IsoP levels after the swimming session significantly correlated with the percent change in FEV1 after swimming. EBC 8-IsoP levels were increased after training in swimmers but not in lifeguards, suggesting that exercise-induced hyperpnoea in a chlorinated pool environment increases airways oxidative stress.
Volume vs. intensity in the training of competitive swimmers.
Faude, O; Meyer, T; Scharhag, J; Weins, F; Urhausen, A; Kindermann, W
2008-11-01
The present study aimed at comparing a high-volume, low-intensity vs. low-volume, high-intensity swim training. In a randomized cross-over design, 10 competitive swimmers performed two different 4-week training periods, each followed by an identical taper week. One training period was characterized by a high-training volume (HVT) whereas high-intensity training was prevalent during the other program (HIT). Before, after two and four weeks and after the taper week subjects performed psychometric and performance testing: profile of mood states (POMS), incremental swimming test (determination of individual anaerobic threshold, IAT), 100 m and 400 m. A small significant increase in IAT was observed after taper periods compared to pre-training (+ 0.01 m/s; p = 0.01). Maximal 100-m and 400-m times were not significantly affected by training. The POMS subscore of "vigor" decreased slightly after both training periods (p = 0.06). None of the investigated parameters showed a significant interaction between test-time and training type (p > 0.13). Nearly all (83 %) subjects swam personal best times during the 3 months after each training cycle. It is concluded that, for a period of 4 weeks, high-training volumes have no advantage compared to high-intensity training of lower volume.
The Effect of Intensity on 3-Dimensional Kinematics and Coordination in Front-Crawl Swimming.
de Jesus, Kelly; Sanders, Ross; de Jesus, Karla; Ribeiro, João; Figueiredo, Pedro; Vilas-Boas, João P; Fernandes, Ricardo J
2016-09-01
Coaches are often challenged to optimize swimmers' technique at different training and competition intensities, but 3-dimensional (3D) analysis has not been conducted for a wide range of training zones. To analyze front-crawl 3D kinematics and interlimb coordination from low to severe swimming intensities. Ten male swimmers performed a 200-m front crawl at 7 incrementally increasing paces until exhaustion (0.05-m/s increments and 30-s intervals), with images from 2 cycles in each step (at the 25- and 175-m laps) being recorded by 2 surface and 4 underwater video cameras. Metabolic anaerobic threshold (AnT) was also assessed using the lactate-concentration-velocity curve-modeling method. Stroke frequency increased, stroke length decreased, hand and foot speed increased, and the index of interlimb coordination increased (within a catch-up mode) from low to severe intensities (P ≤ .05) and within the 200-m steps performed above the AnT (at or closer to the 4th step; P ≤ .05). Concurrently, intracyclic velocity variations and propelling efficiency remained similar between and within swimming intensities (P > .05). Swimming intensity has a significant impact on swimmers' segmental kinematics and interlimb coordination, with modifications being more evident after the point when AnT is reached. As competitive swimming events are conducted at high intensities (in which anaerobic metabolism becomes more prevalent), coaches should implement specific training series that lead swimmers to adapt their technique to the task constraints that exist in nonhomeostatic race conditions.
Influence of short-term inertial training on swimming performance in young swimmers.
Naczk, Mariusz; Lopacinski, Artur; Brzenczek-Owczarzak, Wioletta; Arlet, Jarosław; Naczk, Alicja; Adach, Zdzisław
2017-05-01
The aim of this study was to evaluate the influence of dry-land inertial training (IT) on muscle force, muscle power, and swimming performance. Fourteen young, national-level, competitive swimmers were randomly divided into IT and control (C) groups. The experiment lasted four weeks, during which time both groups underwent their regular swimming training. In addition, the IT group underwent IT using the Inertial Training Measurement System (ITMS) three times per week. The muscle groups involved during the upsweep phase of the arm stroke in front crawl and butterfly stroke were trained. Before and after training, muscle force and power were measured under IT conditions. Simultaneously with the biomechanical measurements on the ITMS, the electrical activity of the triceps brachii was registered. After four weeks of training, a 12.8% increase in the muscle force and 14.2% increase in the muscle power (p < .05) were noted in the IT group. Moreover, electromyography amplitude of triceps brachii recorded during strength measurements increased by 22.7% in the IT group. Moreover, swimming velocity in the 100 m butterfly and 50 m freestyle improved significantly following the four weeks of dry-land IT (-1.86% and -0.76%, respectively). Changes in the C group were trivial. Moreover, values of force and power registered during the ITMS test correlated negatively with the 100 m butterfly and 50 m freestyle swimming times (r value ranged from -.80 to -.91). These results suggest that IT can be useful in swimming practice.
Detraining increases body fat and weight and decreases VO2peak and metabolic rate.
Ormsbee, Michael J; Arciero, Paul J
2012-08-01
Competitive collegiate swimmers commonly take a month off from swim training after their last major competition. This abrupt cessation of intense physical training has not been well studied and may lead to physiopsychological decline. The purpose of this investigation was to examine the effects of swim detraining (DT) on body composition, aerobic fitness, resting metabolism, mood state, and blood lipids in collegiate swimmers. Eight healthy endurance-trained swimmers (V(O2)peak, 46.7 ± 10.8 ml · kg(-1) · min(-1)) performed 2 identical test days, 1 in the trained (TR) state and 1 in the detrained (~5 weeks) state (DT). Body composition and circumferences, maximal oxygen consumption (V(O2)peak), resting metabolism (RMR), blood lipids, and mood state were measured. After DT, body weight (TR, 68.9 ± 9.7 vs. DT, 69.8 ± 9.8 kg; p = 0.03), fat mass (TR, 14.7 ± 7.6 vs. DT, 16.5 ± 7.4 kg; p = 0.001), and waist circumference (TR, 72.7 ± 3.1 vs. DT, 73.8 ± 3.6 cm; p = 0.03) increased, whereas V(O2)peak (TR, 46.7 ± 10.8 vs. DT, 43.1 ± 10.3 ml · kg(-1) · min(-1); p = 0.02) and RMR (TR, 1.34 ± 0.2 vs. DT, 1.25 ± 0.17 kcal · min(-1); p = 0.008) decreased, and plasma triglycerides showed a trend to increase (p = 0.065). Our data suggest that DT after a competitive collegiate swim season adversely affects body composition, fitness, and metabolism. Athletes and coaches need to be aware of the negative consequences of detraining from swimming, and plan off-season training schedules accordingly to allow for adequate rest/recovery and prevent overuse injuries. It's equally important to mitigate the negative effects on body composition, aerobic fitness and metabolism so performance may continue to improve over the long term.
Clemente-Suárez, Vicente Javier; Dalamitros, Athanasios; Ribeiro, João; Sousa, Ana; Fernandes, Ricardo J; Vilas-Boas, J Paulo
2017-05-01
This study analysed the effects of two different periodization strategies on physiological parameters at various exercise intensities in competitive swimmers. Seventeen athletes of both sexes were divided to two groups, the traditional periodization (TPG, n = 7) and the reverse periodization group (RPG, n = 10). Each group followed a 10-week training period based on the two different periodization strategies. Before and after training, swimming velocity (SV), energy expenditure (EE), energy cost (EC) and percentage of aerobic (%Aer) and anaerobic (%An) energy contribution to the swimming intensities corresponding to the aerobic threshold (AerT), the anaerobic threshold (AnT) and the velocity at maximal oxygen uptake (vVO 2 max) were measured. Both groups increased the %An at the AerT and AnT intensity (P ≤ .05). In contrast, at the AnT intensity, EE and EC were only increased in TPG. Complementary, %Aer, %An, EE and EC at vVO 2 max did not alter in both groups (P > .05); no changes were observed in SV in TPG and RPG at all three intensities. These results indicate that both periodization schemes confer almost analogous adaptations in specific physiological parameters in competitive swimmers. However, given the large difference in the total training volume between the two groups, it is suggested that the implementation of the reverse periodization model is an effective and time-efficient strategy to improve performance mainly for swimming events where the AnT is an important performance indicator.
Applied physiology of triathlon.
O'Toole, M L; Douglas, P S
1995-04-01
The triathlon is a 3-event endurance sport in which athletes compete sequentially in swimming, cycling and running. The primary determinant of success is the ability to sustain a high rate of energy expenditure for prolonged periods of time. Exercise training-induced physiological adaptations in virtually all systems of the body allow the athlete to accomplish this. Aerobic capacity (measured as maximal oxygen uptake, VO2max), economy of motion (submaximal VO2) and fractional utilisation of maximal capacity (%VO2max) reflect the integrated responses of these physiological adaptations. Numerous studies have reported relatively high mean VO2max values for various groups of triathletes that are comparable to those reported for athletes in single-event endurance sports and clearly above those reported for untrained individuals. In shorter distance triathlons and in studies using recreational (rather than elite) triathletes, VO2max is related to performance in the corresponding event of the triathlon (e.g. tethered swimming VO2max with swim time). In longer events and with more elite triathletes, VO2max correlates less well with performance. The physiological adaptations that correspond to and facilitate improved VO2max occur centrally in the cardiovascular system, centred on increased maximal cardiac output, and peripherally in the metabolic systems, centred around increased arterio-venous O2 (a-v O2) difference. While a high VO2max in individuals is clearly of importance to triathlon performance, energy output must be sustained for long periods of time, making economy of motion also very important. Studies suggests that competitive swimmers have better swimming economy than triathletes. However, since many triathletes have previously been competitive swimmers this finding is questionable. The finding suggests that triathletes from nonswimming backgrounds would benefit from improving swimming technique rather than concentrating training workouts solely on distance. In cycling and running, comparison studies have not been done. Economy of motion in swimming, cycling and running have all been found to be correlated with comparable event performance. Training to improve swimming economy can be done without prior exercise, but training to improve swimming economy can be done without prior exercise, but training to improve cycling and running economy should take the multimode nature of a triathlon into consideration. That is, swimming should precede cycling economy training, and cycling should precede running economy training. Cardiovascular, metabolic and neuromuscular adaptations are the main physiological correlates of improved movement economy. Since exercise-induced stress on most physiological systems is based on relative, rather than absolute, exercise intensity, training and racing intensities are frequently quantified as a percentage of maximal capacity of %VO2max.(ABSTRACT TRUNCATED AT 400 WORDS)
Madsen, Pernille H; Bak, Klaus; Jensen, Susanne; Welter, Ulrik
2011-03-01
Scapular dyskinesis is a major etiological factor in overhead athletes' shoulder problems. Our hypotheses were to evaluate if (1) visual observation of scapular dyskinesis during scaption has substantial interobserver reliability, and (2) scapular dyskinesis may be induced by swim training in pain-free swimmers. A reliability and observational study. Bachelor project at a college institution and at a private sports orthopedic hospital. Seventy-eight competitive swimmers with no history of shoulder pain were included in the study. Fourteen swimmers were evaluated regarding reliability. Inclusion criteria were competitive swimmers with high training volume who previously had no shoulder pain. Observations of scapular dyskinesis (yes/no) during simple scaption. The interobserver reliability of scaption and wall push-up was evaluated in 14 swimmers using kappa analysis. Prevalence of scapular dyskinesis at 4 time intervals during a swim training session. The scaption test resulted in a weighted kappa value of 0.75. Scapular dyskinesis was seen in 29 shoulders (37%) after the first time interval, in another 24 (cumulated prevalence 68%) after one-half of the training session, and in an additional 4 swimmers (cumulated prevalence 73%) after three-quarters of the training session. During the last quarter of the training session, another 7 swimmers had dyskinesis, resulting in a cumulated prevalence of 82%. The prevalence of abnormal scapular kinesis during a normal training session is high in previously pain-free swimmers. The prevalence increases with more training and occurs early during the training session.
ERIC Educational Resources Information Center
Zauner, Christian W.; Benson, Norma Y.
This investigation sought to determine whether the excellent performer evolves from typical material through training or if he brings facilitating characteristics with him to practice on the first day. Subjects were highly successful AAU age-group competitors who had invested at least 50 percent of their lives in swim training. These seven female…
Immune cell changes in response to a swimming training session during a 24-h recovery period.
Morgado, José P; Monteiro, Cristina P; Teles, Júlia; Reis, Joana F; Matias, Catarina; Seixas, Maria T; Alvim, Marta G; Bourbon, Mafalda; Laires, Maria J; Alves, Francisco
2016-05-01
Understanding the impact of training sessions on the immune response is crucial for the adequate periodization of training, to prevent both a negative influence on health and a performance impairment of the athlete. This study evaluated acute systemic immune cell changes in response to an actual swimming session, during a 24-h recovery period, controlling for sex, menstrual cycle phases, maturity, and age group. Competitive swimmers (30 females, 15 ± 1.3 years old; and 35 males, 16.5 ± 2.1 years old) performed a high-intensity training session. Blood samples were collected before, immediately after, 2 h after, and 24 h after exercise. Standard procedures for the assessment of leukogram by automated counting (Coulter LH 750, Beckman) and lymphocytes subsets by flow cytometry (FACS Calibur BD, Biosciences) were used. Subjects were grouped according to competitive age groups and pubertal Tanner stages. Menstrual cycle phase was monitored. The training session induced neutrophilia, lymphopenia, and a low eosinophil count, lasting for at least 2 h, independent of sex and maturity. At 24 h postexercise, the acquired immunity of juniors (15-17 years old), expressed by total lymphocytes and total T lymphocytes (CD3(+)), was not fully recovered. This should be accounted for when planning a weekly training program. The observed lymphopenia suggests a lower immune surveillance at the end of the session that may depress the immunity of athletes, highlighting the need for extra care when athletes are exposed to aggressive environmental agents such as swimming pools.
Low dose creatine supplementation enhances sprint phase of 400 meters swimming performance.
Anomasiri, Wilai; Sanguanrungsirikul, Sompol; Saichandee, Pisut
2004-09-01
This study demonstrated the effect of low dose creatine supplement (10 g. per day) on the sprinting time in the last 50 meters of 400 meters swimming competition, as well as the effect on exertion. Nineteen swimmers in the experimental group received creatine monohydrate 5 g with orange solution 15 g, twice per day for 7 days and nineteen swimmers in the control group received the same quantity of orange solution. The results showed that the swimmers who received creatine supplement lessened the sprinting time in the last 50 meters of 400 meters swimming competition than the control group. (p<0.05). The results of Wingate test (anaerobic power, anaerobic capacity and fatigue index) compared between pre and post supplementation. There was significant difference at p<0.05 in the control group from training effect whereas there was significant difference at p<0.000 from training effect and creatine supplement in the experiment group. Therefore, the creatine supplement in amateur swimmers in the present study enhanced the physical performance up to the maximum capacity.
Main, Luana C; Warmington, Stuart A; Korn, Emily; Gastin, Paul B
2016-01-01
The purpose of the present study was to determine the efficacy of the multi-component training distress scale (MTDS), in monitoring swimmers prior to national competition. Twenty-one national-level adolescent swimmers completed eight weeks of testing. Once a week participants completed an 8 × 50 m sprint test, vertical jump test, sit-and-reach test, the MTDS and the Recovery-Stress Questionnaire for Athletes (REST-Q). All testing was incorporated into the swimmers' normal training programme. The REST-Q accounted for the following variances in performance: flexibility (14.6%, p = 0.009), power output (17.7%, p = 0.003), swimming speed (15.5%, p = 0.006) and swimming endurance (17.5%, p = 0.002). In comparison, the MTDS accounted for the following variances in performance: flexibility (12.1%, p = 0.095), power output (16.4%, p = 0.023), swimming speed (20.5%, p = 0.003) and swimming speed endurance (23.8%, p = 0.001). The findings of the current study suggest that both the REST-Q Sport and the MTDS have the capacity to predict performance on a range of fitness components associated with swimming.
Wilk, Robert; Karpiński, Jakub; Chalimoniuk, Małgorzata; Zajac, Adam; Langfort, Józef
2017-01-01
The main objective of this research was to evaluate the efficacy of intermittent hypoxic training (IHT) on anaerobic and aerobic capacity and swimming performance in well-trained swimmers. Sixteen male swimmers were randomly divided into a hypoxia (H) group (n = 8), which trained in a normobaric hypoxia environment, and a control (C) group (n = 8), which exercised under normoxic conditions. However, one participant left the study without explanation. During the experiment group H trained on land twice per week in simulated hypoxia (FiO2 = 15.5%, corresponding to 2,500 m a.s.l); however, they conducted swim training in normoxic conditions. Group C performed the same training program under normoxic conditions. The training program included four weekly microcyles, followed by three days of recovery. During practice sessions on land, the swimmers performed 30 second sprints on an arm-ergometer, alternating with two minute high intensity intervals on a lower limb cycle ergometer. The results showed that the training on land caused a significant (p<0.05) increase in absolute maximal workload (WRmax) by 7.4% in group H and by 3.2% in group C and relative values of VO2max by 6.9% in group H and 3.7% in group C. However, absolute values of VO2max were not significantly changed. Additionally, a significant (p<0.05) increase in mean power (Pmean) during the first (11.7%) and second (11.9%) Wingate tests was only observed in group H. The delta values of lactate concentration (ΔLA) after both Wingate tests were significantly (p<0.05) higher in comparison to baseline levels by 28.8% in group H. Opposite changes were observed in delta values of blood pH (ΔpH) after both Wingate tests in group H, with a significant decrease in values of ΔpH by 33.3%. The IHT caused a significant (p<0.05) improvement in 100m and 200m swimming performance, by 2.1% and 1.8%, respectively in group H. Training in normoxia (group C), resulted in a significant (p<0.05) improvement of swimming performance at 100m and 200m, by 1.1% and 0.8%, respectively. In conclusion, the most important finding of this study includes a significant improvement in anaerobic capacity and swimming performance after high-intensity IHT. However, this training protocol had no effect on absolute values of VO2max and hematological variables. PMID:28763443
Competitive Swimming and Racial Disparities in Drowning
Myers, Samuel L.; Cuesta, Ana M.; Lai, Yufeng
2018-01-01
This paper provides compelling evidence of an inverse relationship between competitive swimming rates and drowning rates using Centers for Disease Control and Prevention (CDC) data on fatal drowning rates and membership rates from USA Swimming, the governing organization of competitive swimming in the United States. Tobit and Poisson regression models are estimated using panel data by state from 1999–2007 separately for males, females, African Americans and whites. The strong inverse relationship between competitive swimming rates and unintentional deaths through fatal drowning is most pronounced among African Americans males.
Krahenbuhl, Tathyane; Gonçalves, Ezequiel M; Guimarães, Roseane Fatima; Guerra-Junior, Gil; Barros-Filho, Antonio
2016-08-01
To examine the influence of participation in competitive sports on bone parameters, as assessed by quantitative ultrasound (QUS) of the phalanges in female adolescents. Female adolescents (n = 329, 13.0-16.7 years old) were classified into handball (n = 55), swimming (n = 49) and control (n = 225) groups. QUS was used to evaluate the amplitude-dependent speed of sound (AD-SoS) and bone transmission time (BTT), and their z-scores (zAD-SoS and zBTT) were calculated. Anthropometric measurements and Tanner's stages were also obtained. Swimmers had higher AD-SoS (2089 ± 43.8 m/s) and zAD-SoS (0.47 ± 0.8) than controls (2060 ± 54.0 m/s; 0.09 ± 1.0; both p ≤ .05) and both groups of athletes had higher BTT (handball: 1.44 ± 0.2 μs; swimming: 1.45 ± 0.2) and zBTT (handball: 0.71 ± 0.8; swimming: 0.72 ± 1.1) than the control group (1.37 ± 0.2 μs; 0.32 ± 0.9; all p ≤ .05). Swimmers had a higher total training time (TTT: 52.5 ± 27.6 months) and frequency of training per week (FT: 5.38 ± 0.1) compared with the handball group (35.9 ± 18.1; 3.32 ± 0.8; p ≤ .05). zAD-SoS, BTT and zBTT were positively correlated with FT, while BTT and zBTT showed a positive correlation with TTT. Sports practice influences bone parameters and higher bone parameter values are related to the amount of time and frequency of weekly training. The differences in phalangeal QUS parameters are independent of the impact of weight-bearing exercise.
Hellard, Philippe; Scordia, Charlotte; Avalos, Marta; Mujika, Inigo; Pyne, David B
2017-10-01
Periodization of swim training in the final training phases prior to competition and its effect on performance have been poorly described. We modeled the relationships between the final 11 weeks of training and competition performance in 138 elite sprint, middle-distance, and long-distance swimmers over 20 competitive seasons. Total training load (TTL), strength training (ST), and low- to medium-intensity and high-intensity training variables were monitored. Training loads were scaled as a percentage of the maximal volume measured at each intensity level. Four training periods (meso-cycles) were defined: the taper (weeks 1 to 2 before competition), short-term (weeks 3 to 5), medium-term (weeks 6 to 8), and long-term (weeks 9 to 11). Mixed-effects models were used to analyze the association between training loads in each training meso-cycle and end-of-season major competition performance. For sprinters, a 10% increase between ∼20% and 70% of the TTL in medium- and long-term meso-cycles was associated with 0.07 s and 0.20 s faster performance in the 50 m and 100 m events, respectively (p < 0.01). For middle-distance swimmers, a higher TTL in short-, medium-, and long-term training yielded faster competition performance (e.g., a 10% increase in TTL was associated with improvements of 0.1-1.0 s in 200 m events and 0.3-1.6 s in 400 m freestyle, p < 0.01). For sprinters, a 60%-70% maximal ST load 6-8 weeks before competition induced the largest positive effects on performance (p < 0.01). An increase in TTL during the medium- and long-term preparation (6-11 weeks to competition) was associated with improved performance. Periodization plans should be adapted to the specialty of swimmers.
Devan, Bryan D; Tobin, Elizabeth L; Dunn, Emily N; Magalis, Christopher
2016-11-01
This study investigated sex differences on the competitive place version of the Morris water maze task to determine whether potential strategy differences would emerge during any phase of the study but in particular on the competitive place phase. Previous findings indicate that this version of the task is highly sensitive to measures that disrupt NMDA-dependent synaptic plasticity within the hippocampus during memory consolidation (McDonald et al., 2005). The present findings revealed significant sex differences during all phases of the study, including Phase I with standard place training to located a hidden platform/goal, Phase II mass training to a new place with the platform/goal relocated to the diagonally opposite quadrant and Phase III, competitive place probe test with the platform removed to measure spatial behaviour directed at either location. The findings showed no sex difference in escape latency and other standard performance measures during the first two phases, initial place acquisition and mass training to a new location. A very subtle male advantage in visiting both Old and New place locations during the third phase place competition test was observed, however, in the time spent swimming in the periphery of the pool, the pool wall (Zone C - outer third radial distance) was increased for females during all phases of the study, suggesting a general effect may have influenced place location search behaviour of the females. Increased peripheral pool time may represent a female preference for approaching the wall, a local cue. Alternatively, the possibility that increased peripheral swimming/thigmotaxis may represent hormonal influences interacting with strategic preferences were discussed, though no definitive conclusions about sex differences in cognitive-spatial performance or memory consolidation were inferred from the present findings. The findings suggest that mixed results reported in the literature by others may be due in part to an interaction with a persistent peripheral pool swimming response demonstrated in female rats. Copyright © 2016 Elsevier B.V. All rights reserved.
Applications of neural networks in training science.
Pfeiffer, Mark; Hohmann, Andreas
2012-04-01
Training science views itself as an integrated and applied science, developing practical measures founded on scientific method. Therefore, it demands consideration of a wide spectrum of approaches and methods. Especially in the field of competitive sports, research questions are usually located in complex environments, so that mainly field studies are drawn upon to obtain broad external validity. Here, the interrelations between different variables or variable sets are mostly of a nonlinear character. In these cases, methods like neural networks, e.g., the pattern recognizing methods of Self-Organizing Kohonen Feature Maps or similar instruments to identify interactions might be successfully applied to analyze data. Following on from a classification of data analysis methods in training-science research, the aim of the contribution is to give examples of varied sports in which network approaches can be effectually used in training science. First, two examples are given in which neural networks are employed for pattern recognition. While one investigation deals with the detection of sporting talent in swimming, the other is located in game sports research, identifying tactical patterns in team handball. The third and last example shows how an artificial neural network can be used to predict competitive performance in swimming. Copyright © 2011 Elsevier B.V. All rights reserved.
Nagle Zera, Jacquelyn; Nagle, Elizabeth F; Nagai, Takashi; Lovalekar, Mita; Abt, John P; Lephart, Scott M
2018-02-14
The purpose of this study was three-fold: (a) to examine the test-retest reliability of a 30 second maximal tethered freestyle swimming test (TST), (b) to assess the validity of the TST by examining the association to sprint swimming performance and, (c) to examine the associations between a swim-specific and land-based measure of anaerobic performance. A total of twenty-nine male and female swimmers were recruited to participate in the study. Each participant completed a Wingate Anaerobic cycling test (WAnT), two or four TST, and a 22.9 meter (25 yard), 45.7 meter (50 yard), and 91.4 meter (100 yard) maximal freestyle performance swims (PS). Mean and peak force (Fmean, Fpeak) were recorded for both the WAnT and TST, and average swimming velocity and time were recorded for the PS. Additionally, physiological and perceptual measures were recorded immediate post exercise for all tests. The results of the present investigation showed strong intersession and intrasession reliability (R= 0.821-0.975; p<0.001) for force parameters of the TST. Moderate correlations were found between Fmean and PS time and velocity of all distances, with slightly weaker correlations between Fpeak and the 22.9 meter (time and velocity) and 45.7 meter (velocity) PS. Finally, moderate correlations were found for Fmean and Fpeak of the TST and WAnT. This study demonstrated that the TST is a reliable measure, with moderate association to swimming performance, producing similar physiological responses compared to free swimming. Therefore, future research shoulSd focus on investigating the potential benefits of utilizing the TST as a regular assessment tool as a part of a competitive swimming training program to track adaptations and inform training decisions.
Heart rate variability and swimming.
Koenig, Julian; Jarczok, Marc N; Wasner, Mieke; Hillecke, Thomas K; Thayer, Julian F
2014-10-01
Professionals in the domain of swimming have a strong interest in implementing research methods in evaluating and improving training methods to maximize athletic performance and competitive outcome. Heart rate variability (HRV) has gained attention in research on sport and exercise to assess autonomic nervous system activity underlying physical activity and sports performance. Studies on swimming and HRV are rare. This review aims to summarize the current evidence on the application of HRV in swimming research and draws implications for future research. A systematic search of databases (PubMed via MEDLINE, PSYNDEX and Embase) according to the PRISMA statement was employed. Studies were screened for eligibility on inclusion criteria: (a) empirical investigation (HRV) in humans (non-clinical); (b) related to swimming; (c) peer-reviewed journal; and (d) English language. The search revealed 194 studies (duplicates removed), of which the abstract was screened for eligibility. Fourteen studies meeting the inclusion criteria were included in the review. Included studies broadly fell into three classes: (1) control group designs to investigate between-subject differences (i.e. swimmers vs. non-swimmers, swimmers vs. other athletes); (2) repeated measures designs on within-subject differences of interventional studies measuring HRV to address different modalities of training or recovery; and (3) other studies, on the agreement of HRV with other measures. The feasibility and possibilities of HRV within this particular field of application are well documented within the existing literature. Future studies, focusing on translational approaches that transfer current evidence in general practice (i.e. training of athletes) are needed.
Stellingwerff, Trent; Maughan, Ronald J; Burke, Louise M
2011-01-01
Contemporary training for power sports involves diverse routines that place a wide array of physiological demands on the athlete. This requires a multi-faceted nutritional strategy to support both general training needs--tailored to specific training phases--as well as the acute demands of competition. Elite power sport athletes have high training intensities and volumes for most of the training season, so energy intake must be sufficient to support recovery and adaptation. Low pre-exercise muscle glycogen reduces high-intensity performance, so daily carbohydrate intake must be emphasized throughout training and competition phases. There is strong evidence to suggest that the timing, type, and amount of protein intake influence post-exercise recovery and adaptation. Most power sports feature demanding competition schedules, which require aggressive nutritional recovery strategies to optimize muscle glycogen resynthesis. Various power sports have different optimum body compositions and body weight requirements, but increasing the power-to-weight ratio during the championship season can lead to significant performance benefits for most athletes. Both intra- and extracellular buffering agents may enhance performance, but more research is needed to examine the potential long-term impact of buffering agents on training adaptation. Interactions between training, desired physiological adaptations, competition, and nutrition require an individual approach and should be continuously adjusted and adapted.
Effects of sodium bicarbonate ingestion on swim performance in youth athletes
Zajac, Adam; Cholewa, Jaroslaw; Poprzecki, Stanislaw; Waskiewicz, Zbigniew; Langfort, Jozef
2009-01-01
The purpose of this study was to evaluate the effect of oral administration of sodium bicarbonate (300 mg·kg-1 b.w.) on swim performance in competitive, (training experience of 6.6 ± 0.6 years) youth, (15.1 ± 0.6 years) male swimmers. The subjects completed a test trial, in a double blind fashion, on separate days, consisting of 4 x 50m front crawl swims with a 1st minute passive rest interval twice, on two occasions: after ingestion of bicarbonate or placebo, 72 hours apart, at the same time of the day. Blood samples were drawn from the finger tip three times during each trial; upon arrival to the laboratory, 60 min after ingestion of placebo or the sodium bicarbonate solution and after the 4 x 50m test, during the 1st min of recovery. Plasma lactate concentration, blood pH, standard bicarbonate and base excess were evaluated. The total time of the 4 x 50 m test trial improved from 1.54.28 to 1.52.85s, while statistically significant changes in swimming speed were recorded only during the first 50m sprint (1.92 vs. 1.97 m·s-1, p < 0.05). Resting blood concentration of HCO-3 increased following the ingestion of sodium bicarbonate from 25.13 to 28.49 mM (p < 0.05). Sodium bicarbonate intake had a statistically significant effect on resting blood pH (7.33 vs. 7.41, p < .05) as well as on post exercise plasma lactate concentration (11.27 vs. 13.06 mM, p < 0.05)). Collectively, these data demonstrate that the ingestion of sodium bicarbonate in youth athletes is an effective buffer during high intensity interval swimming and suggest that such a procedure can be used in youth athletes to increase training intensity as well as swimming performance in competition at distances from 50 to 200 m. Key points Sodium bicarbonate is an effective ergogenic aid, also in youth athletes. Sodium bicarbonate intake improves swimming sprint performance. Sodium bicarbonate intake increases resting blood pH and bicarbonate level PMID:24150555
Blood lactate accumulation in top level swimmers following competition.
Bonifazi, M; Martelli, G; Marugo, L; Sardella, F; Carli, G
1993-03-01
The purposes of this study were to evaluate the significance of blood lactate values after competitions and the blood lactate-swimming speed relationship to swimming performances. Auricular blood samples (N = 421) were collected in 203 top level Italian swimmers (116 males and 87 females) at the end of competitions performed in a 25 m swimming pool. The distribution of all lactate values differed between males and females. The lowest lactate values occurred in swimmers performing the longest distances both in males (1500 m) and females (800 m). In swimmers performing freestyle events a relationship between V-4 mM (swimming speed at 4 mmol/l blood lactate value) and competition velocities was observed, in males, at 200, 400 and 1500 m and, in females, at 400 and 800 m. The predicted velocity corresponding to the competition lactate value assessed by the individual blood lactate-swimming speed relationship was found to be highly related to the actual competition velocity. Results suggest that blood lactate values in swimmers are a useful indication of individual aptitudes.
Characteristics and Challenges of Open-Water Swimming Performance: A Review.
Baldassarre, Roberto; Bonifazi, Marco; Zamparo, Paola; Piacentini, Maria Francesca
2017-11-01
Although the popularity of open-water swimming (OWS) events has significantly increased in the last decades, specific studies regarding performance of elite or age-group athletes in these events are scarce. To analyze the existing literature on OWS. Relevant literature was located via computer-generated citations. During August 2016, online computer searches on PubMed and Scopus databases were conducted to locate published research. The number of participants in ultraendurance swimming events has substantially increased in the last 10 y. In elite athletes there is a higher overall competitive level of women than of men. The body composition of female athletes (different percentage and distribution of fat tissue) shows several advantages (more buoyancy and less drag) in aquatic conditions that determine the small difference between males and females. The main physiological characteristics of open-water swimmers (OW swimmers) are the ability to swim at high percentage of [Formula: see text] (80-90%) for many hours. Furthermore, to sustain high velocity for many hours, endurance swimmers need a high propelling efficiency and a low energy cost. Open-water races may be characterized by extreme environmental conditions (water temperature, tides, currents, and waves) that have an overall impact on performance, influencing tactics and pacing. Future studies are needed to study OWS in both training and competition.
Swimmers' compliance with training prescription.
Stewart, A M; Hopkins, W G
1997-10-01
The purpose of this study was to determine how closely competitive swimmers complied with their coaches' prescriptions when training in squads. A training session early in the buildup phase of the season was observed for each of 24 coaches who had been randomized to two groups: an experimental, high-intensity, low-distance program (E) and a control (usual) program (C). Swim distances, rest durations, and swim durations for at least one set of prescribed repetitions (reps) were recorded for each of 47 swimmers (87 sets, 429 reps) in E and for 49 swimmers (79 sets, 402 reps) in C. The pace of each rep, expressed as percent of the swimmer's current personal best pace for the distance of the rep, represented observed intensity. There was almost perfect agreement between the prescribed and observed swim distances for the set of reps (Spearman r = 0.99 in both groups). Prescribed and observed rest intervals were also closely matched in E and C (Spearman r = 0.87 and 0.77 respectively). Four coaches in E and 10 coaches in C prescribed intensity subjectively as easy, moderate, hard, or race-pace; mean +/- SD observed intensities (%) for their swimmers were 79 +/- 6, 81 +/- 3, 91 +/- 2, and 93 +/- 5, respectively. The relationship between these coaches' subjective training prescription and individual swimmers' interpretations of these intensities was poor (Cohen's kappa = 0.39). Nine coaches in E prescribed intensity as percent of personal best pace. Although the mean prescribed and observed intensities for their swimmers were similar (89 +/- 4 and 90 +/- 7, respectively), the relationship between individual values was poor (Pearson r = 0.30). We conclude that swimmers complied with prescribed distances and rest intervals but were less effective in judging the intensity of swim training. We recommend that coaches monitor training intensity more closely.
Smith, H K; Montpetit, R R; Perrault, H
1988-01-01
Few studies have examined the aerobic demand of backstroke swimming, and its relation to body morphology, technique, or performance. The aims of this study were thus to: i) describe the aerobic demand of backstroke swimming in proficient swimmers at high velocities; ii) assess the effects of body size and stroke technique on submaximal and maximal O2 costs, and; iii) test for a relationship between submaximal O2 costs and maximal performance. Sixteen male competitive swimmers were tested during backstroke swimming at velocities from 1.0 to 1.4 m.s-1. Results showed that VO2 increased linearly with velocity (m.s-1) following the equation VO2 = 6.28v - 3.81 (r = 0.77, SEE/Y = 14.9%). VO2 was also related to the subjects' body mass, height, and armspan. Longer distances per stroke were associated with lower O2 costs, and better maximal performances. A significant relation was found between VO2 at 1.1 m.s-1, adjusted for body mass, and 400 m performance (r = -0.78). Submaximal VO2 was also related to reported times for 100 m and 200 m races. Multiple correlation analyses indicated that VO2 at 1.1 m.s-1 and VO2max accounted for up to 78% of the variance in maximal performances. These results suggest that the assessment of submaximal and maximal VO2 during backstroke swimming may be of value in the training and testing programs of competitive swimmers.
Gabrilo, Goran; Peric, Mia; Stipic, Marija
2011-03-01
Pulmonary function (PF) is particularly important in synchronized swimming, considering the characteristics of this sport. However, the sanitizing agents (chlorine) used in pools can have a possible negative influence on the PF parameters. In this study, we observed 24 swimmers (all women, 14 to 16 years of age) and measured their PF and competitive achievement. PF was measured before and after a 1-year period and included standard spirometric variables. Competitive achievement was evidenced during the National Championship. The t-test showed significant increases in body height and weight of the participants and a resulting increase in most of the absolute respiratory flows and pulmonary capacities. Forced vital capacity (FVC) and forced expiratory volume (both in proportion to norm for body height, gender, and age) increased significantly within the study period. FVC significantly predicted the competitive achievement of young swimmers, most probably because artists have to achieve exceptional breath control when upside down underwater. In conclusion, we found no evidence for the eventual negative influence of chlorine and its compounds on the PF of swimmers, and results showed that regular synchronized swim training could improve the PF of young artists.
Zinner, Christoph; Heilemann, Ilka; Kjendlie, Per-Ludvik; Holmberg, Hans-Christer; Mester, Joachim
2010-01-01
Training volume in swimming is usually very high when compared to the relatively short competition time. High-intensity interval training (HIIT) has been demonstrated to improve performance in a relatively short training period. The main purpose of the present study was to examine the effects of a 5-week HIIT versus high-volume training (HVT) in 9–11-year-old swimmers on competition performance, 100 and 2,000 m time (T100 m and T2,000 m), VO2peak and rate of maximal lactate accumulation (Lacmax). In a 5-week crossover study, 26 competitive swimmers with a mean (SD) age of 11.5 ± 1.4 years performed a training period of HIIT and HVT. Competition (P < 0.01; effect size = 0.48) and T2,000 m (P = 0.04; effect size = 0.21) performance increased following HIIT. No changes were found in T100 m (P = 0.20). Lacmax increased following HIIT (P < 0.01; effect size = 0.43) and decreased after HVT (P < 0.01; effect size = 0.51). VO2peak increased following both interventions (P < 0.05; effect sizes = 0.46–0.57). The increases in competition performance, T2,000 m, Lacmax and VO2peak following HIIT were achieved in significantly less training time (~2 h/week). PMID:20683609
Nutrition considerations for open-water swimming.
Shaw, Gregory; Koivisto, Anu; Gerrard, David; Burke, Louise M
2014-08-01
Open-water swimming (OWS) is a rapidly developing discipline. Events of 5-25 km are featured at FINA World Championships, and the international circuit includes races of 5-88 km. The Olympic OWS event, introduced in 2008, is contested over 10 km. Differing venues present changing environmental conditions, including water and ambient temperatures, humidity, solar radiation, and unpredictable tides. Furthermore, the duration of most OWS events (1-6 hr) creates unique physiological challenges to thermoregulation, hydration status, and muscle fuel stores. Current nutrition recommendations for open-water training and competition are either an extension of recommendations from pool swimming or are extrapolated from other athletic populations with similar physiological requirements. Competition nutrition should focus on optimizing prerace hydration and glycogen stores. Although swimmers should rely on self-supplied fuel and fluid sources for shorter events, for races of 10 km or greater, fluid and fuel replacement can occur from feeding pontoons when tactically appropriate. Over the longer races, feeding pontoons should be used to achieve desirable targets of up to 90 g/ hr of carbohydrates from multitransportable sources. Exposure to variable water and ambient temperatures will play a significant role in determining race nutrition strategies. For example, in extreme environments, thermoregulation may be assisted by manipulating the temperature of the ingested fluids. Swimmers are encouraged to work with nutrition experts to develop effective and efficient strategies that enhance performance through appropriate in-competition nutrition.
Profile of injures prevalence in athletes who participated in SESC Triathlon Caiobá-2011
Bertola, Izabela Pichinin; Sartori, Renato Pineda; Corrêa, Daniela Gallon; Zotz, Talita Gianello Gnoato; Gomes, Anna Raquel Silveira
2014-01-01
OBJECTIVE: To identify the prevalence of injuries occurred during training and/or competition in triathlon athletes at SESC Triathlon Caiobá-2011. METHODS: One hundred and ninety athletes participated in the study (153 males and 37 females). RESULTS: Athletes reported time of practice between 3 to 6 years (20%), training frequency of 5 days per week (48%), at least one injury during trainings (76%). The prevalence of injuries according to the sports category was: running (79%), cycling (16%) and swimming (5%). The most injured region during training (39%) and competition (46%) was the calf. Female athletes reported 92% of injuries during running training and 35% of those injuries were on ankle and foot. During competition only two athletes reported injuries. Muscle injury was the most prevalent (54%) among male athletes, followed by tendon (19%), ligament (17%) and bone (9%) injuries. Among female athletes prevalent injuries were: 32% muscle, 32% bone, 32% tendon and only 4% ligament injuries. CONCLUSION: Skeletal muscle injuries were the most commom lesions during running training, however, male athletes reported mostly calf injuries, while female had mostly ankle and foot injuries. Level of Evidence III. Study of Non-Consecutive Patients; Without Consistently Applied Reference ''Gold'' Standard. PMID:25246848
Critical evaluation of oxygen-uptake assessment in swimming.
Sousa, Ana; Figueiredo, Pedro; Pendergast, David; Kjendlie, Per-Ludvik; Vilas-Boas, João P; Fernandes, Ricardo J
2014-03-01
Swimming has become an important area of sport science research since the 1970s, with the bioenergetic factors assuming a fundamental performance-influencing role. The purpose of this study was to conduct a critical evaluation of the literature concerning oxygen-uptake (VO2) assessment in swimming, by describing the equipment and methods used and emphasizing the recent works conducted in ecological conditions. Particularly in swimming, due to the inherent technical constraints imposed by swimming in a water environment, assessment of VO2max was not accomplished until the 1960s. Later, the development of automated portable measurement devices allowed VO2max to be assessed more easily, even in ecological swimming conditions, but few studies have been conducted in swimming-pool conditions with portable breath-by-breath telemetric systems. An inverse relationship exists between the velocity corresponding to VO2max and the time a swimmer can sustain it at this velocity. The energy cost of swimming varies according to its association with velocity variability. As, in the end, the supply of oxygen (whose limitation may be due to central-O2 delivery and transportation to the working muscles-or peripheral factors-O2 diffusion and utilization in the muscles) is one of the critical factors that determine swimming performance, VO2 kinetics and its maximal values are critical in understanding swimmers' behavior in competition and to develop efficient training programs.
Influence of swimsuit design and fabric surface properties on the butterfly kinematics.
Rogowski, Isabelle; Monteil, Karine; Legreneur, Pierre; Lanteri, Pierre
2006-02-01
This study investigated the influence of the covering swimsuit and the fabric surface properties on the butterfly stroke kinematics. Surface properties were evaluated by wetting measurements of two fabric samples: one for training suits and one for competition suits. The surface of the second one was coated by mechanochemical treatment in order to modify its surface properties. Nine national level swimmers performed a 50-m butterfly at submaximal velocity in three swimsuit conditions: conventional, long, and coated long swimsuits. From video recording, the hip was digitized at the entry and exit of the swimmer's hand in order to calculate the duration, hip displacement, and hip linear velocity during underwater and recovery phases and during stroke. The results for wetting show that competition fabric was more water-repellent than training fabric, but both were isotropic. Moreover, the mechanochemical treatment increased water repellency and anisotropy. The swimming results indicated that, when compared to a conventional swimsuit, wearing a coated long swimsuit increased hip linear velocity during stroke, and particularly during the recovery phase which had a shorter duration. These results suggest that the covering swimsuit should be coupled with the water repellent and anisotropic properties of the fabric surface in order to improve swimming performance.
Collard, L; Oboeuf, A
2009-04-01
Underwater undulatory swimming (UUS) is often perceived to be a nonessential aspect of aquatic propulsion. Given their solid theoretical and practical training in swimming, physical education students should be capable of judging the true value of the "fifth stroke," since it appears to be the most efficient technique in high level, competitive swimming. To compare opinions and connotations associated with the stroke and the four official strokes (butterfly, backstroke, breaststroke, and crawl), 198 students (32 of whom were expert swimmers; M age = 20.6 yr., SD = 1.2), were surveyed using the semantic differential of Osgood, Suci, and Tannenbaum. Although answers of expert and nonexpert swimmers differed significantly (p < .01, except for the breaststroke), participants considered overall that undulatory stroke was less attractive, less powerful, and less rapid than the four surface strokes (d = 2.88 for the expert swimmers). Putting one arm in front of the other and repeating the sequence still remains the most solidly held representation of "the right way" to swim. However, the high observed standard deviations for the underwater undulatory stimulus (SD > or = 1.1 with SD max = 3 for the expert swimmers) attests to the view being less strongly held by swimming specialists.
McKenzie, Thomas L.; Rushall, Brent S.
1974-01-01
Swimmers' attendance at training and work rates were described by their coaches as being poor and irregular. Reinforcement contingencies were developed to remedy these unsatisfactory conditions. Two experiments were conducted. A multiple baseline design verified the effects of publicly marking attendance at practice as a sufficient solution for reducing absenteeism, tardiness, and leaving early. Follow-up analyses showed this contingency to have lasting effects. In the second experiment, a reversal design was used to assess the effects of employing program boards as a means of increasing work output during practice. Work rates in eight selected swimmers were elevated by an average of 27.1% when the boards were instituted. Follow-up evaluations showed that the use of the program boards had lasting effects. Publicly checking the completion of each training unit of work changed the nature of the swimming environment to produce a more productive use of time. The role of the coach was subsequently changed as less time was spent in directing and supervising behaviors. PMID:4436167
McKenzie, T L; Rushall, B S
1974-01-01
Swimmers' attendance at training and work rates were described by their coaches as being poor and irregular. Reinforcement contingencies were developed to remedy these unsatisfactory conditions. Two experiments were conducted. A multiple baseline design verified the effects of publicly marking attendance at practice as a sufficient solution for reducing absenteeism, tardiness, and leaving early. Follow-up analyses showed this contingency to have lasting effects. In the second experiment, a reversal design was used to assess the effects of employing program boards as a means of increasing work output during practice. Work rates in eight selected swimmers were elevated by an average of 27.1% when the boards were instituted. Follow-up evaluations showed that the use of the program boards had lasting effects. Publicly checking the completion of each training unit of work changed the nature of the swimming environment to produce a more productive use of time. The role of the coach was subsequently changed as less time was spent in directing and supervising behaviors.
Intensity control in swim training by means of the individual anaerobic threshold.
Skorski, Sabrina; Faude, Oliver; Urhausen, Axel; Kindermann, Wilfried; Meyer, Tim
2012-12-01
This study aimed at evaluating the homogeneity of physiological responses during swim training bouts with intensities prescribed by reference to the individual anaerobic threshold (IAT). Eighteen competitive front crawl swimmers (female 5, male 13, 10 long-distance, and 8 short-distance swimmers [LDSs, SDSs], age: 17 ± 1.7 years, training history: 7.0 ± 2.8 years, training volume per week: 35 ± 5.7 km) performed an incremental swimming test to determine the IAT. Within a maximum of 3 weeks, 4 training programs were conducted: 20 × 100-m low-intensity endurance training (EN(low), 97% IAT), 5 × 400-m high-intensity endurance training (EN(high), 101% IAT), 5 × 200 m (IT1, 105% IAT), and 10 × 100 m (IT2, 108% IAT) intensive interval training. Blood lactate concentrations (bLa) were determined during each training session. The results are given as median (25th and 75th percentiles). During EN(low) and EN(high), the mean bLas were 1.8 mmol·L(-1) (1.3/3.0 mmol·L(-1)) and 4.4 mmol·L(-1) (3.9/6.4 mmol·L(-1)). The bLas were higher during both IT programs: IT1, 6.3 mmol·L(-1) (5.6/7.2 mmol·L(-1)); IT2, 5.8 mmol·L(-1) (5.0/6.5 mmol·L(-1)). The bLas of most individuals were close to the median values (±2.4 mmol·L(-1)). However, in each of the training programs, some subjects showed bLa values that were clearly above (3-7 mmol·L(-1) higher). In particular, SDSs reached higher bLas at the same intensity compared with LDSs. It is concluded that intensity prescriptions by means of IAT seem to elicit an expected metabolic response in approximately 85% of swim training sessions. The observed average bLa is in the range of those recommended in the scientific literature.
Risk factors for shoulder pain and injury in swimmers: A critical systematic review.
Hill, Lee; Collins, Malcolm; Posthumus, Michael
2015-11-01
Swimming is one of the most popular recreational and competitive sporting activities. In the 2013/2014 swimming season, 9630 men and 12,333 women were registered with the National Collegiate Athletics Association in the USA. The repetitive nature of the swimming stroke and demanding training programs of its athletes raises a number of concerns regarding incidence and severity of injuries that a swimmer might experience during a competitive season. A number of risk factors have previously been identified but the level of evidence from individual studies, as well as the level of certainty that these factors predispose a swimmer to pain and injury, to our knowledge has yet to be critically evaluated in a systematic review. Therefore, the primary objective of this review is to conduct a systematic review to critically assess the published evidence for risk factors that may predispose a swimmer to shoulder pain and injury. Three electronic databases, ScienceDirect, PubMed and SpringerLink, were searched using keywords "(Injury OR pain) AND (Swim*)" and "(Shoulder) AND (Swim*)". Based on the inclusion and exclusion criteria, 2731 unique titles were identified and were analyzed to a final 29 articles. Only articles with a level of evidence of I, II and III were included according to robust study design and data analysis. The level of certainty for each risk factor was determined. No studies were determined to have a high level of certainty, clinical joint laxity and instability, internal/external rotation, previous history of pain and injury and competitive level were determined to have a moderate level of certainty. All other risk factors were evaluated as having a low level of certainty. Although several risk factors were identified from the reviewed studies, prospective cohort studies, larger sample sizes, consistent and robust measures of risk should be employed in future research.
Brackley, Victoria; Ball, Kevin; Tor, Elaine
2018-05-12
The effectiveness of the swimming turn is highly influential to overall performance in competitive swimming. The push-off or wall contact, within the turn phase, is directly involved in determining the speed the swimmer leaves the wall. Therefore, it is paramount to develop reliable methods to measure the wall-contact-time during the turn phase for training and research purposes. The aim of this study was to determine the concurrent validity and reliability of the Pool Pad App to measure wall-contact-time during the freestyle and backstroke tumble turn. The wall-contact-times of nine elite and sub-elite participants were recorded during their regular training sessions. Concurrent validity statistics included the standardised typical error estimate, linear analysis and effect sizes while the intraclass correlating coefficient (ICC) was used for the reliability statistics. The standardised typical error estimate resulted in a moderate Cohen's d effect size with an R 2 value of 0.80 and the ICC between the Pool Pad and 2D video footage was 0.89. Despite these measurement differences, the results from this concurrent validity and reliability analyses demonstrated that the Pool Pad is suitable for measuring wall-contact-time during the freestyle and backstroke tumble turn within a training environment.
Simulated front crawl swimming performance related to critical speed and critical power.
Toussaint, H M; Wakayoshi, K; Hollander, A P; Ogita, F
1998-01-01
Competitive pool swimming events range in distance from 50 to 1500 m. Given the difference in performance times (+/- 23-1000 s), the contribution of the aerobic and anaerobic energy systems changes considerably with race distance. In training practice the regression line between swimming distance and time (Distance = critical velocity x time + anaerobic swimming capacity) is used to determine the individual capacity of the aerobic and anaerobic metabolic pathways. Although there is confidence that critical velocity and anaerobic swimming capacity are fitness measures that separate aerobic and anaerobic components, a firm theoretical basis for the interpretation of these results does not exist. The purpose of this study was to evaluate the critical power concept and anaerobic swimming capacity as measures of the aerobic and anaerobic capacity using a modeling approach. A systems model was developed that relates the mechanics and energetics involved in front crawl swimming performance. From actual swimming flume measurements, the time dependent aerobic and anaerobic energy release was modeled. Data derived from the literature were used to relate the energy cost of front crawl swimming to swimming velocity. A balance should exist between the energy cost to swim a distance in a certain time and the concomitant aerobic and anaerobic energy release. The ensuing model was used to predict performance times over a range of distances (50-1500 m) and to calculate the regression line between swimming distance and time. Using a sensitivity analysis, it was demonstrated that the critical velocity is indicative for the capacity of the aerobic energy system. Estimates of the anaerobic swimming capacity, however, were influenced by variations in both anaerobic and aerobic energy release. Therefore, it was concluded that the anaerobic swimming capacity does not provide a reliable estimate of the anaerobic capacity.
Post-activation Potentiation in Propulsive Force after Specific Swimming Strength Training.
Barbosa, A C; Barroso, R; Andries, O
2016-04-01
We investigated whether a conditioning activity (8×12.5 m with 2.5 min-interval using both hand paddles and parachute) induced post-activation potentiation in swimming propulsive force and whether a swimmer's force level affected a post-activation potentiation response. 8 competitive swimmers (5 males and 3 females, age: 18.4±1.3 years; IPS=796±56) performed a 10 s maximum tethered swimming test 8 and 4 min before (the highest value was considered as PRE), and 2.5 and 6.5 min after (POST1 and POST2, respectively) the conditioning activity. Rate of force development was not affected, but peak force in POST1 (p=0.02) and impulse in both POST1 (p=0.007) and POST2 (p=0.004) were reduced. Possibly the conditioning activity induced greater fatigue than post-activation potentiation benefits. For instance, the number of repetitions might have been excessive, and rest intervals between the conditioning activity and POST1 and POST2 were possibly too short. There were positive correlations between PRE peak force and changes in peak force and rate of force development. Although conditioning activity was detrimental, positive correlations suggest that weaker swimmers experience a deterioration of performance more than the stronger ones. This conditioning activity is not recommended for swimmers with the current competitive level before a competitive event. © Georg Thieme Verlag KG Stuttgart · New York.
Predicting performance in competitive apnea diving, part II: dynamic apnoea.
Schagatay, Erika
2010-03-01
Part I of this series of articles identified the main physiological factors defining the limits of static apnea, while this paper reviews the factors involved when physical work is added in the dynamic distance disciplines, performed in shallow water in a swimming pool. Little scientific work has been done concerning the prerequisites and limitations of swimming with or without fins whilst breath holding to extreme limits. Apneic duration influences all competitive apnea disciplines, and can be prolonged by any means that increase gas storage or tolerance to asphyxia, or reduce metabolic rate, as reviewed in the first article. For horizontal underwater distance swimming, the main challenge is to restrict metabolism despite the work, and to direct blood flow only to areas where demand is greatest, to allow sustained function. Here, work economy, local tissue energy and oxygen stores and the anaerobic capacity of the muscles are key components. Improvements in swimming techniques and, especially in swimming with fins, equipment have already contributed to enhanced performance and may do so further. High lactate levels observed after competition swims suggest a high anaerobic component, and muscle hypoxia could ultimately limit muscle work and swimming distance. However, the frequency of syncope, especially in swimming without fins, suggests that cerebral oxygenation may often be compromised before this occurs. In these pool disciplines, safety is high and the dive can be interrupted by the competitor or safety diver within seconds. The safety routines in place during pool competitions are described.
Nutritional recommendations for synchronized swimming.
Robertson, Sherry; Benardot, Dan; Mountjoy, Margo
2014-08-01
The sport of synchronized swimming is unique, because it combines speed, power, and endurance with precise synchronized movements and high-risk acrobatic maneuvers. Athletes must train and compete while spending a great amount of time underwater, upside down, and without the luxury of easily available oxygen. This review assesses the scientific evidence with respect to the physiological demands, energy expenditure, and body composition in these athletes. The role of appropriate energy requirements and guidelines for carbohydrate, protein, fat, and micronutrients for elite synchronized swimmers are reviewed. Because of the aesthetic nature of the sport, which prioritizes leanness, the risks of energy and macronutrient deficiencies are of significant concern. Relative Energy Deficiency in Sport and disordered eating/eating disorders are also of concern for these female athletes. An approach to the healthy management of body composition in synchronized swimming is outlined. Synchronized swimmers should be encouraged to consume a well-balanced diet with sufficient energy to meet demands and to time the intake of carbohydrate, protein, and fat to optimize performance and body composition. Micronutrients of concern for this female athlete population include iron, calcium, and vitamin D. This article reviews the physiological demands of synchronized swimming and makes nutritional recommendations for recovery, training, and competition to help optimize athletic performance and to reduce risks for weight-related medical issues that are of particular concern for elite synchronized swimmers.
Pacing in Swimming: A Systematic Review.
McGibbon, Katie E; Pyne, D B; Shephard, M E; Thompson, K G
2018-03-20
Pacing strategy, or how energy is distributed during exercise, can substantially impact athletic performance and is considered crucial for optimal performance in many sports. This is particularly true in swimming given the highly resistive properties of water and low mechanical efficiency of the swimming action. The aim of this systematic review was to determine the pacing strategies utilised by competitive swimmers in competition and their reproducibility, and to examine the impact of different pacing strategies on kinematic, metabolic and performance variables. This will provide valuable and practical information to coaches and sports science practitioners. The databases Web of Science, Scopus, SPORTDiscus and PubMed were searched for published articles up to 1 August 2017. A total of 23 studies examining pool-based swimming competitions or experimental trials in English-language and peer-reviewed journals were included in this review. In short- and middle-distance swimming events maintenance of swimming velocity is critical, whereas in long-distance events a low lap-to-lap variability and the ability to produce an end spurt in the final lap(s) are key. The most effective strategy in the individual medley (IM) is to conserve energy during the butterfly leg to optimise performance in subsequent legs. The pacing profiles of senior swimmers remain relatively stable irrespective of opponents, competition stage or type, and performance time. Implementing event-specific pacing strategies should benefit the performance of competitive swimmers. Given differences between swimmers, there is a need for greater individualisation when considering pacing strategy selection across distances and strokes.
Mujika, I; Padilla, S; Pyne, D
2002-11-01
The purpose of this study was to determine the magnitude of the swimming performance change during the final 3 weeks of training (F3T) leading to the Sydney 2000 Olympic Games. Olympic swimmers who took part in the same event or events at the Telstra 2000 Grand Prix Series in Melbourne, Australia, (26 - 27 August 2000), and 21 - 28 d later at the Sydney 2000 Olympic Games (16 - 23 September 2000) were included in this analysis. A total of 99 performances (50 male, 49 female) were analysed. The overall performance improvement between pre- and post-F3T conditions for all swimmers was 2.18 +/- 1.50 % (p < 0.0001), (range - 1.14 % to 6.02 %). A total of 91 of the 99 analysed performances were faster after the F3T and only 8 were slower. The percentage improvement with F3T was significantly higher (P < 0.01) in males (2.57 +/- 1.45 %) than in females (1.78 +/- 1.45 %). In conclusion, the pre-Olympic F3T elicited a significant performance improvement of 2.57 % for male and 1.78 % for female swimmers at the Sydney 2000 Olympic Games. The magnitude was similar for all competition events, and was achieved by swimmers from different countries and performance levels. These data provide a quantitative framework for coaches and swimmers to set realistic performance goals based on individual performance levels before the final training phase leading to important competitions.
Airway dysfunction in elite swimmers: prevalence, impact, and challenges
Lomax, Mitch
2016-01-01
The prevalence of airway dysfunction in elite swimmers is among the highest in elite athletes. The traditional view that swimmers naturally gravitate toward swimming because of preexisting respiratory disorders has been challenged. There is now sufficient evidence that the higher prevalence of bronchial tone disorders in elite swimmers is not the result of a natural selection bias. Rather, the combined effects of repeated chlorine by-product exposure and chronic endurance training can lead to airway dysfunction and atopy. This review will detail the underpinning causes of airway dysfunction observed in elite swimmers. It will also show that airway dysfunction does not prevent success in elite level swimming. Neither does it inhibit lung growth and might be partially reversible when elite swimmers retire from competition. PMID:27274324
Tethered Swimming for the Evaluation and Prescription of Resistance Training in Young Swimmers.
Papoti, Marcelo; da Silva, Adelino S R; Kalva-Filho, Carlos Augusto; Araujo, Gustavo Gomes; Santiago, Vanessa; Martins, LuizEduardo Barreto; Cunha, Sérgio Augusto; Gobatto, Claudio Alexandre
2017-02-01
The aims of the present study were 1) to evaluate the effects of 11 weeks of a typical free-swimming training program on aerobic and stroke parameters determined in tethered swimming (Study 1; n=13) and 2) to investigate the responses of tethered swimming efforts, in addition to free-swimming sessions, through 7 weeks of training (Study 2; n=21). In both studies, subjects performed a graded exercise test in tethered swimming (GET) to determine anaerobic threshold (AnT), stroke rate at AnT (SR AnT ), peak force at GET (PF GET ) and peak blood lactate ([La-] GET ). Participants also swam 100-, 200- and 400-m lengths to evaluate performance. In Study 2, swimmers were divided into control (i. e., only free-swimming; GC [n=11]) and tethered swimming group (i. e., 50% of the main session; G TS [n=10]). The results of Study 1 demonstrate that AnT, PF GET , [La - ] GET and 200-m performance were improved with free-swimming training. The SR AnT decreased with training. In Study 2, free-swimming performance and most of the graded exercise test parameters were not altered in either group. However, [La-] GET improved only for G TS . These results demonstrate that aerobic parameters obtained in tethered swimming can be used to evaluate free-swimming training responses, and the addition of tethered efforts during training routine improves the lactate production capacity of swimmers. © Georg Thieme Verlag KG Stuttgart · New York.
Breaking the Myth That Relay Swimming Is Faster Than Individual Swimming.
Skorski, Sabrina; Etxebarria, Naroa; Thompson, Kevin G
2016-04-01
To investigate if swimming performance is better in a relay race than in the corresponding individual race. The authors analyzed 166 elite male swimmers from 15 nations in the same competition (downloaded from www.swimrankings.net). Of 778 observed races, 144 were Olympic Games performances (2000, 2004, 2012), with the remaining 634 performed in national or international competitions. The races were 100-m (n = 436) and 200-m (n = 342) freestyle events. Relay performance times for the 2nd-4th swimmers were adjusted (+ 0.73 s) to allow for the "flying start." Without any adjustment, mean individual relay performances were significantly faster for the first 50 m and overall time in the 100-m events. Furthermore, the first 100 m of the 200-m relay was significantly faster (P > .001). During relays, swimmers competing in 1st position did not show any difference compared with their corresponding individual performance (P > .16). However, swimmers competing in 2nd-4th relay-team positions demonstrated significantly faster times in the 100-m (P < .001) and first half of the 200-m relays than in their individual events (P < .001, ES: 0.28-1.77). However, when finishing times for 2nd-4th relay team positions were adjusted for the flying start no differences were detected between relay and individual race performance for any event or split time (P > .17). Highly trained swimmers do not swim (or turn) faster in relay events than in their individual races. Relay exchange times account for the difference observed in individual vs relay performance.
Swimming-induced pulmonary oedema an uncommon condition diagnosed with POCUS ultrasound.
Alonso, Joaquín Valle; Chowdhury, Motiur; Borakati, Raju; Gankande, Upali
2017-12-01
Swimming Induced Pulmonary Edema, or SIPE, is an emerging condition occurring in otherwise healthy individuals during surface swimming or diving that is characterized by cough, dyspnea, hemoptysis, and hypoxemia. It is typically found in those who spend time in cold water exercise with heavy swimming and surface swimming, such as civilian training for iron Man, triathalon, and military training. We report the case of a highly trained young female swimmer in excellent cardiopulmonary health, who developed acute alveolar pulmonary oedema in an open water swimming training diagnosed in the emergency department using POCUS ultrasound. Copyright © 2017 Elsevier Inc. All rights reserved.
Surveillance and Conformity in Competitive Youth Swimming
ERIC Educational Resources Information Center
Lang, Melanie
2010-01-01
Underpinned by a Foucauldian analysis of sporting practices, this paper identifies the disciplinary mechanism of surveillance at work in competitive youth swimming. It highlights the ways in which swimmers and their coaches are subject to and apply this mechanism to produce embodied conformity to normative behaviour and obedient, docile bodies.…
Rodríguez, F A
2000-06-01
This study compared the cardiorespiratory response of trained swimmers to 400-m unimpeded front crawl swimming (SW), treadmill running (TR) and ergometer cycling (EC) maximal exercise tests, and evaluated the validity and specificity of a method to measure maximal aerobic power in swimming. Two series of experiments were conducted. In series A (n=15), comparisons were made between VO2peak and other cardiorespiratory variables in three maximal tests: after 400-m SW, and during incremental TR and EC. In series B, VO2 peak and related variables were measured after SW and during EC (n=33). No significant differences were observed between VO2peak and VE in the three modes of exercise, although SW values tended to be higher. After SW, maximal ventilatory response was characterized by higher tidal volumes (VT) and lower respiratory rates (fR) as compared with TR and EC. The highest heart rate values (fH) were also observed in TR, followed by EC and SW. In series B, no significant differences were observed either in peak VO2 or VE, but fH was also lower in SW. A maximal 400-m unimpeded freestyle SW test yields essentially equal or nonsignificantly higher peak VO2 and VE values than during maximal TR or EC tests in trained swimmers. The specific maximal cardiorespiratory response to the SW test is characterized by higher VT, lower fR, and lower fH. Breath-by-breath measurements during the immediate recovery after a 400-m voluntary maximal swim is proposed as a valid and specific test for directly measuring maximal metabolic parameters and evaluating specific maximal aerobic power in swimming.
The prediction of swimming performance in competition from behavioral information.
Rushall, B S; Leet, D
1979-06-01
The swimming performances of the Canadian Team at the 1976 Olympic Games were categorized as being improved or worse than previous best times in the events contested. The two groups had been previously assessed on the Psychological Inventories for Competitive Swimmers. A stepwise multiple-discriminant analysis of the inventory responses revealed that 13 test questions produced a perfect discrimination of group membership. The resultant discriminant functions for predicting performance classification were applied to the test responses of 157 swimmers at the 1977 Canadian Winter National Swimming Championships. Using the same performance classification criteria the accuracy of prediction was not better than chance in three of four sex by performance classifications. This yielded a failure to locate a set of behavioral factors which determine swimming performance improvements in elite competitive circumstances. The possibility of sets of factors which do not discriminate between performances in similar environments or between similar groups of swimmers was raised.
Hydrodynamic profile of young swimmers: changes over a competitive season.
Barbosa, T M; Morais, J E; Marques, M C; Silva, A J; Marinho, D A; Kee, Y H
2015-04-01
The aim of this study was to analyze the changes in the hydrodynamic profile of young swimmers over a competitive season and to compare the variations according to a well-designed training periodization. Twenty-five swimmers (13 boys and 12 girls) were evaluated in (a) October (M1); (b) March (M2); and (c) June (M3). Inertial and anthropometrical measures included body mass, swimmer's added water mass, height, and trunk transverse surface area. Swimming efficiency was estimated by the speed fluctuation, stroke index, and approximate entropy. Active drag was estimated with the velocity perturbation method and the passive drag with the gliding decay method. Hydrodynamic dimensionless numbers (Froude and Reynolds numbers) and hull velocity (i.e., speed at Froude number = 0.42) were also calculated. No variable presented a significant gender effect. Anthropometrics and inertial parameters plus dimensionless numbers increased over time. Swimming efficiency improved between M1 and M3. There was a trend for both passive and active drag increase from M1 to M2, but being lower at M3 than at M1. Intra-individual changes between evaluation moments suggest high between- and within-subject variations. Therefore, hydrodynamic changes over a season occur in a non-linear fashion way, where the interplay between growth and training periodization explain the unique path flow selected by each young swimmer. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Nascimento, C C F; Padula, N; Milani, J G P O; Shimano, A C; Martinez, E Z; Mattiello-Sverzut, A C
2008-09-01
The objective of the present study was to determine to what extent, if any, swimming training applied before immobilization in a cast interferes with the rehabilitation process in rat muscles. Female Wistar rats, mean weight 260.52 +/- 16.26 g, were divided into 4 groups of 6 rats each: control, 6 weeks under baseline conditions; trained, swimming training for 6 weeks; trained-immobilized, swimming training for 6 weeks and then immobilized for 1 week; trained-immobilized-rehabilitated, swimming training for 6 weeks, immobilized for 1 week and then remobilized with swimming for 2 weeks. The animals were then sacrificed and the soleus and tibialis anterior muscles were dissected, frozen in liquid nitrogen and processed histochemically (H&E and mATPase). Data were analyzed statistically by the mixed effects linear model (P < 0.05). Cytoarchitectural changes such as degenerative characteristics in the immobilized group and regenerative characteristics such as centralized nucleus, fiber size variation and cell fragmentation in the groups submitted to swimming were more significant in the soleus muscle. The diameters of the lesser soleus type 1 and type 2A fibers were significantly reduced in the trained-immobilized group compared to the trained group (P < 0.001). In the tibialis anterior, there was an increase in the number of type 2B fibers and a reduction in type 2A fibers when trained-immobilized rats were compared to trained rats (P < 0.001). In trained-immobilized-rehabilitated rats, there was a reduction in type 2B fibers and an increase in type 2A fibers compared to trained-immobilized rats (P < 0.009). We concluded that swimming training did not minimize the deleterious effects of immobilization on the muscles studied and that remobilization did not favor tissue re-adaptation.
Isolated core training improves sprint performance in national-level junior swimmers.
Weston, Matthew; Hibbs, Angela E; Thompson, Kevin G; Spears, Iain R
2015-03-01
To quantify the effects of a 12-wk isolated core-training program on 50-m front-crawl swim time and measures of core musculature functionally relevant to swimming. Twenty national-level junior swimmers (10 male and 10 female, 16±1 y, 171±5 cm, 63±4 kg) participated in the study. Group allocation (intervention [n=10], control [n=10]) was based on 2 preexisting swim-training groups who were part of the same swimming club but trained in different groups. The intervention group completed the core training, incorporating exercises targeting the lumbopelvic complex and upper region extending to the scapula, 3 times/wk for 12 wk. While the training was performed in addition to the normal pool-based swimming program, the control group maintained their usual pool-based swimming program. The authors made probabilistic magnitude-based inferences about the effect of the core training on 50-m swim time and functionally relevant measures of core function. Compared with the control group, the core-training intervention group had a possibly large beneficial effect on 50-m swim time (-2.0%; 90% confidence interval -3.8 to -0.2%). Moreover, it showed small to moderate improvements on a timed prone-bridge test (9.0%; 2.1-16.4%) and asymmetric straight-arm pull-down test (23.1%; 13.7-33.4%), and there were moderate to large increases in peak EMG activity of core musculature during isolated tests of maximal voluntary contraction. This is the first study to demonstrate a clear beneficial effect of isolated core training on 50-m front-crawl swim performance.
Influence of Competitive-Anxiety on Heart Rate Variability in Swimmers
Fortes, Leonardo S.; da Costa, Bruna D. V.; Paes, Pedro P.; do Nascimento Júnior, José R.A.; Fiorese, Lenamar; Ferreira, Maria E.C.
2017-01-01
The aim of this study was to analyze the relationship between competitive anxiety and heart rate variability (HRV) in swimming athletes. A total of 66 volunteers (41 male and 27 female) who swam the 400-m freestyle in the Brazilian Swimming Championships participated. Thirty minutes before the 400-m freestyle event, the athletes answered the Competitive Anxiety Inventory (CSAI-2R) questionnaire, then underwent anthropometric (body weight, height, and skinfold thickness) and HRV measurements. Then, at a second meeting, held 3 h after the 400-m freestyle event, the athletes returned to the evaluation room for HRV measurement (Polar® RS800cx, Kempele, Finland). Multiple linear regression was used to evaluate the relationship between competitive anxiety and HRV. The multiple linear regression was performed in three blocks (block 1: cognitive anxiety, block 2: somatic anxiety, and block 3: self-confidence), adopting the forward model. The results indicated a significant association between cognitive anxiety (p = 0.001) and HRV. An increased magnitude of the association was observed when somatic anxiety was inserted in the model (p = 0.001). In contrast, self-confidence showed, which was inserted in block 3, no relationship with HRV (p = 0.27). It was concluded that cognitive and somatic anxieties were associated with the HRV of swimmers. Athletes with a high magnitude of cognitive and/or somatic anxiety demonstrated more significant autonomic nervous system disturbance. Practically, psychological interventions are needed to improve anxiety states that are specific to perform well, and to improve HRV. Key points The level of competitive-anxiety can predict HRV’s response after competition in young swimming athletes. Young swimming athletes who demonstrate higher competitive-anxiety, may present high autonomic nervous system disorder, which can be evaluated by HRV. Coaches are encouraged to periodically evaluate the competitive-anxiety of young swimming athletes. PMID:29238249
Water safety training as a potential means of reducing risk of young children's drowning.
Asher, K. N.; Rivara, F. P.; Felix, D.; Vance, L.; Dunne, R.
1995-01-01
OBJECTIVES: To determine the effects of training in swimming and water safety on young preschool-children's ability to recover safely from a simulated episode of falling into a swimming pool. DESIGN: Randomized trial of 12 or eight weeks' duration water safety and swimming lessons for children 24 to 42 months old. OUTCOME MEASURES: Swimming ability, deck behavior, water recovery, and swimming to side after jumping into pool were measured before, during, and after the training program. RESULTS: 109 children completed the study (61 in the 12 week group, 48 in the eight week group). The average age was 34.2 months, 54% were male. Swimming ability, deck behavior, water recovery, and jump and swim skills improved over baseline levels in both groups. By the end of training, the 12 week group improved more than the eight week group only in swimming ability. Improvements in water recovery and jump and swim skills were associated positively with changes in swimming ability. CONCLUSIONS: Swimming ability and safety skills of young preschool children can be improved through training. Such programs may offer some protection for children at risk of drowning and there was no indication that this program increased the risk of drowning. However, pool fencing, other barriers around water, and parental supervision still remain the most important prevention strategies to reduce drowning in young children. PMID:9346036
Lima, Frederico D.; Stamm, Daniel N.; Della-Pace, Iuri D.; Dobrachinski, Fernando; de Carvalho, Nélson R.; Royes, Luiz Fernando F.; Soares, Félix A.; Rocha, João B.; González-Gallego, Javier; Bresciani, Guilherme
2013-01-01
Background and Aims Although acute exhaustive exercise is known to increase liver reactive oxygen species (ROS) production and aerobic training has shown to improve the antioxidant status in the liver, little is known about mitochondria adaptations to aerobic training. The main objective of this study was to investigate the effects of the aerobic training on oxidative stress markers and antioxidant defense in liver mitochondria both after training and in response to three repeated exhaustive swimming bouts. Methods Wistar rats were divided into training (n = 14) and control (n = 14) groups. Training group performed a 6-week swimming training protocol. Subsets of training (n = 7) and control (n = 7) rats performed 3 repeated exhaustive swimming bouts with 72 h rest in between. Oxidative stress biomarkers, antioxidant activity, and mitochondria functionality were assessed. Results Trained group showed increased reduced glutathione (GSH) content and reduced/oxidized (GSH/GSSG) ratio, higher superoxide dismutase (MnSOD) activity, and decreased lipid peroxidation in liver mitochondria. Aerobic training protected against exhaustive swimming ROS production herein characterized by decreased oxidative stress markers, higher antioxidant defenses, and increases in methyl-tetrazolium reduction and membrane potential. Trained group also presented higher time to exhaustion compared to control group. Conclusions Swimming training induced positive adaptations in liver mitochondria of rats. Increased antioxidant defense after training coped well with exercise-produced ROS and liver mitochondria were less affected by exhaustive exercise. Therefore, liver mitochondria also adapt to exercise-induced ROS and may play an important role in exercise performance. PMID:23405192
Dalamitros, Athanasios A; Zafeiridis, Andreas S; Toubekis, Argyris G; Tsalis, George A; Pelarigo, Jailton G; Manou, Vasiliki; Kellis, Spiridon
2016-10-01
Dalamitros, AA, Zafeiridis, AS, Toubekis, AG, Tsalis, GA, Pelarigo, JG, Manou, V, and Kellis, S. Effects of short-interval and long-interval swimming protocols on performance, aerobic adaptations, and technical parameters: A training study. J Strength Cond Res 30(10): 2871-2879, 2016-This study compared 2-interval swimming training programs of different work interval durations, matched for total distance and exercise intensity, on swimming performance, aerobic adaptations, and technical parameters. Twenty-four former swimmers were equally divided to short-interval training group (INT50, 12-16 × 50 m with 15 seconds rest), long-interval training group (INT100, 6-8 × 100 m with 30 seconds rest), and a control group (CON). The 2 experimental groups followed the specified swimming training program for 8 weeks. Before and after training, swimming performance, technical parameters, and indices of aerobic adaptations were assessed. ΙΝΤ50 and ΙΝΤ100 improved swimming performance in 100 and 400-m tests and the maximal aerobic speed (p ≤ 0.05); the performance in the 50-m swim did not change. Posttraining V[Combining Dot Above]O2max values were higher compared with pretraining values in both training groups (p ≤ 0.05), whereas peak aerobic power output increased only in INT100 (p ≤ 0.05). The 1-minute heart rate and blood lactate recovery values decreased after training in both groups (p < 0.01). Stroke length increased in 100 and 400-m swimming tests after training in both groups (p ≤ 0.05); no changes were observed in stroke rate after training. Comparisons between groups on posttraining mean values, after adjusting for pretraining values, revealed no significant differences between ΙΝΤ50 and ΙΝΤ100 for all variables; however, all measures were improved vs. the respective values in the CON (p < 0.001-0.05). In conclusion, when matched for distance and exercise intensity, the short-interval (50 m) and long-interval (100 m) protocols confer analogous improvements in swimming performance, in stroke cycle parameters, and in indices of aerobic adaptations after 8 weeks of training.
The physiology and biomechanics of competitive swimming.
Troup, J P
1999-04-01
Fast swimming, either in the pool, in open water swimming, or in water polo and synchronized swimming, requires maximizing the efficiencies with which the human body can move through a liquid medium. A multitude of factors can affect the ability to swim fast as well as the final outcome. Physiology and biomechanics are the present tools used by sports scientists to determine which factors are important to fast swimming and, subsequently, to determine how the swimmer may maximize these factors to improve performance.
Liposek, Silvester; Zenic, Natasa; Saavedra, Jose M; Sekulic, Damir; Rodek, Jelena; Marinsek, Miha; Sajber, Dorica
2018-01-01
Although coaching is considered an important determinant of athletes’ potential doping behavior (PDB), there is an evident lack of studies that have examined coaching-strategy-and-training-methodology (CS&TM) in relation to PDB. This study was aimed to identify the specific associations that may exist between CS&TM -factors and other factors, and PDB in high-level swimming. The sample comprised 94 swimmers (35 females; 19.7 ± 2.3 years of age) and consisted of swimmers older than 18 years who participated in the 2017 National Championship. Variables were collected by previously validated questionnaires, with the addition of questions where athletes were asked about CS&TM to which they had been exposed. Multinomial logistic regression was applied for the criterion PDB (Negative PDB – Neutral PDB – Positive PDB). The higher risk for positive-PDB was found in males (OR: 6.58; 95%CI: 1.01-9.12); therefore, all regressions were adjusted for gender. Those swimmers who achieved better competitive result were less prone to neutral-PDB (0.41; 0.17-0.98). The positive-PDB was evidenced in those swimmers who perceived that their training was monotonous and lacked diversity (1.82; 1.41-5.11), and who were involved in training which was mostly oriented toward volume (1.76; 1.11-7.12). The lower likelihood of positive-PDB is found in those who replied that technique is practiced frequently (0.12; 0.01-0.81), those who replied that coach regularly provided the attention to explain the training aims (0.21; 0.04-0.81), and that coach frequently reviewed and discussed the quality of execution of specific tasks (0.41; 0.02-0.81). The findings on the relationships between the studied variables and PDB should be incorporated into targeted anti-doping efforts in swimming. Further studies examining sport-specific variables of CS&TM in younger swimmers and other sports are warranted. Key points The opinions about doping presence in swimming were not associated with athletes’ doping susceptibility, but a higher doping tendency is found in male swimmers Swimmers were generally more susceptible to doping if they perceived that their training lacked work on improvement and mastering of the swimming technique Those swimmers who are more prone to doping frequently stated that their coach did not provide the necessary attention to explain the training aims, and did not sufficiently review and discuss the quality of the athlete’s execution of specific tasks Results highlight importance of coaching strategy and training methodology as possible covariates of doping susceptibility in sports. PMID:29535581
Poiss, Candice C; Sullivan, Patricia A; Paup, Donald C; Westerman, Beverly J
2004-02-01
The purpose of this study was to examine differences in perception of the importance of weight training as a part of general and sport-specific training for selected collegiate men and women student-athletes. Subjects included 139 men and 165 women varsity National Collegiate Athletic Association Division III student-athletes who participated in the following sports: baseball, basketball, field hockey, football, lacrosse, soccer, softball, swimming, tennis, track & field, or volleyball. Men student-athletes were significantly more likely to consider weight training essential to their general and sport-specific training than women student-athletes, as measured by the Training Information Survey. Additionally, men student-athletes were found to be significantly more competitive and win-oriented than women student-athletes (p < 0.001) as measured by the Sport Orientation Questionnaire, which is consistent with previous research. Results also showed that only highly goal-oriented student-athletes perceived weight training as: (a) important to both men and women and (b) having both feminine and masculine traits. It was concluded that significant gender differences exist in the perceived importance of weight training and that the constructs of competitiveness, win and goal orientation, may influence a student-athlete's perception of the importance of weight training. Coaches of both men and women student-athletes must teach that weight training is important for female and male student-athletes.
Ghiasi, Rafigheh; Ghadiri Soufi, Farhad; Somi, Mohammad Hossein; Mohaddes, Gisou; Mirzaie Bavil, Fariba; Naderi, Roya; Alipour, Mohammad Reza
2015-09-01
Insulin resistance plays a key role in the onset and development of type 2 diabetes mellitus (T2DM) and its complications. In this study, we evaluated the effect of swim training on insulin resistance in diabetic rats. Forty male Wistar rats were randomly divided into four groups (n=10): sedentary control (Con), sedentary diabetic (Dia), swim trained control (Exe) and swim trained diabetic (Dia+Exe) rats. Diabetes was induced by high fat diet (HFD) and a low dose of streptozotocin (35 mg/kg, i.p). In trained groups, one week after the induction of diabetes, animals were subjected to swimming (60 min/5 days a week) for 10 weeks. At the end of training, fasting blood sugar (FBS), oral glucose tolerance test (OGTT), fasting/basal insulin, glycosylated hemoglobin (HbA1c) levels, insulin resistance index, homeostasis model assessment method (HOMA-IR), triglycerides (TG,) total cholesterol (TCh), and high density lipoprotein (HDL) levels in blood were measured. Swimming significantly improved OGTT (P<0.01) and HOMA-IR (P<0.01). Swim training also significantly decreased FBS (p<0.01), fasting/basal insulin (P<0.01), HbA1C (p<0.01), TG (P<0.05), and TCh (P<0.05) levels. It also significantly increased HDL (p<0.05) level. Our findings indicate that swim training improved glycemic control and insulin sensitivity in type 2 diabetes caused by high fat diet in male rats.
The Fluid Dynamics of Competitive Swimming
NASA Astrophysics Data System (ADS)
Wei, Timothy; Mark, Russell; Hutchison, Sean
2014-01-01
Nowhere in sport is performance so dependent on the interaction of the athlete with the surrounding medium than in competitive swimming. As a result, understanding (at least implicitly) and controlling (explicitly) the fluid dynamics of swimming are essential to earning a spot on the medal stand. This is an extremely complex, highly multidisciplinary problem with a broad spectrum of research approaches. This review attempts to provide a historical framework for the fluid dynamics-related aspects of human swimming research, principally conducted roughly over the past five decades, with an emphasis on the past 25 years. The literature is organized below to show a continuous integration of computational and experimental technologies into the sport. Illustrations from the authors' collaborations over a 10-year period, coupling the knowledge and experience of an elite-level coach, a lead biomechanician at USA Swimming, and an experimental fluid dynamicist, are intended to bring relevance and immediacy to the review.
The impact of triathlon training and racing on athletes' general health.
Vleck, Veronica; Millet, Gregoire P; Alves, Francisco Bessone
2014-12-01
Although the sport of triathlon provides an opportunity to research the effect of multi-disciplinary exercise on health across the lifespan, much remains to be done. The literature has failed to consistently or adequately report subject age group, sex, ability level, and/or event-distance specialization. The demands of training and racing are relatively unquantified. Multiple definitions and reporting methods for injury and illness have been implemented. In general, risk factors for maladaptation have not been well-described. The data thus far collected indicate that the sport of triathlon is relatively safe for the well-prepared, well-supplied athlete. Most injuries 'causing cessation or reduction of training or seeking of medical aid' are not serious. However, as the extent to which they recur may be high and is undocumented, injury outcome is unclear. The sudden death rate for competition is 1.5 (0.9-2.5) [mostly swim-related] occurrences for every 100,000 participations. The sudden death rate is unknown for training, although stroke risk may be increased, in the long-term, in genetically susceptible athletes. During heavy training and up to 5 days post-competition, host protection against pathogens may also be compromised. The incidence of illness seems low, but its outcome is unclear. More prospective investigation of the immunological, oxidative stress-related and cardiovascular effects of triathlon training and competition is warranted. Training diaries may prove to be a promising method of monitoring negative adaptation and its potential risk factors. More longitudinal, medical-tent-based studies of the aetiology and treatment demands of race-related injury and illness are needed.
Bentley, David J; Cox, Gregory R; Green, Daniel; Laursen, Paul B
2008-07-01
Triathlon is a sport consisting of sequential swimming, cycling and running. The main diversity within the sport of triathlon resides in the varying event distances, which creates specific technical, physiological and nutritional considerations for athlete and practitioner alike. The purpose of this article is to review physiological as well as nutritional aspects of triathlon and to make recommendations on ways to enhance performance. Aside from progressive conditioning and training, areas that have shown potential to improve triathlon performance include drafting when possible during both the swim and cycle phase, wearing a wetsuit, and selecting a lower cadence (60-80 rpm) in the final stages of the cycle phase. Adoption of a more even racing pace during cycling may optimise cycling performance and induce a "metabolic reserve" necessary for elevated running performance in longer distance triathlon events. In contrast, drafting in swimming and cycling may result a better tactical approach to increase overall performance in elite Olympic distance triathlons. Daily energy intake should be modified to reflect daily training demands to assist triathletes in achieving body weight and body composition targets. Carbohydrate loading strategies and within exercise carbohydrate intake should reflect the specific requirements of the triathlon event contested. Development of an individualised fluid plan based on previous fluid balance observations may assist to avoid both dehydration and hyponatremia during prolonged triathlon racing.
How animals drink and swim in fluids
NASA Astrophysics Data System (ADS)
Jung, Sunghwan
2011-10-01
Fluids are essential for most living organisms to maintain a healthy body and also serve as a medium in which they locomote. The fluid bulk or interfaces actively interact with biological structures, which produces highly nonlinear, interesting, and complicated dynamical problems. We studied the lapping of cats and the swimming of Paramecia in various fluidic environments. The problem of the cat drinking can be simplified as the competition between inertia and gravity whereas the problem of Paramecium swimming in viscous fluids results from the competition between viscous drag and thrust. The underlying mechanisms are discussed and understood through laboratory experiments utilizing high-speed photography.
Characteristics of elite open-water swimmers.
VanHeest, Jaci L; Mahoney, Carrie E; Herr, Larry
2004-05-01
Open-water swimming (5, 10, and 25 km) has many unique challenges that separate it from other endurance sports, like marathon running and cycling. The characteristics of a successful open-water swimmer are unclear. The purpose of this study was to determine the physical and metabolic characteristics of a group of elite-level open-water swimmers. The open-water swimmers were participating in a 1-week training camp. Anthropometric, metabolic, and blood chemistry assessments were performed on the athletes. The swimmers had a VO(2)peak of 5.51 +/- 0.96 and 5.06 +/- 0.57 ml.kg(-1).min(-1) for males and females, respectively. Their lactate threshold (LT) occurred at a pace equal to 88.75% of peak pace for males and 93.75% for females. These elite open-water swimmers were smaller and lighter than competitive pool swimmers. They possess aerobic metabolic alterations that resulted in enhanced performance in distance swimming. Trainers and coaches should develop dry-land programs that will improve the athlete's muscular endurance. Furthermore, programs should be designed to increase the LT velocity as a percentage of peak swimming velocity.
Strength Training and Detraining in Different Populations: Case Studies
Marques, Mário C.; Zajac, Adam; Pereira, Ana; Costa, Aldo M.
2011-01-01
Many researchers have demonstrated that a specific strength training program can improve maximal strength and, the rate of force production, reduce the incidence of muscle-skeletal injury, and contribute to faster injury recovery times, thereby minimizing the number of missed practice sessions or competitions. Yet, to our best knowledge, there is no apparent consensus on the appropriate method of muscle strength and power training to enhance performance in distinct populations groups. Interruptions in training process because of illness, injury, holidays, post-season break or other factors are normal situations in any kind of sport. However, the detraining period and its consequences are not well reported in sports literature, and namely during puberty. Therefore, the aim of this paper was to discuss several case studies concerning different populations such us physical students, age-swimming competitors and elite power athletes. PMID:23487418
Morning Exercise: Enhancement of Afternoon Sprint-Swimming Performance.
McGowan, Courtney J; Pyne, David B; Thompson, Kevin G; Raglin, John S; Rattray, Ben
2017-05-01
An exercise bout completed several hours prior to an event may improve competitive performance later that same day. To examine the influence of morning exercise on afternoon sprint-swimming performance. Thirteen competitive swimmers (7 male, mean age 19 ± 3 y; 6 female, mean age 17 ± 3 y) completed a morning session of 1200 m of variedintensity swimming (SwimOnly), a combination of varied-intensity swimming and a resistance-exercise routine (SwimDry), or no morning exercise (NoEx). After a 6-h break, swimmers completed a 100-m time trial. Time-trial performance was faster in SwimOnly (1.6% ± 0.6, mean ± 90% confidence limit, P < .01) and SwimDry (1.7% ± 0.7%, P < .01) than in NoEx. Split times for the 25- to 50-m distance were faster in both SwimOnly (1.7% ± 1.2%, P = .02) and SwimDry (1.5% ± 0.8%, P = .01) than in NoEx. The first 50-m stroke rate was higher in SwimOnly (0.70 ± 0.21 Hz, mean ± SD, P = .03) and SwimDry (0.69 ± 0.18 Hz, P = .05) than in NoEx (0.64 ± 0.16 Hz). Before the afternoon session, core (0.2°C ± 0.1°C [mean ± 90% confidence limit], P = .04), body (0.2°C ± 0.1°C, P = .02), and skin temperatures (0.3°C ± 0.3°C, P = .02) were higher in SwimDry than in NoEx. Completion of a morning swimming session alone or together with resistance exercise can substantially enhance sprint-swimming performance completed later the same day.
Multi-age-grouping paradigm for young swimmers.
Kojima, Kosuke; Jamison, Paul L; Stager, Joel M
2012-01-01
The purpose of this study was to examine the adequacy of "multi-age" classification systems in youth sports with a specific focus on the unisex multi-age-groupings used by USA Swimming. In addition, we offer an analytical rationale for the multi-age-groupings and potential alternatives. We examined the top 100 US swim performances for three years (2005, 2006, and 2007) for girls and boys in 15 age-groups (7 to 20 years and a singular group of 21 years and older). Data for each age and sex were pooled over the three years and means were calculated for each of seven competitive swim events. Swim times differed among each age up to the 14-year age-group in girls (F (14,30885) = 183.9, P < 0.01, Cohen's d = 1.19-3.72, large effect) and 16-year age-group in boys (F (14,30885) = 308.7, P < 0.01, Cohen's d = 0.81-3.64, large effect) for all events. Age-related differences in swim times continued later in boys than girls likely due to differences between the sexes in timing of growth and maturation. Because of the differences in swim performance in contemporary multi-age-groups, stratifying swimmers by a single age is the best means to ensure competitive fairness and equality, although there is no rationale for swimmers under the age of 8 years to compete in separate unisex competitive groups.
Heart-Rate Recovery After Warm-up in Swimming: A Useful Predictor of Training Heart-Rate Response?
Ganzevles, Sander P M; de Haan, Arnold; Beek, Peter J; Daanen, Hein A M; Truijens, Martin J
2017-07-01
For training to be optimal, daily training load has to be adapted to the momentary status of the individual athlete, which is often difficult to establish. Therefore, the current study investigated the predictive value of heart-rate recovery (HRR) during a standardized warm-up for training load. Training load was quantified by the variation in heart rate during standardized training in competitive swimmers. Eight female and 5 male Dutch national-level swimmers participated in the study. They all performed 3 sessions consisting of a 300-m warm-up test and a 10 × 100-m training protocol. Both protocols were swum in front crawl at individually standardized velocities derived from an incremental step test. Velocity was related to 75% and 85% heart-rate reserve (% HR res ) for the warm-up and training, respectively. Relative HRR during the first 60 s after the warm-up (HR Rw-up ) and differences between the actual and intended heart rate for the warm-up and the training (ΔHR w-up and ΔHR tr ) were determined. No significant relationship between HRR w-up and ΔHR tr was found (F 1,37 = 2.96, P = .09, R 2 = .07, SEE = 4.65). There was considerable daily variation in ΔHR tr at a given swimming velocity (73-93% HR res ). ΔHR w-up and ΔHR tr were clearly related (F 1,37 = 74.31, P < .001, R 2 = .67, SEE = 2.78). HRR after a standardized warm-up does not predict heart rate during a directly subsequent and standardized training session. Instead, heart rate during the warm-up protocol seems a promising alternative for coaches to make daily individual-specific adjustments to training programs.
Air quality and exercise-induced bronchoconstriction in elite athletes.
Rundell, Kenneth W; Sue-Chu, Malcolm
2013-08-01
A higher prevalence of airway hyperresponsiveness, airway remodeling, and asthma has been identified among athletes who compete and train in environmental conditions of cold dry air and/or high air pollution. Repeated long-duration exposure to cold/dry air at high minute ventilation rates can cause airway damage. Competition or training at venues close to busy roadways, or in indoor ice arenas or chlorinated swimming pools, harbors a risk for acute and chronic airway disorders from high pollutant exposure. This article discusses the effects of these harsh environments on the airways, and summarizes potential mechanisms and prevalence of airway disorders in elite athletes. Copyright © 2013 Elsevier Inc. All rights reserved.
Alkatan, Mohammed; Machin, Daniel R; Baker, Jeffrey R; Akkari, Amanda S; Park, Wonil; Tanaka, Hirofumi
2016-01-01
Swimming exercise is an ideal and excellent form of exercise for patients with osteoarthritis (OA). However, there is no scientific evidence that regular swimming reduces vascular dysfunction and inflammation and elicits similar benefits compared with land-based exercises such as cycling in terms of reducing vascular dysfunction and inflammation in patients with OA. Forty-eight middle-aged and older patients with OA were randomly assigned to swimming or cycling training groups. Cycling training was included as a non-weight-bearing land-based comparison group. After 12 weeks of supervised exercise training, central arterial stiffness, as determined by carotid-femoral pulse wave velocity, and carotid artery stiffness, through simultaneous ultrasound and applanation tonometry, decreased significantly after both swimming and cycling training. Vascular endothelial function, as determined by brachial flow-mediated dilation, increased significantly after swimming but not after cycling training. Both swimming and cycling interventions reduced interleukin-6 levels, whereas no changes were observed in other inflammatory markers. In conclusion, these results indicate that regular swimming exercise can exert similar or even superior effects on vascular function and inflammatory markers compared with land-based cycling exercise in patients with OA who often has an increased risk of developing cardiovascular disease. Copyright © 2016 Elsevier Inc. All rights reserved.
Casuso, Rafael A; Aragón-Vela, Jerónimo; López-Contreras, Gracia; Gomes, Silvana N; Casals, Cristina; Barranco-Ruiz, Yaira; Mercadé, Jordi J; Huertas, Jesus R
2017-03-01
Casuso, Rafael A., Jerónimo Aragón-Vela, Gracia López-Contreras, Silvana N. Gomes, Cristina Casals, Yaira Barranco-Ruiz, Jordi J. Mercadé, and Jesus R. Huertas. Does swimming at a moderate altitude favor a lower oxidative stress in an intensity-dependent manner? Role of nonenzymatic antioxidants. High-Alt Med Biol. 18:46-55, 2017.-we aimed to describe oxidative damage and enzymatic and nonenzymatic antioxidant responses to swimming at different intensities in hypoxia. We recruited 12 highly experienced swimmers who have been involved in competitive swimming for at least 9 years. They performed a total of six swimming sessions carried out at low (LOW), moderate (MOD), or high (HIGH) intensity at low altitude (630 m) and at 2320 m above sea level. Blood samples were collected before the session (Pre), after the cool down (Post), and after 15 minutes of recovery (Rec). Blood lactate (BL) and heart rate were recorded throughout the main part of the session. Average velocities did not change between hypoxia and normoxia. We found a higher BL in response to MOD intensity in hypoxia. Plasmatic hydroperoxide level decreased at all intensities when swimming in hypoxia. This effect coincided with a lower glutation peroxidase activity and a marked mobilization of the circulating levels of α-tocopherol and coenzyme Q10 in an intensity-dependent manner. Our results suggest that, regardless of the intensity, no oxidative damage is found in response to hypoxic swimming in well-trained swimmers. Indeed, swimmers show a highly efficient antioxidant system by stimulating the mobilization of nonenzymatic antioxidants.
Nonato, L F; Rocha-Vieira, E; Tossige-Gomes, R; Soares, A A; Soares, B A; Freitas, D A; Oliveira, M X; Mendonça, V A; Lacerda, A C; Massensini, A R; Leite, H R
2016-09-29
Although it is well known that physical training ameliorates brain oxidative function after injuries by enhancing the levels of neurotrophic factors and oxidative status, there is little evidence addressing the influence of exercise training itself on brain oxidative damage and data is conflicting. This study investigated the effect of well-established swimming training protocol on lipid peroxidation and components of antioxidant system in the rat brain. Male Wistar rats were randomized into trained (5 days/week, 8 weeks, 30 min; n=8) and non-trained (n=7) groups. Forty-eight hours after the last session of exercise, animals were euthanized and the brain was collected for oxidative stress analysis. Swimming training decreased thiobarbituric acid reactive substances (TBARS) levels (P<0.05) and increased the activity of the antioxidant enzyme superoxide dismutase (SOD) (P<0.05) with no effect on brain non-enzymatic total antioxidant capacity, estimated by FRAP (ferric-reducing antioxidant power) assay (P>0.05). Moreover, the swimming training promoted metabolic adaptations, such as increased maximal workload capacity (P<0.05) and maintenance of body weight. In this context, the reduced TBARS content and increased SOD antioxidant activity induced by 8 weeks of swimming training are key factors in promoting brain resistance. In conclusion, swimming training attenuated oxidative damage and increased enzymatic antioxidant but not non-enzymatic status in the rat brain.
Lima-Borges, Dayanne S; Martinez, Paula F; Vanderlei, Luiz Carlos M; Barbosa, Fernando S S; Oliveira-Junior, Silvio A
2018-03-28
Young athletes' participation in competitive sports is becoming increasingly common, and this increased involvement raises concerns about the occurrence of overtraining and sports injuries. Since these issues are poorly understood, this study analyzed heart rate variability, stress/recovery relationship, and sports injury incidence during a training macrocycle of young sprint and endurance swimmers. Thirty teenage swimmers (aged 12 to 17 years) were divided into two groups as follows: Sprint (n = 17) and Endurance (n = 13). Subjects were evaluated over 20 weeks, based on the following three schedules: general, specific, and competitive. In addition to heart rate variability and sports injury incidence, the Recovery-Stress-Questionnaire of Athletes was used to analyse stress/recovery states in athletes. All procedures were developed at the initial moment and at the end of each periodization step. The Sprint group presented a reduced standard deviation of normal-normal beats (73.0 ± 6.6 vs. 54.1 ± 3.5 ms; p < 0.05) and root mean square of the successive differences (55.3 ± 6.2 vs. 42.0 ± 3.7 ms; p < 0.01) from the period of general preparation until the time of competition. Recovery-stress monitoring was affected only by the swimming training periodization (p < 0.05). During the general period, differences between recovery and stress scales were correlated directly with the root mean square of the successive differences (r = 0.576; p = 0.001), the standard deviation of instantaneous variability beat-to-beat (r = 0.521; p = 0.003) and the triangular index (r = 0.476; p = 0.008). Differences between general recovery and stress scales were inversely correlated with geometric indexes after the specific training period. Moreover, the Sprint group showed a higher incidence of sports injury than the Endurance group (0.0214 ± 0.0068 vs. 0.0136 ± 0.0050 cases/1000 hours). Sprint training was associated with progressive activation of the sympathetic nervous system as well as a higher incidence of sports injury in comparison to endurance swimming during a training macrocycle.
Underwater near-infrared spectroscopy can measure training adaptations in adolescent swimmers
Parry, Dave; Cooper, Chris E.
2018-01-01
The development of an underwater near-infrared spectroscopy (uNIRS) device has enabled previously unattainable measurements of peripheral muscle hemodynamics and oxygenation to be taken within the natural aquatic environment. The purposes of this study were (i) to trial the use of uNIRS, in a real world training study, and (ii) to monitor the effects of a swim training program upon muscle oxygenation status in short distance swimming. A total of 14 junior club level swimmers completed a repeated swim sprint test before and after an eight week endurance training program. A waterproof, portable Near-Infrared Spectroscopy device was attached to the vastus lateralis. uNIRS successfully measured changes in muscle oxygenation and blood volume in all individuals; rapid sub-second time resolution of the device was able to demonstrate muscle oxygenation changes during the characteristic swim movements. Post training heart rate recovery and swim performance time were significantly improved. uNIRS data also showed significant changes. A larger rise in deoxyhemoglobin during individual sprints suggested training induced an increase in muscle oxygen extraction; a faster recovery time for muscle oxygenation suggested positive training induced changes and significant changes in muscle blood flow also occur. As a strong correlation was seen between an increased reoxygenation rate and an improved swim performance time, these findings support the use of uNIRS as a new performance analysis tool in swimming. PMID:29692951
Underwater near-infrared spectroscopy can measure training adaptations in adolescent swimmers.
Jones, Ben; Parry, Dave; Cooper, Chris E
2018-01-01
The development of an underwater near-infrared spectroscopy (uNIRS) device has enabled previously unattainable measurements of peripheral muscle hemodynamics and oxygenation to be taken within the natural aquatic environment. The purposes of this study were (i) to trial the use of uNIRS, in a real world training study, and (ii) to monitor the effects of a swim training program upon muscle oxygenation status in short distance swimming. A total of 14 junior club level swimmers completed a repeated swim sprint test before and after an eight week endurance training program. A waterproof, portable Near-Infrared Spectroscopy device was attached to the vastus lateralis . uNIRS successfully measured changes in muscle oxygenation and blood volume in all individuals; rapid sub-second time resolution of the device was able to demonstrate muscle oxygenation changes during the characteristic swim movements. Post training heart rate recovery and swim performance time were significantly improved. uNIRS data also showed significant changes. A larger rise in deoxyhemoglobin during individual sprints suggested training induced an increase in muscle oxygen extraction; a faster recovery time for muscle oxygenation suggested positive training induced changes and significant changes in muscle blood flow also occur. As a strong correlation was seen between an increased reoxygenation rate and an improved swim performance time, these findings support the use of uNIRS as a new performance analysis tool in swimming.
Effects of 8-Week Training on Aerobic Capacity and Swimming Performance of Boys Aged 12 Years
ERIC Educational Resources Information Center
Zarzeczny, Ryszard; Kuberski, Mariusz; Deska, Agnieszka; Zarzeczna, Dorota; Rydz, Katarzyna; Lewandowska, Anna; Balchanowski, Tomasz; Bosiacki, Janusz
2011-01-01
Study aim: To assess the effects of 8-week endurance training in swimming on work capacity of boys aged 12 years. Material and methods: The following groups of schoolboys aged 12 years were studied: untrained control (UC; n = 14) and those training swimming for two years. The latter ones were subjected to 8-week training in classical style (CS; n…
Liposek, Silvester; Zenic, Natasa; Saavedra, Jose M; Sekulic, Damir; Rodek, Jelena; Marinsek, Miha; Sajber, Dorica
2018-03-01
Although coaching is considered an important determinant of athletes' potential doping behavior (PDB), there is an evident lack of studies that have examined coaching-strategy-and-training-methodology (CS&TM) in relation to PDB. This study was aimed to identify the specific associations that may exist between CS&TM -factors and other factors, and PDB in high-level swimming. The sample comprised 94 swimmers (35 females; 19.7 ± 2.3 years of age) and consisted of swimmers older than 18 years who participated in the 2017 National Championship. Variables were collected by previously validated questionnaires, with the addition of questions where athletes were asked about CS&TM to which they had been exposed. Multinomial logistic regression was applied for the criterion PDB (Negative PDB - Neutral PDB - Positive PDB). The higher risk for positive-PDB was found in males (OR: 6.58; 95%CI: 1.01-9.12); therefore, all regressions were adjusted for gender. Those swimmers who achieved better competitive result were less prone to neutral-PDB (0.41; 0.17-0.98). The positive-PDB was evidenced in those swimmers who perceived that their training was monotonous and lacked diversity (1.82; 1.41-5.11), and who were involved in training which was mostly oriented toward volume (1.76; 1.11-7.12). The lower likelihood of positive-PDB is found in those who replied that technique is practiced frequently (0.12; 0.01-0.81), those who replied that coach regularly provided the attention to explain the training aims (0.21; 0.04-0.81), and that coach frequently reviewed and discussed the quality of execution of specific tasks (0.41; 0.02-0.81). The findings on the relationships between the studied variables and PDB should be incorporated into targeted anti-doping efforts in swimming. Further studies examining sport-specific variables of CS&TM in younger swimmers and other sports are warranted.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-04-05
... recurring marine event that conducts swimming competitions. Special local regulations are necessary to... include sailing regattas, power boat races, swim races and holiday parades. For a description of the... Columbia Aquatics Club sponsors the ``Maryland Swim for Life'', on the waters of the Chester River near...
Guignard, Brice; Rouard, Annie; Chollet, Didier; Hart, John; Davids, Keith; Seifert, Ludovic
2017-08-01
Displacement in competitive swimming is highly dependent on fluid characteristics, since athletes use these properties to propel themselves. It is essential for sport scientists and practitioners to clearly identify the interactions that emerge between each individual swimmer and properties of an aquatic environment. Traditionally, the two protagonists in these interactions have been studied separately. Determining the impact of each swimmer's movements on fluid flow, and vice versa, is a major challenge. Classic biomechanical research approaches have focused on swimmers' actions, decomposing stroke characteristics for analysis, without exploring perturbations to fluid flows. Conversely, fluid mechanics research has sought to record fluid behaviours, isolated from the constraints of competitive swimming environments (e.g. analyses in two-dimensions, fluid flows passively studied on mannequins or robot effectors). With improvements in technology, however, recent investigations have focused on the emergent circular couplings between swimmers' movements and fluid dynamics. Here, we provide insights into concepts and tools that can explain these on-going dynamic interactions in competitive swimming within the theoretical framework of ecological dynamics.
Anttila, K; Jokikokko, E; Erkinaro, J; Järvilehto, M; Mänttäri, S
2011-02-01
The relative amount of muscle contraction regulating dihydropyridine and ryanodine receptors in the swimming muscles of trained reared Atlantic salmon Salmo salar smolts was compared with those of untrained and wild smolts. After an optimized 2 week training period, i.e. swimming with a velocity of 1·5 body lengths per second for 6 h per day, the level of both receptors was significantly higher in the muscles of trained S. salar than in the untrained ones before they were released into the natural environment. This difference persisted after downstream migration in the river. The highest level of receptors was observed in wild S. salar. Swimming performance was also higher in trained fish compared to untrained ones. Furthermore, swimming performance was positively associated with the level of receptors in both red and white muscle types. Downstream migration after release into the wild was significantly slower in trained smolts than in untrained fish. This indicates that trained smolts were most probably swimming harder against the current in the river than untrained smolts. The possible advantages for a slower migration in the river are discussed. This study shows that the prerequisites for effective contraction of the swimming muscles are better met in trained S. salar compared to untrained fish, and the muscles of trained smolts more closely resemble those of wild smolts. The results also imply that the capacity of untrained, reared smolts to swim against the current is not equal to that of their trained or wild counterparts which affects the downstream migration pattern of S. salar smolts. © 2011 The Authors. Journal of Fish Biology © 2011 The Fisheries Society of the British Isles.
Current Warm-Up Practices and Contemporary Issues Faced by Elite Swimming Coaches.
McGowan, Courtney J; Pyne, David B; Raglin, John S; Thompson, Kevin G; Rattray, Ben
2016-12-01
McGowan, CJ, Pyne, DB, Raglin, JS, Thompson, KG, and Rattray, B. Current warm-up practices and contemporary issues faced by elite swimming coaches. J Strength Cond Res 30(12): 3471-3480, 2016-A better understanding of current swimming warm-up strategies is needed to improve their effectiveness. The purpose of this study was to describe current precompetition warm-up practices and identify contemporary issues faced by elite swimming coaches during competition. Forty-six state-international level swimming coaches provided information through a questionnaire on their prescription of volume, intensity, and recovery within their pool and dryland-based competition warm-ups, and challenges faced during the final stages of event preparation. Coaches identified four key objectives of the precompetition warm-up: physiological (elevate body temperature and increase muscle activation), kinesthetic (tactile preparation, increase "feel" of the water), tactical (race-pace rehearsal), and mental (improve focus, reduce anxiety). Pool warm-up volume ranged from ∼1300 to 2100 m, beginning with 400-1000 m of continuous, low-intensity (∼50-70% of perceived maximal exertion) swimming, followed by 200-600 m of stroke drills and 1-2 sets (100-400 m in length) of increasing intensity (∼60-90%) swimming, concluding with 3-4 race or near race-pace efforts (25-100 m; ∼90-100%) and 100-400 m easy swimming. Dryland-based warm-up exercises, involving stretch cords and skipping, were also commonly prescribed. Coaches preferred swimmers complete their warm-up 20-30 minutes before race start. Lengthy marshalling periods (15-20+ minutes) and the time required to don racing suits (>10 minutes) were identified as complicating issues. Coaches believed that the pool warm-up affords athletes the opportunity to gain a tactile feel for the water and surrounding pool environment. The combination of dryland-based activation exercises followed by pool-based warm-up routines seems to be the preferred approach taken by elite swimming coaches preparing their athletes for competition.
Effectiveness of the Power Dry-Land Training Programmes in Youth Swimmers
Sadowski, Jerzy; Mastalerz, Andrzej; Gromisz, Wilhelm; NiŸnikowski, Tomasz
2012-01-01
The aim of the study was to evaluate the effects of the dry-land power training on swimming force, swimming performance and strength in youth swimmers. Twenty six male swimmers, free from injuries and training regularly at least 6 times a week, were enrolled in the study and randomly assigned to one of two groups: experimental (n=14, mean age 14.0 ± 0.5 yrs, mean height 1.67±0.08 m and mean body mass 55.71 ±9.55 kg) and control (n=12, mean age 14.1 ± 0.5 yrs, mean height 1.61±0.11 m and mean body mass 49.07 ±8.25 kg). The experimental group took part in a combined swimming and dry-land power training. The control group took part in swimming training only. The training programmes in water included a dominant aerobic work in front crawl. In this research the experimental group tended to present slightly greater improvements in sprint performance. However, the stroke frequency insignificantly decreased (−4.30%, p>0.05) in the experimental group and increased (6.28%, p>0.05) in the control group. The distance per stroke insignificantly increased in the experimental group (5.98%, p>0.05) and insignificantly decreased in the control group (−5.36%, p>0.05). A significant improvement of tethered swimming force for the experimental group (9.64%, p<0.02) was found, whereas the increase was not statistically significant in the control group (2.86%, p>0.05). The main data cannot clearly state that power training allowed an enhancement in swimming performance, although a tendency to improve swimming performance in tethered swimming was noticed. PMID:23486353
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2012-07-05
... 1625-AA08 Special Local Regulations for Marine Events; Potomac River, National Harbor Access Channel... special local regulations during the swim segment of the ``Swim Across the Potomac River'' swimming competition, to be held on the waters of the Potomac River on July 8, 2012. These special local regulations...
Tate, Angela; Turner, Gregory N.; Knab, Sarah E.; Jorgensen, Colbie; Strittmatter, Andrew; Michener, Lori A.
2012-01-01
Context: The prevalence of shoulder pain among competitive swimmers is high, but no guidelines exist to reduce shoulder injuries. Elucidating differences between swimmers with and without shoulder pain can serve as a basis for the development of a program to prevent shoulder injury that might lead to pain and dysfunction. Objective: To determine whether physical characteristics, exposure, or training variables differ between swimmers with and without shoulder pain or disability. Design: Cross-sectional study. Setting: Multisite swimming centers. Patients or Other Participants: A total of 236 competitive female swimmers aged 8 to 77 years. Data Collection and Analysis: Participants completed the Penn Shoulder Score and underwent testing of core endurance, range of motion, muscle force production, and pectoralis minor muscle length and the Scapular Dyskinesis Test. Swimmers were grouped by age for analysis: ages 8 to 11 years (n = 42), 12 to 14 years (n = 43), 15 to 19 years (high school, n = 84), and 23 to 77 years (masters, n = 67). Comparisons were made between groups with and without pain and disability using independent t tests for continuous data and χ2 analyses and Fisher exact tests for categorical data. Results: Nine (21.4%) swimmers aged 8 to 11 years, 8 (18.6%) swimmers aged 12 to 14 years, 19 (22.6%) high school swimmers, and 13 (19.4%) masters swimmers had shoulder pain and disability. Differences that were found in 2 or more age groups between athletes with and without shoulder pain and disability included greater swimming exposure, a higher incidence of previous traumatic injury and patient-rated shoulder instability, and reduced participation in another sport in the symptomatic groups (P < .05). Reduced shoulder flexion motion, weakness of the middle trapezius and internal rotation, shorter pectoralis minor and latissimus, participation in water polo, and decreased core endurance were found in symptomatic females in single varying age groups (P < .05). Conclusions: Female competitive swimmers have shoulder pain and disability throughout their lives. Given that exposure and physical examination findings varied between athletes with and without substantial pain and disability, a program to prevent shoulder injury that might lead to pain and dysfunction appears warranted and might include exposure reduction, cross-training, pectoral and posterior shoulder stretching, strengthening, and core endurance training. PMID:22488280
Effects of dry-land vs. resisted- and assisted-sprint exercises on swimming sprint performances.
Girold, Sébastien; Maurin, Didier; Dugué, Benoit; Chatard, Jean-Claude; Millet, Grégoire
2007-05-01
This study was undertaken to compare the effects of dry-land strength training with a combined in-water resisted- and assisted-sprint program in swimmer athletes. Twenty-one swimmers from regional to national level participated in this study. They were randomly assigned to 3 groups: the strength (S) group that was involved in a dry-land strength training program where barbells were used, the resisted- and assisted-sprint (RAS) group that got involved in a specific water training program where elastic tubes were used to generate resistance and assistance while swimming, and the control (C) group which was involved in an aerobic cycling program. During 12 weeks, the athletes performed 6 training sessions per week on separate days. All of them combined the same aerobic dominant work for their basic training in swimming and running with their specific training. Athletes were evaluated 3 times: before the training program started, after 6 weeks of training, and at the end of the training program. The outcome values were the strength of the elbow flexors and extensors evaluated using an isokinetic dynamometer, and the speed, stroke rate, stroke length, and stroke depth observed during a 50-meter sprint. No changes were observed after 6 weeks of training. At the end of the training period, we observed significant increases in swimming velocity, and strength of elbow flexors and extensors both in the S and RAS groups. However, stroke depth decreased both in the S and RAS groups. Stroke rate increased in the RAS but not in the S group. However, no significant differences in the swimming performances between the S and RAS groups were observed. No significant changes occurred in C. Altogether, programs combining swimming with dry-land strength or with in-water resisted- and assisted-sprint exercises led to a similar gain in sprint performance and are more efficient than traditional swimming training methods alone.
Sperm midpiece length predicts sperm swimming velocity in house mice.
Firman, Renée C; Simmons, Leigh W
2010-08-23
Evolutionary biologists have argued that there should be a positive relationship between sperm size and sperm velocity, and that these traits influence a male's sperm competitiveness. However, comparative analyses investigating the evolutionary associations between sperm competition risk and sperm morphology have reported inconsistent patterns of association, and in vitro sperm competition experiments have further confused the issue; in some species, males with longer sperm achieve more competitive fertilization, while in other species males with shorter sperm have greater sperm competitiveness. Few investigations have attempted to address this problem. Here, we investigated the relationship between sperm morphology and sperm velocity in house mice (Mus domesticus). We conducted in vitro sperm velocity assays on males from established selection lines, and found that sperm midpiece size was the only phenotypic predictor of sperm swimming velocity.
Reproductive-tactic-specific variation in sperm swimming speeds in a shell-brooding cichlid.
Fitzpatrick, J L; Desjardins, J K; Milligan, N; Montgomerie, R; Balshine, S
2007-08-01
Theory predicts that males experiencing elevated levels of sperm competition will invest more in gonads and produce faster-swimming sperm. Although there is ample evidence in support of the first prediction, few studies have examined sperm swimming speed in relation to sperm competition. In this study, we tested these predictions from sperm competition theory by examining sperm characteristics in Telmatochromis vittatus, a small shell-brooding cichlid fish endemic to Lake Tanganyika. Males exhibit four different reproductive tactics: pirate, territorial, satellite, and sneaker. Pirate males temporarily displace all other competing males from a shell nest, whereas sneaker males always release sperm in the presence of territorial and satellite males. Due to the fact that sneakers spawn in the presence of another male, sneakers face the highest levels of sperm competition and pirates the lowest, whereas satellites and territorials experience intermediate levels. In accordance with predictions, sperm from sneakers swam faster than sperm from males adopting the other reproductive tactics, whereas sperm from pirates was slowest. Interestingly, we were unable to detect any variation in sperm tail length among these reproductive tactics. Thus, sperm competition appears to have influenced sperm energetics in this species without having any influence on sperm size.
Warm-up and performance in competitive swimming.
Neiva, Henrique P; Marques, Mário C; Barbosa, Tiago M; Izquierdo, Mikel; Marinho, Daniel A
2014-03-01
Warm-up before physical activity is commonly accepted to be fundamental, and any priming practices are usually thought to optimize performance. However, specifically in swimming, studies on the effects of warm-up are scarce, which may be due to the swimming pool environment, which has a high temperature and humidity, and to the complexity of warm-up procedures. The purpose of this study is to review and summarize the different studies on how warming up affects swimming performance, and to develop recommendations for improving the efficiency of warm-up before competition. Most of the main proposed effects of warm-up, such as elevated core and muscular temperatures, increased blood flow and oxygen delivery to muscle cells and higher efficiency of muscle contractions, support the hypothesis that warm-up enhances performance. However, while many researchers have reported improvements in performance after warm-up, others have found no benefits to warm-up. This lack of consensus emphasizes the need to evaluate the real effects of warm-up and optimize its design. Little is known about the effectiveness of warm-up in competitive swimming, and the variety of warm-up methods and swimming events studied makes it difficult to compare the published conclusions about the role of warm-up in swimming. Recent findings have shown that warm-up has a positive effect on the swimmer's performance, especially for distances greater than 200 m. We recommend that swimmers warm-up for a relatively moderate distance (between 1,000 and 1,500 m) with a proper intensity (a brief approach to race pace velocity) and recovery time sufficient to prevent the early onset of fatigue and to allow the restoration of energy reserves (8-20 min).
García-Ramos, Amador; Padial, Paulino; de la Fuente, Blanca; Argüelles-Cienfuegos, Javier; Bonitch-Góngora, Juan; Feriche, Belén
2016-06-01
This study aimed (a) to analyze the development in the squat jump height and swimming start performance after an altitude training camp, (b) to correlate the jump height and swimming start performance before and after the altitude training period, and (c) to correlate the percent change in the squat jump height with the percent change in swimming start performance. Fifteen elite male swimmers from the Spanish Junior National Team (17.1 ± 0.8 years) were tested before and after a 17-day training camp at moderate altitude. The height reached in the squat jump exercise with additional loads of 0, 25, 50, 75, and 100% of swimmers' pretest body weight and swimming start performance (time to 5, 10, and 15 m) were the dependent variables analyzed. Significant increases in the jump height (p ≤ 0.05; effect size [ES]: 0.35-0.48) and swimming start performance (p < 0.01; ES: 0.48-0.52) after the training period were observed. The start time had similar correlations with the jump height before training (r = -0.56 to -0.77) and after training (r = -0.50 to -0.71). The change in the squat jump height was inversely correlated with the change in the start time at 5 m (r = -0.47), 10 m (r = -0.73), and 15 m (r = -0.62). These results suggest that altitude training can be suitable to enhance explosive performance. The correlations obtained between the squat jump height and start time in the raw and change scores confirm the relevance of having high levels of lower-body muscular power to optimize swimming start performance.
Hip Strength Improves Novice Surface Combat Swimming Flutterkick Performance.
Beethe, Anne Z; Nagle, Elizabeth F; Lovalekar, Mita; Nagai, Takashi; Nindl, Bradley C; Connaboy, Christopher
2018-05-29
The current study was designed to examine strength, range of motion (ROM), anthropometric, and physiological contributions to novice surface combat swimming (sCS) performance, and establish differences from freestyle swimming (FS) performance to further understand the transition of FS to sCS performance. Thirteen competitive swimmers (7 males, 6 females; 27.7±2.3 years; 176.2±2.6 cm; 75.4±3.9 kg) completed eight testing sessions consisting of the following: physiological land-based measurements for maximal anaerobic and aerobic capacity and upper and lower extremity strength and ROM, a sCS anaerobic capacity swim test measuring peak and mean force and fatigue index, two aerobic capacity tests measuring maximal aerobic capacity for both FS and sCS, and four 500m performance swims for time, one FS and three sCS. Separate multiple linear regression analysis was used to analyze predictors of both sCS and FS performance models. Freestyle swimming performance was predicted by the final FS VO 2max with a R 2 of 42.03% (F(1,10) = 7.25; p = 0.0226) whereas sCS performance was predicted by isometric hip extension peak strength with an R 2 of 41.46% (F(1,11) = 7.79; p = 0.0176). Results demonstrate different physiological characteristics predict performance, suggesting an altered strategy is utilized for novice sCS than FS. It is suggested this may be due to the added constraints as mandated by mission requirements including boots, weighted gear, and clandestine requirements with hips lowered beneath the surface. Further research should examine the kinematics of the sCS flutterkick to improve performance by developing training strategies specific for the task.
76 FR 53824 - Safety Zone; 2011 Rohto Ironman 70.3 Miami, Biscayne Bay, Miami, FL
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2011-08-30
... public during the 1.2 mile swim portion of this competition. Persons and vessels are prohibited from... protect race participants, participant vessels, and the general public during the 1.2 mile swim portion of... Rohto Ironman 70.3 Miami. This event includes a 1.2 mile swim, which will take place on the waters of...
Electromyography in the four competitive swimming strokes: a systematic review.
Martens, Jonas; Figueiredo, Pedro; Daly, Daniel
2015-04-01
The aim of this paper is to give an overview on 50 years of research in electromyography in the four competitive swimming strokes (crawl, breaststroke, butterfly, and backstroke). A systematic search of the existing literature was conducted using the combined keywords "swimming" and "EMG" on studies published before August 2013, in the electronic databases PubMed, ISI Web of Knowledge, SPORT discus, Academic Search Elite, Embase, CINAHL and Cochrane Library. The quality of each publication was assessed by two independent reviewers using a custom made checklist. Frequency of topics, muscles studied, swimming activities, populations, types of equipment and data treatment were determined from all selected papers and, when possible, results were compared and contrasted. In the first 20 years of EMG studies in swimming, most papers were published as congress proceedings. The methodological quality was low. Crawl stroke was most often studied. There was no standardized manner of defining swimming phases, normalizing the data or of presenting the results. Furthermore, the variability around the mean muscle activation patterns is large which makes it difficult to define a single pattern applicable to all swimmers in any activity examined. Copyright © 2014 Elsevier Ltd. All rights reserved.
First-rib stress fracture in two adolescent swimmers: a case report.
Low, Sara; Kern, Michael; Atanda, Alfred
2016-01-01
First-rib stress fractures have been described in adolescent athletes in various sports, with only one prior case report of first-rib stress fractures in an adolescent female swimmer. There is a need for research on the cause, management, and prevention of these injuries as they lead to significant morbidity and critical time away from sport for these aspiring athletes. We aimed to describe first-rib stress fractures as a potential cause for non-specific atraumatic chronic shoulder pain in adolescent swimmers and to discuss the different presentations, unique risk factors, treatment, and potential injury prevention strategies of such fractures. We discussed two such cases which were successfully treated with activity modification with restriction of all overhead activity, gradually progressive physical therapy and a return to swimming protocol. First-rib stress fractures can vary in presentation and should be in the differential diagnosis in adolescent swimmers with chronic shoulder pain. These injuries can be successfully managed with rest from overhead activities and physical therapy. Gradual return to competitive swimming can be achieved even with non-union of a first-rib stress fracture. Emphasis on balanced strength training in different muscle groups and proper swimming technique is essential to prevent these injuries.
Synchronized Swimming--The Training at Squaw Valley.
ERIC Educational Resources Information Center
Swan, Margaret M.
1979-01-01
The Olympic Training Center at Squaw Valley is available to individuals and groups interested in advanced skill development. It offers training in sports and sports medicine techniques. Its use by the Olympic synchronized swimming team is highlighted. (JMF)
García-Pinillos, Felipe; Cámara-Pérez, Jose C; Soto-Hermoso, Víctor M; Latorre-Román, Pedro Á
2017-01-01
García-Pinillos, F, Cámara-Pérez, JC, Soto-Hermoso, VM, and Latorre-Román, PÁ. A High Intensity Interval Training (HIIT)-based running plan improves athletic performance by improving muscle power. J Strength Cond Res 31(1): 146-153, 2017-This study aimed to examine the effect of a 5-week high-intensity intermittent training (HIIT)-based running plan on athletic performance and to compare the physiological and neuromuscular responses during a sprint-distance triathlon before and after the HIIT period. Thirteen triathletes were matched into 2 groups: the experimental group (EG) and the control group (CG). The CG was asked to maintain their normal training routines, whereas the EG maintained only their swimming and cycling routines and modified their running routine. Participants completed a sprint-distance triathlon before (pretest) and after (posttest) the intervention period. In both pretest and posttest, the participants performed 4 jumping tests: before the race (baseline), postswim, postcycling, and postrun. Additionally, heart rate was monitored (HRmean), whereas rate of perceived exertion (RPE) and blood lactate accumulation (BLa) were registered after the race. No significant differences (p ≥ 0.05) between groups were found before HIIT intervention (at pretest). Significant group-by-training interactions were found in vertical jumping ability and athletic performance: the EG improved jumping performance (∼6-9%, p ≤ 0.05, effect size (ES) > 0.7), swimming performance (p = 0.013, ES = 0.438), and running time (p = 0.001, ES = 0.667) during the competition, whereas the CG remained unchanged (p ≥ 0.05, ES < 0.4). No changes (p ≥ 0.05, ES < 0.4) were observed in RPE, HRmean, and BLa. A linear regression analysis showed that ΔCMJ predicted both the ΔRu_time (R = 0.559; p = 0.008) and the ΔOverall_time (R = 0.391; p = 0.048). This low-volume, HIIT-based running plan combined with the high training volumes of these triathletes in swimming and cycling improved athletic performance during a sprint-distance triathlon. This improvement may be due to improved neuromuscular characteristics that were transferred into improved muscle power and work economy.
Fiaz, Ansa W.; Léon-Kloosterziel, Karen M.; Gort, Gerrit; Schulte-Merker, Stefan; van Leeuwen, Johan L.; Kranenbarg, Sander
2012-01-01
Fish larvae experience many environmental challenges during development such as variation in water velocity, food availability and predation. The rapid development of structures involved in feeding, respiration and swimming increases the chance of survival. It has been hypothesized that mechanical loading induced by muscle forces plays a role in prioritizing the development of these structures. Mechanical loading by muscle forces has been shown to affect larval and embryonic bone development in vertebrates, but these investigations were limited to the appendicular skeleton. To explore the role of mechanical load during chondrogenesis and osteogenesis of the cranial, axial and appendicular skeleton, we subjected zebrafish larvae to swim-training, which increases physical exercise levels and presumably also mechanical loads, from 5 until 14 days post fertilization. Here we show that an increased swimming activity accelerated growth, chondrogenesis and osteogenesis during larval development in zebrafish. Interestingly, swim-training accelerated both perichondral and intramembranous ossification. Furthermore, swim-training prioritized the formation of cartilage and bone structures in the head and tail region as well as the formation of elements in the anal and dorsal fins. This suggests that an increased swimming activity prioritized the development of structures which play an important role in swimming and thereby increasing the chance of survival in an environment where water velocity increases. Our study is the first to show that already during early zebrafish larval development, skeletal tissue in the cranial, axial and appendicular skeleton is competent to respond to swim-training due to increased water velocities. It demonstrates that changes in water flow conditions can result into significant spatio-temporal changes in skeletogenesis. PMID:22529905
Self selected speed and maximal lactate steady state speed in swimming.
Baron, B; Dekerle, J; Depretz, S; Lefevre, T; Pelayo, P
2005-03-01
The purposes of this study were to ascertain whether physiological and stroking parameters remain stable during a 2-hour exercise performed at self-selected swimming speed (S4) and whether this speed corresponds to those associated with the maximal lactate steady state (SMLSS). Ten well-trained competitive swimmers performed a maximal 400-m front crawl test, 4 30-min swimming tests in order to determine S(MLSS) and a 2-hour test swum at their preferred paces to determine self-selected swimming speed (S4), stroke rate (SR4), and stroke length (SL4) defined as the mean values observed between the 5th and the 15th min of this test. The stroking, metabolic and respiratory parameters, and ratings of perceived exertion (CR10) were reported throughout the 2-hour test. S4 and SMLSS were not significantly different and were highly correlated (r=0.891). S4 and SL4 decreased significantly after a steady state of 68 min and 100 min, respectively, whereas SR4 remained constant. Mean VO2, dioxide output, and heart rate values did not evolve significantly between the 10th and 120th minute of the test whereas capillary blood lactate concentration (La) decreased significantly (p<0.05). Moreover, respiratory CR10 did not evolve significantly between the 10th and the 120th minute of the test whereas general CR10 and muscular CR10 increased significantly. Considering the (La), SL4 and CR10 values variations, muscular parameters and a probably glycogenic depletion seem to be the main limiting factors that prevent maintaining the self selected swimming speed.
Alkatan, Mohammed; Baker, Jeffrey R; Machin, Daniel R; Park, Wonil; Akkari, Amanda S; Pasha, Evan P; Tanaka, Hirofumi
2016-03-01
Arthritis and its associated joint pain act as significant barriers for adults attempting to perform land-based physical activity. Swimming can be an ideal form of exercise for patients with arthritis. Yet there is no information on the efficacy of regular swimming exercise involving patients with arthritis. The effect of a swimming exercise intervention on joint pain, stiffness, and physical function was evaluated in patients with osteoarthritis (OA). Using a randomized study design, 48 sedentary middle-aged and older adults with OA underwent 3 months of either swimming or cycling exercise training. Supervised exercise training was performed for 45 min/day, 3 days/week at 60-70% heart rate reserve for 12 weeks. The Western Ontario and McMaster Universities Arthritis Index was used to measure joint pain, stiffness, and physical limitation. After the exercise interventions, there were significant reductions in joint pain, stiffness, and physical limitation accompanied by increases in quality of life in both groups (all p < 0.05). Functional capacity as assessed by maximal handgrip strength, isokinetic knee extension and flexion power (15-30% increases), and the distance covered in the 6-min walk test increased (all p < 0.05) in both exercise groups. No differences were observed in the magnitude of improvements between swimming and cycling training. Regular swimming exercise reduced joint pain and stiffness associated with OA and improved muscle strength and functional capacity in middle-aged and older adults with OA. Additionally, the benefits of swimming exercise were similar to the more frequently prescribed land-based cycling training. clinicaltrials.gov NCT01836380.
Disease resistance is related to inherent swimming performance in Atlantic salmon.
Castro, Vicente; Grisdale-Helland, Barbara; Jørgensen, Sven M; Helgerud, Jan; Claireaux, Guy; Farrell, Anthony P; Krasnov, Aleksei; Helland, Ståle J; Takle, Harald
2013-01-21
Like humans, fish can be classified according to their athletic performance. Sustained exercise training of fish can improve growth and physical capacity, and recent results have documented improved disease resistance in exercised Atlantic salmon. In this study we investigated the effects of inherent swimming performance and exercise training on disease resistance in Atlantic salmon.Atlantic salmon were first classified as either poor or good according to their swimming performance in a screening test and then exercise trained for 10 weeks using one of two constant-velocity or two interval-velocity training regimes for comparison against control trained fish (low speed continuously). Disease resistance was assessed by a viral disease challenge test (infectious pancreatic necrosis) and gene expression analyses of the host response in selected organs. An inherently good swimming performance was associated with improved disease resistance, as good swimmers showed significantly better survival compared to poor swimmers in the viral challenge test. Differences in mortalities between poor and good swimmers were correlated with cardiac mRNA expression of virus responsive genes reflecting the infection status. Although not significant, fish trained at constant-velocity showed a trend towards higher survival than fish trained at either short or long intervals. Finally, only constant training at high intensity had a significant positive effect on fish growth compared to control trained fish. This is the first evidence suggesting that inherent swimming performance is associated with disease resistance in fish.
Rebutini, Vanessa Z; Pereira, Gleber; Bohrer, Roberta C D; Ugrinowitsch, Carlos; Rodacki, André L F
2016-09-01
Rebutini, VZ, Pereira, G, Bohrer, RCD, Ugrinowitsch, C, and Rodacki, ALF. Plyometric long jump training with progressive loading improves kinetic and kinematic swimming start parameters. J Strength Cond Res 30(9): 2392-2398, 2016-This study was aimed to determine the effects of a plyometric long jump training program on torque around the lower limb joints and kinetic and kinematics parameters during the swimming jump start. Ten swimmers performed 3 identical assessment sessions, measuring hip and knee muscle extensors during maximal voluntary isometric contraction and kinetic and kinematics parameters during the swimming jump start, at 3 instants: INI (2 weeks before the training program, control period), PRE (2 weeks after INI measurements), and POST (24-48 hours after 9 weeks of training). There were no significant changes from INI to PRE measurements. However, the peak torque and rate of torque development increased significantly from PRE to POST measurements for both hip (47 and 108%) and knee (24 and 41%) joints. There were significant improvements to the horizontal force (7%), impulse (9%), and angle of resultant force (19%). In addition, there were significant improvements to the center of mass displacement (5%), horizontal takeoff velocity (16%), horizontal velocity at water entrance (22%), and peak angle velocity for the knee (15%) and hip joints (16%). Therefore, the plyometric long jump training protocol was effective to enhance torque around the lower limb joints and to control the resultant vector direction, to increase the swimming jump start performance. These findings suggest that coaches should use long jump training instead of vertical jump training to improve swimming start performance.
2012-01-01
Background This study aimed to examine the effects of intermittent and continuous swimming training on muscle protein metabolism in neonatal alloxan-administered rats. Methods Wistar rats were used and divided into six groups: sedentary alloxan (SA), sedentary control (SC), continuous trained alloxan (CA), intermittent trained alloxan (IA), continuous trained control (CC) and intermittent trained control (IC). Alloxan (250 mg/kg body weight) was injected into newborn rats at 6 days of age. The continuous training protocol consisted of 12 weeks of swimming training in individual cylinder tanks while supporting a load that was 5% of body weight; uninterrupted swimming for 1 h/day, five days a week. The intermittent training protocol consisted of 12 weeks of swimming training in individual cylinder tanks while supporting a load that was 15% of body weight; 30 s of activity interrupted by 30 s of rest for a total of 20 min/day, five days a week. Results At 28 days, the alloxan animals displayed higher glycemia after glucose overload than the control animals. No differences in insulinemia among the groups were detected. At 120 days, no differences in serum albumin and total protein among the groups were observed. Compared to the other groups, DNA concentrations were higher in the alloxan animals that were subjected to continuous training, whereas the DNA/protein ratio was higher in the alloxan animals that were subjected to intermittent training. Conclusion It was concluded that continuous and intermittent training sessions were effective in altering muscle growth by hyperplasia and hypertrophy, respectively, in alloxan-administered animals. PMID:22309804
Rejman, Marek; Bilewski, Marek; Szczepan, Stefan; Klarowicz, Andrzej; Rudnik, Daria; Maćkała, Krzysztof
2017-01-01
The aim of this study was to analyse changes taking place within selected kinematic parameters of the swimming start, after completing a six-week plyometric training, assuming that the take-off power training improves its effectiveness. The experiment included nine male swimmers. In the pre-test the swimmers performed three starts focusing on the best performance. Next, a plyometric training programme, adapted from sprint running, was introduced in order to increase a power of the lower extremities. The programme entailed 75 minute sessions conducted twice a week. Afterwards, a post-test was performed, analogous to the pre-test. Spatio-temporal structure data of the swimming start were gathered from video recordings of the swimmer above and under water. Impulses triggered by the plyometric training contributed to a shorter start time (the main measure of start effectiveness) and glide time as well as increasing average take-off, flight and glide velocities including take-off, entry and glide instantaneous velocities. The glide angle decreased. The changes in selected parameters of the swimming start and its confirmed diagnostic values, showed the areas to be susceptible to plyometric training and suggested that applied plyometric training programme aimed at increasing take-off power enhances the effectiveness of the swimming start.
Li, Jiang-Hua; Wang, Zhi-Hui; Zhu, Xiao-Juan; Deng, Zhao-Hui; Cai, Can-Xin; Qiu, Li-Qiang; Chen, Wei; Lin, Ya-Jun
2015-01-01
Chlorination is the most popular method for disinfecting swimming pool water; however, although pathogens are being killed, many toxic compounds, called disinfection by-products (DBPs), are formed. Numerous epidemiological publications have associated the chlorination of pools with dysfunctions of the respiratory system and with some other diseases. However, the findings concerning these associations are not always consistent and have not been confirmed by toxicological studies. Therefore, the health effects from swimming in chlorinated pools and the corresponding stress reactions in organisms are unclear. In this study, we show that although the growth and behaviors of experimental rats were not affected, their health, training effects and metabolic profiles were significantly affected by a 12-week swimming training program in chlorinated water identical to that of public pools. Interestingly, the eyes and skin are the organs that are more directly affected than the lungs by the irritants in chlorinated water; instead of chlorination, training intensity, training frequency and choking on water may be the primary factors for lung damage induced by swimming. Among the five major organs (the heart, liver, spleen, lungs and kidneys), the liver is the most likely target of DBPs. Through metabolomics analysis, the corresponding metabolic stress pathways and a defensive system focusing on taurine were presented, based on which the corresponding countermeasures can be developed for swimming athletes and for others who spend a lot of time in chlorinated swimming pools. PMID:25742134
The Effect of an Altitude Training Camp on Swimming Start Time and Loaded Squat Jump Performance
Štirn, Igor; Padial, Paulino; Argüelles-Cienfuegos, Javier; De la Fuente, Blanca; Calderón, Carmen; Bonitch-Góngora, Juan; Tomazin, Katja; Strumbelj, Boro; Strojnik, Vojko; Feriche, Belén
2016-01-01
This study evaluated the influence of an altitude training (AT) camp on swimming start time and loaded squat jump performance. To accomplish this goal, 13 international swimmers (8 women, 5 men) were allocated to both the control (Sea Level Training, SLT) and experimental conditions (AT, 2320 m above sea level) that were separated by a one year period. All tests (15 m freestyle swimming start and loaded squat jumps with additional loads of 25%, 50%, 75%, and 100% of swimmers’ body weight) were performed before and after a concurrent 3-week strength and endurance training program prescribed by the national coach. Following the SLT camp, significant impairments in swimming start times to 10 (+3.1%) and 15 m (+4.0%) were observed (P < 0.05), whereas no significant changes for the same distances were detected following the AT camp (-0.89%; P > 0.05). Trivial changes in peak velocity were obtained during the loaded squat jump after both training periods (effect sizes: < 0.20). Based on these results we can conclude that a traditional training high—living high strategy concurrent training of 3 weeks does not adversely affect swimming start time and loaded squat jump performance in high level swimmers, but further studies are necessary to assess the effectiveness of power-oriented resistance training in the development of explosive actions. PMID:27467760
Epidemiology of Injuries and Prevention Strategies in Competitive Swimmers
Wanivenhaus, Florian; Fox, Alice J. S.; Chaudhury, Salma; Rodeo, Scott A.
2012-01-01
Context: Competitive swimmers are predisposed to musculoskeletal injuries of the upper limb, knee, and spine. This review discusses the epidemiology of these injuries, in addition to prevention strategies that may assist the physician in formulating rehabilitation programs for the swimmer following an injury. Evidence Acquisition: A literature search was performed by a review of Google Scholar, OVID, and PubMed articles published from 1972 to 2011. Results: This study highlights the epidemiology of injuries common to competitive swimmers and provides prevention strategies for the sports health professional. Conclusions: An understanding of swimming biomechanics and typical injuries in swimming aids in early recognition of injury, initiation of treatment, and design of optimal prevention and rehabilitation strategies. PMID:23016094
Tourmente, Maximiliano; Villar-Moya, Pilar; Varea-Sánchez, María; Luque-Larena, Juan J; Rial, Eduardo; Roldan, Eduardo R S
2015-09-01
Sperm viability, acrosome integrity, motility, and swimming velocity are determinants of male fertility and exhibit an extreme degree of variation among closely related species. Many of these sperm parameters are associated with sperm ATP content, which has led to predictions of trade-offs between ATP content and sperm motility and velocity. Selective pressures imposed by sperm competition have been proposed as evolutionary causes of this pattern of diversity in sperm traits. Here, we examine variation in sperm viability, acrosome integrity, motility, swimming velocity, and ATP content over time, among 18 species of closely related muroid rodents, to address the following questions: (a) Do sperm from closely related species vary in ATP content after a period of incubation? (b) Are these differences in ATP levels related to differences in other sperm traits? (c) Are differences in ATP content and sperm performance over time explained by the levels of sperm competition in these species? Our results revealed a high degree of interspecific variability in changes in sperm ATP content, acrosome integrity, sperm motility and swimming velocity over time. Additionally, species with high sperm competition levels were able to maintain higher levels of sperm motility and faster sperm swimming velocity when they were incubated under conditions that support sperm survival. Furthermore, we show that the maintenance of such levels of sperm performance is correlated with the ability of sperm to sustain high concentrations of intracellular ATP over time. Thus, sperm competition may have an important role maximizing sperm metabolism and performance and, ultimately, the fertilizing capacity of spermatozoa. © 2015 by the Society for the Study of Reproduction, Inc.
Level of Interleukins IL-6 and IL-15 in Blood Plasma of Mice after Forced Swimming Test.
Kapilevich, L V; Kironenko, T A; Zakharova, A N; Kabachkova, A V; Orlov, S N
2017-05-01
We measured the concentrations of IL-6 and IL-15 in blood plasma of mice at different terms after forced swimming, taking into account exercise intensity and preliminary training. It was shown that training was an important factor affecting blood plasma level of IL both at rest and after single forced swimming: in trained animals, the concentration of both myokines increased immediately after swimming, while in untrained animals, this increase was observed only after 5 h. Changes in cytokine production against the background of training can be associated with various factors, including neuroendocrine mechanisms, stress, modification of intracellular signaling, as well as reorganization of transcriptional mechanisms in muscle fibers. The most important factor is shift in the ratio of monovalent cations (sodium and potassium) in the cytoplasm.
Disease resistance is related to inherent swimming performance in Atlantic salmon
2013-01-01
Background Like humans, fish can be classified according to their athletic performance. Sustained exercise training of fish can improve growth and physical capacity, and recent results have documented improved disease resistance in exercised Atlantic salmon. In this study we investigated the effects of inherent swimming performance and exercise training on disease resistance in Atlantic salmon. Atlantic salmon were first classified as either poor or good according to their swimming performance in a screening test and then exercise trained for 10 weeks using one of two constant-velocity or two interval-velocity training regimes for comparison against control trained fish (low speed continuously). Disease resistance was assessed by a viral disease challenge test (infectious pancreatic necrosis) and gene expression analyses of the host response in selected organs. Results An inherently good swimming performance was associated with improved disease resistance, as good swimmers showed significantly better survival compared to poor swimmers in the viral challenge test. Differences in mortalities between poor and good swimmers were correlated with cardiac mRNA expression of virus responsive genes reflecting the infection status. Although not significant, fish trained at constant-velocity showed a trend towards higher survival than fish trained at either short or long intervals. Finally, only constant training at high intensity had a significant positive effect on fish growth compared to control trained fish. Conclusions This is the first evidence suggesting that inherent swimming performance is associated with disease resistance in fish. PMID:23336751
The effects of intensity on V̇O2 kinetics during incremental free swimming.
de Jesus, Kelly; Sousa, Ana; de Jesus, Karla; Ribeiro, João; Machado, Leandro; Rodríguez, Ferran; Keskinen, Kari; Vilas-Boas, João Paulo; Fernandes, Ricardo J
2015-09-01
Swimming and training are carried out with wide variability in distances and intensities. However, oxygen uptake kinetics for the intensities seen in swimming has not been reported. The purpose of this study was to assess and compare the oxygen uptake kinetics throughout low-moderate to severe intensities during incremental swimming exercise. We hypothesized that the oxygen uptake kinetic parameters would be affected by swimming intensity. Twenty male trained swimmers completed an incremental protocol of seven 200-m crawl swims to exhaustion (0.05 m·s(-1) increments and 30-s intervals). Oxygen uptake was continuously measured by a portable gas analyzer connected to a respiratory snorkel and valve system. Oxygen uptake kinetics was assessed using a double exponential regression model that yielded both fast and slow components of the response of oxygen uptake to exercise. From low-moderate to severe swimming intensities changes occurred for the first and second oxygen uptake amplitudes (P ≤ 0.04), time constants (P = 0.01), and time delays (P ≤ 0.02). At the heavy and severe intensities, a notable oxygen uptake slow component (>255 mL·min(-1)) occurred in all swimmers. Oxygen uptake kinetics whilst swimming at different intensities offers relevant information regarding cardiorespiratory and metabolic stress that might be useful for appropriate performance diagnosis and training prescription.
Veliz, Rafael R; Suarez-Arrones, Luis; Requena, Bernardo; Haff, G Gregory; Feito, Javier; Sáez de Villarreal, Eduardo
2015-02-01
We examined the effect of 16 weeks of lower-body resistance and power-oriented training on key performance measures of elite female water polo players. Twenty-one players were randomly assigned to 2 groups: control group (C) who did in-water training only and a lower body strength (LBS) group, who performed resistance (full squat and split squat) and jump and power-oriented lower-body training (countermovement jump [CMJ] loaded and CMJ) sessions (twice per week) in addition to the same in-water training. In-water training was conducted 5 days per week for a total of 16 weeks. Twenty-meter maximal sprint swim (MSS), lower-body strength during 1 repetition maximum (1RM) full squat (FS), in-water boost and CMJ, and Throwing speed (ThS) were measured before and after the training. Pretraining results showed no statistically significant differences between the groups in any of the variables tested. After 16 weeks, no statistically significant improvement was found in any of the variables measured in the C group, however, significant improvement was found in the LBS group: in-water boost (4.6 cm, 12.02%, effect size [ES] = 1.02), CMJ (2.4 cm, 8.66%, ES = 0.85), FS (12.7 kg, 20.99%, ES = 2.41), and ThS (3.4 km·h, 6.86%, ES = 3.44). Lower-body resistance and power-oriented training in female water polo players for 16 weeks produced significant improvements in performance qualities highly specific to water polo performance. Therefore, we propose modifications to current training methodology for female water polo players to include resistance and power-oriented training during the competitive season in this sport.
Incremental exercise test for the evaluation of peak oxygen consumption in paralympic swimmers.
de Souza, Helton; DA Silva Alves, Eduardo; Ortega, Luciana; Silva, Andressa; Esteves, Andrea M; Schwingel, Paulo A; Vital, Roberto; DA Rocha, Edilson A; Rodrigues, Bruno; Lira, Fabio S; Tufik, Sergio; DE Mello, Marco T
2016-04-01
Peak oxygen consumption (VO2peak) is a fundamental parameter used to evaluate physical capacity. The objective of this study was to explore two types of incremental exercise tests used to determine VO2peak in four Paralympic swimmers: arm ergometer testing in the laboratory and testing in the swimming pool. On two different days, the VO2peak values of the four athletes were measured in a swimming pool and by a cycle ergometer. The protocols identified the VO2peak by progressive loading until the volitional exhaustion maximum was reached. The results were analyzed using the paired Student's t-test, Cohen's d effect sizes and a linear regression. The results showed that the VO2peak values obtained using the swimming pool protocol were higher (P=0.02) than those obtained by the arm ergometer (45.8±19.2 vs. 30.4±15.5; P=0.02), with a large effect size (d=3.20). When analyzing swimmers 1, 2, 3 and 4 individually, differences of 22.4%, 33.8%, 60.1% and 27.1% were observed, respectively. Field tests similar to the competitive setting are a more accurate way to determine the aerobic capacity of Paralympic swimmers. This approach provides more sensitive data that enable better direction of training, consequently facilitating improved performance.
The reliability of an instrumented start block analysis system.
Tor, Elaine; Pease, David L; Ball, Kevin A
2015-02-01
The swimming start is highly influential to overall competition performance. Therefore, it is paramount to develop reliable methods to perform accurate biomechanical analysis of start performance for training and research. The Wetplate Analysis System is a custom-made force plate system developed by the Australian Institute of Sport--Aquatic Testing, Training and Research Unit (AIS ATTRU). This sophisticated system combines both force data and 2D digitization to measure a number of kinetic and kinematic parameter values in an attempt to evaluate start performance. Fourteen elite swimmers performed two maximal effort dives (performance was defined as time from start signal to 15 m) over two separate testing sessions. Intraclass correlation coefficients (ICC) were used to determine each parameter's reliability. The kinetic parameters all had ICC greater than 0.9 except the time of peak vertical force (0.742). This may have been due to variations in movement initiation after the starting signal between trials. The kinematic and time parameters also had ICC greater than 0.9 apart from for the time of maximum depth (0.719). This parameter was lower due to the swimmers varying their depth between trials. Based on the high ICC scores for all parameters, the Wetplate Analysis System is suitable for biomechanical analysis of swimming starts.
Habibi, Parisa; Alihemmati, Alireza; NourAzar, Alireza; Yousefi, Hadi; Mortazavi, Safieh; Ahmadiasl, Nasser
2016-04-01
The beneficial and more potent role of exercise to prevent heart apoptosis in ovariectomized rats has been known. The aim of this study was to examine the effects of swimming training on cardiac expression of Bcl-2, and Mir-133 levels and glycogen changes in the myocyte. Forty animals were separated into four groups as control, sham, ovariectomy (OVX) and ovariectomized group with 8 weeks swimming training (OVX.E). Training effects were evaluated by measuring lipid profiles, Bcl-2 and Mir-133 expression levels in the cardiac tissue. Grafts were analyzed by reverse transcription-polymerase chain reaction for Bcl-2 mRNA and Mir-133 and by Western blot for Bcl-2 protein. Ovariectomy down-regulated Bcl-2 and Mir-133 expression levels in the cardiac tissue, and swimming training up-regulated their expression significantly (P<0.05). Our results showed that regular exercise as a physical replacement therapy could prevent and improve the effects of estrogen deficiency in the cardia.
Effect of endurance swimming on rat cardiac myofibrillar ATPase with experimental diabetes.
Belcastro, A N; Maybank, P; Rossiter, M; Secord, D
1985-09-01
Diabetes is characterized by depressed cardiac functional properties attributed to Ca2+-activated ATPase activity. In contrast, endurance swimming enhances the cardiac functional properties and Ca2+-activated myofibril ATPase. Thus, the purpose of this study was to observe if the changes associated with experimental diabetes can be ameliorated with training. Diabetes was induced with a single i.v. injection of streptozotocin (60 mg/kg). Blood and urine glucose concentrations were 802 +/- 44 and 6965 +/- 617 mg/dL, respectively. The training control and training diabetic animals were made to swim (+/- 2% body weight) 4 days/week for 8 weeks. Cardiac myofibril, at 10 microM free Ca2+ concentration was reduced by 54% in the sedentary diabetics compared with sedentary control animals (p less than 0.05). Swim training enhanced the Ca2+-activated myofibril ATPase activities for the normal animals. The diabetic animals, which swam for 8 weeks, had further reduced their Ca2+-activated myofibril ATPase activity when compared with sedentary diabetics (p less than 0.05). Similarly, the Mg2+-stimulated myofibril ATPase activity was depressed by 31% in diabetics following endurance swimming. It is concluded that the depressed Ca2+-activated myofibril ATPase activity of diabetic hearts is not reversible with endurance swimming.
Swimming training prevents metabolic imprinting induced by hypernutrition during lactation.
Fischer, Stefani Valeria; Capriglioni Cancian, Cláudia Regina; Montes, Elisangela Gueiber; de Carvalho Leite, Nayara; Grassiolli, Sabrina
2015-02-01
Reduction in litter size during lactation induces hypernutrition of the offspring culminating with altered metabolic programming during adult life. Overnourished rats present alterations in the endocrine pancreas and major predisposition to the development of type 2 diabetes. Our study evaluated the impact of swimming training on insulin secretion control in overnourished rats. At postnatal day 3 male rat pup litters were redistributed randomly into Small Litters (SL, 3 pups) or Normal Litters (NL, 9 pups) to induce early overfeeding during lactation. Both groups were subjected to swimming training (3 times/week/30 min) post-weaning (21 days) for 72 days. At 92 days of life pancreatic islets were isolated using collagenase technique and incubated with glucose in the presence or absence of acetylcholine (Ach, 0.1-1000 μM) or glucagon-like peptide 1 (GLP1, 10 nM). Adipose tissue depots (white and brown) and endocrine pancreas samples were examined by histological analysis. Food intake and body weight were measured. Blood biochemical parameters were also evaluated. Swimming training prevented metabolic program alteration by hypernutrition during lactation. Exercise reduced obesity and hyperglycemia in overnourished rats. Pancreatic islets isolated from overnourished rats showed a reduction in glucose-induced insulin secretion and cholinergic responses while the insulinotropic action of GLP1 was increased. Physical training effectively restored glucose-induced insulin secretion and GLP1-stimulated action in pancreatic islets from overnourished rats. However, swimming training did not correct the weak cholinergic response in pancreatic islets isolated from overnourished rats. Swimming training avoids obesity development, corrects glucose-induced insulin secretion, as well as, GLP1 insulinotropic response in overnourished rats. Copyright © 2014 European Society for Clinical Nutrition and Metabolism. Published by Elsevier Ltd. All rights reserved.
ERIC Educational Resources Information Center
Vlasich, Cynthia
1989-01-01
Six new aquatic courses, developed by the Red Cross, are described. They are: Infant and Preschool Aquatics, Longfellow's Whale Tales (classroom water safety lessons for K-Six), Basic Water Safety, Emergency Water Safety, Lifeguard Training, and Safety Training for Swim Coaches. (IAH)
Wu, Hao; Jin, Meihua; Han, Donghe; Zhou, Mingsheng; Mei, Xifan; Guan, Youfei; Liu, Chang
2015-03-20
This study aimed to investigate the mechanism by which aerobic swimming training prevents high-fat-diet-induced nonalcoholic fatty liver disease (NAFLD). Forty-two male C57BL/6 mice were randomized into normal-diet sedentary (ND; n = 8), ND exercised (n = 8), high-fat diet sedentary (HFD; n = 13), and HFD exercised groups (n = 13). After 2 weeks of training adaptation, the mice were subjected to an aerobic swimming protocol (60 min/day) 5 days/week for 10 weeks. The HFD group exhibited significantly higher mRNA levels of fatty acid transport-, lipogenesis-, and β-oxidation-associated gene expressions than the ND group. PANDER and FOXO1 expressions increased, whereas AKT expression decreased in the HFD group. The aerobic swimming program with the HFD reversed the effects of the HFD on the expressions of thrombospondin-1 receptor, liver fatty acid-binding protein, long-chain fatty-acid elongase-6, Fas cell surface death receptor, and stearoyl-coenzyme A desaturase-1, as well as PANDER, FOXO1, and AKT. In the HFD exercised group, PPARα and AOX expressions were much higher. Our findings suggest that aerobic swimming training can prevent NAFLD via the regulation of fatty acid transport-, lipogenesis-, and β-oxidation-associated genes. In addition, the benefits from aerobic swimming training were achieved partly through the PANDER-AKT-FOXO1 pathway. Copyright © 2015 Elsevier Inc. All rights reserved.
Terada, Shin; Tabata, Izumi; Higuchi, Mitsuru
2004-02-01
We previously reported that high-intensity exercise training significantly increased citrate synthase (CS) activity, a marker of oxidative enzyme, in rat skeletal muscle to a level equaling that attained after low-intensity prolonged exercise training (Terada et al., J Appl Physiol 90: 2019-2024, 2001). Since mitochondrial oxidative enzymes and fatty acid oxidation (FAO) enzymes are often increased simultaneously, we assessed the effect of high-intensity intermittent swimming training on FAO enzyme activity in rat skeletal muscle. Male Sprague-Dawley rats (3 to 4 weeks old) were assigned to a 10-day period of high-intensity intermittent exercise training (HIT), low-intensity prolonged exercise training (LIT), or sedentary control conditions. In the HIT group, the rats repeated fourteen 20 s swimming sessions with a weight equivalent to 14-16% of their body weight. Between the exercise sessions, a 10 s pause was allowed. Rats in the LIT group swam 6 h/day in two 3 h sessions separated by 45 min of rest. CS activity in the triceps muscle of rats in the HIT and LIT groups was significantly higher than that in the control rats by 36 and 39%, respectively. Furthermore, 3-beta hydroxyacyl-CoA dehydrogenase (HAD) activity, an important enzyme in the FAO pathway in skeletal muscle, was higher in the two training groups than in the control rats (HIT: 100%, LIT: 88%). No significant difference in HAD activity was observed between the two training groups. In conclusion, the present investigation demonstrated that high-intensity intermittent swimming training elevated FAO enzyme activity in rat skeletal muscle to a level similar to that attained after 6 h of low-intensity prolonged swimming exercise training.
Controlled-frequency breath swimming improves swimming performance and running economy.
Lavin, K M; Guenette, J A; Smoliga, J M; Zavorsky, G S
2015-02-01
Respiratory muscle fatigue can negatively impact athletic performance, but swimming has beneficial effects on the respiratory system and may reduce susceptibility to fatigue. Limiting breath frequency during swimming further stresses the respiratory system through hypercapnia and mechanical loading and may lead to appreciable improvements in respiratory muscle strength. This study assessed the effects of controlled-frequency breath (CFB) swimming on pulmonary function. Eighteen subjects (10 men), average (standard deviation) age 25 (6) years, body mass index 24.4 (3.7) kg/m(2), underwent baseline testing to assess pulmonary function, running economy, aerobic capacity, and swimming performance. Subjects were then randomized to either CFB or stroke-matched (SM) condition. Subjects completed 12 training sessions, in which CFB subjects took two breaths per length and SM subjects took seven. Post-training, maximum expiratory pressure improved by 11% (15) for all 18 subjects (P < 0.05) while maximum inspiratory pressure was unchanged. Running economy improved by 6 (9)% in CFB following training (P < 0.05). Forced vital capacity increased by 4% (4) in SM (P < 0.05) and was unchanged in CFB. These findings suggest that limiting breath frequency during swimming may improve muscular oxygen utilization during terrestrial exercise in novice swimmers. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Psychophysiological evidence for the genuineness of swimming-style colour synaesthesia.
Rothen, Nicolas; Nikolić, Danko; Jürgens, Uta Maria; Mroczko-Wąsowicz, Aleksandra; Cock, Josephine; Meier, Beat
2013-03-01
Recently, swimming-style colour synaesthesia was introduced as a new form of synaesthesia. A synaesthetic Stroop test was used to establish its genuineness. Since Stroop interference can occur for any type of overlearned association, in the present study we used a modified Stroop test and psychophysiological synaesthetic conditioning to further establish the genuineness of this form of synaesthesia. We compared the performance of a swimming-style colour synaesthete and a control who was trained on swimming-style colour associations. Our results showed that behavioural aspects of swimming-style colour synaesthesia can be mimicked in a trained control. Importantly, however, our results showed a psychophysiological conditioning effect for the synaesthete only. We discuss the theoretical relevance of swimming-style colour synaesthesia according to different models of synaesthesia. We conclude that swimming-style colour synaesthesia is a genuine form of synaesthesia, can be mimicked behaviourally in non-synaesthetes, and is best explained by a re-entrant feedback model. Copyright © 2012 Elsevier Inc. All rights reserved.
Effect of swim exercise training on human muscle fiber function
NASA Technical Reports Server (NTRS)
Fitts, R. H.; Costill, D. L.; Gardetto, P. R.
1989-01-01
The effect of swim exercise training on the human muscle fiber function was investigated in swimmers trained in a typical collegiate swim-training program followed by an intensified 10-day training period. The measured parameters included the peak tension (P0), negative log molar Ca(2+) concentration (pCa)-force, and maximal shortening speed (Vmax) of the slow-twitch type I and fast-twitch type II fibers obtained by biopsy from the deltoid muscle. The P0 values were found to be not altered after either the training or the 10-day intensive program. The type I fibers from the trained swimmers showed pCa-force curves shifted to the right, such that higher free Ca(2+) levels were required to elicit a given percent of P0. The training program significantly increased the Vmax in the type I fibers and decreased that of the type II fibers, and the 10-day intensive training produced a further significant decrease of the type II fibers.
Sports injuries during the Summer Olympic Games 2008.
Junge, Astrid; Engebretsen, Lars; Mountjoy, Margo L; Alonso, Juan Manuel; Renström, Per A F H; Aubry, Mark John; Dvorak, Jiri
2009-11-01
Standardized assessment of sports injuries provides important epidemiological information and also directions for injury prevention. To analyze the frequency, characteristics, and causes of injuries incurred during the Summer Olympic Games 2008. Descriptive epidemiology study. The chief physicians and/or chief medical officers of the national teams were asked to report daily all injuries newly incurred during the Olympic Games on a standardized injury report form. In addition, injuries were reported daily by the physicians at the medical stations at the different Olympic venues and at the polyclinic in the Olympic Village. Physicians and/or therapists of 92 national teams covering 88% of the 10,977 registered athletes took part in the study. In total, 1055 injuries were reported, resulting in an incidence of 96.1 injuries per 1000 registered athletes. Half of the injuries (49.6%) were expected to prevent the athlete from participating in competition or training. The most prevalent diagnoses were ankle sprains and thigh strains. The majority (72.5%) of injuries were incurred in competition. One third of the injuries were caused by contact with another athlete, followed by overuse (22%) and noncontact incidences (20%). Injuries were reported from all sports, but their incidence and characteristics varied substantially. In relation to the number of registered athletes, the risk of incurring an injury was highest in soccer, taekwondo, hockey, handball, weightlifting, and boxing (all >or=15% of the athletes) and lowest for sailing, canoeing/kayaking, rowing, synchronized swimming, diving, fencing, and swimming. The data indicate that the injury surveillance system covered almost all of the participating athletes, and the results highlight areas of high risk for sport injury such as the in-competition period, the ankle and thigh, and specific sports. The identification of these factors should stimulate future research and subsequent policy change to prevent injury in elite athletes.
Is Swimming Safe in Heart Failure? A Systematic Review.
Shah, Parin; Pellicori, Pierpaolo; Macnamara, Alexandra; Urbinati, Alessia; Clark, Andrew L
It is not clear whether swimming is safe in patients with chronic heart failure. Ten studies examining the hemodynamic effects of acute water immersion (WI) (155 patients; average age 60 years; 86% male; mean left ventricular ejection fraction (LVEF) 29%) and 6 randomized controlled trials of rehabilitation comparing swimming with either medical treatment only (n = 3) or cycling (n = 1) or aerobic exercise (n = 2), (136 patients, average age 59 years; 84% male, mean LVEF 31%) were considered. In 7 studies of warm WI (30-35°C): heart rate (HR) fell (2% to -15%), and both cardiac output (CO) (7-37%) and stroke volume (SV) increased (13-41%). In 1 study of hot WI (41°C), systemic vascular resistance (SVR) fell (41%) and HR increased (33%). In 2 studies of cold WI (12-22°C), there were no consistent effects on HR and CO. Compared with medical management, swimming led to a greater increase in peak VO2 (7-14%) and 6 minute walk test (6MWT) (7-13%). Compared with cycle training, combined swimming and cycle training led to a greater reduction in resting HR (16%), a greater increase in resting SV (23%) and SVR (15%), but no changes in resting CO and a lesser increase in peak VO2 (6%). Compared with aerobic training, combined swimming and aerobic training lead to a reduction in resting HR (19%) and SVR (54%) and a greater increase in SV (34%), resting CO (28%), LVEF (9%), and 6MWT (70%). Although swimming appears to be safe, the studies conducted have been small, very heterogeneous, and inconclusive.
Mooney, Robert; Corley, Gavin; Godfrey, Alan; Osborough, Conor; ÓLaighin, Gearóid
2017-01-01
Aims The study aims were to evaluate the validity of two commercially available swimming activity monitors for quantifying temporal and kinematic swimming variables. Methods Ten national level swimmers (5 male, 5 female; 15.3±1.3years; 164.8±12.9cm; 62.4±11.1kg; 425±66 FINA points) completed a set protocol comprising 1,500m of swimming involving all four competitive swimming strokes. Swimmers wore the Finis Swimsense and the Garmin Swim activity monitors throughout. The devices automatically identified stroke type, swim distance, lap time, stroke count, stroke rate, stroke length and average speed. Video recordings were also obtained and used as a criterion measure to evaluate performance. Results A significant positive correlation was found between the monitors and video for the identification of each of the four swim strokes (Garmin: X2 (3) = 31.292, p<0.05; Finis:X2 (3) = 33.004, p<0.05). No significant differences were found for swim distance measurements. Swimming laps performed in the middle of a swimming interval showed no significant difference from the criterion (Garmin: bias -0.065, 95% confidence intervals -3.828–6.920; Finis bias -0.02, 95% confidence intervals -3.095–3.142). However laps performed at the beginning and end of an interval were not as accurately timed. Additionally, a statistical difference was found for stroke count measurements in all but two occasions (p<0.05). These differences affect the accuracy of stroke rate, stroke length and average speed scores reported by the monitors, as all of these are derived from lap times and stroke counts. Conclusions Both monitors were found to operate with a relatively similar performance level and appear suited for recreational use. However, issues with feature detection accuracy may be related to individual variances in stroke technique. It is reasonable to expect that this level of error would increase when the devices are used by recreational swimmers rather than elite swimmers. Further development to improve accuracy of feature detection algorithms, specifically for lap time and stroke count, would also increase their suitability within competitive settings. PMID:28178301
Mooney, Robert; Quinlan, Leo R; Corley, Gavin; Godfrey, Alan; Osborough, Conor; ÓLaighin, Gearóid
2017-01-01
The study aims were to evaluate the validity of two commercially available swimming activity monitors for quantifying temporal and kinematic swimming variables. Ten national level swimmers (5 male, 5 female; 15.3±1.3years; 164.8±12.9cm; 62.4±11.1kg; 425±66 FINA points) completed a set protocol comprising 1,500m of swimming involving all four competitive swimming strokes. Swimmers wore the Finis Swimsense and the Garmin Swim activity monitors throughout. The devices automatically identified stroke type, swim distance, lap time, stroke count, stroke rate, stroke length and average speed. Video recordings were also obtained and used as a criterion measure to evaluate performance. A significant positive correlation was found between the monitors and video for the identification of each of the four swim strokes (Garmin: X2 (3) = 31.292, p<0.05; Finis:X2 (3) = 33.004, p<0.05). No significant differences were found for swim distance measurements. Swimming laps performed in the middle of a swimming interval showed no significant difference from the criterion (Garmin: bias -0.065, 95% confidence intervals -3.828-6.920; Finis bias -0.02, 95% confidence intervals -3.095-3.142). However laps performed at the beginning and end of an interval were not as accurately timed. Additionally, a statistical difference was found for stroke count measurements in all but two occasions (p<0.05). These differences affect the accuracy of stroke rate, stroke length and average speed scores reported by the monitors, as all of these are derived from lap times and stroke counts. Both monitors were found to operate with a relatively similar performance level and appear suited for recreational use. However, issues with feature detection accuracy may be related to individual variances in stroke technique. It is reasonable to expect that this level of error would increase when the devices are used by recreational swimmers rather than elite swimmers. Further development to improve accuracy of feature detection algorithms, specifically for lap time and stroke count, would also increase their suitability within competitive settings.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-04-08
...-AA08 Special Local Regulations; Marine Events, Potomac River; National Harbor Access Channel, MD AGENCY... special local regulations during the ``Swim Across the Potomac'' swimming competition, to be held on the waters of the Potomac River on June 2, 2013. These special local regulations are necessary to provide for...
Yuan, Wen-Xue; Liu, Hai-Bin; Gao, Feng-Shan; Wang, Yan-Xia; Qin, Kai-Rong
2016-12-28
Exercise has been found to either reduce or increase arterial stiffness. Land-based exercise modalities have been documented as effective physical therapies to decrease arterial stiffness. However, these land-based exercise modalities may not be suitable for overweight individuals, in terms of risks of joint injury. The purpose of this study was to determine the effects of 8-week swimming training and 4-week detraining on carotid arterial stiffness and hemodynamics in young overweight adults. Twenty young male adults who were overweight were recruited and engaged in 8-week of swimming training and 4-week detraining. Five individuals withdrew due to lack of interest and failure to follow the training protocol. Body Fat Percentage (BFP) and carotid hemodynamic variables were measured on a resting day at the following intervals: baseline, 4 weeks, 8 weeks after swimming training and 4 weeks after detraining. A repeated analysis of variance (ANOVA) was used to assess the differences between baseline and each measurement. When significant differences were detected, Tukey's test for post hoc comparisons was used. Eight-week swimming training at moderate intensity decreased BFP, including the trunk and four extremities. Additionally, the BFP of the right and left lower extremities continued to decrease in these overweight adults 4 weeks after ceasing training. Carotid arterial stiffness decreased, while there were no significant changes in arterial diameters. Blood flow velocity, flow rate, maximal and mean wall shear stress increased, while systolic blood pressure and peripheral resistance decreased. No significant differences existed in minimal wall shear stress and oscillatory shear stress. Eight-week swimming training at moderate intensity exhibited beneficial effects on systolic blood pressure, arterial stiffness and blood supply to the brain in overweight adults. Moreover, maximal and mean wall shear stress increased after training. It is worth noting that these changes in hemodynamics did not last 4 weeks. Therefore, further studies are still warranted to clarify the underlying relationship between improvements in arterial stiffness and alterations in wall shear stress.
Identifying swimmers as water-polo or swim team-mates from visual displays of less than one second.
Steel, Kylie A; Adams, Roger D; Canning, Colleen G
2007-09-01
Opportunities for ball passing in water-polo may be brief and the decision to pass only informed by minimal visual input. Since researchers using point light displays have shown that the walking or running gait of familiars can be identified, water-polo players may have the ability to recognize team-mates from their swimming gait. To test this hypothesis, members of a water-polo team and a competition swim team viewed two randomized sets of video clips, each less than one second long, of swimmers from both teams sprinting freestyle past a fixed camera. The arm stroke clip sequence showed only the upper body, and the kick sequence showed only the lower body. After viewing each video clip, observers rated their level of certainty as to whether the swimmer presented was a team-mate or not. Discrimination was significantly above chance in both groups. Water-polo players were better able to identify team-mates from their kick, whereas swimmers were better able to do so by viewing arm stroke. Our results suggest that, as with walking and running gait, small amounts of visual information about swimmers can be used for recognition, and so raise the possibility that specific training may be able to improve team-mate classification in water-polo, particularly in newly formed teams.
Substrate Metabolism During Ironman Triathlon: Different Horses on the Same Courses.
Maunder, Ed; Kilding, Andrew E; Plews, Daniel J
2018-05-18
Ironman triathlons are ultra-endurance events of extreme duration. The performance level of those competing varies dramatically, with elite competitors finishing in ~ 8:00:00, and lower performing amateurs finishing in ~ 14-15:00:00. When applying appropriate values for swimming, cycling and running economies to these performance times, it is demonstrated that the absolute energy cost of these events is high, and the rate of energy expenditure increases in proportion with the athlete's competitive level. Given the finite human capacity for endogenous carbohydrate storage, minimising the endogenous carbohydrate cost associated with performing exercise at competitive intensities should be a goal of Ironman preparation. A range of strategies exist that may help to achieve this goal, including, but not limited to, adoption of a low-carbohydrate diet, exogenous carbohydrate supplementation and periodised training with low carbohydrate availability. Given the diverse metabolic stimuli evoked by Ironman triathlons at different performance levels, it is proposed that the performance level of the Ironman triathlete is considered when adopting metabolic strategies to minimise the endogenous carbohydrate cost associated with exercise at competitive intensities. Specifically, periodised training with low carbohydrate availability combined with exogenous carbohydrate supplementation during competition might be most appropriate for elite and top-amateur Ironman triathletes who elicit very high rates of energy expenditure. Conversely, the adoption of a low-carbohydrate or ketogenic diet might be appropriate for some lower performance amateurs (> 12 h), in whom associated high rates of fat oxidation may be almost completely sufficient to match the energy demands required.
Dawson, Brian; Vladich, Todd; Blanksby, Brian A
2002-11-01
To determine whether 4 weeks of oral creatine (Cr) supplementation could enhance single freestyle sprint and swim bench performance in experienced competitive junior swimmers, 10 young men and 10 young women (x age = 16.4 +/- 1.8 years) participated in a 27-day supplementation period and pre- and posttesting sessions. In session 1 (presupplementation testing), subjects swam one 50-m freestyle and then (after approximately 5 minutes of active recovery) one 100-m freestyle at maximum speed. Blood lactate was measured before and 1 minute after each swim trial. Forty-eight hours later, height, mass, and the sum of 6 skinfolds were recorded, and a Biokinetic Swim Bench total work output test (2 x 30-second trials, with a 10-minute passive recovery in between) was undertaken. After the pretests were completed, participants were divided into 2 groups (n = 10, Cr; and n = 10, placebo) by means of matched pairs on the basis of gender and 50-m swim times. A Cr loading phase of 20 g x d(-1) for 5 days was then instituted, followed by a maintenance phase of 5 g x d(-1) for 22 days. Postsupplementation testing replicated the presupplementation tests. Four weeks of Cr supplementation did not influence single sprint performance in the pool or body mass and composition. However, 30-second swim bench total work scores for trial 1 and trial 2 increased after Cr (p < 0.05) but not placebo ingestion. Postexercise blood lactate values were not different after supplementation for the 50- and 100-m sprint trials either within or between groups. It was concluded that 4 weeks of Cr supplementation did not significantly improve single sprint performance in competitive junior swimmers, but it did enhance swim bench test performance.
Kılıç, M; Ulusoy, Ö; Cırrık, S; Hindistan, I E; Ozkaya, Y Gül
2014-03-01
The purpose of this study was to investigate the possible role of moderate and strenuous swimming training on plasma and cerebrospinal fluid (CSF) IL-6 (interleukin-6) levels during recovery from exhaustive exercise in rats. Wistar rats were divided into three groups: sedentary control (C), moderately trained (MT) and strenuously trained (ST). MT rats underwent swimming exercise for one hour/day and 5 days/week for 8 weeks. Animals in the ST group began swimming with 1 h/day and swimming duration was progressively increased by 30 min/wk, reaching 2.5 h/day by week 4 and stayed constant for an additional 4 weeks. After all animals underwent an acute exhaustive swimming exercise, animals were divided into 3 groups, and decapitated immediately, 24 and 48 hours after exhaustion to obtain tissue samples. Muscle citrate synthase activity, plasma and CSF IL-6 levels were determined. The citrate synthase activity was found to be higher in MT and ST groups compared to the C group. Although plasma IL-6 levels were found unaltered among all groups, the CSF IL-6 concentration was found to be increased 24 hours after exhaustive exercise of the ST group. We conclude that exercise training intensity is an important factor determining cerebrospinal IL-6 concentration after exhaustive exercise.
Giving Ourselves Ourselves: A Story about Success
ERIC Educational Resources Information Center
McKinlay, Neil W.
2006-01-01
In this article, the author uses a personal story to challenge the definition of success--introducing Ann, who comes in last in a swimming competition, but wins after all. He has drawn on his years as a swim coach to generate a series of stories exploring the emotional side of learning and the role of compassion in teaching that too often lie…
A Comparative Analysis of Swimming Styles in Competitive Swimming
NASA Astrophysics Data System (ADS)
von Loebbecke, Alfred; Mittal, Rajat; Gupta, Varun; Mark, Russell
2007-11-01
High-fidelity numerical simulations are being used to conduct a critical evaluation of swimming strokes in competitive swimming. We combine computational fluid dynamics (CFD), laser body scans, animation software, and video footage to develop accurate models of Olympic level swimmers and use these to examine contrasting styles of the dolphin kick as well as the arm strokes in back and front crawl stroke. In the dolphin kick, the focus is on examining the effects of Strouhal number, kick amplitude, frequency, and technique on thrust production. In the back stroke, we examine the performance of the so called ``flat stroke'' versus the ``deep catch,'' The most important aspect that separates the two major types of back stroke is the alignment or angle of attack of the palm during the stroke. In one style of front crawl arm stroke, there is greater elbow joint flexion, shoulder abduction and sculling whereas the other style consists of a straight arm pull dominated by simple shoulder flexion. Underlying the use of these two styles is the larger and more fundamental issue of the role of lift versus drag in thrust production and we use the current simulations to examine this issue in detail.
Analysis of swimming performance: perceptions and practices of US-based swimming coaches.
Mooney, Robert; Corley, Gavin; Godfrey, Alan; Osborough, Conor; Newell, John; Quinlan, Leo Richard; ÓLaighin, Gearóid
2016-01-01
In elite swimming, a broad range of methods are used to assess performance, inform coaching practices and monitor athletic progression. The aim of this paper was to examine the performance analysis practices of swimming coaches and to explore the reasons behind the decisions that coaches take when analysing performance. Survey data were analysed from 298 Level 3 competitive swimming coaches (245 male, 53 female) based in the United States. Results were compiled to provide a generalised picture of practices and perceptions and to examine key emerging themes. It was found that a disparity exists between the importance swim coaches place on biomechanical analysis of swimming performance and the types of analyses that are actually conducted. Video-based methods are most frequently employed, with over 70% of coaches using these methods at least monthly, with analyses being mainly qualitative in nature rather than quantitative. Barriers to the more widespread use of quantitative biomechanical analysis in elite swimming environments were explored. Constraints include time, cost and availability of resources, but other factors such as sources of information on swimming performance and analysis and control over service provision are also discussed, with particular emphasis on video-based methods and emerging sensor-based technologies.
Computational Modeling of the Dolphin Kick in Competitive Swimming
NASA Astrophysics Data System (ADS)
Loebbeck, A.; Mark, R.; Bhanot, G.
2005-11-01
Numerical simulations are being used to study the fluid dynamics of the dolphin kick in competitive swimming. This stroke is performed underwater after starts and turns and involves an undulatory motion of the body. Highly detailed laser body scans of elite swimmers are used and the kinematics of the dolphin kick is recreated from videos of Olympic level swimmers. We employ a parallelized immersed boundary method to simulate the flow associated with this stroke in all its complexity. The simulations provide a first of its kind glimpse of the fluid and vortex dynamics associated with this stroke and hydrodynamic force computations allow us to gain a better understanding of the thrust producing mechanisms.
Tahir, Enver; Starekova, Jitka; Muellerleile, Kai; von Stritzky, Alexandra; Münch, Julia; Avanesov, Maxim; Weinrich, Julius M; Stehning, Christian; Bohnen, Sebastian; Radunski, Ulf K; Freiwald, Eric; Blankenberg, Stefan; Adam, Gerhard; Pressler, Axel; Patten, Monica; Lund, Gunnar K
2017-12-08
This study analyzed the presence of myocardial fibrosis detected by late gadolinium-enhancement (LGE) cardiac magnetic resonance (CMR) in correlation with the performance of competitive triathletes objectified by an exercise test and individual competition history. Myocardial fibrosis detected by LGE CMR has been reported to occur in 0% to 50% of asymptomatic athletes. However, the cause and mechanisms of myocardial fibrosis are unclear. Eighty-three asymptomatic triathletes undergoing >10 training h per week (43 ± 10 years of age; 65% male) and 36 sedentary controls were studied by using LGE and extracellular volume (ECV) CMR. Parameters of physical fitness were measured by spiroergometry. Triathletes reported their lifetime competition results. LGE CMR revealed focal nonischemic myocardial fibrosis in 9 of 54 (17%) male triathletes (LGE + ) but in none of the female triathletes (p < 0.05). LGE + triathletes had higher peak exercise systolic blood pressure (213 ± 24 mm Hg) than LGE - triathletes (194 ± 26 mm Hg; p < 0.05). Furthermore, left ventricular mass index was higher in LGE + triathletes (93 ± 7 g/m 2 ) than in LGE - triathletes (84 ± 11 g/m 2 ; p < 0.05). ECV in LGE - myocardium was higher in LGE + triathletes (26.3 ± 1.8%) than in LGE - triathletes (24.4 ± 2.2%; p < 0.05). LGE + triathletes completed longer cumulative distances in swimming and cycling races and participated more often in middle and Iron Man distances than LGE - triathletes. A cycling race distance of >1,880 km completed during competition had the highest accuracy to predict LGE, with an area under the curve value of 0.876 (p < 0.0001), resulting in high sensitivity (89%) and specificity (79%). Multivariate analysis identified peak exercise systolic blood pressure (p < 0.05) and the swimming race distance (p < 0.01) as independent predictors of LGE presence. Myocardial fibrosis in asymptomatic triathletes seems to be associated with exercise-induced hypertension and the race distances. There appears to be a safe upper limit, beyond which exercise may result in myocardial fibrosis. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.
Analysis of Drafting Effects in Swimming Using Computational Fluid Dynamics
Silva, António José; Rouboa, Abel; Moreira, António; Reis, Victor Machado; Alves, Francisco; Vilas-Boas, João Paulo; Marinho, Daniel Almeida
2008-01-01
The purpose of this study was to determine the effect of drafting distance on the drag coefficient in swimming. A k-epsilon turbulent model was implemented in the commercial code Fluent® and applied to the fluid flow around two swimmers in a drafting situation. Numerical simulations were conducted for various distances between swimmers (0.5-8.0 m) and swimming velocities (1.6-2.0 m.s-1). Drag coefficient (Cd) was computed for each one of the distances and velocities. We found that the drag coefficient of the leading swimmer decreased as the flow velocity increased. The relative drag coefficient of the back swimmer was lower (about 56% of the leading swimmer) for the smallest inter-swimmer distance (0.5 m). This value increased progressively until the distance between swimmers reached 6.0 m, where the relative drag coefficient of the back swimmer was about 84% of the leading swimmer. The results indicated that the Cd of the back swimmer was equal to that of the leading swimmer at distances ranging from 6.45 to 8. 90 m. We conclude that these distances allow the swimmers to be in the same hydrodynamic conditions during training and competitions. Key pointsThe drag coefficient of the leading swimmer decreased as the flow velocity increased.The relative drag coefficient of the back swimmer was least (about 56% of the leading swimmer) for the smallest inter-swimmer distance (0.5 m).The drag coefficient values of both swimmers in drafting were equal to distances ranging between 6.45 m and 8.90 m, considering the different flow velocities.The numerical simulation techniques could be a good approach to enable the analysis of the fluid forces around objects in water, as it happens in swimming. PMID:24150135
Female promiscuity promotes the evolution of faster sperm in cichlid fishes
Fitzpatrick, John L.; Montgomerie, Robert; Desjardins, Julie K.; Stiver, Kelly A.; Kolm, Niclas; Balshine, Sigal
2009-01-01
Sperm competition, the contest among ejaculates from rival males to fertilize ova of a female, is a common and powerful evolutionary force influencing ejaculate traits. During competitive interactions between ejaculates, longer and faster spermatozoa are expected to have an edge; however, to date, there has been mixed support for this key prediction from sperm competition theory. Here, we use the spectacular radiation of cichlid fishes from Lake Tanganyika to examine sperm characteristics in 29 closely related species. We provide phylogenetically robust evidence that species experiencing greater levels of sperm competition have faster-swimming sperm. We also show that sperm competition selects for increases in the number, size, and longevity of spermatozoa in the ejaculate of a male, and, contrary to expectations from theory, we find no evidence of trade-offs among sperm traits in an interspecific analysis. Also, sperm swimming speed is positively correlated with sperm length among, but not within, species. These different responses to sperm competition at intra- and interspecific levels provide a simple, powerful explanation for equivocal results from previous studies. Using phylogenetic analyses, we also reconstructed the probable evolutionary route of trait evolution in this taxon, and show that, in response to increases in the magnitude of sperm competition, the evolution of sperm traits in this clade began with the evolution of faster (thus, more competitive) sperm. PMID:19164576
ERIC Educational Resources Information Center
Casey, Amanda Faith; Emes, Claudia
2011-01-01
Reduced respiratory muscle strength in individuals with Down syndrome (DS) may affect speech respiratory variables such as maximum phonation duration (MPD), initiation volume, and expired mean airflow. Researchers randomly assigned adolescents with DS (N = 28) to either 12 weeks of swim training (DS-ST) or a control group (DS-NT). Repeated…
Peng, Chiung-Chi; Chen, Kuan-Chou; Hsieh, Chiu-Lan; Peng, Robert Y.
2012-01-01
Background The renal function of chronic kidney disease (CKD) patients may be improved by a number of rehabilitative mechanisms. Swimming exercise training was supposed to be beneficial to its recovery. Methodology/Principal Findings Doxorubicin-induced CKD (DRCKD) rat model was performed. Swimming training was programmed three days per week, 30 or 60 min per day for a total period of 11 weeks. Serum biochemical and pathological parameters were examined. In DRCKD, hyperlipidemia was observed. Active mesangial cell activation was evidenced by overexpression of PDGFR, P-PDGFR, MMP-2, MMP-9, α-SMA, and CD34 with a huge amount collagen deposition. Apparent myofibroblast transdifferentiation implicating fibrogenesis in the glomerular mesangium, glomerulonephritis and glomeruloscelorosis was observed with highly elevated proteinuria and urinary BUN excretion. The 60-min swimming exercise but not the 30 min equivalent rescued most of the symptoms. To quantify the effectiveness of exercise training, a physical parameter, i.e. “the strenuosity coefficient” or “the myokine releasing coefficient”, was estimated to be 7.154×10−3 pg/mL-J. Conclusions The 60-min swimming exercise may ameliorate DRCKD by inhibiting the transdifferentiation of myofibroblasts in the glomerular mesangium. Moreover, rehabilitative exercise training to rescue CKD is a personalized remedy. Benefits depend on the duration and strength of exercise, and more importantly, on the individual physiological condition. PMID:22761655
May, Zacnicte; Fouad, Karim; Shum-Siu, Alice; Magnuson, David S K
2015-09-15
A rarely explored subject in animal research is the effect of pre-injury variables on behavioral outcome post-SCI. Low reporting of such variables may underlie some discrepancies in findings between laboratories. Particularly, intensive task-specific training before a SCI might be important, considering that sports injuries are one of the leading causes of SCI. Thus, individuals with SCI often underwent rigorous training before their injuries. In the present study, we asked whether training before SCI on a grasping task or a swimming task would influence motor recovery in rats. Swim pre-training impaired recovery of swimming 2 and 4 weeks post-injury. This result fits with the idea of motor learning interference, which posits that learning something new may disrupt learning of a new task; in this case, learning strategies to compensate for functional loss after SCI. In contrast to swimming, grasp pre-training did not influence grasping ability after SCI at any time point. However, grasp pre-trained rats attempted to grasp more times than untrained rats in the first 4 weeks post-injury. Also, lesion volume of grasp pre-trained rats was greater than that of untrained rats, a finding which may be related to stress or activity. The increased participation in rehabilitative training of the pre-trained rats in the early weeks post-injury may have potentiated spontaneous plasticity in the spinal cord and counteracted the deleterious effect of interference and bigger lesions. Thus, our findings suggest that pre-training plays a significant role in recovery after CNS damage and needs to be carefully controlled for. Copyright © 2015 Elsevier B.V. All rights reserved.
Effects of high-intensity swimming training on the bones of ovariectomized rats
Oh, Taewoong; Tanaka, Sakura; Naka, Tatsuki; Igawa, Shoji
2016-01-01
[Purpose] This study was performed to assess the effects of high-intensity intermittent swimming training(HIT) on bone in ovariectomized rats. [Methods] Six-week-old female Sprague-Dawley rats were randomly assigned to either sham operation or bilateral ovariectomy. After surgery, they were divided into the following four groups: 1) sham-operated sedentary (S), 2) sham-operated exercise training (SE), 3) OVX sedentary (O), 4) OVX exercise training (OE) 5) OVX given 17β-estradiol (OE2) and 6) OVX exercise training and given 17β-estradiol (OEE). SE, OE and OEE rats were used extremely high-intensity swim exercise. The rats repeated fourteen 20-s swimming bouts with a weight equivalent to 14, 15, and 16% of body weight for the first 5, the next 9, and the last 5 days, respectively. Between exercise bouts, a 10-s pause was allowed. HIT was originally designed as an exercise method; a method that very quickly induces an increase in the maximum oxygen intake (Tabata I et al., 1996). OEE and OE2 rats were subcutaneously injected ethanol with 25μg/kg body weight 17β-estradiol 3 times per week. [Results] Bone strength, bone mineral density and trabecular bone parameters were measured after a 8-weeks experimental period. Bone strength was significantly higher in the SE, OE, OE2 and OEE group compared with the O group. BV/TV was significant increase in the SE, OE groups compared with the O group. BMD showed no difference in the OE group compared with the O group. [Conclusion] This study demonstrate some beneficial effects of postmenopausal osteoporosis of high-intensity intermittent swimming training on bone structure and strength. PMID:27757386
Effects of high-intensity swimming training on the bones of ovariectomized rats.
Oh, Taewoong; Tanaka, Sakura; Naka, Tatsuki; Igawa, Shoji
2016-09-01
This study was performed to assess the effects of high-intensity intermittent swimming training(HIT) on bone in ovariectomized rats. Six-week-old female Sprague-Dawley rats were randomly assigned to either sham operation or bilateral ovariectomy. After surgery, they were divided into the following four groups: 1) sham-operated sedentary (S), 2) sham-operated exercise training (SE), 3) OVX sedentary (O), 4) OVX exercise training (OE) 5) OVX given 17β-estradiol (OE2) and 6) OVX exercise training and given 17β-estradiol (OEE). SE, OE and OEE rats were used extremely high-intensity swim exercise. The rats repeated fourteen 20-s swimming bouts with a weight equivalent to 14, 15, and 16% of body weight for the first 5, the next 9, and the last 5 days, respectively. Between exercise bouts, a 10-s pause was allowed. HIT was originally designed as an exercise method; a method that very quickly induces an increase in the maximum oxygen intake (Tabata I et al., 1996). OEE and OE2 rats were subcutaneously injected ethanol with 25μg/kg body weight 17β-estradiol 3 times per week. Bone strength, bone mineral density and trabecular bone parameters were measured after a 8-weeks experimental period. Bone strength was significantly higher in the SE, OE, OE2 and OEE group compared with the O group. BV/TV was significant increase in the SE, OE groups compared with the O group. BMD showed no difference in the OE group compared with the O group. This study demonstrate some beneficial effects of postmenopausal osteoporosis of high-intensity intermittent swimming training on bone structure and strength.
Effects of soccer vs swim training on bone formation in sedentary middle-aged women.
Mohr, Magni; Helge, Eva W; Petersen, Liljan F; Lindenskov, Annika; Weihe, Pál; Mortensen, Jann; Jørgensen, Niklas R; Krustrup, Peter
2015-12-01
The present study examined the effects of 15 weeks of soccer training and two different swimming training protocols on bone turnover in sedentary middle-aged women. Eighty-three premenopausal mildly hypertensive women [age: 45 ± 6 (± SD) years, height: 165 ± 6 cm, weight: 80.0 ± 14.1 kg, body fat: 42.6 ± 5.7 %, systolic blood pressure/diastolic blood pressure: 138 ± 6/85 ± 3 mmHg] were randomized into soccer training (SOC, n = 21), high-intensity intermittent swimming (HS, n = 21), moderate-intensity swimming (MS, n = 21) intervention groups, and a control group (C, n = 20). The training groups completed three sessions per week for 15 weeks. DXA scans were performed and resting blood samples were drawn pre- and post-intervention. In SOC, plasma osteocalcin, procollagen type I N propeptide and C-terminal telopeptide increased (P < 0.05) by 37 ± 15, 52 ± 23 and 42 ± 18 %, respectively, with no changes in MS, HS and C. The intervention-induced increase in SOC was larger (P < 0.05) than in MS, HS and C. In SOC, leg BMC increased (P < 0.05) by 3.1 ± 4.5 %, with a larger increase in SOC than in C. Femoral shaft and trochanter bone mineral density (BMD) increased (P < 0.05) by 1.7 ± 1.9 and 2.4 ± 2.9 %, respectively, in SOC, with a greater (P < 0.05) change in SOC than in MS and C, whereas total body and total leg BMD did not change in any of the groups. In conclusion, 15 weeks of soccer training with sedentary middle-aged women caused marked increases in bone turnover markers, with concomitant increases in leg bone mass. No changes in bone formation and resorption markers were seen after prolonged submaximal or high-intensity intermittent swimming training. Thus, soccer training appears to provide a powerful osteogenic stimulus in middle-aged women.
Li, Xiuming; Zhang, Yaoguang; Li, Xiaojin; Zheng, Hua; Peng, Jianglan
2018-01-01
ABSTRACT The objectives of this study were to examine whether sustained exercise training at four water velocities, i.e. nearly still water (control), 1 body length (BL) s−1, 2 BL s−1 and 4 BL s−1, has effects on swimming performance and digestive metabolism in juvenile black carp (Mylopharyngodon piceus). The results demonstrated that fish subjected to sustained training at 2 and 4 BL s−1 showed significantly higher critical swimming speed (Ucrit) and maximum metabolic rate (MMR) over the control group. Fish subjected to sustained training at 1 and 2 BL s−1 showed a significantly (30 and 54%) prolonged duration, 14 and 17% higher postprandial ṀO2 increment (i.e. ṀO2peak), and 62 and 92% more energy expended on specific dynamic action (SDA), respectively, after consuming a similar meal over fish kept in nearly still water. These results suggest that (1) sustained exercise training at a higher speed (2 or 4 BL s−1) had a positive influence on the aerobic swimming performance of juvenile M. piceus, which may be associated with improved aerobic metabolism; and (2) sustained exercise training at a lower speed (1 or 2 BL s−1) resulted in elevated postprandial metabolic responses in juvenile M. piceus. PMID:29463516
Leite, Nayara de Carvalho; Ferreira, Thiago Rentz; Rickli, Sarah; Borck, Patricia Cristine; Mathias, Paulo Cezar de Freitas; Emilio, Henriette Rosa de Oliveira; Grassiolli, Sabrina
2013-01-01
Obese rats obtained by neonatal monosodium glutamate (MSG) administration present insulin hypersecretion. The metabolic mechanism by which glucose catabolism is coupled to insulin secretion in the pancreatic β-cells from MSG-treated rats is understood. The purpose of this study was to evaluate glucose metabolism in pancreatic islets from MSG-treated rats subjected to swimming training. MSG-treated and control (CON) rats swam for 30 minutes (3 times/week) over a period of 10 weeks. Pancreatic islets were isolated and incubated with glucose in the presence of glycolytic or mitochondrial inhibitors. Swimming training attenuated fat pad accumulation, avoiding changes in the plasma levels of lipids, glucose and insulin in MSG-treated rats. Adipocyte and islet hypertrophy observed in MSG-treated rats were attenuated by exercise. Pancreatic islets from MSG-treated obese rats also showed insulin hypersecretion, greater glucose transporter 2 (GLUT2) expression, increased glycolytic flux and reduced mitochondrial complex III activity. Swimming training attenuated islet hypertrophy and normalised GLUT2 expression, contributing to a reduction in the glucose responsiveness of pancreatic islets from MSG-treated rats without altering glycolytic flux. However, physical training increased the activity of mitochondrial complex III in pancreatic islets from MSG-treated rats without a subsequent increase in glucose-induced insulin secretion. Copyright © 2013 S. Karger AG, Basel.
Morouço, Pedro G; Marinho, Daniel A; Keskinen, Kari L; Badillo, Juan J; Marques, Mário C
2014-11-01
The purpose of this study was two-fold: (a) to compare stroke and the physiological responses between maximal tethered and free front crawl swimming and (b) to evaluate the contribution of force exertion for swimming performance over short distances. A total of 34 male swimmers, representing various levels of competitive performance, participated in this study. Each participant was tested in both a 30-second maximal tethered swimming test and a 50-m free swimming test. The tethered force parameters, the swimming speed, stroke (stroke rate [SR]), and the physiological responses (increase in blood lactate concentration [ΔBLa], heart rate, and rate of perceived exertion) were recorded and calculated. The results showed no differences in stroke and the physiological responses between tethered and free swimming, with a high level of agreement for the SR and ΔBLa. A strong correlation was obtained between the maximum impulse of force per stroke and the speed (r = 0.91; p < 0.001). Multiple regression analysis revealed that the maximum impulse and SR in the tethered condition explained 84% of the free swimming performance. The relationship between the swimming speed and maximum force tended to be nonlinear, whereas linear relationships were observed with the maximum impulse. This study demonstrates that tethered swimming does not significantly alter stroke and the physiological responses compared with free swimming, and that the maximum impulse per stroke should be used to evaluate the balance between force and the ability to effectively apply force during sprint swimming. Consequently, coaches can rely on tethered forces to identify strength deficits and improve swimming performance over short distances.
Feijen, Stef; Kuppens, Kevin; Tate, Angela; Baert, Isabel; Struyf, Thomas; Struyf, Filip
2018-04-17
Measuring thoracic spine mobility can be of interest to competitive swimmers as it has been associated with shoulder girdle function and scapular position in subjects with and without shoulder pain. At present, no reliability data of thoracic spine mobility measurements are available in the swimming population. This study aims to evaluate the within-session intra- and interrater reliability of the "lumbar-locked rotation test" for thoracic spine rotation in competitive swimmers aged 10 to 18 years. This reliability study is part of a larger prospective cohort study investigating potential risk factors for the development of shoulder pain in competitive swimmers. Within-session, intra- and inter-rater reliability. Competitive swimming clubs in Belgium. 21 competitive swimmers. Intra- and inter-rater reliability of the lumbar-locked thoracic rotation test. Intraclass correlation coefficients (ICCs) ranged from 0.91 (95% CI 0.78 to 0.96) to 0.96 (0.89-0.98) for intra-rater reliability. Results for inter-rater reliability ranged from 0.89 (0.72-0.95) to 0.86 (0.65-0.94) respectively for right and left thoracic rotation. Results suggest good to excellent reliability of the lumbar-locked thoracic rotation test, indicating this test can be used reliably in clinical practice. Copyright © 2018 Elsevier Ltd. All rights reserved.
ERIC Educational Resources Information Center
Light, Richard
2012-01-01
This article reports on a case study that inquired into the influence of the New South Wales Primary Schools Sports Association competitive swimming structure on the development of talented 12-year old female swimmers. The study focused on ten 12-year old girls in the New South Wales team that contested the 2009 national swimming championships…
The Backstroke Swimming Start: State of the Art
de Jesus, Karla; de Jesus, Kelly; Fernandes, Ricardo J.; Vilas-Boas, João Paulo; Sanders, Ross
2014-01-01
As sprint swimming events can be decided by margins as small as .01 s, thus, an effective start is essential. This study reviews and discusses the ‘state of the art’ literature regarding backstroke start biomechanics from 23 documents. These included two swimming specific publications, eight peer-reviewed journal articles, three from the Biomechanics and Medicine in Swimming Congress series, eight from the International Society of Biomechanics in Sports Conference Proceedings, one from a Biomechanics Congress and one academic (PhD) thesis. The studies had diverse aims, including swimmers’ proficiency levels and data collection settings. There was no single consensus for defining phase descriptions; and kinematics, kinetics and EMG approaches were implemented in laboratory settings. However, researchers face great challenges in improving methods of quantifying valid, reliable and accurate data between laboratory and competition conditions. For example, starting time was defined from the starting signal to distances as disparate as ∼5 m to 22.86 m in several studies. Due to recent rule changes, some of the research outcomes now refer to obsolete backstroke start techniques, and only a few studies considered the actual international rules. This literature review indicated that further research is required, in both laboratory and competition settings focusing on the combined influences of the current rules and block configuration on backstroke starting performances. PMID:25414737
Systemic and airway oxidative stress in competitive swimmers.
Škrgat, Sabina; Marčun, Robert; Kern, Izidor; Šilar, Mira; Šelb, Julij; Fležar, Matjaž; Korošec, Peter
2018-04-01
The environment in swimming pools, which contain chlorine, might interact with the airway epithelium, resulting in oxidative stress and/or inflammation during high intensity training periods. We evaluated pulmonary functional (metacholine challenge test, FEV1 and VC), cellular (eosinophils and neutrophils), inflammatory (FeNo, IL-5, IL-6, IL-8 and TNF-α), oxidative (8-isoprostanes) and angiogenesis factors (VEGF) in induced sputum and peripheral blood of 41 healthy non-asthmatic elite swimmers (median 16 years) during the period of high intensity training before a national championship. The second paired sampling was performed seven months later after training had been stopped for one month. There was a ten-fold increase (median 82-924 pg/ml; P < 0.001) in 8-isoprostanes in induced sputum and five-fold increase (median 82-924 pg/ml; P < 0.001) in sera during training in comparison to the period of rest. However, there was no difference in FEV1 (113 vs 116%), VC (119 vs 118%), FeNo (median 34 vs 38 ppb), eosinophils (2.7 vs 2.9% in sputum; 180 vs 165 cells/μl in blood), neutrophils, different cytokines or VEGF in induced sputum or sera. The only exception was TNF-α, which was moderately increased in sera (median 23 vs 40 pg/ml; P = 0.02) during the peak training period. Almost half (18 of 41) of swimmers showed bronchial hyperresponsiveness during the peak training period (PC20 cutoff was 4 mg/ml). There was no correlation between hyperresponsiveness and the markers of oxidative stress or inflammation. High intensity training in healthy, non-asthmatic competitive swimmers results in marked oxidative stress at the airway and systemic levels, but does not lead to airway inflammation. However, we could not confirm that oxidative stress is associated with bronchial hyperresponsiveness (AHR), which is often observed during the peak exercise training period. Copyright © 2018. Published by Elsevier Ltd.
Swim Free. A 10 Day Program of Aquatic Exercises Adapted from Life in the Waterworld.
ERIC Educational Resources Information Center
Eberhardt, Lorraine; Sanborn, Laura
The completely waterproof book contains instructions for an alternative form of swimming exercises based on the movements of 19 water creatures. The exercises can be used by groups or individuals to enhance training programs, to serve as part of a structured synchronized swimming program, or to supplement recreational activities. The book provides…
The key kinematic determinants of undulatory underwater swimming at maximal velocity.
Connaboy, Chris; Naemi, Roozbeh; Brown, Susan; Psycharakis, Stelios; McCabe, Carla; Coleman, Simon; Sanders, Ross
2016-01-01
The optimisation of undulatory underwater swimming is highly important in competitive swimming performance. Nineteen kinematic variables were identified from previous research undertaken to assess undulatory underwater swimming performance. The purpose of the present study was to determine which kinematic variables were key to the production of maximal undulatory underwater swimming velocity. Kinematic data at maximal undulatory underwater swimming velocity were collected from 17 skilled swimmers. A series of separate backward-elimination analysis of covariance models was produced with cycle frequency and cycle length as dependent variables (DVs) and participant as a fixed factor, as including cycle frequency and cycle length would explain 100% of the maximal swimming velocity variance. The covariates identified in the cycle-frequency and cycle-length models were used to form the saturated model for maximal swimming velocity. The final parsimonious model identified three covariates (maximal knee joint angular velocity, maximal ankle angular velocity and knee range of movement) as determinants of the variance in maximal swimming velocity (adjusted-r2 = 0.929). However, when participant was removed as a fixed factor there was a large reduction in explained variance (adjusted r2 = 0.397) and only maximal knee joint angular velocity continued to contribute significantly, highlighting its importance to the production of maximal swimming velocity. The reduction in explained variance suggests an emphasis on inter-individual differences in undulatory underwater swimming technique and/or anthropometry. Future research should examine the efficacy of other anthropometric, kinematic and coordination variables to better understand the production of maximal swimming velocity and consider the importance of individual undulatory underwater swimming techniques when interpreting the data.
Musculoskeletal injury review in the U.S. space program.
Jennings, R T; Bagian, J P
1996-08-01
Astronauts in NASA's space program are expected to remain fit to complete their on-orbit tasks and to function effectively in the event of contingency operations. Due to the generally self-directed exercise program and reliance on competitive sports and running for conditioning, plus limited emphasis on training techniques and rehabilitation, there have been a surprising number of orthopedic injuries and surgeries in this small adult population. This article examines the orthopedic injury history of U.S. astronauts during the period from 1987-95. The type of injury, activity involved, and subsequent surgical interventions are cataloged. There were a total of 26 fractures, 36 serious ligament, cartilage, or soft tissue injuries, and 28 orthopedic surgical procedures in this adult group with a mean astronaut corps size of only 94. Women accounted for 16% of the study population but accounted for only 1 of 28 surgical procedures. Knee injuries required surgical intervention 19 times. Running, skiing, and basketball were most frequently associated with injuries. The descriptive data regarding frequency of adverse events and activity associated with injuries is presented. These injury patterns are analyzed and suggestions made for future improvement, including decreased reliance on running and competitive athletics for conditioning, improved personal fitness training preflight, and coordinated rehabilitation postflight. Also recommended is the use of a lap pool for preflight total body fitness training, since swimming provides conditioning to those muscle groups used during spaceflight, and for variably weighted gravity rehabilitation postflight.
Using Tri-Axial Accelerometry in Daily Elite Swim Training Practice.
Ganzevles, Sander; Vullings, Rik; Beek, Peter Jan; Daanen, Hein; Truijens, Martin
2017-04-29
Background : Coaches in elite swimming carefully design the training programs of their swimmers and are keen on achieving strict adherence to those programs by their athletes. At present, coaches usually monitor the compliance of their swimmers to the training program with a stopwatch. However, this measurement clearly limits the monitoring possibilities and is subject to human error. Therefore, the present study was designed to examine the reliability and practical usefulness of tri-axial accelerometers for monitoring lap time, stroke count and stroke rate in swimming. Methods : In the first part of the study, a 1200 m warm-up swimming routine was measured in 13 elite swimmers using tri-axial accelerometers and synchronized video recordings. Reliability was determined using the typical error of measurement (TEM) as well as a Bland-Altman analysis. In the second part, training compliance both within and between carefully prescribed training sessions was assessed in four swimmers in order to determine the practical usefulness of the adopted accelerometric approach. In these sessions, targets were set for lap time and stroke count by the coach. Results : The results indicated high reliability for lap time (TEM = 0.26 s, bias = 0.74 [0.56 0.91] with limits of agreement (LoA) from -1.20 [-1.50 -0.90] to 2.70 [2.40 3.00]), stroke count (TEM 0.73 strokes, bias = 0.46 [0.32 0.60] with LoA from -1.70 [-1.94 -1.46] to 2.60 [2.36 2.84]) and stroke rate (TEM 0.72 str∙min -1 , bias = -0.13 [-0.20 -0.06] with LoA from -2.20 [-2.32 -2.08] to 1.90 [1.78 2.02]), while the results for the monitoring of training compliance demonstrated the practical usefulness of our approach in daily swimming training. Conclusions : The daily training of elite swimmers can be accurately and reliably monitored using tri-axial accelerometers. They provide the coach with more useful information to guide and control the training process than hand-clocked times.
Using Tri-Axial Accelerometry in Daily Elite Swim Training Practice
Ganzevles, Sander; Vullings, Rik; Beek, Peter Jan; Daanen, Hein; Truijens, Martin
2017-01-01
Background: Coaches in elite swimming carefully design the training programs of their swimmers and are keen on achieving strict adherence to those programs by their athletes. At present, coaches usually monitor the compliance of their swimmers to the training program with a stopwatch. However, this measurement clearly limits the monitoring possibilities and is subject to human error. Therefore, the present study was designed to examine the reliability and practical usefulness of tri-axial accelerometers for monitoring lap time, stroke count and stroke rate in swimming. Methods: In the first part of the study, a 1200 m warm-up swimming routine was measured in 13 elite swimmers using tri-axial accelerometers and synchronized video recordings. Reliability was determined using the typical error of measurement (TEM) as well as a Bland-Altman analysis. In the second part, training compliance both within and between carefully prescribed training sessions was assessed in four swimmers in order to determine the practical usefulness of the adopted accelerometric approach. In these sessions, targets were set for lap time and stroke count by the coach. Results: The results indicated high reliability for lap time (TEM = 0.26 s, bias = 0.74 [0.56 0.91] with limits of agreement (LoA) from −1.20 [−1.50 −0.90] to 2.70 [2.40 3.00]), stroke count (TEM 0.73 strokes, bias = 0.46 [0.32 0.60] with LoA from −1.70 [−1.94 −1.46] to 2.60 [2.36 2.84]) and stroke rate (TEM 0.72 str∙min−1, bias = −0.13 [−0.20 −0.06] with LoA from −2.20 [−2.32 −2.08] to 1.90 [1.78 2.02]), while the results for the monitoring of training compliance demonstrated the practical usefulness of our approach in daily swimming training. Conclusions: The daily training of elite swimmers can be accurately and reliably monitored using tri-axial accelerometers. They provide the coach with more useful information to guide and control the training process than hand-clocked times. PMID:28468255
Effects of Swimming Training on Stress Levels of the Students Aged 11-13
ERIC Educational Resources Information Center
Köroglu, Mihraç; Yigiter, Korkmaz
2016-01-01
The purpose of this research was to determine the effects of the swimming training program on stress levels of the students ages 11-13. To this end, 60 students from Private Sahin School in the Sakarya city participated in the study voluntarily. 60 students were divided into two groups and each group was included 30 students. Stress Level Scale II…
VO2 responses to intermittent swimming sets at velocity associated with VO2max.
Libicz, Sebastien; Roels, Belle; Millet, Gregoire P
2005-10-01
While the physiological adaptations following endurance training are relatively well understood, in swimming there is a dearth of knowledge regarding the metabolic responses to interval training (IT). The hypothesis tested predicted that two different endurance swimming IT sets would induce differences in the total time the subjects swam at a high percentage of maximal oxygen consumption (VO(2)max). Ten trained triathletes underwent an incremental test to exhaustion in swimming so that the swimming velocity associated with VO(2)max (vVO(2)max) could be determined. This was followed by a maximal 400-m test and two intermittent sets at vVO(2)max: (a) 16 x 50 m with 15-s rest (IT(50)); (b) 8 x 100 m with 30-s rest (IT(100)). The times sustained above 95% VO(2)max (68.50 +/- 62.69 vs. 145.01 +/- 165.91 sec) and 95% HRmax (146.67 +/- 131.99 vs. 169.78 +/- 203.45 sec, p = 0.54) did not differ between IT(50) and IT(100)(values are mean +/- SD). In conclusion, swimming IT sets of equal time duration at vVO(2)max but of differing work-interval durations led to slightly different VO(2)and HR responses. The time spent above 95% of VO(2)max was twice as long in IT(100) as in IT (50), and a large variability between mean VO(2)and HR values was also observed.
Clemente-Suárez, Vicente Javier; Delgado-Moreno, Rosa; González, Beatriz; Ortega, Javier; Ramos-Campo, Domingo Jesús
2018-04-12
The aim of the present research was to compare the effects in swimming and running performance, horizontal jump test, autonomic modulation, and body composition of four training weeks with emphasis on volume versus intensity in moderate trained triathletes. Thirty-two amateur triathletes (20 males and 12 females) were randomly divided in three different groups that performed 6 training session per week: Intensity (INT): training focused on performs intensity training Volume (VOL): training focused on performs volume training; and Control (CON): physical active group with no periodized training. Body composition, heart rate variability, horizontal jump test, swimming and 2000 m running test were tested before and after the training period. There were no significant differences between INT and VOL in running test. Furthermore, both INT and VOL training groups improved 50 m (p: 0.046 and 0.042 respectively) and 400 m (p: 0.044 and 0.041 respectively) swimming performance. Moreover, there were no significant differences among groups in any moment in HRV variables. No significant difference was observed for horizontal jump test and body composition between the INT and VOL group at any time. According to the results of the present study, four weeks of training with either high intensity or volume results to similar adaptations in endurance, horizontal jump test and body composition parameters in amateur triathletes. Copyright © 2018. Published by Elsevier Inc.
Implicit measures of beliefs about sport ability in swimming and basketball.
Mascret, Nicolas; Falconetti, Jean-Louis; Cury, François
2016-01-01
Sport ability may be seen as relatively stable, genetically determined and not easily modified by practice, or as increasable with training, work and effort. Using the Implicit Association Test (IAT), the purpose of the present study is to examine whether the practice of a particular sport (swimming or basketball) can influence automatic beliefs about sport ability in these two sports. The IAT scores evidence that swimmers and basketball players automatically and implicitly associate their own sport with training rather than genetics, whereas non-sportspersons have no significant automatic association. This result is strengthened when perceived competence and intrinsic motivation in swimming or basketball are high.
Palazzetti, S; Margaritis, I; Guezennec, C Y
2005-04-01
The aim of the study was to verify whether an overloaded training (OT) in triathlon deteriorates running kinematics (RK) and running economy (RE). Thirteen well-trained male long-distance triathletes (age: 28.1 +/- 4.3 yrs; V.O (2max): 65.0 +/- 3.1 ml O (2) . min (-1) . kg (-1)) were divided into two groups: completed an individualized OT program (OG; n = 7) or maintained a normal level of training (NT) (CG; n = 6) for a duration of 3 weeks. Every week, each triathlete completed a standardized questionnaire to quantify the influence of training loads on mood state. To reach OT, total training load (h . 3 wk (-1)) was increased by 24 %; swimming and cycling total volumes were increased by 46 and 57 %, respectively, but the distance run was not modified in order to limit the risk of injuries. RK and RE were determined on treadmill test at 12 km . h (-1) before and after the 3 weeks. The 3-week swimming and cycling OT in triathlon was sufficiently stressful to alter mood state but not to deteriorate the running kinematics and economy parameters in our previously well-trained male long-distance triathletes.
Transient enhancement of GLUT-4 levels in rat epitrochlearis muscle after exercise training
Reynolds, Thomas H.; Brozinick, Joseph T.; Larkin, Lisa M.; Cushman, Samuel W.
2009-01-01
The purpose of the present study was to examine the effect of detraining on the glucose transport system after short-term swim training (5 days), long-term swim training (5 wk), and treadmill run training (5 wk). Skeletal muscles were isolated from female Wistar rats at 24 or 48 h posttraining. SST produces a 48% increase in GLUT-4 mRNA, a 30% increase in GLUT-4 protein, and a 60% increase in insulin-stimulated glucose transport activity at 24 h posttraining but not at 48 h posttraining. Similar to SST, long-term swim training produces a 60% increase in GLUT-4 mRNA and a 30% increase in GLUT-4 protein content at 24 h posttraining but not at 48 h posttraining. Finally, treadmill run training produces a transient 35% increase in GLUT-4 protein content that is completely reversed at 48 h after the last bout of exercise. These results demonstrate that the increase in GLUT-4 mRNA and GLUT-4 protein occurs during the first week of exercise training and is rapidly lost after training cessation. We believe that the transient enhancement in GLUT-4 protein after exercise training is due to a short GLUT-4 half-life, a process that is primarily regulated by pretranslational mechanisms. PMID:10846041
Transient enhancement of GLUT-4 levels in rat epitrochlearis muscle after exercise training.
Reynolds, T H; Brozinick, J T; Larkin, L M; Cushman, S W
2000-06-01
The purpose of the present study was to examine the effect of detraining on the glucose transport system after short-term swim training (5 days), long-term swim training (5 wk), and treadmill run training (5 wk). Skeletal muscles were isolated from female Wistar rats at 24 or 48 h posttraining. SST produces a 48% increase in GLUT-4 mRNA, a 30% increase in GLUT-4 protein, and a 60% increase in insulin-stimulated glucose transport activity at 24 h posttraining but not at 48 h posttraining. Similar to SST, long-term swim training produces a 60% increase in GLUT-4 mRNA and a 30% increase in GLUT-4 protein content at 24 h posttraining but not at 48 h posttraining. Finally, treadmill run training produces a transient 35% increase in GLUT-4 protein content that is completely reversed at 48 h after the last bout of exercise. These results demonstrate that the increase in GLUT-4 mRNA and GLUT-4 protein occurs during the first week of exercise training and is rapidly lost after training cessation. We believe that the transient enhancement in GLUT-4 protein after exercise training is due to a short GLUT-4 half-life, a process that is primarily regulated by pretranslational mechanisms.
Swim training and the genetic expression of adipokines in monosodium glutamate-treated obese rats.
Svidnicki, Paulo Vinicius; Leite, Nayara Carvalho; Vicari, Marcelo Ricardo; Almeida, Mara Cristina de; Artoni, Roberto Ferreira; Favero, Giovani Marino; Grassiolli, Sabrina; Nogaroto, Viviane
2015-06-01
The aim of this study was to evaluate the genetic expression of adipokines in the adipocytes of monosodium glutamate (MSG)-treated obese rats submitted to physical activity. Obesity was induced by neonatal MSG administration. Exercised rats (MSG and control) were subjected to swim training for 30 min for 10 weeks, whereas their respective controls remained sedentary. Total RNA was obtained from sections of the mesenteric adipose tissue of the rats. mRNA levels of adiponectin (Adipoq), tumor necrosis factor alpha (Tnf), peroxisome proliferator-activated receptor alpha (Ppara), and peroxisome proliferator-activated receptor gamma (Pparg) adipokines were quantified by quantitative Real-Time Polymerase Chain Reaction (qRT-PCR). In the exercise-trained control group, the expression of Adipoq increased compared to the sedentary control, which was not observed in the MSG-obese rats. Increased levels of Tnf in MSG-obese rats were not reversed by the swim training. The expression of Ppara was higher in sedentary MSG-obese rats compared to the sedentary control. Swimming increased this adipokine expression in the exercise-trained control rats compared to the sedentary ones. mRNA levels of Pparg were higher in the sedentary MSG-rats compared to the sedentary control; however, the exercise did not influenced its expression in the groups analyzed. In conclusion, regular physical activity was not capable to correct the expression of proinflammatory adipokines in MSG-obese rat adipocytes.
Lätt, Evelin; Jürimäe, Jaak; Mäestu, Jarek; Purge, Priit; Rämson, Raul; Haljaste, Kaja; Keskinen, Kari L; Rodriguez, Ferran A; Jürimäe, Toivo
2010-01-01
The purpose of this study was to analyze the relationships between 100-m front crawl swimming performance and relevant biomechanical, anthropometrical and physiological parameters in male adolescent swimmers. Twenty five male swimmers (mean ± SD: age 15. 2 ± 1.9 years; height 1.76 ± 0.09 m; body mass 63.3 ± 10.9 kg) performed an all-out 100-m front crawl swimming test in a 25-m pool. A respiratory snorkel and valve system with low hydrodynamic resistance was used to collect expired air. Oxygen uptake was measured breath-by-breath by a portable metabolic cart. Swimming velocity, stroke rate (SR), stroke length and stroke index (SI) were assessed during the test by time video analysis. Blood samples for lactate measurement were taken from the fingertip pre exercise and at the third and fifth minute of recovery to estimate net blood lactate accumulation (ΔLa). The energy cost of swimming was estimated from oxygen uptake and blood lactate energy equivalent values. Basic anthropometry included body height, body mass and arm span. Body composition parameters were measured using dual-energy X-ray absorptiometry (DXA). Results indicate that biomechanical factors (90.3%) explained most of 100-m front crawl swimming performance variability in these adolescent male swimmers, followed by anthropometrical (45.8%) and physiological (45.2%) parameters. SI was the best single predictor of performance, while arm span and ∆La were the best anthropometrical and physiological indicators, respectively. SI and SR alone explained 92.6% of the variance in competitive performance. These results confirm the importance of considering specific stroke technical parameters when predicting success in young swimmers. Key pointsThis study investigated the influence of different anthropometrical, physiological and biomechanical parameters on 100-m swimming performance in adolescent boys.Biomechanical factors contributed most to sprint swimming performance in these young male swimmers (90.3% of variability in performance), followed by anthropometrical (45.8%) and physiological (45.2%) parameters.Two selected variables (stroke index and stroke rate) explained 92.6% of the variance in competitive performance in these adolescent swimmers.
Lätt, Evelin; Jürimäe, Jaak; Mäestu, Jarek; Purge, Priit; Rämson, Raul; Haljaste, Kaja; Keskinen, Kari L.; Rodriguez, Ferran A.; Jürimäe, Toivo
2010-01-01
The purpose of this study was to analyze the relationships between 100-m front crawl swimming performance and relevant biomechanical, anthropometrical and physiological parameters in male adolescent swimmers. Twenty five male swimmers (mean ± SD: age 15. 2 ± 1.9 years; height 1.76 ± 0.09 m; body mass 63.3 ± 10.9 kg) performed an all-out 100-m front crawl swimming test in a 25-m pool. A respiratory snorkel and valve system with low hydrodynamic resistance was used to collect expired air. Oxygen uptake was measured breath-by-breath by a portable metabolic cart. Swimming velocity, stroke rate (SR), stroke length and stroke index (SI) were assessed during the test by time video analysis. Blood samples for lactate measurement were taken from the fingertip pre exercise and at the third and fifth minute of recovery to estimate net blood lactate accumulation (ΔLa). The energy cost of swimming was estimated from oxygen uptake and blood lactate energy equivalent values. Basic anthropometry included body height, body mass and arm span. Body composition parameters were measured using dual-energy X-ray absorptiometry (DXA). Results indicate that biomechanical factors (90.3%) explained most of 100-m front crawl swimming performance variability in these adolescent male swimmers, followed by anthropometrical (45.8%) and physiological (45.2%) parameters. SI was the best single predictor of performance, while arm span and ∆La were the best anthropometrical and physiological indicators, respectively. SI and SR alone explained 92.6% of the variance in competitive performance. These results confirm the importance of considering specific stroke technical parameters when predicting success in young swimmers. Key points This study investigated the influence of different anthropometrical, physiological and biomechanical parameters on 100-m swimming performance in adolescent boys. Biomechanical factors contributed most to sprint swimming performance in these young male swimmers (90.3% of variability in performance), followed by anthropometrical (45.8%) and physiological (45.2%) parameters. Two selected variables (stroke index and stroke rate) explained 92.6% of the variance in competitive performance in these adolescent swimmers. PMID:24149633
Svidnicki, P V; de Carvalho Leite, N; Venturelli, A C; Camargo, R L; Vicari, M R; de Almeida, M C; Artoni, R F; Nogaroto, V; Grassiolli, S
2013-09-01
Glucagon-like peptide-1 (GLP-1) is an important modulator of insulin secretion by endocrine pancreas. In the present study, we investigated the effect of swim training on GLP-1 insulinotropic action in pancreatic islets from monosodium glutamate (MSG)-obese rats. Obesity was induced by neonatal MSG administration. MSG-obese and control (CON) exercised rats swam for 30 min (3 times week(-1) ) for 10 weeks. Pancreatic islets were isolated by colagenase technique and incubated with low (5.6 mM) or high (16.7 mM) glucose concentrations in the presence or absence of GLP-1 (10 nM). In addition, GLP-1 gene expression in ileum was quantified in fasting and glucose conditions. Exercise reduced obesity and hyperinsulinemia in MSG-obese rats. Swim training also inhibited glucose-induced insulin secretion in islets from both groups. Islets from MSG-obese rats maintained GLP-1 insulinotropic response in low glucose concentration. In contrast, in the presence of high glucose concentration, GLP-1 insulinotropic action was absent in islets from MSG-obese rats. Islets from MSG-exercised rats showed reduced GLP-1 insulinotropic action in the presence of low glucose. However, in high glucose concentration swim training restored GLP-1 insulinotropic response in islets from MSG-obese rats. In all groups, glucose intake increased GLP-1 immunoreactivity and gene expression in ileum cells in relation to fasting conditions. Swim training reduced these parameters only in ileum cells from CON-exercised rats. Neither MSG treatment nor exercise affected GLP-1 expression in the ileum. Exercise avoids insulin hypersecretion restoring GLP-1's insulinotropic action in pancreatic islets from MSG-obese rats. © 2013 Scandinavian Physiological Society. Published by John Wiley & Sons Ltd.
Fluid Dynamics of Competitive Swimming: A Computational Study
NASA Astrophysics Data System (ADS)
Mittal, Rajat; Loebbeck, Alfred; Singh, Hersh; Mark, Russell; Wei, Timothy
2004-11-01
The dolphin kick is an important component in competitive swimming and is used extensively by swimmers immediately following the starting dive as well as after turns. In this stroke, the swimmer swims about three feet under the water surface and the stroke is executed by performing an undulating wave-like motion of the body that is quite similar to the anguilliform propulsion mode in fish. Despite the relatively simple kinematics of this stoke, considerable variability in style and performance is observed even among Olympic level swimmers. Motivated by this, a joint experimental-numerical study has been initiated to examine the fluid-dynamics of this stroke. The current presentation will describe the computational portion of this study. The computations employ a sharp interface immersed boundary method (IBM) which allows us to simulate flows with complex moving boudnaries on stationary Cartesian grids. 3D body scans of male and female Olympic swimmers have been obtained and these are used in conjuction with high speed videos to recreate a realistic dolphin kick for the IBM solver. Preliminary results from these computations will be presented.
Collaborative Undergraduate HBCU Student Summer Training Program Award
2011-06-01
Iowa. These include exercise facilities (running, tennis, basketball, volleyball, handball /racquetball, weights, biking, and swimming), local...basketball, volleyball, handball /racquetball, weights, biking, and swimming), local beaches, and museums (art, natural history, and sports). In
Locomotion of bacteria in liquid flow and the boundary layer effect on bacterial attachment.
Zhang, Chao; Liao, Qiang; Chen, Rong; Zhu, Xun
2015-06-12
The formation of biofilm greatly affects the performance of biological reactors, which highly depends on bacterial swimming and attachment that usually takes place in liquid flow. Therefore, bacterial swimming and attachment on flat and circular surfaces with the consideration of flow was studied experimentally. Besides, a mathematical model comprehensively combining bacterial swimming and motion with flow is proposed for the simulation of bacterial locomotion and attachment in flow. Both experimental and theoretical results revealed that attached bacteria density increases with decreasing boundary layer thickness on both flat and circular surfaces, the consequence of which is inherently related to the competition between bacterial swimming and the non-slip motion with flow evaluated by the Péclet number. In the boundary layer, where the Péclet number is relatively higher, bacterial locomotion mainly depends on bacterial swimming. Thinner boundary layer promotes bacterial swimming towards the surface, leading to higher attachment density. To enhance the performance of biofilm reactors, it is effective to reduce the boundary layer thickness on desired surfaces. Copyright © 2015 Elsevier Inc. All rights reserved.
Analysis of injuries in long-distance triathletes.
Egermann, M; Brocai, D; Lill, C A; Schmitt, H
2003-05-01
Triathlon is an individual sport consisting of three disciplines - swimming, cycling and running. Triathlon has changed from a novel appearance to a very popular Olympic sport within the last fifteen years. Nevertheless, there is not sufficient data about injuries in triathlon. The aim of this retrospective survey was to investigate the incidence of injuries according to class of injuries, anatomical sites and disciplines. Relations to age, sex, performance level, training habits and medical care were analysed. Questionnaires were sent to all German speaking participants of the Ironman Europe 2000. With a response rate of 35 %, 656 questionnaires met the inclusion criteria. At least one injury was experienced by 74.8 % (95 %-CI: 71.3-78.1) of all respondents during their active time in triathlon. 51.1 % (95 %-CI: 47.2-55.0) suffered one or more contusion/skin-abrasions, 33.1 % (95 %-CI: 29.5-36.8) muscle-/tendon-injuries, 29.0 % (95 %-CI: 25.5-32.6) ligament-/capsule-injuries and 11.9 % (95 %-CI: 9.5-14.6) fractures. Most of the injuries happened during cycling (54.8 % [95 %-CI: 51.9-57.8]) within training sessions. 18.7 % (95 %-CI: 16.4-21.2) of all injuries occurred while the athletes were competing. Considering the low number of competition hours per year, the incidence of injuries during competition was higher than during training session. Significant relations were found considering the age, performance level and weekly training hours of the triathletes. Older athletes sustained more fractures (p = 0.024), high performance athletes suffered more contusions/abrasions (p = 0.003) and muscle-tendon-injuries (p = 0.001) and athletes with a large number of weekly training hours suffered more muscle-tendon-injuries (p = 0.014). To summarize, injuries in triathlon seem to be related to age, performance level and weekly training hours, but not to sex, presence of training coach and medical care.
Delineating the roles of males and females in sperm competition
Evans, Jonathan P.; Rosengrave, Patrice; Gasparini, Clelia; Gemmell, Neil J.
2013-01-01
Disentangling the relative roles of males, females and their interactive effects on competitive fertilization success remains a challenge in sperm competition. In this study, we apply a novel experimental framework to an ideally suited externally fertilizing model system in order to delineate these roles. We focus on the chinook salmon, Oncorhynchus tshawytscha, a species in which ovarian fluid (OF) has been implicated as a potential arbiter of cryptic female choice for genetically compatible mates. We evaluated this predicted sexually selected function of OF using a series of factorial competitive fertilization trials. Our design involved a series of 10 factorial crosses, each involving two ‘focal’ rival males whose sperm competed against those from a single ‘standardized’ (non-focal) rival for a genetically uniform set of eggs in the presence of OF from two focal females. This design enabled us to attribute variation in competitive fertilization success among focal males, females (OF) and their interacting effects, while controlling for variation attributable to differences in the sperm competitive ability of rival males, and male-by-female genotypic interactions. Using this experimental framework, we found that variation in sperm competitiveness could be attributed exclusively to differences in the sperm competitive ability of focal males, a conclusion supported by subsequent analyses revealing that variation in sperm swimming velocity predicts paternity success. Together, these findings provide evidence that variation in paternity success can be attributed to intrinsic differences in the sperm competitive ability of rival males, and reveal that sperm swimming velocity is a key target of sexual selection. PMID:24266039
Mukherjee, Tanmoy; Kumar, Dhivya; Burriss, Nathan; Xie, Zhihong
2016-01-01
ABSTRACT The genomes of most motile bacteria encode two or more chemotaxis (Che) systems, but their functions have been characterized in only a few model systems. Azospirillum brasilense is a motile soil alphaproteobacterium able to colonize the rhizosphere of cereals. In response to an attractant, motile A. brasilense cells transiently increase swimming speed and suppress reversals. The Che1 chemotaxis pathway was previously shown to regulate changes in the swimming speed, but it has a minor role in chemotaxis and root surface colonization. Here, we show that a second chemotaxis system, named Che4, regulates the probability of swimming reversals and is the major signaling pathway for chemotaxis and wheat root surface colonization. Experimental evidence indicates that Che1 and Che4 are functionally linked to coordinate changes in the swimming motility pattern in response to attractants. The effect of Che1 on swimming speed is shown to enhance the aerotactic response of A. brasilense in gradients, likely providing the cells with a competitive advantage in the rhizosphere. Together, the results illustrate a novel mechanism by which motile bacteria utilize two chemotaxis pathways regulating distinct motility parameters to alter movement in gradients and enhance the chemotactic advantage. IMPORTANCE Chemotaxis provides motile bacteria with a competitive advantage in the colonization of diverse niches and is a function enriched in rhizosphere bacterial communities, with most species possessing at least two chemotaxis systems. Here, we identify the mechanism by which cells may derive a significant chemotactic advantage using two chemotaxis pathways that ultimately regulate distinct motility parameters. PMID:27068592
Mukherjee, Tanmoy; Kumar, Dhivya; Burriss, Nathan; Xie, Zhihong; Alexandre, Gladys
2016-06-15
The genomes of most motile bacteria encode two or more chemotaxis (Che) systems, but their functions have been characterized in only a few model systems. Azospirillum brasilense is a motile soil alphaproteobacterium able to colonize the rhizosphere of cereals. In response to an attractant, motile A. brasilense cells transiently increase swimming speed and suppress reversals. The Che1 chemotaxis pathway was previously shown to regulate changes in the swimming speed, but it has a minor role in chemotaxis and root surface colonization. Here, we show that a second chemotaxis system, named Che4, regulates the probability of swimming reversals and is the major signaling pathway for chemotaxis and wheat root surface colonization. Experimental evidence indicates that Che1 and Che4 are functionally linked to coordinate changes in the swimming motility pattern in response to attractants. The effect of Che1 on swimming speed is shown to enhance the aerotactic response of A. brasilense in gradients, likely providing the cells with a competitive advantage in the rhizosphere. Together, the results illustrate a novel mechanism by which motile bacteria utilize two chemotaxis pathways regulating distinct motility parameters to alter movement in gradients and enhance the chemotactic advantage. Chemotaxis provides motile bacteria with a competitive advantage in the colonization of diverse niches and is a function enriched in rhizosphere bacterial communities, with most species possessing at least two chemotaxis systems. Here, we identify the mechanism by which cells may derive a significant chemotactic advantage using two chemotaxis pathways that ultimately regulate distinct motility parameters. Copyright © 2016, American Society for Microbiology. All Rights Reserved.
ASCANs Helms and Gregory swim in pool during Elgin AFB survival training
1990-09-20
1990 Group 13 Astronaut Candidates (ASCANs) Susan J. Helms (foreground) and William G. Gregory, wearing helmets and flight suits, swim in pool at Elgin Air Force Base (AFB) in Pensacola, Florida, during water survival exercises. The training familiarized the candidates with survival techniques necessary in the event of a water landing. ASCANs participated in the exercises from 08-14-90 through 08-17-90.
Autonomic adaptation after traditional and reverse swimming training periodizations.
Clemente-Suárez, Vicente Javier; Fernandes, R J; Arroyo-Toledo, J J; Figueiredo, P; González-Ravé, J M; Vilas-Boas, J P
2015-03-01
The objective of the present study was to analyze the autonomic response of trained swimmers to traditional and reverse training periodization models. Seventeen swimmers were divided in two groups, performing a traditional periodization (TPG) or a reverse periodization (RPG) during a period of 10 weeks. Heart rate variability and 50 m swimming performance were analyzed before and after the training programs. After training, the TPG decreased the values of the high frequency band (HF), the number of differences between adjacent normal R-R intervals longer than 50 ms (NN50) and the percentage of differences between adjacent normal R-R intervals more than 50 ms (pNN50), and the RPG increased the values of HF and square root of the mean of the sum of the squared differences between adjacent normal R-R intervals (RMSSD). None of the groups improved significantly their performance in the 50-m test. The autonomic response of swimmers was different depending on the periodization performed, with the reverse periodization model leading to higher autonomic adaption. Complementary, the data suggests that autonomic adaptations were not critical for the 50-m swimming performance.
Use of Biotechnology Devices to Analyse Fatigue Process in Swimming Training.
Clemente-Suárez, V J; Arroyo-Toledo, J J
2017-06-01
The aim of the present research was to analyze the acute psycho-physiological response during a high intensity interval training (HIIT) session of trained swimmers. We analyzed blood lactate concentration, heart rate, heart rate variability (HRV), arms isometric strength, rating of perceived exertion (RPE) and cortical arousal before and after a HIIT session in 14 trained swimmers (16.2 ± 2.6 years 169.1 ± 10.2 cm 61.3 ± 9.9 kg). HIIT session consisted in: 4 × 10 m tethered swimming resting 90 s between sets, 3 min rest, 16 × 25 m maximum speed swimming resting 30 s between sets. Blood lactate concentration, cortical arousal, and rating of perceived exertion significantly increased (p < 0.05) after HIIT. HRV parameters significantly decreased after HIIT, showing an increase in sympathetic nervous system modulation. Results obtained showed the high impact of HIIT sessions on the swimmer's organism, which may be the cause of adaptation in this low volume training sessions.
Further evidence for conditioned taste aversion induced by forced swimming.
Masaki, Takahisa; Nakajima, Sadahiko
2005-01-31
A series of experiments with rats reported that aversion to a taste solution can be established by forced swimming in a water pool. Experiment 1 demonstrated that correlation of taste and swimming is a critical factor for this phenomenon, indicating associative (i.e., Pavlovian) nature of this learning. Experiment 2 showed that this learning obeys the Pavlovian law of strength, by displaying a positive relationship between the duration of water immersion in training and the taste aversion observed in subsequent testing. Experiment 3 revealed that swimming rather than being wet is the critical agent, because a water shower did not endow rats with taste aversion. Experiment 4 found that taste aversion was a positive function of water level of the pools in training (0, 12 or 32 cm). These results, taken together, suggest that energy expenditure caused by physical exercise might be involved in the development of taste aversion.
Diagnosis of Swimming Induced Pulmonary Edema—A Review
Grünig, Hannes; Nikolaidis, Pantelis T.; Moon, Richard E.; Knechtle, Beat
2017-01-01
Swimming induced pulmonary edema (SIPE) is a complication that can occur during exercise with the possibility of misdiagnosis and can quickly become life threatening; however, medical literature infrequently describes SIPE. Therefore, the aim of this review was to analyse all individual cases diagnosed with SIPE as reported in scientific sources, with an emphasis on the diagnostic pathways and the key facts resulting in its diagnosis. Due to a multifactorial and complicated pathophysiology, the diagnosis could be difficult. Based on the actual literature, we try to point out important findings regarding history, conditions, clinical findings, and diagnostic testing helping to confirm the diagnosis of SIPE. Thirty-eight cases from seventeen articles reporting the diagnosis of SIPE were selected. We found remarkable differences in the individual described diagnostic pathways. A total of 100% of the cases suffered from an acute onset of breathing problems, occasionally accompanied by hemoptysis. A total of 73% showed initial hypoxemia. In most of the cases (89%), an initial chest X-Ray or chest CT was available, of which one-third (71%) showed radiological signs of pulmonary edema. The majority of the cases (82%) experienced a rapid resolution of symptoms within 48 h, the diagnostic hallmark of SIPE. Due to a foreseeable increase in participation in swimming competitions and endurance competitions with a swimming component, diagnosis of SIPE will be important, especially for medical teams caring for these athletes. PMID:28912730
Effect of aerobic training on inter-arm coordination in highly trained swimmers.
Schnitzler, Christophe; Seifert, Ludovic; Chollet, Didier; Toussaint, Huub
2014-02-01
The effect of three months of aerobic training on spatio-temporal and coordination parameters was examined during a swim trial at maximal aerobic speed. Nine male swimmers swam a 400-m front crawl at maximal speed twice: in trial 1, after summer break, and trial 2, after three months of aerobic training. Video analysis determined the stroke (swimming speed, stroke length, and stroke rate) and coordination (Index of Coordination and propulsive phase duration) parameters for every 50-m segment. All swimmers significantly increased their swimming speed after training. For all swimmers except one, stroke length increased and stroke rate remained constant, whereas the Index of Coordination and the propulsive phase duration decreased (p<.05). This study suggests that aerobic training developed a greater force impulse in the swimmers during the propulsive phases, which allowed them to take advantage of longer non-propulsive phases. In this case, catch-up coordination, if associated with greater stroke length, can be an efficient coordination mode that reflects optimal drag/propulsion adaptation. This finding thus provides new insight into swimmers' adaptations to the middle-distance event. Copyright © 2013 Elsevier B.V. All rights reserved.
Assessment of muscle fatigue using electromygraphm sensing
NASA Astrophysics Data System (ADS)
Helmi, Muhammad Hazimin Bin; Ping, Chew Sue; Ishak, Nur Elliza Binti; Saad, Mohd Alimi Bin Mohd; Mokhtar, Anis Shahida Niza Binti
2017-08-01
Muscle fatigue is condition of muscle decline in ability after undergoing any physical activity. Observation of the muscle condition of an athlete during training is crucial to prevent or minimize injury and able to achieve optimum performance in actual competition. The aim of this project is to develop a muscle monitoring system to detect muscle fatigue in swimming athlete. This device is capable to measure muscle stress level of the swimmer and at the same time provide indication of muscle fatigue level to trainer. Electromyography signal was recorded from the muscle movement while practicing the front crawl stroke repetitively. The time domain data was processed to frequency spectra in order to study the effect of muscle fatigue. The results show that the recorded EMG signal is able to sense muscle fatigue.
Mohr, Magni; Nordsborg, Nikolai Baastrup; Lindenskov, Annika; Steinholm, Hildigunn; Nielsen, Hans Petur; Mortensen, Jann; Weihe, Pal; Krustrup, Peter
2014-01-01
To test the hypothesis that high-intensity swim training improves cardiovascular health status in sedentary premenopausal women with mild hypertension, sixty-two women were randomized into high-intensity (n = 21; HIT), moderate-intensity (n = 21; MOD), and control groups (n = 20; CON). HIT performed 6-10 × 30 s all-out swimming interspersed by 2 min recovery and MOD swam continuously for 1 h at moderate intensity for a 15-week period completing in total 44 ± 1 and 43 ± 1 sessions, respectively. In CON, all measured variables were similar before and after the intervention period. Systolic BP decreased (P < 0.05) by 6 ± 1 and 4 ± 1 mmHg in HIT and MOD; respectively. Resting heart rate declined (P < 0.05) by 5 ± 1 bpm both in HIT and MOD, fat mass decreased (P < 0.05) by 1.1 ± 0.2 and 2.2 ± 0.3 kg, respectively, while the blood lipid profile was unaltered. In HIT and MOD, performance improved (P < 0.05) for a maximal 10 min swim (13 ± 3% and 22 ± 3%), interval swimming (23 ± 3% and 8 ± 3%), and Yo-Yo IE1 running performance (58 ± 5% and 45 ± 4%). In conclusion, high-intensity intermittent swimming is an effective training strategy to improve cardiovascular health and physical performance in sedentary women with mild hypertension. Adaptations are similar with high- and moderate-intensity training, despite markedly less total time spent and distance covered in the high-intensity group.
Mohr, Magni; Nordsborg, Nikolai Baastrup; Lindenskov, Annika; Steinholm, Hildigunn; Nielsen, Hans Petur; Mortensen, Jann; Weihe, Pal; Krustrup, Peter
2014-01-01
To test the hypothesis that high-intensity swim training improves cardiovascular health status in sedentary premenopausal women with mild hypertension, sixty-two women were randomized into high-intensity (n = 21; HIT), moderate-intensity (n = 21; MOD), and control groups (n = 20; CON). HIT performed 6–10 × 30 s all-out swimming interspersed by 2 min recovery and MOD swam continuously for 1 h at moderate intensity for a 15-week period completing in total 44 ± 1 and 43 ± 1 sessions, respectively. In CON, all measured variables were similar before and after the intervention period. Systolic BP decreased (P < 0.05) by 6 ± 1 and 4 ± 1 mmHg in HIT and MOD; respectively. Resting heart rate declined (P < 0.05) by 5 ± 1 bpm both in HIT and MOD, fat mass decreased (P < 0.05) by 1.1 ± 0.2 and 2.2 ± 0.3 kg, respectively, while the blood lipid profile was unaltered. In HIT and MOD, performance improved (P < 0.05) for a maximal 10 min swim (13 ± 3% and 22 ± 3%), interval swimming (23 ± 3% and 8 ± 3%), and Yo-Yo IE1 running performance (58 ± 5% and 45 ± 4%). In conclusion, high-intensity intermittent swimming is an effective training strategy to improve cardiovascular health and physical performance in sedentary women with mild hypertension. Adaptations are similar with high- and moderate-intensity training, despite markedly less total time spent and distance covered in the high-intensity group. PMID:24812628
When Is It Too Early for Single Sport Specialization?
Feeley, Brian T; Agel, Julie; LaPrade, Robert F
2016-01-01
Over the past 15 years, there has been an increase in youth sports participation with a concomitant increase in early year-round training in a single sport. Many factors contribute to the desire of parents and coaches to encourage early single sport specialization, including the desire to give the young athlete an edge in competition, pursuit of scholarships, and potential professional status, and the ability to label a young athlete as elite at an early age. Despite these perceived advantages, some data suggest that early sport specialization does not lead to a competitive advantage over athletes who participate in multiple sports. Although the data are limited, there is some evidence that early sport specialization may put the young athlete at risk for overuse injuries. The focus of this review is to highlight the evidence regarding early sport specialization and risk for injury; discuss the risk factors for overuse injury in high-risk sports including ice hockey, swimming, gymnastics, and baseball; and discuss future potential research that would help define the risk of injury for young athletes who participate in early sport specialization. © 2015 The Author(s).
ERIC Educational Resources Information Center
Sallayici, Mustafa; Eroglu Kolayis, Ipek; Kesilmis, Inci; Kesilmis, Mehmet Melih
2018-01-01
The objective of this study was to examine athletes' anxiety, motivation, and imagination value in competitions with different severity level. The research was conducted on swimming athlete in elite level 18 female and 19 male totally 37. To measure the level of imagination, imagine inventory in sports and to measure trait anxiety levels STAI were…
Banks, Kevin P; Ly, Justin Q; Beall, Douglas P; Grayson, David E; Bancroft, Laura W; Tall, Michael A
2005-01-01
Overuse injuries are a very common cause of pain in athletes, accounting for a significant loss of training time and missed competitions. Magnetic resonance imaging (MRI) is playing an increasing role in facilitating the expeditious and safe return of these individuals to their preinjury level of physical performance by allowing accurate diagnosis. Sports physicians are increasingly relying on the exquisite anatomic detail afforded by this technique to formulate diagnoses that assist with the optimal management of these athletic injuries. Some upper extremity overuse entities are well recognized; two examples are medial epicondylitis, classically appearing in baseball pitchers, and lateral epicondylitis, in tennis players. Other less well-known injuries of the upper extremity, such as intersection syndrome in rowers and distal clavicular stress fractures in weightlifters, are frequent occurrences in certain circles of athletes. The following article is a pictorial review of the MRI findings of upper extremity overuse injuries encountered in the competitive athlete, with an emphasis on the sports scenarios in which they occur. We will depict mechanisms of injury and applicable anatomy and show characteristic imaging findings. A wide range of entities are addressed, including but not limited to overuse injuries occurring in baseball, swimming, gymnastics, weightlifting, bowling, and cycling.
Respiratory muscle specific warm-up and elite swimming performance.
Wilson, Emma E; McKeever, Tricia M; Lobb, Claire; Sherriff, Tom; Gupta, Luke; Hearson, Glenn; Martin, Neil; Lindley, Martin R; Shaw, Dominick E
2014-05-01
Inspiratory muscle training has been shown to improve performance in elite swimmers, when used as part of routine training, but its use as a respiratory warm-up has yet to be investigated. To determine the influence of inspiratory muscle exercise (IME) as a respiratory muscle warm-up in a randomised controlled cross-over trial. A total of 15 elite swimmers were assigned to four different warm-up protocols and the effects of IME on 100 m freestyle swimming times were assessed.Each swimmer completed four different IME warm-up protocols across four separate study visits: swimming-only warm-up; swimming warm-up plus IME warm-up (2 sets of 30 breaths with a 40% maximum inspiratory mouth pressure load using the Powerbreathe inspiratory muscle trainer); swimming warm-up plus sham IME warm-up (2 sets of 30 breaths with a 15% maximum inspiratory mouth pressure load using the Powerbreathe inspiratory muscle trainer); and IME-only warm-up. Swimmers performed a series of physiological tests and scales of perception (rate of perceived exertion and dyspnoea) at three time points (pre warm-up, post warm-up and post time trial). The combined standard swimming warm-up and IME warm-up were the fastest of the four protocols with a 100 m time of 57.05 s. This was significantly faster than the IME-only warm-up (mean difference=1.18 s, 95% CI 0.44 to 1.92, p<0.01) and the swim-only warm-up (mean difference=0.62 s, 95% CI 0.001 to 1.23, p=0.05). Using IME combined with a standard swimming warm-up significantly improves 100 m freestyle swimming performance in elite swimmers.
Kung-fu versus swimming training and the effects on balance abilities in young adolescents.
Baccouch, Rym; Rebai, Haithem; Sahli, Sonia
2015-11-01
Our purpose is to investigate the static balance control of young adolescents practicing kung-fu and swimming in order to find out which of these physical activities is the most effective in developing specific balance abilities in young adolescents. Comparative experimental study. University laboratory research. Three groups of 11-13-year-old boys (12 practicing Kung-Fu, 12 practicing swimming and 12 controls). Center of pressure (CoP) excursions were registered in upright bipedal and unipedal stances on a stabilometric force platform in eyes open (EO) and eyes closed (EC) conditions. Kung-fu practitioners control their balance (P < .05) better than controls and swimmers in the unipedal posture when visual inputs are available. Kung-fu training improved (P < .05) the bipedal balance control in the EO condition. However, swimming training developed (P < .05) bipedal balance control in both EO and EC conditions. The swimmers showed a lower reliance on vision (P < .05) compared to kung-fu practitioners. Both of these physical activities could be recommended for young adolescents as recreational or rehabilitation programs as they develop specific balance abilities that could be important for improving and maintaining optimal health. Copyright © 2015 Elsevier Ltd. All rights reserved.
Locomotion of bacteria in liquid flow and the boundary layer effect on bacterial attachment
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang, Chao, E-mail: zhangchao@cqu.edu.cn; Institute of Engineering Thermophysics, Chongqing University, Chongqing 400030; Liao, Qiang, E-mail: lqzx@cqu.edu.cn
The formation of biofilm greatly affects the performance of biological reactors, which highly depends on bacterial swimming and attachment that usually takes place in liquid flow. Therefore, bacterial swimming and attachment on flat and circular surfaces with the consideration of flow was studied experimentally. Besides, a mathematical model comprehensively combining bacterial swimming and motion with flow is proposed for the simulation of bacterial locomotion and attachment in flow. Both experimental and theoretical results revealed that attached bacteria density increases with decreasing boundary layer thickness on both flat and circular surfaces, the consequence of which is inherently related to the competitionmore » between bacterial swimming and the non-slip motion with flow evaluated by the Péclet number. In the boundary layer, where the Péclet number is relatively higher, bacterial locomotion mainly depends on bacterial swimming. Thinner boundary layer promotes bacterial swimming towards the surface, leading to higher attachment density. To enhance the performance of biofilm reactors, it is effective to reduce the boundary layer thickness on desired surfaces. - Highlights: • Study of bacterial locomotion in flow as an early stage in biofilm formation. • Mathematical model combining bacterial swimming and the motion with flow. • Boundary layer plays a key role in bacterial attachment under flow condition. • The competition between bacterial swimming and the motion with flow is evaluated.« less
Simulations of dolphin kick swimming using smoothed particle hydrodynamics.
Cohen, Raymond C Z; Cleary, Paul W; Mason, Bruce R
2012-06-01
In competitive human swimming the submerged dolphin kick stroke (underwater undulatory swimming) is utilized after dives and turns. The optimal dolphin kick has a balance between minimizing drag and maximizing thrust while also minimizing the physical exertion required of the swimmer. In this study laser scans of athletes are used to provide realistic swimmer geometries in a single anatomical pose. These are rigged and animated to closely match side-on video footage. Smoothed Particle Hydrodynamics (SPH) fluid simulations are performed to evaluate variants of this swimming stroke technique. This computational approach provides full temporal and spatial information about the flow moving around the deforming swimmer model. The effects of changes in ankle flexibility and stroke frequency are investigated through a parametric study. The results suggest that the net streamwise force on the swimmer is relatively insensitive to ankle flexibility but is strongly dependent on kick frequency. Crown Copyright © 2011. Published by Elsevier B.V. All rights reserved.
Wearable inertial sensors in swimming motion analysis: a systematic review.
de Magalhaes, Fabricio Anicio; Vannozzi, Giuseppe; Gatta, Giorgio; Fantozzi, Silvia
2015-01-01
The use of contemporary technology is widely recognised as a key tool for enhancing competitive performance in swimming. Video analysis is traditionally used by coaches to acquire reliable biomechanical data about swimming performance; however, this approach requires a huge computational effort, thus introducing a delay in providing quantitative information. Inertial and magnetic sensors, including accelerometers, gyroscopes and magnetometers, have been recently introduced to assess the biomechanics of swimming performance. Research in this field has attracted a great deal of interest in the last decade due to the gradual improvement of the performance of sensors and the decreasing cost of miniaturised wearable devices. With the aim of describing the state of the art of current developments in this area, a systematic review of the existing methods was performed using the following databases: PubMed, ISI Web of Knowledge, IEEE Xplore, Google Scholar, Scopus and Science Direct. Twenty-seven articles published in indexed journals and conference proceedings, focusing on the biomechanical analysis of swimming by means of inertial sensors were reviewed. The articles were categorised according to sensor's specification, anatomical sites where the sensors were attached, experimental design and applications for the analysis of swimming performance. Results indicate that inertial sensors are reliable tools for swimming biomechanical analyses.
Hypothesised mechanisms of swimming-related death: a systematic review.
Asplund, Chad A; Creswell, Lawrence L
2016-11-01
Recent reports from triathlon and competitive open-water swimming indicate that these events have higher rates of death compared with other forms of endurance sport. The potential causal mechanism for swimming-related death is unclear. To examine available studies on the hypothesised mechanisms of swimming-related death to determine the most likely aetiologies. MEDLINE, EMBASE and the Cochrane Database of Systematic Reviews (1950 to present) were searched, yielding 1950 potential results, which after title and citation reviews were reduced to 83 possible reports. Studies included discussed mechanisms of death during swimming in humans, and were Level 4 evidence or higher. A total of 17 studies (366 total swimmers) were included for further analysis: 5 investigating hyperthermia/hypothermia, 7 examining cardiac mechanisms and responses, and 5 determining the presence of pulmonary edema. The studies provide inconsistent and limited-quality or disease-oriented evidence that make definitive conclusions difficult. The available evidence is limited but may suggest that cardiac arrhythmias are the most likely aetiology of swimming-related death. While symptoms of pulmonary edema may occur during swimming, current evidence does not support swimming-induced pulmonary edema as a frequent cause of swimming-related death, nor is there evidence to link hypothermia or hyperthermia as a causal mechanism. Further higher level studies are needed. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.
The relative age effect among elite youth competitive swimmers.
Costa, Aldo M; Marques, Mário C; Louro, Hugo; Ferreira, Sandra S; Marinho, Daniel A
2013-01-01
The aim of this study was to analyse the relative age effect (RAE) in competitive swimming. The best 50 Portuguese swimmers (12- to 18-year-olds) for the main individual swimming pool events of both genders were considered. Analysis was conducted on 7813 swimming event participants, taking account of respective swimmer birth dates and the Fédération Internationale de Natation points gained. Differences in the distribution of birth dates by quarter year were determined using the Chi-square. A one-way analysis of variance ANOVA was used to test for differences measured in points between individuals by quarterly birth year intervals. A two-way analysis of variance ANOVA was also conducted to test the interaction between gender and seasonal birth date with regard to performance. The results show an inequitable distribution (p<0.01) of birth dates by quarter for almost all age groups and both genders. However, the distribution of birth dates by quarter for each considered swim event shows that RAE seems to exist only for 12-year-old females and 12- to 15-year-old males. Analysing mean swimming performance, post-hoc results (p<0.01) show no consistency in RAE. Higher performance occurs among older swimmers only in 100 m butterfly (female 1998, 1st≠2nd quarter, p=0.003). The results also show no interaction between gender and seasonal birth date (p<0.01). Findings of this study show that a higher number of swimmers, particular males, are born in the first two quarters of the year, although there is mostly no effect of seasonal birth date on performance differences within the top 50 swimmers.
The effects of swimming and running on energy intake during 2 hours of recovery.
Lambert, C P; Flynn, M G; Braun, W A; Boardley, D J
1999-12-01
To determine energy intake in the 2 hrs after swimming (S) and running (R) at the same relative exercise intensity and duration (71.8 +/- 2.5% VO2max; 45 min) to evaluate whether a difference in recovery energy intake could explain the greater body fat observed in swimmers relative to runners. this was a randomized crossover design. running exercise was conducted on a motorized treadmill (Quinton) while swimming was conducted in a 45.7 m pool. eight well-trained competitive male triathletes participated in this investigation. subjects were blinded to the purpose of the study and swam and ran on separate occasions for 45 min at 71.8 +/- 2.5% of VO2max. Subjects were then placed in a room with a variety of foods and beverages for 2 hrs after R and S. energy intake (kJ/2 hrs and kcal/2 hrs) was determined by weighing and measuring the food remaining in the room after 2 hrs of postexercise recovery. Expired gases, heart rates, and Ratings of Perceived Exertion were obtained at 15 min intervals throughout exercise. Blood samples for serum glucose and lactate were obtained preexercise and immediately, 15 min, and 135 min postexercise. Perceived hunger and thirst ratings were obtained after the subjects were seated in the room containing the food. Serum glucose was significantly (p < or = 0.05) higher after R compared to S immediately after exercise (5.4 +/- 0.3 mmol/L for R and 4.2 +/- 0.1 mmol/L for S) but no significant differences were observed for hunger using a five point Likert scale (3.3 +/- 0.3 for R and 3.4 +/- 0.3 for S), energy intake (4584 +/- 611 kJ/2 hrs; 1095 +/- 146 kcal/2 hrs for R and 4383 +/- 484 kJ/2 hrs; 1047 +/- 116 kcal for S) or blood lactate. The type of exercise, swimming or running, did not significantly influence energy intake during 2 hours of postexercise recovery.
Prathima, S; Devi, S A
1999-04-01
The responses of the left and right ventricles (LV and RV) to physical conditioning in cold (25 degrees C) and thermoneutral temperatures (35 degrees C), with special reference to lactate dehydrogenase (LDH) and its isoenzyme profile, were studied in the 2-month (young)- and 12-month (middle-aged)-old rats. Moderate hypertrophy was a common observation irrespective of age, region and swim temperature. LV, however, hypertrophied to a significantly lesser extent in the middle-aged, than the RV. Blood Lactate (La) content showed a decline in the trained rather than their untrained counterparts. LDH activity decreased with age. Swim training induced elevations in the enzyme activity. The isoenzyme profile was suitably and efficiently altered in the LV and RV of trained animals to meet the arising O2 demands. The above adaptations were best seen in the young and in the animals trained at thermoneutral temperatures. Thus it is suggested that young age is very apt for initiation of training programs although middle-age is not so late. Swimming in water near body temperature is emphasised as a more preferred environment to cold water, in order to derive maximal exercise-associated beneficial effects.
Creatine supplementation and swim performance: a brief review.
Hopwood, Melissa J; Graham, Kenneth; Rooney, Kieron B
2006-03-01
Nutritional supplements are popular among athletes participating in a wide variety of sports. Creatine is one of the most commonly used dietary supplements, as it has been shown to be beneficial in improving performance during repeated bouts of high-intensity anaerobic activity. This review examines the specific effects of creatine supplementation on swimming performance, and considers the effects of creatine supplementation on various measures of power development in this population. Research performed on the effect of creatine supplementation on swimming performance indicates that whilst creatine supplementation is ineffective in improving performance during a single sprint swim, dietary creatine supplementation may benefit repeated interval swim set performance. Considering the relationship between sprint swimming performance and measurements of power, the effect of creatine supplementation on power development in swimmers has also been examined. When measured on a swim bench ergometer, power development does show some improvement following a creatine supplementation regime. How this improvement in power output transfers to performance in the pool is uncertain. Although some evidence exists to suggest a gender effect on the performance improvements seen in swimmers following creatine supplementation, the majority of research indicates that male and female swimmers respond equally to supplementation. A major limitation to previous research is the lack of consideration given to the possible stroke dependant effect of creatine supplementation on swimming performance. The majority of the research conducted to date has involved examination of the freestyle swimming stroke only. The potential for performance improvements in the breaststroke and butterfly swimming strokes is discussed, with regards to the biomechanical differences and differences in efficiency between these strokes and freestyle. Key PointsCreatine supplementation does not improve single sprint swimming performance.Creatine supplementation does improve repeated interval swim set performance.Creatine supplementation does improve power development in swimmers when measured on a swim bench ergometer.As a result of the high energy demands of the butterfly and breaststroke competitive swimming styles, potentially, the benefits associated with creatine supplementation and swimming performance could be greater when swimming butterfly or breaststroke, compared to the commonly examined freestyle swimming stroke.
Comparison between recreational male Ironman triathletes and marathon runners.
Gianoli, Daniele; Knechtle, Beat; Knechtle, Patrizia; Barandun, Ursula; Rüst, Christoph Alexander; Rosemann, Thomas
2012-08-01
Recent investigations described a personal best marathon time as a predictor variable for an Ironman race time in recreational male Ironman triathletes. Similarities and differences in anthropometry and training were investigated between 83 recreational male Ironman triathletes and 81 recreational male marathoners. Ironman triathletes were significantly taller and had a higher body mass and a higher skin-fold thickness of the calf compared to the marathoners. Weekly training volume in hours was higher in Ironman triathletes. In the Ironman triathletes, percent body fat was related to overall race time and both the split time in cycling and running. The weekly swim kilometres were related to the split time in swimming, and the speed in cycling was related to the bike split time. For the marathoners, the calf skin-fold thickness and running speed during training were related to marathon race time. Although personal best marathon time was a predictor of Ironman race time in male triathletes, anthropometric and training characteristics of male marathoners were different from those of male Ironman triathletes, probably due to training of different muscle groups and metabolic endurance beyond marathon running, as the triathletes are also training for high-level performance in swimming and cycling. Future studies should compare Olympic distance triathletes and road cyclists with Ironman triathletes.
Thrust and power measurements of Olympic swimmers
NASA Astrophysics Data System (ADS)
Wei, Timothy; Wu, Vicki; Hutchison, Sean; Mark, Russell
2012-11-01
Elite level swimming is an extremely precise and even choreographed activity. Swimmers not only know the exact number of strokes necessary to take them across the pool, they also plan to be a precise distance from the wall at the end of their last stroke. Too far away and they lose time by drifting into the wall. Too close and their competitor may slide in before their hand comes forward to touch the wall. In this context, it is important to know, in detail, where and how a swimmer propels her/himself through the water. Over the past decade, state-of-the-art flow and thrust measurement diagnostics have been brought to competitive swimming. But the ability to correlate stroke mechanics to thrust production without somehow constraining the swimmer has here-to-fore not been possible. Using high speed video, a simple approach to mapping the swimmer's speed, thrust and net power output in a time resolved manner has been developed. This methodology has been applied to Megan Jendrick, gold medalist in the 100 individual breast stroke and 4 × 100 medley relay events in 2000 and Ariana Kukors, 2009 world champion and continuing world record holder in the 200 individual medley. Implications for training future elite swimmers will be discussed.
Belke, Darrell D
2011-07-01
Swim-training exercise in mice leads to cardiac remodeling associated with an improvement in contractile function. Protein O-linked N-acetylglucosamine (O-GlcNAcylation) is a posttranslational modification of serine and threonine residues capable of altering protein-protein interactions affecting gene transcription, cell signaling pathways, and general cell physiology. Increased levels of protein O-GlcNAcylation in the heart have been associated with pathological conditions such as diabetes, ischemia, and hypertrophic heart failure. In contrast, the impact of physiological exercise on protein O-GlcNAcylation in the heart is currently unknown. Swim-training exercise in mice was associated with the development of a physiological hypertrophy characterized by an improvement in contractile function relative to sedentary mice. General protein O-GlcNAcylation was significantly decreased in swim-exercised mice. This effect was mirrored in the level of O-GlcNAcylation of individual proteins such as SP1. The decrease in protein O-GlcNAcylation was associated with a decrease in the expression of O-GlcNAc transferase (OGT) and glutamine-fructose amidotransferase (GFAT) 2 mRNA. O-GlcNAcase (OGA) activity was actually lower in swim-trained than sedentary hearts, suggesting that it did not contribute to the decreased protein O-GlcNAcylation. Thus it appears that exercise-induced physiological hypertrophy is associated with a decrease in protein O-GlcNAcylation, which could potentially contribute to changes in gene expression and other physiological changes associated with exercise.
Messinis, Spilios; Beidaris, Nikos; Messinis, Spyros; Soultanakis, Helen; Botonis, Petros; Platanou, Theodoros
2014-01-01
The use of swimming aids during training contributes to greater swimming efficiency by the improvement of the swimming specific power of the athlete. The purpose of this study was to compare the swimming stroke technical characteristics and the physiological responses of swimming 100-m backstroke, with and without the use of paddles at maximum and sub-maximum intensities at the same swimming speed. Eight swimmers competing at the national level participated in this study. The measurements took place at 4 different sessions. At every session, each participant swam individually one 100-m backstroke swimming trial with or without paddles at the same speed and two levels of intensity (100% and 85% of maximum speed). The results revealed lower stroke length, greater stroke number and gliding length without the use of swimming paddles at both intensities. Blood lactate concentration (10.03±2.96 vs. 5.85±2.23 mmol/l) and Rating of Perceived Exertion (17.43±2.07 vs. 12±2.82) were greater without the use of swimming paddles only at 100% of maximum speed. Thus, swimming backstroke with paddles compared to unaided swimming, at a similar speed, showed a greater efficiency at maximal but not at sub-maximal intensity. PMID:25031685
Messinis, Spilios; Beidaris, Nikos; Messinis, Spyros; Soultanakis, Helen; Botonis, Petros; Platanou, Theodoros
2014-03-27
The use of swimming aids during training contributes to greater swimming efficiency by the improvement of the swimming specific power of the athlete. The purpose of this study was to compare the swimming stroke technical characteristics and the physiological responses of swimming 100-m backstroke, with and without the use of paddles at maximum and sub-maximum intensities at the same swimming speed. Eight swimmers competing at the national level participated in this study. The measurements took place at 4 different sessions. At every session, each participant swam individually one 100-m backstroke swimming trial with or without paddles at the same speed and two levels of intensity (100% and 85% of maximum speed). The results revealed lower stroke length, greater stroke number and gliding length without the use of swimming paddles at both intensities. Blood lactate concentration (10.03±2.96 vs. 5.85±2.23 mmol/l) and Rating of Perceived Exertion (17.43±2.07 vs. 12±2.82) were greater without the use of swimming paddles only at 100% of maximum speed. Thus, swimming backstroke with paddles compared to unaided swimming, at a similar speed, showed a greater efficiency at maximal but not at sub-maximal intensity.
Numerical and experimental investigations of human swimming motions
Takagi, Hideki; Nakashima, Motomu; Sato, Yohei; Matsuuchi, Kazuo; Sanders, Ross H.
2016-01-01
ABSTRACT This paper reviews unsteady flow conditions in human swimming and identifies the limitations and future potential of the current methods of analysing unsteady flow. The capability of computational fluid dynamics (CFD) has been extended from approaches assuming steady-state conditions to consideration of unsteady/transient conditions associated with the body motion of a swimmer. However, to predict hydrodynamic forces and the swimmer’s potential speeds accurately, more robust and efficient numerical methods are necessary, coupled with validation procedures, requiring detailed experimental data reflecting local flow. Experimental data obtained by particle image velocimetry (PIV) in this area are limited, because at present observations are restricted to a two-dimensional 1.0 m2 area, though this could be improved if the output range of the associated laser sheet increased. Simulations of human swimming are expected to improve competitive swimming, and our review has identified two important advances relating to understanding the flow conditions affecting performance in front crawl swimming: one is a mechanism for generating unsteady fluid forces, and the other is a theory relating to increased speed and efficiency. PMID:26699925
Fernández-Luna, Álvaro; Burillo, Pablo; Felipe, José Luis; del Corral, Julio; García-Unanue, Jorge; Gallardo, Leonor
2016-01-01
The objective of this study was to determine which chemical treatment used for disinfecting water in indoor swimming pools had the least impact on users' perceptions of health problems, and which generated the greatest satisfaction with the quality of the water. A survey on satisfaction and perceived health problems was given to 1001 users at 20 indoor swimming pools which used different water treatment methods [chlorine, bromine, ozone, ultraviolet lamps (UV) and salt electrolysis]. The findings suggest that there is a greater probability of perceived health problems, such as eye and skin irritation, respiratory problems and skin dryness, in swimming pools treated with chlorine than in swimming pools using other chemical treatment methods. Pools treated with bromine have similar, although slightly better, results. Other factors, such as age, gender, time of day of use (morning and afternoon) and type of user (competitive and recreational), can also affect the probability of suffering health problems. For all of the above, using combined treatment methods as ozone and UV, or salt electrolysis produces a lower probability of perceived health problems and greater satisfaction.
Numerical and experimental investigations of human swimming motions.
Takagi, Hideki; Nakashima, Motomu; Sato, Yohei; Matsuuchi, Kazuo; Sanders, Ross H
2016-08-01
This paper reviews unsteady flow conditions in human swimming and identifies the limitations and future potential of the current methods of analysing unsteady flow. The capability of computational fluid dynamics (CFD) has been extended from approaches assuming steady-state conditions to consideration of unsteady/transient conditions associated with the body motion of a swimmer. However, to predict hydrodynamic forces and the swimmer's potential speeds accurately, more robust and efficient numerical methods are necessary, coupled with validation procedures, requiring detailed experimental data reflecting local flow. Experimental data obtained by particle image velocimetry (PIV) in this area are limited, because at present observations are restricted to a two-dimensional 1.0 m(2) area, though this could be improved if the output range of the associated laser sheet increased. Simulations of human swimming are expected to improve competitive swimming, and our review has identified two important advances relating to understanding the flow conditions affecting performance in front crawl swimming: one is a mechanism for generating unsteady fluid forces, and the other is a theory relating to increased speed and efficiency.
[Dynamics of oxygen uptake during a 100 m front crawl event, performed during competition ].
Jalab, Chadi; Enea, Carina; Delpech, Nathalie; Bernard, Olivier
2011-04-01
The main purpose of this study is to estimate the dynamics of oxygen uptake (VO2) during a 100 m front crawl event, performed in competition conditions. Eleven trained swimmers participated in 2 separate sessions, in a 25 m swimming pool. Maximal oxygen uptake (VO2max) was determined during a 400 m maximal event. Swimmers also performed a 100 m front crawl in competition conditions, and then, 3 tests (25, 50, and 75 m) following the pacing strategy of the 100 m event. To be free of technical constraints, VO2 was not measured during the tests, but before and just at the end of each test with a 1 min breath-by-breath method. Each post-test VO2 measurement (after 25, 50, 75, and 100 m) allows us to reconstruct the VO2 kinetics of the 100 m performance. Our results differ from previous studies in that VO2 increases faster in the first half of the race (at 50 m, VO2 ≈ 94% VO2max), reaches VO2max at the 75 m mark; then a decrease in VO2 corresponding to 7% of VO2max appears during the last 25 m. These differences are supposed to be mainly the consequences of the adoption of technical elements and a pacing strategy similar to competition conditions. In the future, these observations may lead to different considerations of the bioenergetic contributions.
Acute consumption of a caffeinated energy drink enhances aspects of performance in sprint swimmers.
Lara, Beatriz; Ruiz-Vicente, Diana; Areces, Francisco; Abián-Vicén, Javier; Salinero, Juan José; Gonzalez-Millán, Cristina; Gallo-Salazar, César; Del Coso, Juan
2015-09-28
This study investigated the effect of a caffeinated energy drink on various aspects of performance in sprint swimmers. In a randomised and counterbalanced order, fourteen male sprint swimmers performed two acute experimental trials after the ingestion of a caffeinated energy drink (3 mg/kg) or after the ingestion of the same energy drink without caffeine (0 mg/kg; placebo). After 60 min of ingestion of the beverages, the swimmers performed a countermovement jump, a maximal handgrip test, a 50 m simulated competition and a 45 s swim at maximal intensity in a swim ergometer. A blood sample was withdrawn 1 min after the completion of the ergometer test. In comparison with the placebo drink, the intake of the caffeinated energy drink increased the height in the countermovement jump (49.4 (SD 5.3) v. 50.9 (SD 5.2) cm, respectively; P<0.05) and maximal force during the handgrip test with the right hand (481 (SD 49) v. 498 (SD 43) N; P<0.05). Furthermore, the caffeinated energy drink reduced the time needed to complete the 50 m simulated swimming competition (27.8 (SD 3.4) v. 27.5 (SD 3.2) s; P<0.05), and it increased peak power (273 (SD 55) v. 303 (SD 49) W; P <0.05) and blood lactate concentration (11.0 (SD 2.0) v. 11.7 (SD 2.1) mM; P<0.05) during the ergometer test. The caffeinated energy drink did not modify the prevalence of insomnia (7 v. 7%), muscle pain (36 v. 36%) or headache (0 v. 7%) during the hours following its ingestion (P>0.05). A caffeinated energy drink increased some aspects of swimming performance in competitive sprinters, whereas the side effects derived from the intake of this beverage were marginal at this dosage.
Waterfront Certification Changes.
ERIC Educational Resources Information Center
O'Brien, Laurie
1995-01-01
Overviews certification changes affecting lifeguard training, progressive swimming instructors, CPR and first aid training, canoeing and kayaking instructors, sailing instructors, water skiing instructors, and instructor trainers. Addresses how changes impact American Camping Association standards. Provides addresses of training organizations. (LP)
London 2012 Paralympic swimming: passive drag and the classification system.
Oh, Yim-Taek; Burkett, Brendan; Osborough, Conor; Formosa, Danielle; Payton, Carl
2013-09-01
The key difference between the Olympic and Paralympic Games is the use of classification systems within Paralympic sports to provide a fair competition for athletes with a range of physical disabilities. In 2009, the International Paralympic Committee mandated the development of new, evidence-based classification systems. This study aims to assess objectively the swimming classification system by determining the relationship between passive drag and level of swimming-specific impairment, as defined by the current swimming class. Data were collected on participants at the London 2012 Paralympic Games. The passive drag force of 113 swimmers (classes 3-14) was measured using an electro-mechanical towing device and load cell. Swimmers were towed on the surface of a swimming pool at 1.5 m/s while holding their most streamlined position. Passive drag ranged from 24.9 to 82.8 N; the normalised drag (drag/mass) ranged from 0.45 to 1.86 N/kg. Significant negative associations were found between drag and the swimming class (τ = -0.41, p < 0.01) and normalised drag and the swimming class (τ = -0.60, p < 0.01). The mean difference in drag between adjacent classes was inconsistent, ranging from 0 N (6 vs 7) to 11.9 N (5 vs 6). Reciprocal Ponderal Index (a measure of slenderness) correlated moderately with normalised drag (r(P) = -0.40, p < 0.01). Although swimmers with the lowest swimming class experienced the highest passive drag and vice versa, the inconsistent difference in mean passive drag between adjacent classes indicates that the current classification system does not always differentiate clearly between swimming groups.
Swimming Pools. Managing School Facilities, Guide 2.
ERIC Educational Resources Information Center
Department for Education and Employment, London (England). Architects and Building Branch.
This guide for schools with swimming pools offers advice concerning appropriate training for pool managers, the importance of water quality and testing, safety in the handling of chemicals, maintenance and cleaning requirements, pool security, and health concerns. The guide covers both indoor and outdoor pools, explains some technical terms,…
A Practical Guide for Teaching the Mentally Retarded to Swim.
ERIC Educational Resources Information Center
American Association for Health, Physical Education, and Recreation, Washington, DC.
A guide for teaching the retarded to swim begins with a general discussion of retardation, the need for individualization, and staff qualifications. Factors discussed in program organization and administration include community agencies, staff training, examples of records and forms, and first aid procedures. Suggested methods consider perceptual…
Bielec, G.; Makar, P.; Laskowski, R.
2013-01-01
Short duration repeated maximal efforts are often used in swimming training to improve lactate tolerance, which gives swimmers the ability to maintain a high work rate for a longer period of time. The aim of the study was to examine the kinematics of swimming and its relation to the changes in blood acid-base status and potassium level. Seven collegiate swimmers, with at least 6 years of training experience, volunteered to participate in the study. The test consisted of 8 x 25 m front crawl performed with maximum effort. The rest period between repetitions was set to five seconds. Blood samples were taken from the fingertip at rest, after warm-up and in the 3rd minute after completion of the test. The swimming was recorded with a video recorder, for later analysis of time, velocity and technique (stroke index). Based on the swimming velocity results, the obtained curve can be divided into rapid decrease of velocity and relatively stable velocities. The breaking point of repetition in swimming velocity was assumed as the swimming velocity threshold and it was highly correlated with the decrease of the blood acid-base status (pH r=0.82, BE r=0.87, HCO3 - r=0.76; p<0.05 in all cases). There was no correlation between stroke index or fatigue index and blood acid-base status. Analysis of the swimming speed in the 8 x 25 m test seems to be helpful in evaluation of lactate tolerance (anaerobic capacity) in collegiate swimmers. PMID:24744491
Ramos Veliz, Rafael; Requena, Bernardo; Suarez-Arrones, Luis; Newton, Robert U; Sáez de Villarreal, Eduardo
2014-04-01
We examined the effects of 18 weeks of strength and high-intensity training on key sport performance measures of elite male water polo (WP) players. Twenty-seven players were randomly assigned to 2 groups, control (in-water training only) and strength group, (strength training sessions [twice per week] + in-water training). In-water training was conducted 5 d·wk. Twenty-meter maximal sprint swim, maximal dynamic strength 1-repetition maximum (1RM) for upper bench press (BP) and lower full squat (FS) body, countermovement jump (CMJ), and throwing velocity were measured before and after the training. The training program included upper and lower body strength and high-intensity exercises (BP, FS, military press, pull-ups, CMJ loaded, and abs). Baseline-training results showed no significant differences between the groups in any of the variables tested. No improvement was found in the control group; however, meaningful improvement was found in all variables in the experimental group: CMJ (2.38 cm, 6.9%, effect size [ES] = 0.48), BP (9.06 kg, 10.53%, ES = 0.66), FS (11.06 kg, 14.21%, ES = 0.67), throwing velocity (1.76 km·h(-1), 2.76%, ES = 0.25), and 20-m maximal sprint swim (-0.26 seconds, 2.25%, ES = 0.29). Specific strength and high-intensity training in male WP players for 18 weeks produced a positive effect on performance qualities highly specific to WP. Therefore, we propose modifications to the current training methodology for WP players to include strength and high-intensity training for athlete preparation in this sport.
Wasinski, Frederick; Estrela, Gabriel R.; Arakaki, Aline M.; Bader, Michael; Alenina, Natalia; Klempin, Friederike; Araújo, Ronaldo C.
2016-01-01
Physical exercise positively affects the metabolism and induces proliferation of precursor cells in the adult brain. Maternal exercise likewise provokes adaptations early in the offspring. Using a high-intensity swimming protocol that comprises forced swim training before and during pregnancy, we determined the effect of maternal swimming on the mouse offspring's neurogenesis. Our data demonstrate decreased proliferation in sublayers of the postnatal dentate gyrus in offspring of swimming mother at postnatal day (P) 8 accompanied with decreased survival of newly generated cells 4 weeks later. The reduction in cell numbers was predominantly seen in the hilus and molecular layer. At P35, the reduced amount of cells was also reflected by a decrease in the population of newly generated immature and mature neurons of the granule cell layer. Our data suggest that forced maternal swimming at high-intensity has a negative effect on the neurogenic niche development in postnatal offspring. PMID:27621701
Sousa, Ana C.; Vilas-Boas, João P.; Fernandes, Ricardo J.
2014-01-01
A bioenergetical analysis of swimming at intensities near competitive distances is inexistent. It was aimed to compare the transient VO2 kinetics responses and metabolic contributions whilst swimming at different velocities around VO2max. 12 trained male swimmers performed (i) an incremental protocol to determine the velocity at VO2max (vVO2max) and (ii) three square wave exercises from rest to 95, 100, and 105% of vVO2max. VO2 was directly measured using a telemetric portable gas analyser and its kinetics analysed through a double-exponential model. Metabolic contributions were assessed through the sum of three energy components. No differences were observed in the fast component response (τ 1—15, 18, and 16 s, A 1—36, 34, and 37 mL · kg−1 · min−1, and Gain—32, 29, and 30 mL · min−1 at 95, 100, and 105% of the vVO2max, resp.) but A2 was higher in 95 and 100% compared to 105% intensity (480.76 ± 247.01, 452.18 ± 217.04, and 147.04 ± 60.40 mL · min−1, resp.). The aerobic energy contribution increased with the time sustained (83 ± 5, 74 ± 6, and 59 ± 7% for 95, 100, and 105%, resp.). The adjustment of the cardiovascular and/or pulmonary systems that determine O2 delivery and diffusion to the exercising muscles did not change with changing intensity, with the exception of VO2 slow component kinetics metabolic profiles. PMID:25045690
All-automatic swimmer tracking system based on an optimized scaled composite JTC technique
NASA Astrophysics Data System (ADS)
Benarab, D.; Napoléon, T.; Alfalou, A.; Verney, A.; Hellard, P.
2016-04-01
In this paper, an all-automatic optimized JTC based swimmer tracking system is proposed and evaluated on real video database outcome from national and international swimming competitions (French National Championship, Limoges 2015, FINA World Championships, Barcelona 2013 and Kazan 2015). First, we proposed to calibrate the swimming pool using the DLT algorithm (Direct Linear Transformation). DLT calculates the homography matrix given a sufficient set of correspondence points between pixels and metric coordinates: i.e. DLT takes into account the dimensions of the swimming pool and the type of the swim. Once the swimming pool is calibrated, we extract the lane. Then we apply a motion detection approach to detect globally the swimmer in this lane. Next, we apply our optimized Scaled Composite JTC which consists of creating an adapted input plane that contains the predicted region and the head reference image. This latter is generated using a composite filter of fin images chosen from the database. The dimension of this reference will be scaled according to the ratio between the head's dimension and the width of the swimming lane. Finally, applying the proposed approach improves the performances of our previous tracking method by adding a detection module in order to achieve an all-automatic swimmer tracking system.
Core strengthening and synchronized swimming: TRX® suspension training in young female athletes.
Tinto, Amalia; Campanella, Marta; Fasano, Milena
2017-06-01
Developing muscle strength and full body stability is essential for the efficient execution of technical moves in synchronized swimming. However, many swimmers find it difficult to control body stability while executing particular figures in water. We evaluated the effects of TRX® suspension training (2 sessions weekly for 6 months on core strength and core stability in young female. Twenty synchronized swimmers (Beginners A category, mean age 10±1 years) are divided in experimental group (EG; N.=10 athletes) and control group (CG; N.=10 athletes). EG received suspension training twice weekly (each session lasting about 15 min) as dryland exercises for 6 months in addition to routine training. CG completed routine training with conventional dryland exercises. Before (T1) and after (T2) completion of the study oblique and transversus abdominis muscle force was measured using a Stabilizer Pressure Biofeedback unit, in prone and supine positions, and isotonic muscle endurance was evaluated with the McGill Test. Non-parametric statistical analysis showed a significant increase (P<0.0001) in the majority of the parameters in the experimental group. The study results provide evidence for the benefit of integrating TRX® suspension training in dryland exercises for muscle strengthening in young athletes practicing synchronized swimming, and in general reiterates the importance of strengthening the core area to ensure stability and specific adaptations, improve the quality of the movement and prevent against injury.
Chen, Yi-Ming; Lin, Che-Li; Wei, Li; Hsu, Yi-Ju; Chen, Kuan-Neng; Huang, Chi-Chang; Kao, Chin-Hsung
2016-01-01
Exercise and fitness training programs have attracted the public’s attention in recent years. Sports nutrition supplementation is an important issue in the global sports market. Purpose: In this study, we designed a power exercise training (PET) program with a mouse model based on a strength and conditional training protocol for humans. We tested the effect of supplementation with functional branched-chain amino acid (BCAA)-rich sake protein (SP) to determine whether the supplement had a synergistic effect during PET and enhanced athletic performance and resistance to fatigue. Methods: Male ICR mice were divided into three groups (n = 8 per group) for four-week treatment: sedentary controls with vehicle (SC), and PET and PET groups with SP supplementation (3.8 g/kg, PET + SP). Exercise performance was evaluated by forelimb grip strength and exhaustive swimming time as well as changes in body composition and anti-fatigue activity levels of serum lactate, ammonia, glucose, and creatine kinase (CK) after a 15-min swimming exercise. The biochemical parameters were measured at the end of the experiment. Results: four-week PET significantly increased grip strength and exhaustive swimming time and decreased epididymal fat pad (EFP) weight and area. Levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatinine, and uric acid (UA) were significantly increased. PET + SP supplementation significantly decreased serum lactate, ammonia and CK levels after the 15-min swimming exercise. The resting serum levels of AST, ALT, CREA and UA were all significantly decreased with PET + SP. Conclusion: The PET program could increase the exercise performance and modulate the body composition of mice. PET with SP conferred better anti-fatigue activity, improved biochemical profiles, and may be an effective ergogenic aid in strength training. PMID:26907336
Chen, Yi-Ming; Lin, Che-Li; Wei, Li; Hsu, Yi-Ju; Chen, Kuan-Neng; Huang, Chi-Chang; Kao, Chin-Hsung
2016-02-20
Exercise and fitness training programs have attracted the public's attention in recent years. Sports nutrition supplementation is an important issue in the global sports market. In this study, we designed a power exercise training (PET) program with a mouse model based on a strength and conditional training protocol for humans. We tested the effect of supplementation with functional branched-chain amino acid (BCAA)-rich sake protein (SP) to determine whether the supplement had a synergistic effect during PET and enhanced athletic performance and resistance to fatigue. Male ICR mice were divided into three groups (n = 8 per group) for four-week treatment: sedentary controls with vehicle (SC), and PET and PET groups with SP supplementation (3.8 g/kg, PET + SP). Exercise performance was evaluated by forelimb grip strength and exhaustive swimming time as well as changes in body composition and anti-fatigue activity levels of serum lactate, ammonia, glucose, and creatine kinase (CK) after a 15-min swimming exercise. The biochemical parameters were measured at the end of the experiment. four-week PET significantly increased grip strength and exhaustive swimming time and decreased epididymal fat pad (EFP) weight and area. Levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatinine, and uric acid (UA) were significantly increased. PET + SP supplementation significantly decreased serum lactate, ammonia and CK levels after the 15-min swimming exercise. The resting serum levels of AST, ALT, CREA and UA were all significantly decreased with PET + SP. The PET program could increase the exercise performance and modulate the body composition of mice. PET with SP conferred better anti-fatigue activity, improved biochemical profiles, and may be an effective ergogenic aid in strength training.
Varea-Sánchez, María; Gómez Montoto, Laura; Tourmente, Maximiliano; Roldan, Eduardo R. S.
2014-01-01
Interspecific comparative studies have shown that, in most taxa, postcopulatory sexual selection (PCSS) in the form of sperm competition drives the evolution of longer and faster swimming sperm. Work on passserine birds has revealed that PCSS also reduces variation in sperm size between males at the intraspecific level. However, the influence of PCSS upon intra-male sperm size diversity is poorly understood, since the few studies carried out to date in birds have yielded contradictory results. In mammals, PCSS increases sperm size but there is little information on the effects of this selective force on variations in sperm size and shape. Here, we test whether sperm competition associates with a reduction in the degree of variation of sperm dimensions in rodents. We found that as sperm competition levels increase males produce sperm that are more similar in both the size of the head and the size of the flagellum. On the other hand, whereas with increasing levels of sperm competition there is less variation in head length in relation to head width (ratio CV head length/CV head width), there is no relation between variation in head and flagellum sizes (ratio CV head length/CV flagellum length). Thus, it appears that, in addition to a selection for longer sperm, sperm competition may select more uniform sperm heads and flagella, which together may enhance swimming velocity. Overall, sperm competition seems to drive sperm components towards an optimum design that may affect sperm performance which, in turn, will be crucial for successful fertilization. PMID:25243923
Nutrition considerations in special environments for aquatic sports.
Stellingwerff, Trent; Pyne, David B; Burke, Louise M
2014-08-01
Elite athletes who compete in aquatic sports face the constant challenge of arduous training and competition schedules in difficult and changing environmental conditions. The huge range of water temperatures to which swimmers and other aquatic athletes are often exposed (16-31 °C for open-water swimming), coupled with altered aquatic thermoregulatory responses as compared with terrestrial athletes, can challenge the health, safety, and performance of these athletes. Other environmental concerns include air and water pollution, altitude, and jetlag and travel fatigue. However, these challenging environments provide the potential for several nutritional interventions that can mitigate the negative effects and enhance adaptation and performance. These interventions include providing adequate hydration and carbohydrate and iron intake while at altitude; optimizing body composition and fluid and carbohydrate intake when training or competing in varying water temperatures; and maximizing fluid and food hygiene when traveling. There is also emerging information on nutritional interventions to manage jetlag and travel fatigue, such as the timing of food intake and the strategic use of caffeine or melatonin. Aquatic athletes often undertake their major global competitions where accommodations feature cafeteria-style buffet eating. These environments can often lead to inappropriate choices in the type and quantity of food intake, which is of particular concern to divers and synchronized swimmers who compete in physique-specific sports, as well as swimmers who have a vastly reduced energy expenditure during their taper. Taken together, planned nutrition and hydration interventions can have a favorable impact on aquatic athletes facing varying environmental challenges.
Effects of endurance training in the leopard shark, Triakis semifasciata.
Gruber, S J; Dickson, K A
1997-01-01
This study is the first to examine the effects of endurance training in an elasmobranch fish. Twenty-four leopard sharks (Triakis semifasciata) were divided randomly into three groups. Eight sharks were killed immediately, eight were forced to swim continuously for 6 wk against a current of 35 cm s-1 (60%-65% of maximal sustainable swimming speed), and eight were held for 6 wk in a tank without induced current. There were no changes due to training in maximal sustainable speed, oxygen consumption rates, percentage of the myotome composed of red and white muscle fibers, blood oxygen-carrying capacity, liver mass, liver lipid, glycogen, and protein concentrations, white muscle protein content, heart ventricle mass, or the specific activities of the enzymes citrate synthase, pyruvate kinase, and lactate dehydrogenase in the heart ventricle. In red myotomal muscle, citrate synthase activity increased 17% as a result of training, but there was no change in muscle fiber diameter. The greatest effects occurred in white myotomal muscle, in which a 34% increase in fiber diameter and a 36% increase in the activities of citrate synthase and lactate dehydrogenase occurred as a result of training. The conditioned fish also had significantly higher growth rates. The observed effects within the myotomal muscle may reflect the higher growth rates of the trained leopard sharks, or they may be a specific response to the increased energetic demands of the training activity, indicating characteristics that limit swimming performance in leopard sharks.
Kanehisa, H; Muraoka, Y; Kawakami, Y; Fukunaga, T
2003-02-01
The thickness, fascicle angles of pennation, and fascicle length of the vastus lateralis (VL) and medial gastrocnemius (MG) muscles in highly trained soccer players and swimmers of both genders were determined from ulrasonograms to investigate whether the fascicle arrangements of the lower limb muscles in the athletes could be related to the requirements of the events, i. e., intensive muscular activities in the water versus on the ground. In comparisons between the two events, the soccer players tended to show shorter fascicles and greater fascicle angles, and the swimmers thicker muscles and longer fascicles, especially in VL. In both events, the males showed thicker muscles and greater fascicle angles than the females. In both VL and MG, the thickness, fascicle length and fascicle angle were related to each other in a right-angled triangle model, and so, most of the event- and/or gender-related differences observed in the fascicle angle depended on the difference in muscle thickness relative to fascicle length. The present data cannot answer the question of whether the athletes had muscles suited to their respective sports prior to beginning their sports or whether the muscles adapted specifically to the competitive and/or training styles. However, it might be assumed that the lower limb muscles for swimmers are suitable to perform rapid, powerful kick movements during competitive swims by having greater thickness and longer fascicle, i. e., priorities in both force production and shortening velocity, but those for soccer players do not show architectural profiles which can be related to intensive activity on the ground, except that the thickness values exceed the normal range.
de Koning, Jos J; Foster, Carl; Lucia, Alejandro; Bobbert, Maarten F; Hettinga, Florentina J; Porcari, John P
2011-06-01
Every new competitive season offers excellent examples of human locomotor abilities, regardless of the sport. As a natural consequence of competitions, world records are broken every now and then. World record races not only offer spectators the pleasure of watching very talented and highly trained athletes performing muscular tasks with remarkable skill, but also represent natural models of the ultimate expression of human integrated muscle biology, through strength, speed, or endurance performances. Given that humans may be approaching our species limit for muscular power output, interest in how athletes improve on world records has led to interest in the strategy of how limited energetic resources are best expended over a race. World record performances may also shed light on how athletes in different events solve exactly the same problem-minimizing the time required to reach the finish line. We have previously applied mathematical modeling to the understanding of world record performances in terms of improvements in facilities/equipment and improvements in the athletes' physical capacities. In this commentary, we attempt to demonstrate that differences in world record performances in various sports can be explained using a very simple modeling process.
Harder-Lauridsen, Nina Majlund; Kuhn, Katrin Gaardbo; Erichsen, Anders Christian; Mølbak, Kåre; Ethelberg, Steen
2013-01-01
Recent years have seen an increase in the frequency of extreme rainfall and subsequent flooding across the world. Climate change models predict that such flooding will become more common, triggering sewer overflows, potentially with increased risks to human health. In August 2010, a triathlon sports competition was held in Copenhagen, Denmark, shortly after an extreme rainfall. The authors took advantage of this event to investigate disease risks in two comparable cohorts of physically fit, long distance swimmers competing in the sea next to a large urban area. An established model of bacterial concentration in the water was used to examine the level of pollution in a spatio-temporal manner. Symptoms and exposures among athletes were examined with a questionnaire using a retrospective cohort design and the questionnaire investigation was repeated after a triathlon competition held in non-polluted seawater in 2011. Diagnostic information was collected from microbiological laboratories. The results showed that the 3.8 kilometer open water swimming competition coincided with the peak of post-flooding bacterial contamination in 2010, with average concentrations of 1.5x10(4) E. coli per 100 ml water. The attack rate of disease among 838 swimmers in 2010 was 42% compared to 8% among 931 swimmers in the 2011 competition (relative risk (RR) 5.0; 95% CI: 4.0-6.39). In 2010, illness was associated with having unintentionally swallowed contaminated water (RR 2.5; 95% CI: 1.8-3.4); and the risk increased with the number of mouthfuls of water swallowed. Confirmed aetiologies of infection included Campylobacter, Giardia lamblia and diarrhoeagenic E. coli. The study demonstrated a considerable risk of illness from water intake when swimming in contaminated seawater in 2010, and a small but measureable risk from non-polluted water in 2011. This suggests a significant risk of disease in people ingesting small amounts of flood water following extreme rainfall in urban areas.
Harder-Lauridsen, Nina Majlund; Kuhn, Katrin Gaardbo; Erichsen, Anders Christian; Mølbak, Kåre; Ethelberg, Steen
2013-01-01
Recent years have seen an increase in the frequency of extreme rainfall and subsequent flooding across the world. Climate change models predict that such flooding will become more common, triggering sewer overflows, potentially with increased risks to human health. In August 2010, a triathlon sports competition was held in Copenhagen, Denmark, shortly after an extreme rainfall. The authors took advantage of this event to investigate disease risks in two comparable cohorts of physically fit, long distance swimmers competing in the sea next to a large urban area. An established model of bacterial concentration in the water was used to examine the level of pollution in a spatio-temporal manner. Symptoms and exposures among athletes were examined with a questionnaire using a retrospective cohort design and the questionnaire investigation was repeated after a triathlon competition held in non-polluted seawater in 2011. Diagnostic information was collected from microbiological laboratories. The results showed that the 3.8 kilometer open water swimming competition coincided with the peak of post-flooding bacterial contamination in 2010, with average concentrations of 1.5x104 E. coli per 100 ml water. The attack rate of disease among 838 swimmers in 2010 was 42% compared to 8% among 931 swimmers in the 2011 competition (relative risk (RR) 5.0; 95% CI: 4.0-6.39). In 2010, illness was associated with having unintentionally swallowed contaminated water (RR 2.5; 95% CI: 1.8-3.4); and the risk increased with the number of mouthfuls of water swallowed. Confirmed aetiologies of infection included Campylobacter, Giardia lamblia and diarrhoeagenic E. coli. The study demonstrated a considerable risk of illness from water intake when swimming in contaminated seawater in 2010, and a small but measureable risk from non-polluted water in 2011. This suggests a significant risk of disease in people ingesting small amounts of flood water following extreme rainfall in urban areas. PMID:24244306
Plaza-Díaz, Julio; Ruiz-Ojeda, Francisco J.; Aragón-Vela, Jerónimo; Robles-Sanchez, Cándido; Nordsborg, Nikolai B.; Hebberecht, Marina; Salmeron, Luis M.; Huertas, Jesus R.
2017-01-01
We aimed to test whether high-intensity high-volume training (HIHVT) swimming would induce more robust signaling than sprint interval training (SIT) swimming within the m. triceps brachii due to lower metabolic and oxidation. Nine well-trained swimmers performed the two training procedures on separate randomized days. Muscle biopsies from m. triceps brachii and blood samples were collected at three different time points: a) before the intervention (pre), b) immediately after the swimming procedures (post) and c) after 3 h of rest (3 h). Hydroperoxides, creatine kinase (CK), and lactate dehydrogenase (LDH) were quantified from blood samples, and peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) and the AMPKpTHR172/AMPK ratio were quantified by Western blot analysis. PGC-1α, sirtuin 3 (SIRT3), superoxide-dismutase 2 (SOD2), and vascular endothelial growth factor (VEGF) mRNA levels were also quantified. SIT induced a higher release of LDH (p < 0.01 at all time points) and CK (p < 0.01 at post) than HIHVT, but neither SIT nor HIHVT altered systemic hydroperoxides. Additionally, neither SIRT3 nor SOD2 mRNA levels increased, while PGC-1α transcription increased at 3 h after SIT (p < 0.01) and after HIHVT (p < 0.001). However, PGC-1α protein was higher after HIHVT than after SIT (p < 0.05). Moreover, the AMPKpTHR172/AMPK ratio increased at post after SIT (p < 0.05), whereas this effect was delayed after HIHVT as it increased after 3 h (p < 0.05). In addition, VEGF transcription was higher in response to HIHVT (p < 0.05). In conclusion, SIT induces higher muscular stress than HIHVT without increasing systemic oxidation. In addition, HIHVT may induce more robust oxidative adaptations through PGC-1α and AMPK. PMID:28973039
Casuso, Rafael A; Plaza-Díaz, Julio; Ruiz-Ojeda, Francisco J; Aragón-Vela, Jerónimo; Robles-Sanchez, Cándido; Nordsborg, Nikolai B; Hebberecht, Marina; Salmeron, Luis M; Huertas, Jesus R
2017-01-01
We aimed to test whether high-intensity high-volume training (HIHVT) swimming would induce more robust signaling than sprint interval training (SIT) swimming within the m. triceps brachii due to lower metabolic and oxidation. Nine well-trained swimmers performed the two training procedures on separate randomized days. Muscle biopsies from m. triceps brachii and blood samples were collected at three different time points: a) before the intervention (pre), b) immediately after the swimming procedures (post) and c) after 3 h of rest (3 h). Hydroperoxides, creatine kinase (CK), and lactate dehydrogenase (LDH) were quantified from blood samples, and peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) and the AMPKpTHR172/AMPK ratio were quantified by Western blot analysis. PGC-1α, sirtuin 3 (SIRT3), superoxide-dismutase 2 (SOD2), and vascular endothelial growth factor (VEGF) mRNA levels were also quantified. SIT induced a higher release of LDH (p < 0.01 at all time points) and CK (p < 0.01 at post) than HIHVT, but neither SIT nor HIHVT altered systemic hydroperoxides. Additionally, neither SIRT3 nor SOD2 mRNA levels increased, while PGC-1α transcription increased at 3 h after SIT (p < 0.01) and after HIHVT (p < 0.001). However, PGC-1α protein was higher after HIHVT than after SIT (p < 0.05). Moreover, the AMPKpTHR172/AMPK ratio increased at post after SIT (p < 0.05), whereas this effect was delayed after HIHVT as it increased after 3 h (p < 0.05). In addition, VEGF transcription was higher in response to HIHVT (p < 0.05). In conclusion, SIT induces higher muscular stress than HIHVT without increasing systemic oxidation. In addition, HIHVT may induce more robust oxidative adaptations through PGC-1α and AMPK.
Haghani, Karimeh; Bakhtiyari, Salar; Doost Mohammadpour, Jafar
2016-04-01
Diabetes mellitus is a group of metabolic diseases characterized by chronic hyperglycemia. Trigonella foenum-graecum (fenugreek) and swimming training have previously been reported to have hypoglycemic and antioxidant effects. We aimed to evaluate the effects of swimming training and fenugreek aqueous extract, alone and in combination, on plasma glucose and cardiac antioxidant enzymes activity of streptozotocin-induced diabetes in rats. We divided 70 male Wistar rats equally into 7 groups: diabetic control (DC), healthy control (HC), swimming (S), fenugreek seed extract (1.74 g/kg) (F1), fenugreek seed extract (0.87 g/kg) (F2), swimming + fenugreek seed extract (1.74 g/kg) (SF1), and swimming + fenugreek seed extract (0.87 g/kg) (SF2). We used streptozotocin for the induction of diabetes. Statistical analyses were performed using the statistical program SPSS. We did not detect any significant differences in body weight in the F1, F2, S, SF1 and SF2 groups compared with the DC group (p>0.05). The results also revealed that the hypoglycemic effect of combined swimming and fenugreek was significantly stronger (p<0.05) than either of those alone. The F1, S, SF1 and SF2 groups showed improved superoxide dismutase activity with respect to the DC group (p<0.05). Catalase activity in the F1, S, SF1 and SF2 groups were significantly higher than those of the DC group (p<0.05). Glutathione peroxidase activity in the S, SF1 and SF2 groups were significantly increased compared with the DC group (p<0.05). Our findings suggest that the combination of fenugreek seed extract and swimming could be useful for the treatment of hyperglycemia and cardiac oxidative stress induced by type 1 diabetes mellitus. Copyright © 2016 Canadian Diabetes Association. Published by Elsevier Inc. All rights reserved.
Does water temperature influence the performance of key survival skills?
Schnitzler, C; Button, C; Seifert, L; Armbrust, G; Croft, J L
2018-03-01
Aquatic survival skills may be compromised in cold water thereby increasing the likelihood of drowning. This study compared physiological, psychological, and behavioral responses of humans treading water and swimming in cold and temperate water. Thirty-eight participants were classified as inexperienced (n = 9), recreational (n = 15), or skilled (n = 10) swimmers. They performed 3 tasks: treading water (120 seconds), swim at "comfortable" pace, and swim at "fast" pace in 2 water conditions (28°C vs 10°C). Heart rate, oxygen uptake, psychometric variables, spatio-temporal (swim speed, stroke rate, and stroke length), and coordination type were examined as a function of expertise. Tasks performed in cold water-generated higher cardiorespiratory responses (HR = 145 ± 16 vs 127 ± 21 bpm) and were perceived about 2 points more strenuous on the Borg scale on average (RPE = 14.9 ± 2.8 vs 13.0 ± 2.0). The voluntary durations of both treading water (60 ± 32 vs 91 ± 33 seconds) and swimming at a comfortable pace (66 ± 22 vs 103 ± 34 seconds) were significantly reduced in cold water. However, no systematic changes in movement pattern type could be determined in either the treading water task or the swimming tasks. Water temperature influences the physical demands of these aquatic skills but not necessarily the behavior. Training treading water and swimming skills in temperate water seems to transfer to cold water, but we recommend training these skills in a range of water conditions to help adapt to the initial "cold-shock" response. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Geurtsen, W
2000-12-01
Several reports indicate an increased prevalence of dental erosion among intensive swimmers due to low pH gas-chlorinated pool water. Contrary to other extrinsic factors which induce erosion located on the facial aspect, low pH pool water results in general dental erosion. Additionally, a case report is presented which describes the very rapid occurrence of excessive general dental erosion of a competitive swimmer due to gas-chlorinated pool water within 27 days. The observation of several authors as well as this case underscore the significance of a regular pH monitoring of chlorinated swimming pool water. The high incidence indicates that dental erosion due to frequent swimming is of considerable diagnostic and therapeutic significance. Furthermore, it is recommended to fluoridate the teeth of intensive swimmers regularly to prevent dental erosion.
Acute leptospirosis in a triathlete.
Abb, Jochen
2002-01-01
We report the case of a 38-year-old male patient with acute leptospirosis. The most probable cause of infection was repeated and prolonged exposure to contaminated river water (Neckar and Enz rivers) while preparing for participation in long-distance triathlon (swimming, biking, and running) competitions.
Ju, Xiaowei; Zhu, Lvgang; Huang, Changlin; Huang, Tao; Zuo, Xincheng; Gao, Chunfang
2013-01-01
Fatigue is synonymous with a wide spectrum of familiar physiological conditions, from pathology and general health, to sport and physical exercise. Strenuous, prolonged exercise training causes fatigue. Although several studies have investigated the effects of electrical stimulation frequency on muscle fatigue, the effects of percutaneous pulse current stimulation on fatigue in the hepatic tissue of trained rats is still unclear. In order to find an effective strategy to prevent fatigue or enhance recovery, the effects of pulse current on endurance exercise and its anti-fatigue properties in exercised rats were studied. Rats were subjected to one, three or five weeks of swimming exercise training. After exercise training, rats in the treated group received daily applications of pulse current. All rats were sacrificed after one, three or five weeks of swimming exercise, and the major biochemical indexes were measured in serum and liver. The results demonstrate that pulse current could prolong the exhaustion swimming time, as well as decrease serum ALT, AST and LD levels and liver MDA content. It also elevated serum LDH activity, liver SOD activity and glycogen content. Furthermore, pulse current increased the expression of Bcl-2 and decreased the expression of Bax. Taken together, these results show that pulse current can elevate endurance capacity and facilitate recovery from fatigue. PMID:24116026
Effectiveness of a Multisystem Aquatic Therapy for Children with Autism Spectrum Disorders.
Caputo, Giovanni; Ippolito, Giovanni; Mazzotta, Marina; Sentenza, Luigi; Muzio, Mara Rosaria; Salzano, Sara; Conson, Massimiliano
2018-06-01
Aquatic therapy improves motor skills of persons with Autism Spectrum Disorders (ASD), but its usefulness for treating functional difficulties needs to be verified yet. We tested effectiveness of a multisystem aquatic therapy on behavioural, emotional, social and swimming skills of children with ASD. Multisystem aquatic therapy was divided in three phases (emotional adaptation, swimming adaptation and social integration) implemented in a 10-months-programme. At post-treatment, the aquatic therapy group showed significant improvements relative to controls on functional adaptation (Vineland Adaptive Behavior Scales), emotional response, adaptation to change and on activity level (Childhood Autism Rating Scale). Swimming skills learning was also demonstrated. Multisystem aquatic therapy is useful for ameliorating functional impairments of children with ASD, going well beyond a swimming training.
Optimal Body Size and Limb Length Ratios Associated with 100-m Personal-Best Swim Speeds.
Nevill, Alan M; Oxford, Samuel W; Duncan, Michael J
2015-08-01
This study aims to identify optimal body size and limb segment length ratios associated with 100-m personal-best (PB) swim speeds in children and adolescents. Fifty national-standard youth swimmers (21 males and 29 females age 11-16 yr; mean ± SD age, 13.5 ± 1.5 yr) participated in the study. Anthropometry comprised stature; body mass; skinfolds; maturity offset; upper arm, lower arm, and hand lengths; and upper leg, lower leg, and foot lengths. Swimming performance was taken as the PB time recorded in competition for the 100-m freestyle swim. To identify the optimal body size and body composition components associated with 100-m PB swim speeds (having controlled for age and maturity offset), we adopted a multiplicative allometric log-linear regression model, which was refined using backward elimination. Lean body mass was the singularly most important whole-body characteristic. Stature and body mass did not contribute to the model, suggesting that the advantage of longer levers was limb-specific rather than a general whole-body advantage. The allometric model also identified that having greater limb segment length ratios [i.e., arm ratio = (low arm)/(upper arm); foot-to-leg ratio = (foot)/(lower leg)] was key to PB swim speeds. It is only by adopting multiplicative allometric models that the above mentioned ratios could have been derived. The advantage of having a greater lower arm is clear; however, having a shorter upper arm (achieved by adopting a closer elbow angle technique or by possessing a naturally endowed shorter upper arm), at the same time, is a new insight into swimming performance. A greater foot-to-lower-leg ratio suggests that a combination of larger feet and shorter lower leg length may also benefit PB swim speeds.
ERIC Educational Resources Information Center
Hunsaker, Scot
1998-01-01
Examines the use of lighting, both artificial and natural, that can enhance the aesthetic quality and functionality of areas with indoor swimming pools. Discusses glare and shadow-reduction measures that aid competitive events, including lighting above and below water levels, and highlights lighting issues during televised events. Descriptions of…
Rep. Smith, Lamar [R-TX-21
2010-05-06
House - 05/27/2010 Referred to the Subcommittee on Higher Education, Lifelong Learning, and Competitiveness. (All Actions) Tracker: This bill has the status Agreed to in HouseHere are the steps for Status of Legislation:
Pang, Xu; Yuan, Xing-Zhong; Cao, Zhen-Dong; Fu, Shi-Jian
2013-01-01
To investigate the effects of temperature and exercise training on swimming performance in juvenile qingbo (Spinibarbus sinensis), we measured the following: (1) the resting oxygen consumption rate (MO(2rest)), critical swimming speed (U(crit)) and active oxygen consumption rate (MO(2active)) of fish at acclimation temperatures of 10, 15, 20, 25 and 30 °C and (2) the MO(2rest), U(crit) and MO(2active) of both exercise-trained (exhaustive chasing training for 14 days) and control fish at both low and high acclimation temperatures (15 and 25 °C). The relationship between U(crit) and temperature (T) approximately followed a bell-shaped curve as temperature increased: U(crit) = 8.21/{1 + [(T - 27.2)/17.0]²} (R² = 0.915, P < 0.001, N = 40). The optimal temperature for maximal U(crit) (8.21 BL s(-1)) in juvenile qingbo was 27.2 °C. Both the MO(2active) and the metabolic scope (MS, MO(2active) - MO(2rest)) of qingbo increased with temperature from 10 to 25 °C (P < 0.05), but there were no significant differences between fish acclimated to 25 and 30 °C. The relationships between MO(2active) or MS and temperature were described as MO(2active) = 1,214.29 /{1 + [(T - 28.8)/10.6]²} (R² = 0.911, P < 0.001, N = 40) and MS = 972.67/{1 + [(T - 28.0)/9.34]²} (R² = 0.878, P < 0.001, N = 40). The optimal temperatures for MO(2active) and MS in juvenile qingbo were 28.8 and 28.0 °C, respectively. Exercise training resulted in significant increases in both U(crit) and MO(2active) at a low temperature (P < 0.05), but training exhibited no significant effect on either U(crit) or MO(2active) at a high temperature. These results suggest that exercise training had different effects on swimming performance at different temperatures. These differences may be related to changes in aerobic metabolic capability, arterial oxygen delivery, available dissolved oxygen, imbalances in ion fluxes and stimuli to remodel tissues with changes in temperature.
Galbraith, Andy; Willmott, Aimee
2018-03-01
Effective warm-ups are attributed to several temperature-related mechanisms. Strategies during the transition phase, preceding swimming competition, have been shown to prolong temperature-related warm-up effects. The purpose of this study was to evaluate the effects of two different clothing strategies during the transition phase, on subsequent 100-m maximal swimming performance. Nine competitive swimmers (3 female, 21 ± 3 yrs; 6 male 20 ± 2 yrs, mean performance standard 702 FINA Points, mean 100-m seasons best time 61.54 s) completed their own 30-min individual pool warm-up, followed by 7-min changing time and a 30-min transition phase, straight into a 100-m maximal effort time-trial. During the transition phase, swimmers remained seated, either wearing warm or limited clothing. Swimmers returned 1 week later, where clothing conditions were alternated. Post-transition phase skin and core temperature remained higher in the warm clothing condition compared to the limited clothing condition (Mean Core: 36.90 ± 0.17°C, 36.61 ± 0.15°C, P < .01; Mean Skin: 33.49 ± 0.59°C, 31.94 ± 0.59°C, P < .01). One hundred-metre finish times were 0.6% faster in the warm clothing condition compared to the limited clothing condition (62.63 ± 7.69 s, 63.00 ± 7.75 s, P < .01). Wearing warm clothing during a 30-min transition phase improved swimming performance by 0.6%, compared to limited clothing.
Lisbôa, Felipe D; Turnes, Tiago; Cruz, Rogério S O; Raimundo, João A G; Pereira, Gustavo S; Caputo, Fabrizio
2017-05-01
The present study aimed to determine the effects of ischemic preconditioning on performance in three successive 50-m swimming trials and to measure stroke rate, stroke length and blood lactate accumulation. Counterbalanced, repeated-measures cross-over study. On two separate days, eleven competitive male swimmers (20±3 years, 182±5cm, 77±5kg) performed three successive 50-m trials in a 50-m swimming pool, preceded by intermittent bilateral cuff inflation (4× 5-min of blood flow restriction+5-min of cuff deflation) at either 220 for thighs and 180mmHg for arms (ischemic preconditioning) or 20mmHg for both limbs (control-treatment). The 50-m trials were conducted 1-, 2-, and 8-h after the procedure. While no ergogenic effect of ischemic preconditioning was observed for 1-h (0.4%, 95% confidence limits of ±0.6%, p=0.215), there were clear beneficial effects of ischemic preconditioning on 2- and 8-h (1.0% and 1.2%, respectively; 95% confidence limits of ±0.6% in both cases, p≤0.002). Furthermore, ischemic preconditioning increased blood lactate accumulation in 2-(p<0.001) and 8-h (p=0.010) and stroke rate for 2- and 8-h in specific 10-m segments (p<0.05). These findings suggest a time-dependent effect of ischemic preconditioning on 50-m swimming performance for competitive athletes, with the time window of the beneficial effect starting after about 2-h and lasting for at least 8-h after ischemic preconditioning. This change in performance was accompanied by an increase in blood lactate accumulation and faster strokes in front crawl. Copyright © 2016 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.
Moving in extreme environments: open water swimming in cold and warm water
2014-01-01
Open water swimming (OWS), either ‘wild’ such as river swimming or competitive, is a fast growing pastime as well as a part of events such as triathlons. Little evidence is available on which to base high and low water temperature limits. Also, due to factors such as acclimatisation, which disassociates thermal sensation and comfort from thermal state, individuals cannot be left to monitor their own physical condition during swims. Deaths have occurred during OWS; these have been due to not only thermal responses but also cardiac problems. This paper, which is part of a series on ‘Moving in Extreme Environments’, briefly reviews current understanding in pertinent topics associated with OWS. Guidelines are presented for the organisation of open water events to minimise risk, and it is concluded that more information on the responses to immersion in cold and warm water, the causes of the individual variation in these responses and the precursors to the cardiac events that appear to be the primary cause of death in OWS events will help make this enjoyable sport even safer. PMID:24921042
NASA Astrophysics Data System (ADS)
Richardson, S. I. Heath; Baggaley, A. W.; Hill, N. A.
2018-02-01
We study the effects of imposed three-dimensional flows on the trajectories and mixing of gyrotactic swimming microorganisms and identify phenomena not seen in flows restricted to two dimensions. Through numerical simulation of Taylor-Green and Arnold-Beltrami-Childress (ABC) flows, we explore the role that the flow and the cell shape play in determining the long-term configuration of the cells' trajectories, which often take the form of multiple sinuous and helical "plumelike" structures, even in the chaotic ABC flow. This gyrotactic suppression of Lagrangian chaos persists even in the presence of random noise. Analytical solutions for a number of cases reveal the how plumes form and the nature of the competition between torques acting on individual cells. Furthermore, studies of Lyapunov exponents reveal that, as the ratio of cell swimming speed relative to the flow speed increases from zero, the initial chaotic trajectories are first suppressed and then give way to a second unexpected window of chaotic trajectories at speeds greater than unity, before suppression of chaos at high relative swimming speeds.
da Silva, Márcia F; Natali, Antônio J; da Silva, Edson; Gomes, Gilton J; Teodoro, Bruno G; Cunha, Daise N Q; Drummond, Lucas R; Drummond, Filipe R; Moura, Anselmo G; Belfort, Felipe G; de Oliveira, Alessandro; Maldonado, Izabel R S C; Alberici, Luciane C
2015-07-15
We tested the effects of swimming training and insulin therapy, either alone or in combination, on the intracellular calcium ([Ca(2+)]i) homeostasis, oxidative stress, and mitochondrial functions in diabetic rat hearts. Male Wistar rats were separated into control, diabetic, or diabetic plus insulin groups. Type 1 diabetes mellitus was induced by streptozotocin (STZ). Insulin-treated groups received 1 to 4 UI of insulin daily for 8 wk. Each group was divided into sedentary or exercised rats. Trained groups were submitted to swimming (90 min/day, 5 days/wk, 8 wk). [Ca(2+)]i transient in left ventricular myocytes (LVM), oxidative stress in LV tissue, and mitochondrial functions in the heart were assessed. Diabetes reduced the amplitude and prolonged the times to peak and to half decay of the [Ca(2+)]i transient in LVM, increased NADPH oxidase-4 (Nox-4) expression, decreased superoxide dismutase (SOD), and increased carbonyl protein contents in LV tissue. In isolated mitochondria, diabetes increased Ca(2+) uptake, susceptibility to permeability transition pore (MPTP) opening, uncoupling protein-2 (UCP-2) expression, and oxygen consumption but reduced H2O2 release. Swimming training corrected the time course of the [Ca(2+)]i transient, UCP-2 expression, and mitochondrial Ca(2+) uptake. Insulin replacement further normalized [Ca(2+)]i transient amplitude, Nox-4 expression, and carbonyl content. Alongside these benefits, the combination of both therapies restored the LV tissue SOD and mitochondrial O2 consumption, H2O2 release, and MPTP opening. In conclusion, the combination of swimming training with insulin replacement was more effective in attenuating intracellular Ca(2+) disruptions, oxidative stress, and mitochondrial dysfunctions in STZ-induced diabetic rat hearts. Copyright © 2015 the American Physiological Society.
Ultraendurance triathlon participation: typical race preparation of lower level triathletes.
Gulbin, J P; Gaffney, P T
1999-03-01
This study sought to describe the training preparations and performances of lower level ultraendurance triatheletes. The lower level or typical ultraendurance athlete was defined as any participant eligible to compete, irrespective of ability. participants completed a retrospective questionnaire related to their athletic background, triathlon experience and performances, and training preparation. all competitors in the 1995 Lanzarote Ironman (i.m.) triathlon had the opportunity to complete the questionnaire in the days prior to the race. 242 (230 m, 12 f) or 45% of the entire race field completed the questionnaire. measures of central tendency were used to describe all data. Forward step-wise multiple regression techniques were used to predict performance from training variables. Statistical significance was accepted at p < 0.05. Mean finish time for all study participants was 11.76 hours. Subjects were 34.2 +/- 8.8 years, 1.77 +/- 0.07 m, and 70.8 +/- 7.1 kg. They had 6.0 +/- 3.2 years experience in triathlon, had completed 3.0 +/- 4.1 IM races, and spent 21.5 +/- 10.8 weeks preparing for the IM. Training distances/week for swimming, cycling and running, were 8.8 +/- 4.3 km, 270 +/- 107 km, and 58.2 +/- 21.9 km, at a pace of 18.1 min/km, 31.8 km/hr, and 4.55 min/km respectively. Previous best performances in Olympic distance triathlon (1.5/40/10) coupled with weekly cycling distances and longest training ride, could partially predict overall performance (R2 = 0.57). Finishing an IM requires less training than has been previously reported in studies that have primarily focused on elite competitors. Additionally, training distances appear to be a more important factor for competitive success than training paces.
Pack, Stephen; Kelly, Sasha; Arvinen-Barrow, Monna
2017-10-01
The purpose of this study was to explore the role of swimming on Paralympic athletes' perceptions of self and identity development. A hermeneutic phenomenological approach was taken. During semi-structured interviews, five Paralympic swimmers (aged 20-24 years) were asked questions about their swimming career, perceptions of self, integration, and impairment. Interviews were audio-recorded and transcribed verbatim. An Interpretative Phenomenological Analysis yielded three superordinate themes: (a) "One of the crowd"; none of the participants viewed themselves as disabled, nor as supercrips; these perceptions stemmed from family-, school-, and swimming-related experiences, (b) "Becoming me"; participation in swimming facilitated self- and social-acceptance, and identity development, and c) "A badge of honor"; swimming presented opportunity to present and reinforce a positive identity. Swimming experiences enabled the participants to enhance personal and social identities, integrate through pro-social mechanisms, and to develop a career path following retirement from competition. Implications for rehabilitation Offering equal sporting opportunities for people with/without physical disability can help facilitate social integration and act as a buffer against stigmatization. Our research suggests that participation in sport had afforded the participants a heightened sense of self-concept, independence, ability and corresponding pride. When working with individuals with physical disabilities, rehabilitation professionals could utilize sport as a means of increasing an individual's feelings of independence, confidence and normalization. As such, part of rehabilitation should be to ensure opportunities for sport participation for people with physical disability are available for people of all ages.
Heat stroke risk for open-water swimmers during long-distance events.
Macaluso, Filippo; Barone, Rosario; Isaacs, Ashwin W; Farina, Felicia; Morici, Giuseppe; Di Felice, Valentina
2013-12-01
Open-water swimming is a rapidly growing sport discipline worldwide, and clinical problems associated with long-distance swimming are now better recognized and managed more effectively. The most prevalent medical risk associated with an open-water swimming event is hypothermia; therefore, the Federation Internationale De Natation (FINA) has instituted 2 rules to reduce this occurrence related to the minimum water temperature and the time taken to complete the race. Another medical risk that is relevant to open-water swimmers is heat stroke, a condition that can easily go unnoticed. The purpose of this review is to shed light on this physiological phenomenon by examining the physiological response of swimmers during long-distance events, to define a maximum water temperature limit for competitions. We conclude that competing in water temperatures exceeding 33°C should be avoided. Copyright © 2013 Wilderness Medical Society. Published by Elsevier Inc. All rights reserved.
Inertial Sensor Technology for Elite Swimming Performance Analysis: A Systematic Review
Mooney, Robert; Corley, Gavin; Godfrey, Alan; Quinlan, Leo R; ÓLaighin, Gearóid
2015-01-01
Technical evaluation of swimming performance is an essential factor of elite athletic preparation. Novel methods of analysis, incorporating body worn inertial sensors (i.e., Microelectromechanical systems, or MEMS, accelerometers and gyroscopes), have received much attention recently from both research and commercial communities as an alternative to video-based approaches. This technology may allow for improved analysis of stroke mechanics, race performance and energy expenditure, as well as real-time feedback to the coach, potentially enabling more efficient, competitive and quantitative coaching. The aim of this paper is to provide a systematic review of the literature related to the use of inertial sensors for the technical analysis of swimming performance. This paper focuses on providing an evaluation of the accuracy of different feature detection algorithms described in the literature for the analysis of different phases of swimming, specifically starts, turns and free-swimming. The consequences associated with different sensor attachment locations are also considered for both single and multiple sensor configurations. Additional information such as this should help practitioners to select the most appropriate systems and methods for extracting the key performance related parameters that are important to them for analysing their swimmers’ performance and may serve to inform both applied and research practices. PMID:26712760
Martens, Jonas; Daly, Daniel; Deschamps, Kevin; Staes, Filip; Fernandes, Ricardo J
2016-12-01
Variability of electromyographic (EMG) recordings is a complex phenomenon rarely examined in swimming. Our purposes were to investigate inter-individual variability in muscle activation patterns during front crawl swimming and assess if there were clusters of sub patterns present. Bilateral muscle activity of rectus abdominis (RA) and deltoideus medialis (DM) was recorded using wireless surface EMG in 15 adult male competitive swimmers. The amplitude of the median EMG trial of six upper arm movement cycles was used for the inter-individual variability assessment, quantified with the coefficient of variation, coefficient of quartile variation, the variance ratio and mean deviation. Key features were selected based on qualitative and quantitative classification strategies to enter in a k-means cluster analysis to examine the presence of strong sub patterns. Such strong sub patterns were found when clustering in two, three and four clusters. Inter-individual variability in a group of highly skilled swimmers was higher compared to other cyclic movements which is in contrast to what has been reported in the previous 50years of EMG research in swimming. This leads to the conclusion that coaches should be careful in using overall reference EMG information to enhance the individual swimming technique of their athletes. Copyright © 2016 Elsevier Ltd. All rights reserved.
Training Guide to Cerebral Palsy Sports. Third Edition.
ERIC Educational Resources Information Center
Jones, Jeffery A., Ed.
This official training manual of the United States Cerebral Palsy Athletic Association includes the latest coaching and training techniques specific to all sports in the national program. The book features guidelines for coaching over a dozen sports, including soccer, swimming, cycling, and track and field. It contains everything coaches,…
Fantozzi, Silvia; Giovanardi, Andrea; Magalhães, Fabrício Anício; Di Michele, Rocco; Cortesi, Matteo; Gatta, Giorgio
2016-01-01
The analysis of the joint kinematics during swimming plays a fundamental role both in sports conditioning and in clinical contexts. Contrary to the traditional video analysis, wearable inertial-magnetic measurements units (IMMUs) allow to analyse both the underwater and aerial phases of the swimming stroke over the whole length of the swimming pool. Furthermore, the rapid calibration and short data processing required by IMMUs provide coaches and athletes with an immediate feedback on swimming kinematics during training. This study aimed to develop a protocol to assess the three-dimensional kinematics of the upper limbs during swimming using IMMUs. Kinematics were evaluated during simulated dry-land swimming trials performed in the laboratory by eight swimmers. A stereo-photogrammetric system was used as the gold standard. The results showed high coefficient of multiple correlation (CMC) values, with median (first-third quartile) of 0.97 (0.93-0.95) and 0.99 (0.97-0.99) for simulated front-crawl and breaststroke, respectively. Furthermore, the joint angles were estimated with an accuracy increasing from distal to proximal joints, with wrist indices showing median CMC values always higher than 0.90. The present findings represent an important step towards the practical use of technology based on IMMUs for the kinematic analysis of swimming in applied contexts.
Cravana, Cristina; Medica, P; Ragonese, G; Fazio, E
2017-01-01
To investigate the effects of training sessions on circulating β-endorphin changes in sport horses before and after competition and to ascertain whether competition would affect this response. A total of 24 trained jumping horses were randomly assigned to one of two training groups: Group A (competing) and Group B (not competing). To determined plasma β-endorphin concentrations, two pre- and post-competition training weeks at aerobic workout and two competitive show jumping event days at anaerobic workout were measured before, 5 and 30 min after exercise. Exercise intensity is described using lactate concentrations and heart rate. The circuit design, intensity, and duration of training sessions were the same for both groups. In Group A, one-way analysis of variance for repeated measures (RM-ANOVA) showed significant effects of exercise on β-endorphin changes (F=14.41; p<0.001), only in the post-competition training sessions, while in Group B showed no significant effects. Two-way RM-ANOVA showed, after post-competition training sessions, a significant difference between Group A and Group B (F=6.235; p=0.023), with higher β-endorphin changes in Group A, compared to Group B. During the competitive show jumping sessions, one-way RM ANOVA showed significant effects of exercise on β-endorphin changes (F=51.10; p<0.001). The statistical analysis, in Group A, showed a significant difference between post-competition training and competitive exercise (F=6.32; p=0.024) with higher β-endorphin values in competitive sessions compared to those of post-competition training. Lactate concentrations seem to be the main factors being correlated with the raise of β-endorphin during anaerobic exercise of competitive events. Exercise of low intensity, as well as that one of training sessions, does not appear to stimulate a significant increased release of β-endorphin and it may depend on the duration of the exercise program. Moreover, the responses during exercise in the course of post-competition training sessions seem to be significantly different from those the pre-competition training. These data show that the preliminary competitive stress induced additional significant changes of β-endorphin pattern. It would reflect the need of a long-lasting modulation of fatigue and pain perception related to the effect of an additional physical and mental effort for the consecutive competitive and training sessions.
Swimming performance and unique wake topology of the sea hare (Aplysia)
NASA Astrophysics Data System (ADS)
Zhou, Zhuoyu; Mittal, Rajat
2018-03-01
The Aplysia, commonly referred to as the "sea hare," is a marine mollusc that swims using large-amplitude flapping of its wide, winglike parapodia. In this study, flow simulations with a relatively simple kinematical model are used to gain insights into the vortex dynamics, thrust generation, and energetics of locomotion for this animal. A unique vortex pattern characterized by three distinct trains of vortex ringlike structures is observed in the wake of this animal. These vortex rings are associated with a positive momentum flux in the wake that counteracts the drag generated by the body. Simulations indicate propulsive efficiencies of up to 24% and terminal swimming speeds of about 0.9 body length per cycle. Swimming speeds are found to increase with increasing parapodial flapping amplitude as well as wavelength of undulation.
Casey, Amanda Faith; Rasmussen, Roy; Mackenzie, Sasho J; Glenn, Jillian
2010-07-01
To use dual-energy x-ray absorptiometry (DXA) to measure the effects of a 16-week community-based swim training program on percent body fat in children and adolescents with intellectual disability (ID). Convenience sample. University sport complex and exercise science laboratory. Children and adolescents (n=8; mean age +/- SD, 13.1 +/- 3.4 y), 2 girls and 6 boys with ID, of varying fat levels (11%-35%). A swim training program lasting for the duration of 16 weeks with three 1-hour sessions held at a 25-m pool each week. Assessing percent body fat at pretest and posttest through the use of DXA. After the 16-week exercise training program, we observed a 1.2% median increase in body fat percentage with a range from -0.3% to 4.5%. Wilcoxon matched-pairs signed-ranks tests suggest that these results are statistically significant (P=.039; exact). Exercise training alone proved ineffectual in reducing percent body fat in 8 children and adolescents with ID. Further research should consider implementing a combined diet and exercise program. To gauge the effectiveness of intervention programs, valid methods and complex measurement tools such as DXA should be used to assess changes in percent body fat in such a heterogeneous population. Copyright 2010 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.
Innate immune response adaptation in mice subjected to administration of DMBA and physical activity
ABDALLA, DOUGLAS R.; ALEIXO, ANDRÉ ADRIANO ROCHA; MURTA, EDDIE F.C.; MICHELIN, MÁRCIA A.
2014-01-01
Although there is growing interest in studies that promote the benefits of exercise and the correlation between exercise and fighting cancer, previous studies have not been able to elucidate the underlying mechanisms. The aim of the present study was to investigate cytokine synthesis by peritoneal macrophages in the presence of mammary tumors and the effect of physical activity. Female BALB/c virgin mice (age, eight weeks) were obtained for the present study and divided into four groups: A no tumor/non-trained control group; a no tumor/trained group subjected to swim training; a tumor/non-trained group in which the mice received the carcinogenic drug, DMBA and a tumor/trained group in which the mice were subjected to DMBA and swim training protocols. Following the experimental period, immune cells were collected from the peritoneal fluid, placed in culture medium and stimulated with lipopolysaccharide. The presence of the cluster of differentiation-14 marker and expression of the interleukin (IL)-12 cytokine was assessed by flow cytometry and measured via an enzyme-linked immunosorbent assay. The following cytokines were also identified: Interferon-γ, IL-4, IL-10, IL-12, tumor necrosis factor-α and transforming growth factor-β. Physical activity increased the quantity of IL-12 producing macrophages, whereas the presence of a tumor decreased the quantity of macrophages expressing IL-12. Tumor induction, in the absence of swim training, reduced macrophage-profile 1 (M1) cytokine levels while increasing the presence of macrophage-profile 2 cytokines. Physical activity in mice with tumors resulted in reductions in tumor development and promoted immune system polarization towards an antitumor M1 response pattern profile. PMID:24520305
Innate immune response adaptation in mice subjected to administration of DMBA and physical activity.
Abdalla, Douglas R; Aleixo, André Adriano Rocha; Murta, Eddie F C; Michelin, Márcia A
2014-03-01
Although there is growing interest in studies that promote the benefits of exercise and the correlation between exercise and fighting cancer, previous studies have not been able to elucidate the underlying mechanisms. The aim of the present study was to investigate cytokine synthesis by peritoneal macrophages in the presence of mammary tumors and the effect of physical activity. Female BALB/c virgin mice (age, eight weeks) were obtained for the present study and divided into four groups: A no tumor/non-trained control group; a no tumor/trained group subjected to swim training; a tumor/non-trained group in which the mice received the carcinogenic drug, DMBA and a tumor/trained group in which the mice were subjected to DMBA and swim training protocols. Following the experimental period, immune cells were collected from the peritoneal fluid, placed in culture medium and stimulated with lipopolysaccharide. The presence of the cluster of differentiation-14 marker and expression of the interleukin (IL)-12 cytokine was assessed by flow cytometry and measured via an enzyme-linked immunosorbent assay. The following cytokines were also identified: Interferon-γ, IL-4, IL-10, IL-12, tumor necrosis factor-α and transforming growth factor-β. Physical activity increased the quantity of IL-12 producing macrophages, whereas the presence of a tumor decreased the quantity of macrophages expressing IL-12. Tumor induction, in the absence of swim training, reduced macrophage-profile 1 (M1) cytokine levels while increasing the presence of macrophage-profile 2 cytokines. Physical activity in mice with tumors resulted in reductions in tumor development and promoted immune system polarization towards an antitumor M1 response pattern profile.
Influence of Competitive-Anxiety on Heart Rate Variability in Swimmers.
Fortes, Leonardo S; da Costa, Bruna D V; Paes, Pedro P; do Nascimento Júnior, José R A; Fiorese, Lenamar; Ferreira, Maria E C
2017-12-01
The aim of this study was to analyze the relationship between competitive anxiety and heart rate variability (HRV) in swimming athletes. A total of 66 volunteers (41 male and 27 female) who swam the 400-m freestyle in the Brazilian Swimming Championships participated. Thirty minutes before the 400-m freestyle event, the athletes answered the Competitive Anxiety Inventory (CSAI-2R) questionnaire, then underwent anthropometric (body weight, height, and skinfold thickness) and HRV measurements. Then, at a second meeting, held 3 h after the 400-m freestyle event, the athletes returned to the evaluation room for HRV measurement (Polar ® RS800cx, Kempele, Finland). Multiple linear regression was used to evaluate the relationship between competitive anxiety and HRV. The multiple linear regression was performed in three blocks (block 1: cognitive anxiety, block 2: somatic anxiety, and block 3: self-confidence), adopting the forward model. The results indicated a significant association between cognitive anxiety (p = 0.001) and HRV. An increased magnitude of the association was observed when somatic anxiety was inserted in the model (p = 0.001). In contrast, self-confidence showed, which was inserted in block 3, no relationship with HRV (p = 0.27). It was concluded that cognitive and somatic anxieties were associated with the HRV of swimmers. Athletes with a high magnitude of cognitive and/or somatic anxiety demonstrated more significant autonomic nervous system disturbance. Practically, psychological interventions are needed to improve anxiety states that are specific to perform well, and to improve HRV.
ERIC Educational Resources Information Center
Jull, Stephanie; Mirenda, Pat
2016-01-01
Several recent studies have shown that children with autism spectrum disorder (ASD) are less physically active than their typically developing peers and are thus at risk of health problems associated with inactivity (e.g., obesity or diabetes). There is a need to examine the effectiveness of interventions such as swimming that are aimed at…
Swimming with Sharks: A Physical Educator's Guide to Effective Crowdsourcing
ERIC Educational Resources Information Center
Bulger, Sean M.; Jones, Emily M.; Katz, Nicole; Shrewsbury, Gentry; Wood, Justin
2016-01-01
The reality-competition television series Shark Tank affords up-and-coming entrepreneurs the opportunity to make a formal business presentation to a panel of potential investors. Adopting a similar framework, entrepreneurial teachers have started using web-based collaborative fundraising or crowdsourcing as a tool to build program capacity with…
[Leisure-time sport activities and cardiac outpatient therapy in coronary patients].
Heitkamp, Hans-Christian; Schimpf, Thomas M; Hipp, Arno; Niess, Andreas
2005-03-01
Exercise intensity in coronary patients is controlled by heart rate measurements. Very few investigations have compared the maximum heart rate in cardiac outpatient groups, in leisure-time sport activities, and especially in swimming. Within different exercise conditions 21 coronary patients, nine in well-compensated cardiac condition joining a training group and twelve joining the exercise group with lower intensity, without signs of heart failure, engaged in an incremental bicycle ergometry. A six-lead ECG was derived at the same time with a 24-h ECG. The performance tolerance was measured by the pulse limit derived in 20 patients; one patient failed to show signs of subjective or objective ischemia. During a 24-h ECG monitoring, the patients took part in a 1-h standardized cardiac outpatient program, a standardized swimming program 4 x 25 m, and a typical self-selected leisure-time activity. The patients showed a peak work capacity of 2.2 W/kg and a symptom-free work capacity of 1.3 W/kg. The derived upper heart rate limit was passed during swimming by 19, during leisure-time activity by 16, and during cardiac outpatient program by two patients. The maximum of the mean overriding the limit occurred in leisure-time activity. Signs of ischemia occurred during ergometry in 15, during swimming training in ten patients, during leisure-time activity in eight, and during cardiac outpatient therapy in one. Arrhythmia < Lown IVa was documented on the ergometer in 15, during leisure-time sport activity in 15, during cardiac outpatient therapy in 17, and during swimming in eight patients. Arrhythmia Lown IVa occurred in one patient each during ergometry, leisure sports, and during the night. Coronary patients are in danger to exercise beyond the pulse limit during swimming and other leisure-time sports and not during cardiac outpatient therapy. The upper heart rate limit should be observed during swimming and other endurance leisure-time activities, and is of little importance during cardiac outpatient therapy.
Effect of Dietary Nitrate Supplementation on Swimming Performance in Trained Swimmers.
Lowings, Sam; Shannon, Oliver Michael; Deighton, Kevin; Matu, Jamie; Barlow, Matthew John
2017-08-01
Nitrate supplementation appears to be most ergogenic when oxygen availability is restricted and subsequently may be particularly beneficial for swimming performance due to the breath-hold element of this sport. This represents the first investigation of nitrate supplementation and swimming time-trial (TT) performance. In a randomized double-blind repeated-measures crossover study, ten (5 male, 5 female) trained swimmers ingested 140ml nitrate-rich (~12.5mmol nitrate) or nitrate-depleted (~0.01mmol nitrate) beetroot juice. Three hours later, subjects completed a maximal effort swim TT comprising 168m (8 × 21m lengths) backstroke. Preexercise fractional exhaled nitric oxide concentration was significantly elevated with nitrate compared with placebo, Mean (SD): 17 (9) vs. 7 (3)p.p.b., p = .008. Nitrate supplementation had a likely trivial effect on overall swim TT performance (mean difference 1.22s; 90% CI -0.18-2.6s; 0.93%; p = .144; d = 0.13; unlikely beneficial (22.6%), likely trivial (77.2%), most unlikely negative (0.2%)). The effects of nitrate supplementation during the first half of the TT were trivial (mean difference 0.29s; 90% CI -0.94-1.5s; 0.46%; p = .678; d = 0.05), but there was a possible beneficial effect of nitrate supplementation during the second half of the TT (mean difference 0.93s; 90% CI 0.13-1.70s; 1.36%; p = .062; d = 0.24; possibly beneficial (63.5%), possibly trivial (36.3%), most unlikely negative (0.2%)). The duration and speed of underwater swimming within the performance did not differ between nitrate and placebo (both p > .30). Nitrate supplementation increased nitric oxide bioavailability but did not benefit short-distance swimming performance or the underwater phases of the TT. Further investigation into the effects of nitrate supplementation during the second half of performance tests may be warranted.
Cravana, Cristina; Medica, P.; Ragonese, G.; Fazio, E.
2017-01-01
Aim: To investigate the effects of training sessions on circulating β-endorphin changes in sport horses before and after competition and to ascertain whether competition would affect this response. Materials and Methods: A total of 24 trained jumping horses were randomly assigned to one of two training groups: Group A (competing) and Group B (not competing). To determined plasma β-endorphin concentrations, two pre- and post-competition training weeks at aerobic workout and two competitive show jumping event days at anaerobic workout were measured before, 5 and 30 min after exercise. Exercise intensity is described using lactate concentrations and heart rate. The circuit design, intensity, and duration of training sessions were the same for both groups. Results: In Group A, one-way analysis of variance for repeated measures (RM-ANOVA) showed significant effects of exercise on β-endorphin changes (F=14.41; p<0.001), only in the post-competition training sessions, while in Group B showed no significant effects. Two-way RM-ANOVA showed, after post-competition training sessions, a significant difference between Group A and Group B (F=6.235; p=0.023), with higher β-endorphin changes in Group A, compared to Group B. During the competitive show jumping sessions, one-way RM ANOVA showed significant effects of exercise on β-endorphin changes (F=51.10; p<0.001). The statistical analysis, in Group A, showed a significant difference between post-competition training and competitive exercise (F=6.32; p=0.024) with higher β-endorphin values in competitive sessions compared to those of post-competition training. Conclusion: Lactate concentrations seem to be the main factors being correlated with the raise of β-endorphin during anaerobic exercise of competitive events. Exercise of low intensity, as well as that one of training sessions, does not appear to stimulate a significant increased release of β-endorphin and it may depend on the duration of the exercise program. Moreover, the responses during exercise in the course of post-competition training sessions seem to be significantly different from those the pre-competition training. These data show that the preliminary competitive stress induced additional significant changes of β-endorphin pattern. It would reflect the need of a long-lasting modulation of fatigue and pain perception related to the effect of an additional physical and mental effort for the consecutive competitive and training sessions. PMID:28246449
da Rocha, Guilherme L; Crisp, Alex H; de Oliveira, Maria R M; da Silva, Carlos A; Silva, Jadson O; Duarte, Ana C G O; Sene-Fiorese, Marcela; Verlengia, Rozangela
2016-01-01
This study aimed to investigate the effects of interval and continuous training on the body mass gain and adiposity levels of rats fed a high-fat diet. Forty-eight male Sprague-Dawley rats were randomly divided into two groups, standard diet and high-fat diet, and received their respective diets for a period of four weeks without exercise stimuli. After this period, the animals were randomly divided into six groups (n = 8): control standard diet (CS), control high-fat diet (CH), continuous training standard diet (CTS), continuous training high-fat diet (CTH), interval training standard diet (ITS), and interval training high-fat diet (ITH). The interval and continuous training consisted of a swimming exercise performed over eight weeks. CH rats had greater body mass gain, sum of adipose tissues mass, and lower serum high density lipoprotein values than CS. The trained groups showed lower values of feed intake, caloric intake, body mass gain, and adiposity levels compared with the CH group. No significant differences were observed between the trained groups (CTS versus ITS and CTH versus ITH) on body mass gains and adiposity levels. In conclusion, both training methodologies were shown to be effective in controlling body mass gain and adiposity levels in high-fat diet fed rats.
Prevalence of Dental Erosion among the Young Regular Swimmers in Kaunas, Lithuania.
Zebrauskas, Andrius; Birskute, Ruta; Maciulskiene, Vita
2014-04-01
To determine prevalence of dental erosion among competitive swimmers in Kaunas, the second largest city in Lithuania. The study was designed as a cross-sectional survey, with a questionnaire and clinical examination protocols. The participants were 12 - 25 year-old swimmers regularly practicing in the swimming pools of Kaunas. Of the total of 132 participants there were 76 (12 - 17 year-old) and 56 (18 - 25 year-old) individuals; in Groups 1 and 2, respectively. Participants were examined for dental erosion, using a portable dental unit equipped with fibre-optic light, compressed air and suction, and standard dental instruments for oral inspection. Lussi index was applied for recording dental erosion. The completed questionnaires focused on the common erosion risk factors were returned by all participants. Dental erosion was found in 25% of the 12 - 17 year-olds, and in 50% of 18 - 25 years-olds. Mean value of the surfaces with erosion was 6.31 (SD 4.37). All eroded surfaces were evaluated as grade 1. Swimming training duration and the participants' age correlated positively (Kendall correlation, r = 0.65, P < 0.001), meaning that older swimmers had practiced for longer period. No significant correlation between occurrence of dental erosion and the analyzed risk factors (gastroesophageal reflux disease, frequent vomiting, dry mouth, regular intake of acidic medicines, carbonated drinks) was found in both study groups. Prevalence of dental erosion of very low degree was high among the regular swimmers in Kaunas, and was significantly related to swimmers' age.
Benefits Analysis of the Naval Junior Reserve Officers Training Corps
1992-06-01
Football, baseball, softball, soccer , 2086 (54.7) track, swimming, wrestling, weightlifting, volleyball, or other sports) Church youth group 1382 (36.3...clubs a b 78. Academic clubs (For example: uth. science, tlanguae) a b 79. Sports (Football, baseball, softball, soccer , track, a b swimming, wrestling...the Players Champion Golf Tournament Seneca Valley High School, MD Kanzano High School, NM Neptune High School, NJ Episcopal High School, IA Valley
Specific aspects of contemporary triathlon: implications for physiological analysis and performance.
Bentley, David J; Millet, Grégoire P; Vleck, Verónica E; McNaughton, Lars R
2002-01-01
Triathlon competitions are performed over markedly different distances and under a variety of technical constraints. In 'standard-distance' triathlons involving 1.5km swim, 40km cycling and 10km running, a World Cup series as well as a World Championship race is available for 'elite' competitors. In contrast, 'age-group' triathletes may compete in 5-year age categories at a World Championship level, but not against the elite competitors. The difference between elite and age-group races is that during the cycle stage elite competitors may 'draft' or cycle in a sheltered position; age-group athletes complete the cycle stage as an individual time trial. Within triathlons there are a number of specific aspects that make the physiological demands different from the individual sports of swimming, cycling and running. The physiological demands of the cycle stage in elite races may also differ compared with the age-group format. This in turn may influence performance during the cycle leg and subsequent running stage. Wetsuit use and drafting during swimming (in both elite and age-group races) result in improved buoyancy and a reduction in frontal resistance, respectively. Both of these factors will result in improved performance and efficiency relative to normal pool-based swimming efforts. Overall cycling performance after swimming in a triathlon is not typically affected. However, it is possible that during the initial stages of the cycle leg the ability of an athlete to generate the high power outputs necessary for tactical position changes may be impeded. Drafting during cycling results in a reduction in frontal resistance and reduced energy cost at a given submaximal intensity. The reduced energy expenditure during the cycle stage results in an improvement in running, so an athlete may exercise at a higher percentage of maximal oxygen uptake. In elite triathlon races, the cycle courses offer specific physiological demands that may result in different fatigue responses when compared with standard time-trial courses. Furthermore, it is possible that different physical and physiological characteristics may make some athletes more suited to races where the cycle course is either flat or has undulating sections. An athlete's ability to perform running activity after cycling, during a triathlon, may be influenced by the pedalling frequency and also the physiological demands of the cycle stage. The technical features of elite and age-group triathlons together with the physiological demands of longer distance events should be considered in experimental design, training practice and also performance diagnosis of triathletes.
Espada, Mario C; Reis, Joana F; Almeida, Tiago F; Bruno, Paula M; Vleck, Veronica E; Alves, Francisco B
2015-10-01
The purpose of this study was to understand the ventilatory and physiological responses immediately below and above the maximal lactate steady-state (MLSS) velocity and to determine the relationship of oxygen uptake (VO2) kinetics parameters with performance, in swimmers. Competitive athletes (N = 12) completed in random order and on different days a 400-m all-out test, an incremental step test comprising 5 × 250- and 1 × 200-m stages and 30 minutes at a constant swimming velocity (SV) at 87.5, 90, and 92.5% of the maximal aerobic velocity for MLSS velocity (MLSSv) determination. Two square-wave transitions of 500 m, 2.5% above and below the MLSSv were completed to determine VO2 on-kinetics. End-exercise VO2 at 97.5 and 102.5% of MLSSv represented, respectively, 81 and 97% of VO2max; the latter was not significantly different from maximal VO2 (VO2max). The VO2 at MLSSv (49.3 ± 9.2 ml·kg(-1)·min(-1)) was not significantly different from the second ventilatory threshold (VT2) (51.3 ± 7.6 ml·kg(-1)·min(-1)). The velocity associated with MLSS seems to be accurately estimated by the SV at VT2 (vVT2), and vVO2max also seems to be estimated with accuracy from the central 300-m mean velocity of a 400-m trial, indicators that represent a helpful tool for coaches. The 400-m swimming performance (T400) was correlated with the time constant of the primary phase VO2 kinetics (τp) at 97.5% MLSSv, and T800 was correlated with τp in both 97.5 and 102.5% of MLSSv. The assessment of the VO2 kinetics in swimming can help coaches to build training sets according to a swimmer's individual physiological response.
Tracer diffusion in active suspensions
NASA Astrophysics Data System (ADS)
Burkholder, Eric W.; Brady, John F.
2017-05-01
We study the diffusion of a Brownian probe particle of size R in a dilute dispersion of active Brownian particles of size a , characteristic swim speed U0, reorientation time τR, and mechanical energy ksTs=ζaU02τR/6 , where ζa is the Stokes drag coefficient of a swimmer. The probe has a thermal diffusivity DP=kBT /ζP , where kBT is the thermal energy of the solvent and ζP is the Stokes drag coefficient for the probe. When the swimmers are inactive, collisions between the probe and the swimmers sterically hinder the probe's diffusive motion. In competition with this steric hindrance is an enhancement driven by the activity of the swimmers. The strength of swimming relative to thermal diffusion is set by Pes=U0a /DP . The active contribution to the diffusivity scales as Pes2 for weak swimming and Pes for strong swimming, but the transition between these two regimes is nonmonotonic. When fluctuations in the probe motion decay on the time scale τR, the active diffusivity scales as ksTs/ζP : the probe moves as if it were immersed in a solvent with energy ksTs rather than kBT .
Yang, Qiang; Wang, Wen-wen; Ma, Pu; Ma, Zhong-xuan; Hao, Meng; Adelusi, Temitope I; Lei-Du; Yin, Xiao-Xing; Lu, Qian
2017-01-01
Objective(s): Increasing evidence suggests that regular physical exercise improves type 2 diabetes mellitus (T2DM). However, the potential beneficial effects of swimming on insulin resistance and lipid disorder in T2DM, and its underlying mechanisms remain unclear. Materials and Methods: Rats were fed with high fat diet and given a low dosage of Streptozotocin (STZ) to induce T2DM model, and subsequently treated with or without swimming exercise. An 8-week swimming program (30, 60 or 120 min per day, 5 days per week) decreased body weight, fasting blood glucose and fasting insulin. Results: Swimming ameliorated lipid disorder, improved muscular atrophy and revealed a reduced glycogen deposit in skeletal muscles of diabetic rats. Furthermore, swimming also inhibited the activation of Wnt3a/β-catenin signaling pathway, decreased Wnt3a mRNA and protein level, upregulated GSK3β phosphorylation activity and reduced the expression of β-catenin phosphorylation in diabetic rats. Conclusion: The trend of the result suggests that swimming exercise proved to be a potent ameliorator of insulin resistancein T2DM through the modulation of Wnt3a/β-catenin pathway and therefore, could present a promising therapeutic measure towards the treatment of diabetes and its relatives. PMID:29299199
Diversi, Tara; Franks-Kardum, Vanessa; Climstein, Mike
2016-01-01
The purpose of this study was to determine if cold water swimmers (CWS) developed hypothermia over a 6-h cold water endurance swim and whether body composition, stroke rate (SR) or personal characteristics correlated with core temperature (TC) change. Nine experienced male and female CWS who were aspiring English Channel (EC) swimmers volunteered to participate. Subjects aimed to complete their 6-h EC qualifying swim (water 15-15.8 °C/air 15-25 °C) while researchers intermittently monitored TC and SR. Data obtained included anthropometry (height, mass, segmental body composition), training volume and EC completion. Of the nine swimmers who volunteered, all successfully completed their EC qualifying swim. Six CWS had complete data included in analysis. One CWS demonstrated hypothermia (34.8 °C) at 6-h. TC rate of decline was slower in the first 3 h (-0.06 °C/hr) compared to the last 3 h (-0.36 °C/hr) of the swim. Older age was significantly correlated to TC change (r = -0.901, p < 0.05) and SR change (r = -0.915, p < 0.05). Absolute and percentage body fat (BF) were not significantly associated with higher TC. Mean SR over the 6-h swim was 57.8 spm (range 48-73 spm), and a significant (p < 0.05) decline in SR was observed over the 6 h (-9.7 %). A strong, positive correlation was found between SR change between 3 and 6 h and TC over the 6 h (r = 0.840, p < 0.05) and TC from 3-6 h (r = 0.827, p < 0.05). Seven of the nine participants (77.8 %) in this study successfully completed the EC crossing. Successful EC swimmers swam in the pool and open water (OW); however, they swam significantly [t (7) = -2.433, p < 0.05] more kilometres (M = 19.09 km/wk ± 5.55) in OW than unsuccessful (M = 9 km/wk ± 1.41) EC swimmers. There was a significant relationship between EC crossing time and height (r = -0.817, p < 0.05), but no other variables and EC crossing time. Cold water endurance swim (CWES) of 6-h duration at 15-16 °C resulted in TC reduction in the majority of swimmers regardless of anthropometry. More research is required to determine why some CWS are able to maintain their TC throughout a CWES. Our results indicate that older swimmers are at greater risk of developing hypothermia, and that SR decline is an indicator of TC decline. Our results also suggest that OW swimming training combined with pool training is important for EC swim success.
Pool Rules: A Survival Guide for Parents and Children
ERIC Educational Resources Information Center
Grosse, Susan J.
2008-01-01
In most sports and physical activities rules are present to facilitate participation, outlining courtesy during play as well as establishing guidelines for keeping any competition fair. In contrast, rules for appropriate behavior in swimming pools serve a much more important purpose--that of ensuring health and safety for all participants.…
Physiological adaptation during short distance triathlon swimming and cycling sectors simulation.
González-Haro, Carlos; González-de-Suso, José Manuel; Padulles, Josep Ma; Drobnic, Franchek; Escanero, Jesús Fernando
2005-11-15
The aim of this study was to typify cardiorespiratory and metabolic adaptation capacity at race pace of high-level triathletes during simulations of short distance triathlon swimming sector, first transition and cycling sector. Six national and international-level triathletes performed a 1500 m swimming trial followed by a transition and one hour on ergocycle at race pace, with sequenced measures of blood lactate concentration, gas exchange and heart rate recording. The mean speed obtained in the swimming sector was 1.29+/-0.07 m s(-1), matching 98+/-2% of MAS (Maximal Aerobic Speed), lactate concentration 6.8+/-2.1 mM and heart rate 162+/-15 beats min(-1). In the cycling sector, the mean power was 266+/-34 W, matching 77+/-10% of MAP (Maximal Aerobic Power), oxygen uptake 3788+/-327 mL min(-1) (82.8% of VO2max), heart rate 162+/-13 beats min(-1) (92% of maximal HR) and ventilation 112.8+/-20.8 L min(-1). MAS was correlated with performance in swimming sector (r = 0.944; P < 0.05). Despite intake 1.08+/-0.44 L of a solution with 8% of sugars, a significant loss of body weight (2.80%; P < 0.01) was observed. Changes in cycling power, speed and frequency, especially towards the end of the effort, were also found. By contrast, differences in lactate concentration and in cardiorespiratory or metabolic variables between the end of the swimming sector and the end of the first transition did not appear. In conclusion, this study remarks different relative intensities in cycling and swimming sectors. The observed loss of body weight does not modify pedalling economy in national and international-level athletes during the cycling sector, where effort intensity adapts itself to the one found in individual lactate threshold. However, changes in competition tactics and other effects, such as drafting in swimming and cycling, could alter the intensities established in this study for each sector.
Norton, Alice; Rollinson, David; Richards, Louisa; Webster, Joanne
2008-01-01
Background The chances of a schistosome cercaria encountering a suitable definitive host may be enhanced by emergence from the molluscan intermediate host with maximal glycogen stores and by an appropriate chronobiological rhythm. This study aimed to identify and characterize the effects of potential competitive interactions in the snail host Biomphalaria glabrata, between the closely-related Schistosoma mansoni and S. rodhaini, on phenotypic behavioural traits. It was predicted that inter-specific competition would affect chronobiological emergence rhythms and reduce the activity of schistosome swimming behavioural traits. Biomphalaria glabrata snails (120) were exposed to either S. mansoni or S. rodhaini single infections, or a mixed infection of both species simultaneously and the resulting cercarial phenotypic traits were characterised. Cercariae were identified from co-exposed snails by amplification and sequencing of the mitochondrial cytochrome oxidase subunit 1 (CO1). Results S. mansoni and S. rodhaini largely maintained their distinct chronobiological rhythms after mixed exposures and infections. However, inter-specific competition appeared to result in a restriction of the shedding pattern of S. rodhaini and slight shift in the shedding pattern of S. mansoni. Inter-specific competition also significantly lowered hourly cercarial production for both parasite species in comparison to single exposures and infections and reduced cercarial swimming activity. Conclusion Inter-specific competition was shown to influence cercarial production, chronobiology and activity and should therefore be investigated further in field situations to determine the effects of these changes on parasite fitness (incorporating both host finding and infectivity) where these two species overlap. Importantly this competition did not result in a large change in chronobiological emergence of cercariae for either species indicating that it would not have a large influence on the species of hosts available for infection at time of emergence. This study has furthermore demonstrated the potential for phenotypic measures to provide markers for species-specific identification even in conditions of co-infection. PMID:19055722
Acevedo, E O; Meyers, M C; Hayman, M; Haskin, J
1997-03-01
This study presents the use of physiological principles and assessment techniques in addressing four objectives that can enhance a swimmer's likelihood of successfully swimming the English Channel. The four objective were: (1) to prescribe training intensities and determine ideal swimming pace; (2) to determine the amount of insulation needed, relative to heat produced, to diminish the likelihood of the swimmer suffering from hypothermia; (3) to calculate the caloric expenditure for the swim and the necessary glucose replacement required to prevent glycogen depletion; and (4) to determine the rate of acclimatization to cold water (15.56 C/60 F). The subject participated in several pool swimming data collection sessions including a tethered swim incremental protocol to determine peak oxygen consumption and onset of lactate accumulation and several steady state swims to determine ideal swimming pace at 4.0 mM/L of lactate. Additionally, these swims provided information on oxygen consumption, which in combination with ultrasound assessment of subcutaneous fat was used to assess heat production and insulation capabilities. Finally, the subject participated in 18 cold water immersions to document acclimatization rate. The data demonstrated the high fitness level of this subject and indicated that at a stroke rate of 63 stokes/min, HR was 130 heats/min and lactate was 4 mM/L. At this swimming pace the swimmer would need to consume 470 kcal of glucose/hr. In addition, the energy produced at this swim pace was 13.25 kcal/min while the energy lost at the present subcutaneous fat quantity was 13.40 kcal/min, requiring a fat weight gain of 6,363.03 g (13.88 lbs) to resist heat loss. Finally, the data from the cold water immersions suggested that acclimatization occurred following two weeks of immersions. There results were provided to the swimmer and utilized in making decisions in preparation for the swim.
The relationship between sources of motivation and level of practice in young Portuguese swimmers.
Salselas, V; Gonzalez-Boto, R; Tuero, C; Marquez, S
2007-06-01
The aim of this study was to examine the relationship between participation motives and level of practice in young Portuguese swimmers and to investigate whether swimmers with a different expertise differ in their reasons for participation involvement. A total of 155 subjects (68 male and 87 female), aged 7 to 18 years, responded to the Portuguese versions of the Participation Motivation Inventory. The subjects were divided into those participating in learn-to swim programs (n=40), advanced programs (n=49) or competition (n=56). A significant multivariate effect was obtained for level of practice, with children involved in learn-to swim programs rating fitness, competition, general affiliation, technical skills and fun significantly lower in importance than the other two groups. A 2 (subject gender) x3 (practice level) MANCOVA, with age at dropout, revealed that the effect of the covariate itself was not significant, but a main effect was found for gender, differing boys and girls only in the emotion factor. A significant interaction was also detected between gender and participation level, with a higher importance given to general affiliation by girls in comparison to boys in the advanced programs and competition categories. Our results in a sample of Portuguese swimmers indicate the existence of multiple motives for participation and significant differences in motivational factors in relation to the practice level.
Shan, Lingling; Wang, Bin; Gao, Guizhen; Cao, Wengen; Zhang, Yunkun
2013-10-15
l-Arginine (l-Arg) supplementation has been shown to enhance physical exercise capacity and delay onset of fatigue. This work investigated the potential beneficial mechanism(s) of l-Arg supplementation by examining its effect on the cellular oxidative and nitrosative stress pathways in the exercised rats. Forty-eight rats were randomly divided into six groups: sedentary control; sedentary control with l-Arg treatment; endurance training (daily swimming training for 8 wk) control; endurance training with l-Arg treatment; an exhaustive exercise (one time swimming to fatigue) control; and an exhaustive exercise with l-Arg treatment. l-Arg (500 mg/kg body wt) or saline was given to rats by intragastric administration 1 h before the endurance training and the exhaustive swimming test. Expression levels and activities of the l-Arg/nitric oxide (NO) pathway components and parameters of the oxidative stress and antioxidant defense capacity were investigated in l-Arg-treated and control rats. The result show that the l-Arg supplementation completely reversed the exercise-induced activation of NO synthase and superoxide dismutase, increased l-Arg transport capacity, and increased NO and anti-superoxide anion levels. These data demonstrate that l-Arg supplementation effectively reduces the exercise-induced imbalance between oxidative stress and antioxidant defense capacity, and this modulation is likely mediated through the l-Arg/NO pathways. The findings of this study improved our understanding of how l-Arg supplementation prevents elevations of reactive oxygen species and favorably enhances the antioxidant defense capacity during physical exercise.
Metabolic Effects of Chronic Heavy Physical Training on Male Age Group Swimmers.
ERIC Educational Resources Information Center
Caffrey, Garret P.; And Others
This study attempts to appraise the effectiveness of chronic heavy exercise on 13 male swimmers from 10 to 17 years of age. The experimental group trained six days a week, often with more than one workout per day. During this period, the principles of interval training were employed in conjunction with high-intensity swimming. At the completion of…
Connolly, Luke J; Nordsborg, Nikolai B; Nyberg, Michael; Weihe, Pál; Krustrup, Peter; Mohr, Magni
2016-10-01
We tested the hypothesis that low-volume high-intensity swimming has a larger impact on insulin sensitivity and glucose control than high-volume low-intensity swimming in inactive premenopausal women with mild hypertension. Sixty-two untrained premenopausal women were randomised to an inactive control (n = 20; CON), a high-intensity low-volume (n = 21; HIT) or a low-intensity high-volume (n = 21; LIT) training group. During the 15-week intervention period, HIT performed 3 weekly 6-10 × 30-s all-out swimming intervals (average heart rate (HR) = 86 ± 3 % HRmax) interspersed by 2-min recovery periods and LIT swam continuously for 1 h at low intensity (average HR = 73 ± 3 % HRmax). Fasting blood samples were taken and an oral glucose tolerance test (OGTT) was conducted pre- and post-intervention. After HIT, resting plasma [insulin] was lowered (17 ± 34 %; P < 0.05) but remained similar after LIT and CON. Following HIT, 60-min OGTT plasma [insulin] and [glucose] was lowered (24 ± 30 % and 10 ± 16 %; P < 0.05) but remained similar after LIT and CON. Total area under the curve for plasma [glucose] was lower (P < 0.05) after HIT than LIT (660 ± 141 vs. 860 ± 325 mmol min L(-1)). Insulin sensitivity (HOMA-IR) had increased (P < 0.05) by 22 ± 34 % after HIT, with no significant change after LIT or CON, respectively. Plasma soluble intracellular cell adhesion molecule 1 was lowered (P < 0.05) by 4 ± 8 and 3 ± 9 % after HIT and CON, respectively, while plasma soluble vascular cell adhesion molecule 1 had decreased (P < 0.05) by 8 ± 23 % after HIT only. These findings suggest that low-volume high-intensity intermittent swimming is an effective and time-efficient training strategy for improving insulin sensitivity, glucose control and biomarkers of vascular function in inactive, middle-aged mildly hypertensive women.
da Rocha, Guilherme L.; Crisp, Alex H.; de Oliveira, Maria R. M.; da Silva, Carlos A.; Silva, Jadson O.; Duarte, Ana C. G. O.; Sene-Fiorese, Marcela; Verlengia, Rozangela
2016-01-01
This study aimed to investigate the effects of interval and continuous training on the body mass gain and adiposity levels of rats fed a high-fat diet. Forty-eight male Sprague-Dawley rats were randomly divided into two groups, standard diet and high-fat diet, and received their respective diets for a period of four weeks without exercise stimuli. After this period, the animals were randomly divided into six groups (n = 8): control standard diet (CS), control high-fat diet (CH), continuous training standard diet (CTS), continuous training high-fat diet (CTH), interval training standard diet (ITS), and interval training high-fat diet (ITH). The interval and continuous training consisted of a swimming exercise performed over eight weeks. CH rats had greater body mass gain, sum of adipose tissues mass, and lower serum high density lipoprotein values than CS. The trained groups showed lower values of feed intake, caloric intake, body mass gain, and adiposity levels compared with the CH group. No significant differences were observed between the trained groups (CTS versus ITS and CTH versus ITH) on body mass gains and adiposity levels. In conclusion, both training methodologies were shown to be effective in controlling body mass gain and adiposity levels in high-fat diet fed rats. PMID:26904718
Focus on Preschool Aquatics: Child Care Regulations.
ERIC Educational Resources Information Center
Sayre, Nancy E.
This paper proposes state regulations for the training of child care staff members in developmentally appropriate safe aquatic practices, outlines required features of any pools that children visit, and suggests safe practices for water-related activities at child care centers and swimming pools. The staff training regulation suggestions include…
The Functions and Methods of Mental Training on Competitive Sports
NASA Astrophysics Data System (ADS)
Xiong, Jianshe
Mental training is the major training method of the competitive sports and the main factor of athletes skill and tactics level.By combining the psychological factor with the current competitive sports characteristics, this paper presents the function of mental training forward athletes, and how to improve the comprehensive psychological quality by using mental training.
Abdalla, Douglas R; Murta, Eddie F C; Michelin, Márcia A
2013-05-01
This study aims to investigate cytokine synthesis by lymphocytes in the presence of mammary tumors and the interaction with physical activity. For this study, we used 56 female Balb/c, 8-week-old, virgin mice with a body mass between 20 and 30 g. The mice were divided into four groups: a no tumor/nontrained control group; a no tumor/trained group subjected to physical training of swimming in water (30 ± 4°C) for 45 min, five times per week for 8 weeks; a tumor/nontrained (sedentary) group in which the animals received 7,12-dimethylbenzanthracene [(DMBA) 1 mg/ml weekly for 6 weeks)]; and a tumor/trained group in which animals were subjected to the aforementioned DMBA tumor induction and swim training protocols. After the experimental period, immune cells were collected from spleen cell specimens, placed in culture, and stimulated with lipopolysaccharide. The presence of cluster of differentiation (CD)3, CD4, and CD8 markers and the expression of interferon-γ, interleukin (IL)-2, IL-4, IL-10, IL-12, transforming growth factor β, and tumor necrosis factor α cytokines were assessed by flow cytometry and enzyme-linked immunosorbent assay. Physical activity increased the quantities of lymphocytes producing interferon γ, IL-2, IL-12, and tumor necrosis factor α and decreased the quantities of lymphocytes and macrophages expressing IL-4, IL-10, and transforming growth factor β. In contrast, tumor induction, in the absence of swim training, reduced Th1 cytokine levels while increasing the presence of Th2 cytokines and Treg cells. Physical activity promoted reductions in the incidence of tumor development and promoted immune system polarization toward an antitumor Th1 response pattern profile.
Validity of Postexercise Measurements to Estimate Peak VO2 in 200-m and 400-m Maximal Swims.
Rodríguez, Ferran A; Chaverri, Diego; Iglesias, Xavier; Schuller, Thorsten; Hoffmann, Uwe
2017-06-01
To assess the validity of postexercise measurements to estimate oxygen uptake (V˙O 2 ) during swimming, we compared V˙O 2 measured directly during an all-out 200-m swim with measurements estimated during 200-m and 400-m maximal tests using several methods, including a recent heart rate (HR)/V˙O 2 modelling procedure. 25 elite swimmers performed a 200-m maximal swim where V˙O 2 was measured using a swimming snorkel connected to a gas analyzer. The criterion variable was V˙O 2 in the last 20 s of effort, which was compared with the following V˙O 2peak estimates: 1) first 20-s average; 2) linear backward extrapolation (BE) of the first 20 and 30 s, 3×20-s, 4×20-s, and 3×20-s or 4×20-s averages; 3) semilogarithmic BE at the same intervals; and 4) predicted V˙O 2peak using mathematical modelling of 0-20 s and 5-20 s during recovery. In 2 series of experiments, both of the HR/V˙O 2 modelled values most accurately predicted the V˙O 2peak (mean ∆=0.1-1.6%). The BE methods overestimated the criterion values by 4-14%, and the single 20-s measurement technique yielded an underestimation of 3.4%. Our results confirm that the HR/V˙O 2 modelling technique, used over a maximal 200-m or 400-m swim, is a valid and accurate procedure for assessing cardiorespiratory and metabolic fitness in competitive swimmers. © Georg Thieme Verlag KG Stuttgart · New York.
Physical Forces Shape Group Identity of Swimming Pseudomonas putida Cells.
Espeso, David R; Martínez-García, Esteban; de Lorenzo, Víctor; Goñi-Moreno, Ángel
2016-01-01
The often striking macroscopic patterns developed by motile bacterial populations on agar plates are a consequence of the environmental conditions where the cells grow and spread. Parameters such as medium stiffness and nutrient concentration have been reported to alter cell swimming behavior, while mutual interactions among populations shape collective patterns. One commonly observed occurrence is the mutual inhibition of clonal bacteria when moving toward each other, which results in a distinct halt at a finite distance on the agar matrix before having direct contact. The dynamics behind this phenomenon (i.e., intolerance to mix in time and space with otherwise identical others) has been traditionally explained in terms of cell-to-cell competition/cooperation regarding nutrient availability. In this work, the same scenario has been revisited from an alternative perspective: the effect of the physical mechanics that frame the process, in particular the consequences of collisions between moving bacteria and the semi-solid matrix of the swimming medium. To this end, we set up a simple experimental system in which the swimming patterns of Pseudomonas putida were tested with different geometries and agar concentrations. A computational analysis framework that highlights cell-to-medium interactions was developed to fit experimental observations. Simulated outputs suggested that the medium is compressed in the direction of the bacterial front motion. This phenomenon generates what was termed a compression wave that goes through the medium preceding the swimming population and that determines the visible high-level pattern. Taken together, the data suggested that the mechanical effects of the bacteria moving through the medium created a factual barrier that impedes to merge with neighboring cells swimming from a different site. The resulting divide between otherwise clonal bacteria is thus brought about by physical forces-not genetic or metabolic programs.
Maladen, Ryan D.; Ding, Yang; Umbanhowar, Paul B.; Kamor, Adam; Goldman, Daniel I.
2011-01-01
We integrate biological experiment, empirical theory, numerical simulation and a physical model to reveal principles of undulatory locomotion in granular media. High-speed X-ray imaging of the sandfish lizard, Scincus scincus, in 3 mm glass particles shows that it swims within the medium without using its limbs by propagating a single-period travelling sinusoidal wave down its body, resulting in a wave efficiency, η, the ratio of its average forward speed to the wave speed, of approximately 0.5. A resistive force theory (RFT) that balances granular thrust and drag forces along the body predicts η close to the observed value. We test this prediction against two other more detailed modelling approaches: a numerical model of the sandfish coupled to a discrete particle simulation of the granular medium, and an undulatory robot that swims within granular media. Using these models and analytical solutions of the RFT, we vary the ratio of undulation amplitude to wavelength (A/λ) and demonstrate an optimal condition for sand-swimming, which for a given A results from the competition between η and λ. The RFT, in agreement with the simulated and physical models, predicts that for a single-period sinusoidal wave, maximal speed occurs for A/λ ≈ 0.2, the same kinematics used by the sandfish. PMID:21378020
Tracer diffusion in active suspensions.
Burkholder, Eric W; Brady, John F
2017-05-01
We study the diffusion of a Brownian probe particle of size R in a dilute dispersion of active Brownian particles of size a, characteristic swim speed U_{0}, reorientation time τ_{R}, and mechanical energy k_{s}T_{s}=ζ_{a}U_{0}^{2}τ_{R}/6, where ζ_{a} is the Stokes drag coefficient of a swimmer. The probe has a thermal diffusivity D_{P}=k_{B}T/ζ_{P}, where k_{B}T is the thermal energy of the solvent and ζ_{P} is the Stokes drag coefficient for the probe. When the swimmers are inactive, collisions between the probe and the swimmers sterically hinder the probe's diffusive motion. In competition with this steric hindrance is an enhancement driven by the activity of the swimmers. The strength of swimming relative to thermal diffusion is set by Pe_{s}=U_{0}a/D_{P}. The active contribution to the diffusivity scales as Pe_{s}^{2} for weak swimming and Pe_{s} for strong swimming, but the transition between these two regimes is nonmonotonic. When fluctuations in the probe motion decay on the time scale τ_{R}, the active diffusivity scales as k_{s}T_{s}/ζ_{P}: the probe moves as if it were immersed in a solvent with energy k_{s}T_{s} rather than k_{B}T.
Seifert, L; De Jesus, K; Komar, J; Ribeiro, J; Abraldes, J A; Figueiredo, P; Vilas-Boas, J P; Fernandes, R J
2016-06-01
The aim was to examine behavioural variability within and between individuals, especially in a swimming task, to explore how swimmers with various specialty (competitive short distance swimming vs. triathlon) adapt to repetitive events of sub-maximal intensity, controlled in speed but of various distances. Five swimmers and five triathletes randomly performed three variants (with steps of 200, 300 and 400m distances) of a front crawl incremental step test until exhaustion. Multi-camera system was used to collect and analyse eight kinematical and swimming efficiency parameters. Analysis of variance showed significant differences between swimmers and triathletes, with significant individual effect. Cluster analysis put these parameters together to investigate whether each individual used the same pattern(s) and one or several patterns to achieve the task goal. Results exhibited ten patterns for the whole population, with only two behavioural patterns shared between swimmers and triathletes. Swimmers tended to use higher hand velocity and index of coordination than triathletes. Mono-stability occurred in swimmers whatever the task constraint showing high stability, while triathletes revealed bi-stability because they switched to another pattern at mid-distance of the task. Finally, our analysis helped to explain and understand effect of specialty and more broadly individual adaptation to task constraint. Copyright © 2016 Elsevier B.V. All rights reserved.
Swim stress, motion, and deformation of active matter: effect of an external field.
Takatori, Sho C; Brady, John F
2014-12-21
We analyze the stress, dispersion, and average swimming speed of self-propelled particles subjected to an external field that affects their orientation and speed. The swimming trajectory is governed by a competition between the orienting influence (i.e., taxis) associated with the external (e.g., magnetic, gravitational, thermal, nutrient concentration) field versus the effects that randomize the particle orientations (e.g., rotary Brownian motion and/or an intrinsic tumbling mechanism like the flagella of bacteria). The swimmers' motion is characterized by a mean drift velocity and an effective translational diffusivity that becomes anisotropic in the presence of the orienting field. Since the diffusivity yields information about the micromechanical stress, the anisotropy generated by the external field creates a normal stress difference in the recently developed "swim stress" tensor [Takatori, Yan, and Brady, Phys. Rev. Lett., 2014]. This property can be exploited in the design of soft, compressible materials in which their size, shape, and motion can be manipulated and tuned by loading the material with active swimmers. Since the swimmers exert different normal stresses in different directions, the material can compress/expand, elongate, and translate depending on the external field strength. Such an active system can be used as nano/micromechanical devices and motors. Analytical solutions are corroborated by Brownian dynamics simulations.
Role of the adrenocortical reaction to physical load in increase in the working capacity of the body
NASA Technical Reports Server (NTRS)
Viru, A. A.
1977-01-01
The maximal duration of swimming by rats with a load of 3% of their body weight increased after 5 weeks of training. This time did not increase in animals receiving dexamethasone in the process of training. The blood corticosterone level of these rats with the maximal load increased less than that of animals trained without administration of dexamethasone.
The French press: a repeatable and high-throughput approach to exercising zebrafish (Danio rerio).
Usui, Takuji; Noble, Daniel W A; O'Dea, Rose E; Fangmeier, Melissa L; Lagisz, Malgorzata; Hesselson, Daniel; Nakagawa, Shinichi
2018-01-01
Zebrafish are increasingly used as a vertebrate model organism for various traits including swimming performance, obesity and metabolism, necessitating high-throughput protocols to generate standardized phenotypic information. Here, we propose a novel and cost-effective method for exercising zebrafish, using a coffee plunger and magnetic stirrer. To demonstrate the use of this method, we conducted a pilot experiment to show that this simple system provides repeatable estimates of maximal swim performance (intra-class correlation [ICC] = 0.34-0.41) and observe that exercise training of zebrafish on this system significantly increases their maximum swimming speed. We propose this high-throughput and reproducible system as an alternative to traditional linear chamber systems for exercising zebrafish and similarly sized fishes.
The French press: a repeatable and high-throughput approach to exercising zebrafish (Danio rerio)
Usui, Takuji; Noble, Daniel W.A.; O’Dea, Rose E.; Fangmeier, Melissa L.; Lagisz, Malgorzata; Hesselson, Daniel
2018-01-01
Zebrafish are increasingly used as a vertebrate model organism for various traits including swimming performance, obesity and metabolism, necessitating high-throughput protocols to generate standardized phenotypic information. Here, we propose a novel and cost-effective method for exercising zebrafish, using a coffee plunger and magnetic stirrer. To demonstrate the use of this method, we conducted a pilot experiment to show that this simple system provides repeatable estimates of maximal swim performance (intra-class correlation [ICC] = 0.34–0.41) and observe that exercise training of zebrafish on this system significantly increases their maximum swimming speed. We propose this high-throughput and reproducible system as an alternative to traditional linear chamber systems for exercising zebrafish and similarly sized fishes. PMID:29372124
[Swimming, physical activity and health: a historical perspective].
Conti, A A
2015-01-01
Swimming, which is the coordinated and harmonic movement of the human body inside a liquid medium by means of the combined action of the superior and inferior limbs, is a physical activity which is diffused throughout the whole world and it is practiced by healthy and non-healthy subjects. Swimming is one of the physical activities with less contraindications and, with limited exceptions, can be suggested to individuals of both sexes and of every age range, including the most advanced. Swimming requires energy both for the floating process and for the anterograde progression, with a different and variable osteo-arthro-muscular involvement according to the different styles. The energetic requirement is about four times that for running, with an overall efficiency inferior to 10%; the energetic cost of swimming in the female subject is approximately two thirds of that in the male subject. The moderate aerobic training typical of swimming is useful for diabetic and hypertensive individuals, for people with painful conditions of rachis, as also for obese and orthopaedic patients. Motor activity inside the water reduces the risk of muscular-tendinous lesions and, without loading the joints in excess, requires the harmonic activation of the whole human musculature. Swimming is an activity requiring multiple abilities, ranging from a sense of equilibrium to that of rhythm, from reaction speed to velocity, from joint mobility to resistance. The structured interest for swimming in the perspective of human health from the beginning of civilization, as described in this contribution, underlines the relevance attributed to this activity in the course of human history.
Modern Approaches to Training Competitive Locksmiths-Electricians in the EU Countries
ERIC Educational Resources Information Center
Roskvas, Ihor
2017-01-01
The article deals with the issues of modern approaches to training competitive locksmiths-electricians and the influence of effective management on the process of vocational training. The modern labour market needs concerning vocational training of highly qualified workers have been analyzed. The concept of a competitive worker has been revealed…
A Comparison of Training and Competition Demands in Semiprofessional Male Basketball Players
ERIC Educational Resources Information Center
Fox, Jordan L.; Stanton, Robert; Scanlan, Aaron T.
2018-01-01
Purpose: The purpose of this study was to quantify and compare training and competition demands in basketball. Methods: Fifteen semiprofessional male basketball players wore microsensors during physical conditioning training (PCT), games-based training (GBT), and competition to measure absolute and relative (·min[superscript -1]) PlayerLoad™ (PL)…
Intensive Training in Youth Sport: An Example of Unequal Opportunity.
ERIC Educational Resources Information Center
Rowley, Stephen R. W.; Graham, Philip J.
1999-01-01
Examined the social composition of an unselected sample of 282 English 8- to 16-year olds involved in intensive training in football, swimming, tennis, and gymnastics. Found that working-class children and those from single-parent families were underrepresented in all sports. Concluded that financial considerations and difficulties in accessing…
Sport commitment and participation in masters swimmers: the influence of coach and teammates.
Santi, Giampaolo; Bruton, Adam; Pietrantoni, Luca; Mellalieu, Stephen
2014-01-01
This study investigated how coach and teammates influence masters athletes' sport commitment, and the effect of functional and obligatory commitments on participation in masters swimming. The sample consisted of 523 masters swimmers (330 males and 193 females) aged between 22 and 83 years (M = 39.00, SD = 10.42). A bi-dimensional commitment scale was used to measure commitment dimensions and perceived influence from social agents. Structural equation modelling analysis was conducted to evaluate the influence of social agents on functional and obligatory commitments, and the predictive capabilities of the two types of commitment towards sport participation. Support provided by coach and teammates increased functional commitment, constraints from these social agents determined higher obligatory commitment, and coach constraints negatively impacted functional commitment. In addition, both commitment types predicted training participation, with functional commitment increasing participation in team training sessions, and obligatory commitment increasing the hours of individual training. The findings suggest that in order to increase participation in masters swimming teams and reduce non-supervised training, coach and teammates should exhibit a supportive attitude and avoid over expectation.
NAGWS Aquatics Guide: Tips and Techniques for Teachers and Coaches, August 1977-August 1979.
ERIC Educational Resources Information Center
Harris, Marjorie, Ed.
This manual is designed to serve as a teaching aid to coaches and physical educators in the field of women's aquatics. The articles cover the following subjects in the area of water sports: (1) standards in sports for girls and women; (2) women in Olympic swimming competition; (3) conditioning programs designed to attain physical fitness through…
... and lungs. Examples of aerobic exercise include walking, hiking, running, aerobic dance, biking, rowing, swimming, and cross- ... Examples of weight-bearing exercise include walking, yoga, hiking, climbing stairs, playing tennis, dancing, and strength training. ...
Social Competition in Rats: Cell Proliferation and Behavior
Hoshaw, Brian A.; Evans, Jennifer C.; Mueller, Bridget; Valentino, Rita J.; Lucki, Irwin
2007-01-01
Behavioral and physiological changes were studied following prolonged exposure to social competition in pairs of non food-deprived rats competing daily for a limited supply of graham cracker crumbs. Stable dominant-subordinate relationships developed in most pairs, as measured by feeding time, which were maintained over a 5–6-week study period. In other behavioral tests, subordinates demonstrated a decreased latency to immobility in the forced swim test compared with dominants, but no difference in locomotor activity. Subordinates had increased bladder size, decreased adrenal gland size, and a 35% reduction of hippocampus cell proliferation compared with the dominant member. Therefore, prolonged social competition, based on restricted access to palatable substances, produced hierarchies among individuals that were associated with differences in behavior, physiology and hippocampal cell proliferation. PMID:17045347
Ranjbari, Abbas; Azarbayjani, Mohammad Ali; Yusof, Ashril; Halim Mokhtar, Abdul; Akbarzadeh, Samad; Ibrahim, Mohamed Yousif; Tarverdizadeh, Bahman; Farzadinia, Parviz; Hajiaghaee, Reza; Dehghan, Firouzeh
2016-03-15
Urtica dioica (UD) has been identified as a traditional herbal medicine. This study aimed to investigate the effect of UD extract and swimming activity on diabetic parameters through in vivo and in vitro experiments. Adult WKY male rats were randomly distributed in nine groups: intact control, diabetic control, diabetic + 625 mg/kg, 1.25 g/kg UD, diabetic + 100 mg/kg Metformin, diabetic + swimming, diabetic + swimming 625 mg/kg, 1.25 g/kg UD, and diabetic +100 mg/kg Metformin + swimming. The hearts of the animals were punctured, and blood samples were collected for biochemical analysis. The entire pancreas was exposed for histologic examination. The effect of UD on insulin secretion by RIN-5F cells in 6.25 or 12.5 mM glucose dose was examined. Glucose uptake by cultured L6 myotubes was determined. The serum glucose concentration decreased, the insulin resistance and insulin sensitivity significantly increased in treated groups. These changes were more pronounced in the group that received UD extract and swimming training. Regeneration and less beta cell damage of Langerhans islets were observed in the treated groups. UD treatment increased insulin secretion in the RIN-5F cells and glucose uptake in the L6 myotubes cells. Swimming exercises accompanied by consuming UD aqueous extracts effectively improved diabetic parameters, repaired pancreatic tissues in streptozotocin-induced diabetics in vivo, and increased glucose uptake or insulin in UD-treated cells in vitro.
Sandbakk, Øyvind; Solli, Guro Strøm; Holmberg, Hans-Christer
2018-01-01
The current review summarizes scientific knowledge concerning sex differences in world-record performance and the influence of sport discipline and competition duration. In addition, the way that physiological factors relate to sex dimorphism is discussed. While cultural factors played a major role in the rapid improvement of performance of women relative to men up until the 1990s, sex differences between the world's best athletes in most events have remained relatively stable at approximately 8-12%. The exceptions are events in which upper-body power is a major contributor, where this difference is more than 12%, and ultraendurance swimming, where the gap is now less than 5%. The physiological advantages in men include a larger body size with more skeletal-muscle mass, a lower percentage of body fat, and greater maximal delivery of anaerobic and aerobic energy. The greater strength and anaerobic capacity in men normally disappear when normalized for fat-free body mass, whereas the higher hemoglobin concentrations lead to 5-10% greater maximal oxygen uptake in men with such normalization. The higher percentage of muscle mass in the upper body of men results in a particularly large sex difference in power production during upper-body exercise. While the exercise efficiency of men and women is usually similar, women have a better capacity to metabolize fat and demonstrate better hydrodynamics and more even pacing, which may be advantageous, in particular during long-lasting swimming competitions.
STS-45 backup Payload Specialist Chappell during water egress training at JSC
NASA Technical Reports Server (NTRS)
1991-01-01
STS-45 Atlantis, Orbiter Vehicle (OV) 104, backup Payload Specialist Charles R. Chappell, wearing launch and entry suit (LES), is suspended via his parachute harness above JSC's Weightless Environment Training Facility (WETF) Bldg 29 pool. Chappell will be dropped into the pool during the exercise which simulates a parachute landing into a body of water. SCUBA-equipped divers swimming in the pool will assist during the training.
Biomechanical and structural parameters of tendons in rats subjected to swimming exercise.
Bezerra, M A; Santos de Lira, K D; Coutinho, M P G; de Mesquita, G N; Novaes, K A; da Silva, R T B; de Brito Nascimento, A K; Inácio Teixeira, M F H B; Moraes, S R A
2013-12-01
The aim of this study was to evaluate the effect of swimming exercise, without overloading, on the biomechanical parameters of the calcaneal tendon of rats. 27 male Wistar rats (70 days) were distributed randomly into 2 groups, Control Group (CG; n=15) with restricted movements inside the cage and Swimming Group (SG; n=12), subjected to exercise training in a tank with a water temperature of 30±1°C, for 1 h/day, 5 days/week for 8 weeks. All animals were kept in a reversed light/dark cycle of 12 h with access to food and water ad libitum. After that, they were anesthetized and had their calcaneus tendons collected from their left rear paws. The tendon was submitted to a mechanical test on a conventional test machine. From the stress vs. strain curve, the biomechanical data were analyzed. For the statistical analysis, the Student-T test was used (p<0.05). Of the variables examined, the maximum tension (p=0.009), maximum force (p=0.03), energy of deformation/tendon cross sectional area (p=0.017) and elastic modulus of the tendon (p=0.013) showed positive outcomes in SG. There was no difference in the other parameters. The results indicate that the swimming exercise training, without overloading, was an important stimulus for improving the biomechanical parameters and structural properties of the calcaneal tendon. © Georg Thieme Verlag KG Stuttgart · New York.
Hernández-Ocaña, Betania; Pozos-Parra, Ma. Del Pilar; Mezura-Montes, Efrén; Portilla-Flores, Edgar Alfredo; Vega-Alvarado, Eduardo; Calva-Yáñez, Maria Bárbara
2016-01-01
This paper presents two-swim operators to be added to the chemotaxis process of the modified bacterial foraging optimization algorithm to solve three instances of the synthesis of four-bar planar mechanisms. One swim favors exploration while the second one promotes fine movements in the neighborhood of each bacterium. The combined effect of the new operators looks to increase the production of better solutions during the search. As a consequence, the ability of the algorithm to escape from local optimum solutions is enhanced. The algorithm is tested through four experiments and its results are compared against two BFOA-based algorithms and also against a differential evolution algorithm designed for mechanical design problems. The overall results indicate that the proposed algorithm outperforms other BFOA-based approaches and finds highly competitive mechanisms, with a single set of parameter values and with less evaluations in the first synthesis problem, with respect to those mechanisms obtained by the differential evolution algorithm, which needed a parameter fine-tuning process for each optimization problem. PMID:27057156
Hernández-Ocaña, Betania; Pozos-Parra, Ma Del Pilar; Mezura-Montes, Efrén; Portilla-Flores, Edgar Alfredo; Vega-Alvarado, Eduardo; Calva-Yáñez, Maria Bárbara
2016-01-01
This paper presents two-swim operators to be added to the chemotaxis process of the modified bacterial foraging optimization algorithm to solve three instances of the synthesis of four-bar planar mechanisms. One swim favors exploration while the second one promotes fine movements in the neighborhood of each bacterium. The combined effect of the new operators looks to increase the production of better solutions during the search. As a consequence, the ability of the algorithm to escape from local optimum solutions is enhanced. The algorithm is tested through four experiments and its results are compared against two BFOA-based algorithms and also against a differential evolution algorithm designed for mechanical design problems. The overall results indicate that the proposed algorithm outperforms other BFOA-based approaches and finds highly competitive mechanisms, with a single set of parameter values and with less evaluations in the first synthesis problem, with respect to those mechanisms obtained by the differential evolution algorithm, which needed a parameter fine-tuning process for each optimization problem.
[The swimmer's otitis. An up to date and prevention options].
Caramia, G; Serafini, V; Loggi, A
2013-01-01
The swimmer's otitis or acute otitis externa, is a pathology that often occurs in those who practice swimming at a competitive level. The same problem often occurs in the summer with the attendance of swimming pools and bathing areas. A survey made in the United States in 2007 confirms the dynamics of the onset of this pathology, because the contamination of fungi and bacteria in the waters of the swimming pools and the sea cause the inflammation of the epithelium of the auditory canal. To face this issue, in addition to a correct diagnosis, and the necessary and appropriate therapies, it may follow the use of these medicinal preparations. The first one (A) is protective-acting, the second one (B) is characterized as a preventive, hygroscopic, moistening, antiseptic and antimycotic-acting solution. Swimmers who have been using the two (pre-and post) preparations daily for about a year have reported sporadic episodes of otitis. However, there is no doubt that these two compounds deserve a meticulous clinical trial in order to confirm their preventive and therapeutic potentials in external acute otitis.
Pre-Participation Medical Evaluation for Adventure and Wilderness Watersports.
Nathanson, Andrew T; Young, Justin Mark J; Young, Craig
2015-12-01
A request for a preparticipation medical evaluation for wilderness watersports may be made by guiding agencies, instructional camps, or by patients presenting for an annual visit. Although guidelines have been published regarding preparticipation physical evaluation for traditional competitive high school and collegiate sports, little has been written about medical evaluations for those wishing to engage in wilderness and adventure watersports. in this article, we offer guidance based on literature review and expert opinion. Watersports are among the most common recreational activities in the United states and are generally safe. Drowning, however, is a significant risk, particularly in small, self-propelled craft, and among children. Medical counseling before participation in watersports should include screening for medical conditions which may impair swimming ability, including a history of seizures, heart disease, and lung disease. Physicians should also promote preventive health measures such as use of lifejackets and sun protection, as well as alcohol avoidance. Swim testing tailored to specific activities should be strongly considered for children and those with questionable swimming ability. Copyright © 2015. Published by Elsevier Inc.
Gomez-Bruton, Alejandro; Montero-Marín, Jesús; González-Agüero, Alejandro; García-Campayo, Javier; Moreno, Luis A; Casajús, Jose A; Vicente-Rodríguez, Germán
2016-03-01
The effects of swimming on bone mineral density (BMD) have been studied by several researchers, with inconsistent results. This meta-analysis aims to determine whether systematic swimming training may influence BMD during childhood and adolescence. A systematic search was performed in PubMed, SPORTDiscus and ClinicalTrials.gov from the earliest possible year to March 2015, with data extraction and quality assessment performed independently by two researchers following the PRISMA methodology. Swimmers were compared to sedentary controls and to athletes performing highly osteogenic sports. Therefore, a total of two meta-analyses were developed. Fourteen studies met the inclusion criteria and were included in the meta-analyses. Swimmers presented similar BMD values to sedentary controls and lower than other high-impact athletes. Femoral neck and lumbar spine BMD differences between swimmers and sedentary controls and between swimmers and athletes practicing osteogenic sports appeared to increase with age and favored the non-swimming groups. There were no differences by sex. While swimming is associated with several health benefits, it does not appear to be an effective sport for improving BMD. Swimmers might be in need of additional osteogenic exercises for increasing BMD values.
Gourgoulis, Vassilios; Antoniou, Panagiotis; Aggeloussis, Nikolaos; Mavridis, Georgios; Kasimatis, Panagiotis; Vezos, Nikolaos; Boli, Alexia; Mavromatis, Georgios
2010-09-01
The aim of this study was to examine the acute effect of front crawl sprint resisted swimming with different added resistances on the kinematic characteristics of the stroke and the orientation of the hand. Ten female swimmers swam four maximal trials (25 m) with small, moderate, large, and no added resistance respectively. Four camcorders were used to record the underwater motion of the right hand and digitizing was undertaken using the Ariel Performance Analysis System. Stroke rate, the stroke length, and mean swimming velocity were significantly decreased, whereas the total duration of the stroke and the relative duration of the pull and push phases were significantly increased during resisted swimming. The increase in the total duration of the stroke was accompanied by an increase in absolute pull length, while no alterations were observed in relative pull length or medial-lateral displacements of the hand. Moreover, the mean resultant velocity of the hand, as well as the pitch and the sweepback angles of the hand were not modified. In conclusion, resisted swimming appears to be a specific form of training, at least regarding its acute effect, although long-term effects should be investigated further.
Gómez-Bruton, A; Gonzalez-Agüero, A; Casajus, J A; Vicente-Rodriguez, German
2014-08-01
Enviromental factors such as exercise participation and nutrition have often been linked to bone improvements. However, not all sports have the same effects, being non-osteogenic sports such as swimming defined as negative or neutral sports to practice regarding bone mass by some authors, similarly exercise-diet interaction in especific groups is still not clear. To present the methodology of the RENACIMENTO project that aims to evaluate body composition and more specifically bone mass by several techniques in adolescent swimmers and to observe the effects and perdurability of whole body vibration (WBV) and jumping intervention (JIN) on body composition and fitness on this population and explore posible diet interactions. Randomized controlled trial. 78 swimmers (12-17 y) and 26 sex- and age-matched controls will participate in this study. Dual energy X-ray, peripheral Quantitative Computed Tomography, Quantitative Ultrasound, Bioelectrical Impedance Analysis, and anthropometry measurements will be performed in order to evaluate body composition. Physical activity, nutrition, pubertal development and socio-economical status may act as confounders of body composition and therefore will also be registered. Several fitness factors regarding strength, endurance, performance and others will also be registered to evaluate differences with controls and act as confounders. A 7-month WBV therapy will be performed by 26 swimmers consisting of a training of 15 minutes 3 times per week. An 8 month JIM will also be performed by 26 swimmers 3 times per week. The remaining 26 swimmers will continue their normal swimming training. Four evaluations will be performed, the first one in order to describe differences between swimmers and controls. The second one to describe the effects of the interventions and the third and fourth evaluations to describe the perdurability of the effects of the WBV and JIN. The RENACIMIENTO project will allow to answer several questions regarding body composition, fitness, bone mass and interaction with diet of adolescent swimmers, describe swimming as a positive, negative or neutral sport to practice regarding these parameters and elucidate the effects and perdurability of WBV and JIM on body composition. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.
38 CFR 76.3 - Application and certification.
Code of Federal Regulations, 2011 CFR
2011-07-01
... provide certification of the veteran's participation in training or competition sponsored by the USP or... certification must specify whether the payment is due for training, competition, or residence, and the dates of the training, competition, or residence for which payment is due. The Office of Management and Budget...
Effect of swimming suit design on the energy demands of swimming.
Starling, R D; Costill, D L; Trappe, T A; Jozsi, A C; Trappe, S W; Goodpaster, B H
1995-07-01
Eight competitive male swimmers completed a standardized 365.8 m (400 yd) freestyle swimming trial at a fixed pace (approximately 90% of maximal effort) while wearing a torso swim suit (TOR) or a standard racing suit (STD). Oxygen uptake (VO2), blood lactate, heart rate (HR), and distance per stroke (DPS) measurements were obtained. In addition, a video-computer system was used to collect velocity data during a prone underwater glide following a maximal leg push-off from the side of the pool while wearing the TOR and STD suits. These data were used to calculate the total distance covered during the glides. VO2 (3.76 +/- 0.16 vs 3.92 +/- 0.18 l.min-1) and lactate (8.08 +/- 0.53 vs, 9.66 +/- 0.66 mM) were significantly (P < 0.05) lower during the TOR trial than the STD trial. HR was not different (P > 0.05) between the TOR (170.1 +/- 5.1 b.min-1) and STD (173.5 +/- 5.7 b.min-1) trials. DPS was significantly greater during the TOR (2.70 +/- 0.066 m.stroke-1) versus STD (2.58 +/- 0.054 m.stroke-1) trial. A significantly greater total distance was covered during the prone glide while wearing the TOR (2.05 +/- 0.067 m) compared to the STD (2.00 +/- 0.080 m) suit. These findings demonstrate that a specially designed torso suit reduces the energy demand of swimming compared to a standard racing suit which may be due to a reduction in body drag.
Multiple-Transportable Carbohydrate Effect on Long-Distance Triathlon Performance.
Rowlands, David S; Houltham, Stuart D
2017-08-01
The ingestion of multiple (2:1 glucose-fructose) transportable carbohydrate in beverages at high rates (>78 g·h) during endurance exercise enhances exogenous carbohydrate oxidation, fluid absorption, gut comfort, and performance relative to glucose alone. However, during long-distance endurance competition, athletes prefer a solid-gel-drink format, and the effect size of multiple-transportable carbohydrate is unknown. This study aimed to determine the effect of multiple-transportable carbohydrate on triathlon competition performance when ingested within bars, gels, and drinks. A double-blind randomized controlled trial was conducted within two national-body sanctioned half-ironman triathlon races held 3 wk apart in 74 well-trained male triathletes (18-60 yr; >2 yr competition experience). Carbohydrate comprising glucose/maltodextrin-fructose (2:1 ratio) or standard isocaloric carbohydrate (glucose/maltodextrin only) was ingested before (94 g) and during the cycle (2.5 g·km) and run (7.8 g·km) sections, averaging 78.6 ± 6.6 g·h, partitioned to bars (25%), gels (35%), and drink (40%). Postrace, 0- to 10-unit Likert-type scales were completed to assess gut comfort and energy. The trial returned low dropout rate (9%), high compliance, and sensitivity (typical error 2.2%). The effect of multiple-transportable carbohydrate on performance time was -0.53% (95% confidence interval = -1.30% to 0.24%; small benefit threshold = -0.54%), with likelihood-based risk analysis supporting adoption (benefit-harm ratio = 48.9%:0.3%; odds ratio = 285:1). Covariate adjustments for preexercise body weight and heat stress had negligible impact performance. Multiple-transportable carbohydrate possibly lowered nausea during the swim and bike; otherwise, effects on gut comfort and perceived energy were negligible. Multiple-transportable (2:1 maltodextrin/glucose-fructose) compared with single-transportable carbohydrate ingested in differing format provided a small benefit to long-distance triathlon performance, inferred as adoption worthy. Large sample in-competition randomized trials offer ecological validity, high participant throughput, compliance, and sensitivity for evaluation of health and performance interventions in athletes.
Integrated Educational/Leisure Time Model for Deaf-Blind Children and Youth. Final Report.
ERIC Educational Resources Information Center
Thompson, Marie
The report describes the accomplishments of a swimming project to teach instructional objectives to deaf blind, severely-to-profoundly retarded students, using nonhandicapped high school and college students who were trained and paid as peer tutors. Tutors recieved hands-on as well as didactic training and were evaluated by means of pretests and…
NASA Astrophysics Data System (ADS)
Wallace, John M.
Peter Hobbs, a professor in the Department of Atmospheric Sciences at the University of Washington in Seattle, died of pancreatic cancer on 25 July 2005.Born in 1936, Hobbs experienced what he described as “a wild, adventurous youth on the streets of postwar London.” He engaged in competitive swimming and at age 13 held the title of Junior Boxing Champion of the County of Surrey.
Carter, Alecia J; Wilson, Robbie S
2006-12-01
Few studies have examined the adaptive significance of reversible acclimation responses. The aerobic performance and mating behaviour of the sexually coercive male eastern mosquito fish (Gambusia holbrooki) offers an excellent model system for testing the benefits of reversible acclimation responses to mating success. We exposed male mosquito fish to normoxic or hypoxic conditions for 4 weeks and tested their maximum sustained swimming performance and their ability to obtain coercive matings under both normoxic and hypoxic conditions. We predicted that hypoxia-acclimated males would possess greater swimming and mating performance in hypoxic conditions than normoxic-acclimated males, and vice versa when tested in normoxia. Supporting our predictions, we found the sustained swimming performance of male mosquito fish was greater in a hypoxic environment following long-term exposure to low partial pressures of oxygen. However, the benefits of acclimation responses to mating performance were dependent on whether they were tested in the presence or absence of male-male competition. In a non-competitive environment, male mosquito fish acclimated to hypoxic conditions spent a greater amount of time following females and obtained more copulations than normoxic-acclimated males when tested in low partial pressures of oxygen. When males were competed against each other for copulations, we found no influence of long-term exposure to different partial pressures of oxygen on mating behaviour. Thus, despite improvements in the aerobic capacity of male mosquito fish following long-term acclimation to hypoxic conditions, these benefits did not always manifest themselves in improved mating performance. This study represents one of the first experimental tests of the benefits of reversible acclimation responses, and indicates that the ecological significance of physiological plasticity may be more complicated than previously imagined.
Relationships between training load, injury, and fitness in sub-elite collision sport athletes.
Gabbett, Tim J; Domrow, Nathan
2007-11-01
The purpose of this study was to develop statistical models that estimate the influence of training load on training injury and physical fitness in collision sport athletes. The incidence of training injuries was studied in 183 rugby league players over two competitive seasons. Participants were assessed for height, body mass, skinfold thickness, vertical jump, 10-m, 20-m and 40-m sprint time, agility, and estimated maximal aerobic power in the off-season, pre-season, mid-season, and end-season. Training load and injury data were summarised into pre-season, early-competition, and late-competition training phases. Individual training load, fitness, and injury data were modelled using a logistic regression model with a binomial distribution and logit link function, while team training load and injury data were modelled using a linear regression model. While physical fitness improved with training, there was no association (P=0.16-0.99) between training load and changes in physical fitness during any of the training phases. However, increases in training load during the early-competition training phase decreased (P= 0.04) agility performance. A relationship (P= 0.01-0.04) was observed between the log of training load and odds of injury during each training phase, resulting in a 1.50 - 2.85 increase in the odds of injury for each arbitrary unit increase in training load. Furthermore, during the pre-season training phase there was a relationship (P= 0.01) between training load and injury incidence within the training load range of 155 and 590 arbitrary units. During the early and late-competition training phases, increases in training load of 175-620 arbitrary units and 145-410 arbitrary units, respectively, resulted in no further increase in injury incidence. These findings demonstrate that increases in training load, particularly during the pre-season training phase, increase the odds of injury in collision sport athletes. However, while increases in training load from 175 to 620 arbitrary units during the early-competition training phase result in no further increase in injury incidence, marked reductions in agility performances can occur. These findings suggest that reductions in training load during the early-competition training phase can reduce the odds of injury without compromising agility performances in collision sport athletes.
Swim and Survival at Sea Training: Does It Meet the Navy’s Needs
1989-06-01
34minimum water survival qualification for service in the Navy" [Ref. 2]. One can infer that, due to the nature of the job and its environment. Naval...they will receive dai !A Y im inctract to until they qual ifl. How lori 8 can oAAC of these individuals remain in swim hold status? The RTC’s are...occurred whilo victims were on duty. resulting in 43 drowni r[.ef. f Fighty of these mishapr involved personrvol Wh, ci t lor intentional ly jumped from
Knechtle, Beat; Nikolaidis, Pantelis T; Rosemann, Thomas; Rüst, Christoph A
2016-06-22
Every year, thousands of triathletes try to qualify for the «Ironman Hawaii» (3,8 km swimming, 180 km cycling and 42,195 km running), the World Championship of long-distance triathletes. In this overview, we present the recent findings in literature with the most important variables with an influence on Ironman triathlon performance. The most important performance-influencing factors for a fast Ironman race time for both women and men are a large training volume and a high intensity in training, a large volume being more important than a high intensity, a low percentage of body fat, an ideal age of 30–35 years, a fast personal best in the Olympic distance triathlon (1,5 km swimming, 40 km cycling and 10 km running), a fast personal best in marathon running and origin from the United States of America.
Ribeiro, R A; Bonfleur, M L; Vanzela, E C; Zotti, A I; Scomparin, D X; Boschero, A C; Balbo, S L
2014-08-01
Physical exercise represents an alternative way to prevent and/or ameliorate chronic metabolic diseases. Disruption of sympathetic nervous system (SNS) activity contributes to adiposity in obese subjects. Here, we verified the preventive effect of swimming training upon adiposity, adrenal catecholamine storage, and pancreatic islet function in obese monosodium glutamate (MSG)-treated rats. Male neonatal Wistar rats received MSG (4 mg/g body weight) during the first 5 days of life and, at weaning, half of the rats were submitted to swimming training, 30 min/day, 3 days a week, until 90 days of age (exercised rats: MSGex). Half of the rats were used as controls (sedentary group, MSGsd). Exercise training (ET) decreased insulinemia and fat deposition in MSGex, and increased adrenal catecholamine content, compared with MSGsd rats. Insulinemia during the ivGTT was lower in MSGex rats, despite a lack of difference in glycemia. Swimming training enhanced insulin release in islets challenged by 2.8-8.3 mmol/l glucose, whereas, at supraphysiological glucose concentrations (11.1-16.7 mmol/l), MSGex islets secreted less insulin than MSGsd. No differences in insulin secretion were observed following l-arginine (Arg) or K(+) stimuli. In contrast, islets from MSGex rats secreted more insulin when exposed to carbachol (100 μmol/l), forskolin (10 μmol/l), or IBMX (1 mmol/l) at 8.3 mmol/l glucose. Additionally, MSGex islets presented a better epinephrine inhibition upon insulin release. These results demonstrate that ET prevented the onset of obesity in MSG rats, probably by enhancing adrenal catecholamine levels. ET ameliorates islet responsiveness to several compounds, as well as insulin peripheral action. © Georg Thieme Verlag KG Stuttgart · New York.
Guaraldo, Simone A; Serra, Andrey Jorge; Amadio, Eliane Martins; Antônio, Ednei Luis; Silva, Flávio; Portes, Leslie Andrews; Tucci, Paulo José Ferreira; Leal-Junior, Ernesto Cesar Pinto; de Carvalho, Paulo de Tarso Camillo
2016-07-01
The aim of the present study was to determine whether low-level laser therapy (LLLT) in conjunction with aerobic training interferes with oxidative stress, thereby influencing the performance of old rats participating in swimming. Thirty Wistar rats (Norvegicus albinus) (24 aged and six young) were tested. The older animals were randomly divided into aged-control, aged-exercise, aged-LLLT, aged-LLLT/exercise, and young-control. Aerobic capacity (VO2max(0.75)) was analyzed before and after the training period. The exercise groups were trained for 6 weeks, and the LLLT was applied at 808 nm and 4 J energy. The rats were euthanized, and muscle tissue was collected to analyze the index of lipid peroxidation thiobarbituric acid reactive substances (TBARS), glutathione (GSH), superoxide dismutase (SOD), and catalase (CAT) activities. VO2 (0.75)max values in the aged-LLLT/exercise group were significantly higher from those in the baseline older group (p <0.01) and the LLLT and exercise group (p <0.05). The results indicate that the activities of CAT, SOD, and GPx were higher and statistically significant (p <0.05) in the LLLT/exercise group than those in the LLLT and exercise groups. Young animals presented lesser and statistically significant activities of antioxidant enzymes compared to the aged group. The LLLT/exercise group and the LLLT and exercise group could also mitigate the concentration of TBARS (p > 0.05). Laser therapy in conjunction with aerobic training may reduce oxidative stress, as well as increase VO2 (0.75)max, indicating that an aerobic exercise such as swimming increases speed and improves performance in aged animals treated with LLLT.
Frenkl, R; Györe, A
1979-01-01
In Experiment 1 a double-phase test diet (high-protein low-carbohydrate phase (HP): 5 days, high-carbohydrate phase (HC): 2 days) was compared to a normal diet by measuring all-out performance in rats trained by steady or interval swimming exercise. The tests carried out on the 8th day showed the swimming performance to be improved to a similar extent by the two training procedures, to be further improved by the test diet in the exercised animals; changes in liver glycogen, blood glucose and serum corticosterone reflected especially in the influence of exercise which in some cases was potentiated by the test diet. In Experiment 2 the 5 days of high protein intake were treated separately from the effect of the double-phase test diet as a whole in order to study the mechanism. These aminals were exercised by treadmill running of 7 days. Cytochrome P450 content of the liver rose under the effect of exercise as well as the HP phase, thus supplying additional evidence for the enzyme inducer effect of physical exertion. Glycogen decreased both in the muscle and liver during the HP phase and returned to normal after the HC phase. Liver glycogen rose to an even higher level than normal in the trained groups, but muscle glycogen values remained lower, this may be related to the shortness of training and to an accelerated rate of turnover. High protein intake associated with a depletion of carbohydrate stores was found to have an effect of its own which, when followed by replenishment of calories reserves, might be used to advantage in improving physical performance.
Drag, but not buoyancy, affects swim speed in captive Steller sea lions
Suzuki, Ippei; Sato, Katsufumi; Fahlman, Andreas; Naito, Yasuhiko; Miyazaki, Nobuyuki; Trites, Andrew W.
2014-01-01
ABSTRACT Swimming at an optimal speed is critical for breath-hold divers seeking to maximize the time they can spend foraging underwater. Theoretical studies have predicted that the optimal swim speed for an animal while transiting to and from depth is independent of buoyancy, but is dependent on drag and metabolic rate. However, this prediction has never been experimentally tested. Our study assessed the effects of buoyancy and drag on the swim speed of three captive Steller sea lions (Eumetopias jubatus) that made 186 dives. Our study animals were trained to dive to feed at fixed depths (10–50 m) under artificially controlled buoyancy and drag conditions. Buoyancy and drag were manipulated using a pair of polyvinyl chloride (PVC) tubes attached to harnesses worn by the sea lions, and buoyancy conditions were designed to fall within the natural range of wild animals (∼12–26% subcutaneous fat). Drag conditions were changed with and without the PVC tubes, and swim speeds were recorded and compared during descent and ascent phases using an accelerometer attached to the harnesses. Generalized linear mixed-effect models with the animal as the random variable and five explanatory variables (body mass, buoyancy, dive depth, dive phase, and drag) showed that swim speed was best predicted by two variables, drag and dive phase (AIC = −139). Consistent with a previous theoretical prediction, the results of our study suggest that the optimal swim speed of Steller sea lions is a function of drag, and is independent of dive depth and buoyancy. PMID:24771620
[Comparing the young asthmatics running fitness].
Belányi, Kinga; Gyene, István; Bak, Zsuzsa; Mezei, Györgyi
2007-02-25
Nowadays, doctors strongly recommend physical activity for asthmatic children, since the resulting improved physical fitness and psychological change also raise the quality of life. The aim of this study was to compare the physical fitness of asthmatic children who regularly participate in therapeutic swimming, with asthmatic children who do not participate in this training and with non-swimming, healthy children using the 12 minute free running, Cooper test. The children from the swimmer asthmatic group (n= 51, age = 9-22 yrs) took part in a special, long term, swimming exercise program (Gyene method). Whereas, the non-swimmer asthmatics (n = 28, age = 8-22 yrs) and the healthy children (n: 179, age: 9-22 yrs) only took part in the normal school physical education classes. Fitness was measured using the Cooper test. Data was collected from 258 subjects and showed that the fitness of swimmer asthmatics is significantly better than that of the non-swimmer asthmatics and even better than that of the healthy subjects (swimmer/ non swimmer asthmatic p = 0.01; swimmer asthmatic/ healthy p < 0.0001 Chi(2) test). The difference in the fitness acquired from swimming was the most pronounced for the 8-11 years old asthmatics, presumably because of greater motivational factors. No differences were found between genders for the two asthmatic groups, whereas healthy boys were found to have significantly greater levels of fitness than healthy girls. Fitness is substantially increased with regular swimming. The favourable effects of swimming are expressed not only in comparison with the non-swimmer asthmatics but with the healthy subjects too. The regular therapeutic swimming program helps the formation of running fitness too.
Laporte, Martin; Dalziel, Anne C; Martin, Nicolas; Bernatchez, Louis
2016-08-11
Improved performance in a given ecological niche can occur through local adaptation, phenotypic plasticity, or a combination of these mechanisms. Evaluating the relative importance of these two mechanisms is needed to better understand the cause of intra specific polymorphism. In this study, we reared populations of Lake Whitefish (Coregonus clupeaformis) representing the'normal' (benthic form) and the 'dwarf' (derived limnetic form) ecotypes in two different conditions (control and swim-training) to test the relative importance of adaptation and acclimation in the differentiation of traits related to swimming capacity. The dwarf whitefish is a more active swimmer than the normal ecotype, and also has a higher capacity for aerobic energy production in the swimming musculature. We hypothesized that dwarf fish would show changes in morphological and physiological traits consistent with reductions in the energetic costs of swimming and maintenance metabolism. We found differences in traits predicted to decrease the costs of prolonged swimming and standard metabolic rate and allow for a more active lifestyle in dwarf whitefish. Dwarf whitefish evolved a more streamlined body shape, predicted to lead to a decreased drag, and a smaller brain, which may decrease their standard metabolic rate. Contrary to predictions, we also found evidence of acclimation in liver size and metabolic enzyme activities. Results support the view that local adaptation has contributed to the genetically-based divergence of traits associated with swimming activity. Presence of post-zygotic barriers limiting gene flow between these ecotype pairs may have favoured repeated local adaptation to the limnetic niches.
Prescribed and self-reported seasonal training of distance runners.
Hewson, D J; Hopkins, W G
1995-12-01
A survey of 123 distance-running coaches and their best runners was undertaken to describe prescribed seasonal training and its relationship to the performance and self-reported training of the runners. The runners were 43 females and 80 males, aged 24 +/- 8 years (mean +/- S.D.), training for events from 800 m to the marathon, with seasonal best paces of 86 +/- 6% of sex- and age-group world records. The coaches and runners completed a questionnaire on typical weekly volumes of interval and strength training, and typical weekly volumes and paces of moderate and hard continuous running, for build-up, pre-competition, competition and post-competition phases of a season. Prescribed training decreased in volume and increased in intensity from the build-up through to the competition phase, and had similarities with 'long slow distance' training. Coaches of the faster runners prescribed longer build-ups, greater volumes of moderate continuous running and slower relative paces of continuous running (r = 0.19-0.36, P < 0.05), suggesting beneficial effects of not training close to competition pace. The mean training volumes and paces prescribed by the coaches were similar to those reported by the runners, but the correlations between prescribed and reported training were poor (r = 0.2-0.6). Coaches may therefore need to monitor their runners' training more closely.
BIOCHEMICAL ANALYSIS AND BONE REMODELING IN RESPONSE TO OOPHORECTOMY AND AQUATIC TRAINING
SOUZA, HELENA RIBEIRO; GIROL, ANA PAULA; SCHIAVETO, ADRIANA PAULA SANCHEZ; GEROMEL, MAIRTO ROBERIS; IYOMASA, MELINA MIZUSAKI; ARRUDA, MAURÍCIO FERRAZ DE
2016-01-01
ABSTRACT Objective: To investigate whether swimming could prevent bone loss and could be indicated to assist in treatment of osteoporosis. Methods: Female rats were divided into 4 groups (n=6), two of them were oophorectomized. Animals from two groups, one oophorectomized and another not oophorectomized, underwent aquatic training for eight weeks. After training, the animals were sacrificed and their blood was collected for calcium and alkaline phosphatase serum dosage; the femur was removed and subjected to radiological and histological densitometry analysis to assess bone loss and osteoclast counting on femoral head and neck. Results: Increase in serum calcium was not observed. There was an increasing activity of alkaline phosphatase in the oophorectomized groups. The radiographs suggest that there was a greater bone mass density in the trained groups. Concerning histology, the trained groups had better tissue structural organization than the sedentary groups. In the oophorectomized and sedentary group, higher presence of osteoclasts was observed a. Conclusion: Exercise and oophorectomy did not promote changes in serum calcium levels. The decrease of sex steroids caused by oophorectomy was responsible for severe bone loss, but swimming exercise was able to reduce this loss. Oophorectomy promoted the proliferation of osteoclasts and the exercise proved to be able to diminish it. Level of Evidence I, Experimental Study. PMID:28149187
Salivary Hormones Response to Preparation and Pre-competitive Training of World-class Level Athletes
Guilhem, Gaël; Hanon, Christine; Gendreau, Nicolas; Bonneau, Dominique; Guével, Arnaud; Chennaoui, Mounir
2015-01-01
This study aimed to compare the response of salivary hormones of track and field athletes induced by preparation and pre-competitive training periods in an attempt to comment on the physiological effects consistent with the responses of each of the proteins measured. Salivary testosterone, cortisol, alpha-amylase, immunoglobulin A (IgA), chromogranin A, blood creatine kinase activity, and profile of mood state were assessed at rest in 24 world-class level athletes during preparation (3 times in 3 months) and pre-competitive (5 times in 5 weeks) training periods. Total mood disturbance and fatigue perception were reduced, while IgA (+61%) and creatine kinase activity (+43%) increased, and chromogranin A decreased (−27%) during pre-competitive compared to preparation period. A significant increase in salivary testosterone (+9 to +15%) and a decrease in testosterone/cortisol ratio were associated with a progressive reduction in training load during pre-competitive period (P < 0.05). None of the psycho-physiological parameters were significantly correlated to training load during the pre-competitive period. Results showed a lower adrenocortical response and autonomic activity, and an improvement of immunity status, in response to the reduction in training load and fatigue, without significant correlations of salivary hormones with training load. Our findings suggest that saliva composition is sensitive to training contents (season period) but could not be related to workload resulting from track and field athletics training. PMID:26635619
McCreery, Greig L; El-Beheiry, Mostafa; Schlachta, Christopher M
2017-11-01
Dedicated practice using laparoscopic simulators improves operative performance. Yet, voluntary utilization is minimal. We hypothesized that skill competition between peers, at the local and national level, positively influences residents' use of laparoscopic simulators. A web-based survey evaluated the relationship between Canadian General Surgery residents' use of laparoscopic simulation and participation in competition. Secondary outcomes assessed attitudes regarding simulation training, factors limiting use, and associations between competition level and usage. One hundred ninety (23%) of 826 potential participants responded. Eighty-three percent rated their laparoscopic abilities as novice or intermediate. More than 70% agreed that use of simulation practice improves intra-operative performance, and should be a mandatory component of training. However, 58% employed simulator practice less than once per month, and 18% never used a simulator. Sixty-five percent engaged in simulator training for 5 h or less over the preceding 6 months. Seventy-three percent had participated in laparoscopic skill competition. Of those, 51% agreed that competition was a motivation for simulation practice. No association was found between those with competition experience and simulator use. However, 83% of those who had competed nationally reported >5 h of simulator use in the previous 6 months compared to those with no competition experience (26%), local competition (40%), and local national-qualifying competition (23%) (p < 0.001). This study does not support the hypothesis that competition alone universally increases voluntary use of simulation-based training, with only the minority of individuals competing at the national level demonstrated significantly higher simulation use. However, simulation training was perceived as a valuable exercise. Lack of time and access to simulators, as opposed to lack of interest, were the most commonly reported to limited use.
Burgos, Juan I; Yeves, Alejandra M; Barrena, Jorge P; Portiansky, Enrique L; Vila-Petroff, Martín G; Ennis, Irene L
2017-11-01
Cardiac adaptation to endurance training includes improved contractility by a non-yet clarified mechanism. Since IGF-1 is the main mediator of the physiological response to exercise, we explored its effect on cardiac contractility and the putative involvement of nitric oxide (NO) and CaMKII in control and swim-trained mice. IGF-1 increased cardiomyocyte shortening (128.1±4.6% vs. basal; p˂0.05) and accelerated relaxation (time to 50% relengthening: 49.2±2.0% vs. basal; p˂0.05), effects abrogated by inhibition of: AKT with MK-2206, NO production with the NO synthase (NOS) inhibitor L-NAME and the specific NOS1 inhibitor nitroguanidine (NG), and CaMKII with KN-93. In agreement, an increase in NO in response to IGF-1 (133.8±2.2%) was detected and prevented by both L-NAME and NG but not KN-93, suggesting that CaMKII activation was downstream NO. In addition, we determined CaMKII activity (P-CaMKII) and phosphorylation of its target, Thr17-PLN. IGF-1, by a NO-dependent mechanism, significantly increased both (227.2±29.4% and 145.3±5.4%, respectively) while no changes in the CaMKII phosphorylation site of ryanodine receptor were evident. The improvement in contractility induced by IGF-1 was associated with increased Ca 2+ transient amplitude, rate of decay and SR content. Interestingly, this response was absent in cardiomyocytes from transgenic mice that express a CaMKII inhibitory peptide (AC3-I strain). Moreover, AC3-I mice subjected to swim training did develop physiological cardiac hypertrophy but not the contractile adaptation. Therefore, we conclude that NO-dependent CaMKII activation plays a critical role in the improvement in contractility induced by IGF-1 and exercise training. Interestingly, this pathway would not contribute to the adaptive hypertrophy. Copyright © 2017 Elsevier Ltd. All rights reserved.
Huang, Chi-Chang; Wang, Ting; Tung, Yu-Tang; Lin, Wan-Teng
2016-01-01
The protein deacetylase sirtuin 1 (SIRT1) and activate peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) pathway drives the muscular fiber-type switching, and can directly regulate the biophysiological functions of skeletal muscle. To investigate whether 12-week swimming exercise training modulates the SIRT1/PGC-1α pathway associated proteins expression in rats of different age. Male 3-month-old (3M), 12-month-old (12M) and 18-month-old (18M) Sprague-Dawley rats were used and assigned to sedentary control (C) or 12-week swimming exercise training (E) and divided into six groups: 3MC (n = 8), 12MC (n = 6), 18MC (n = 8), 3ME (n = 8), 12ME (n = 5) and 18ME (n = 6). Body weight, muscle weight, epididymal fat mass and muscle morphology were performed at the end of the experiment. The protein levels of SIRT1, PGC-1α, AMPK and FOXO3a in the gastrocnemius and soleus muscles were examined. The SIRT1, PGC-1α and AMPK levels in the gastrocnemius and soleus muscles were up-regulated in the three exercise training groups than three control groups. The FOXO3a level in the 12ME group significantly increased in the gastrocnemius muscles than 12MC group, but significantly decreased in the soleus muscles. In 3-, 12- and 18-month-old rats with and without exercise, there was a significant main effect of exercise on PGC-1α, AMPK and FOXO3a in the gastrocnemius muscles, and SIRT1, PGC-1α and AMPK in the soleus muscles. Our result suggests that swimming training can regulate the SIRT1/PGC-1α, AMPK and FOXO3a proteins expression of the soleus muscles in aged rats. PMID:27076782
Knechtle, Beat; Zingg, Matthias Alexander; Rosemann, Thomas; Stiefel, Michael; Rüst, Christoph Alexander
2015-01-01
Objective This narrative review summarizes recent intentions to find potential predictor variables for ultra-triathlon race performance (ie, triathlon races longer than the Ironman distance covering 3.8 km swimming, 180 km cycling, and 42.195 km running). Results from studies on ultra-triathletes were compared to results on studies on Ironman triathletes. Methods A literature search was performed in PubMed using the terms “ultra”, “triathlon”, and “performance” for the aspects of “ultra-triathlon”, and “Ironman”, “triathlon”, and “performance” for the aspects of “Ironman triathlon”. All resulting papers were searched for related citations. Results for ultra-triathlons were compared to results for Ironman-distance triathlons to find potential differences. Results Athletes competing in Ironman and ultra-triathlon differed in anthropometric and training characteristics, where both Ironmen and ultra-triathletes profited from low body fat, but ultra-triathletes relied more on training volume, whereas speed during training was related to Ironman race time. The most important predictive variables for a fast race time in an ultra-triathlon from Double Iron (ie, 7.6 km swimming, 360 km cycling, and 84.4 km running) and longer were male sex, low body fat, age of 35–40 years, extensive previous experience, a fast time in cycling and running but not in swimming, and origins in Central Europe. Conclusion Any athlete intending to compete in an ultra-triathlon should be aware that low body fat and high training volumes are highly predictive for overall race time. Little is known about the physiological characteristics of these athletes and about female ultra-triathletes. Future studies need to investigate anthropometric and training characteristics of female ultra-triathletes and what motivates women to compete in these races. Future studies need to correlate physiological characteristics such as maximum oxygen uptake (VO2max) with ultra-triathlon race performance in order to investigate whether these characteristics are also predictive for ultra-triathlon race performance. PMID:26056498
Salivary Biomarkers and Training Load during Training and Competition in Paralympic Swimmers.
Sinnott-O'Connor, Ciara; Comyns, Tom; Nevill, Alan M; Warrington, Giles
2017-11-28
Stress responses in athletes can be attributed to training and also competition, where increased physiological and psychological stress may negatively impact on performance and recovery. The aim of this study was to examine the relationship between training load and salivary biomarkers IgA, alpha-amylase (AA) and cortisol across a 16-week preparation phase and 10-day competition phase in Paralympic swimmers. Four Paralympic swimmers provided bi-weekly saliva samples during three training phases - 1) normal training, 2) intensified training and 3) taper as well as daily saliva samples in the 10 day Paralympic competition (2016 Paralympic Games). Training load (TL) was measured using session-RPE. Multi-level analysis identified a significant increase in sIgA (94.98 (27.69) μg.ml -1 ), sAA (45.78 (19.07) μg.ml -1 ) and salivary cortisol (7.92 (2.17) ng.ml) during intensified training concurrent with a 38.3% increase in TL. During taper phase, a 49.5% decrease in TL from the intensified training phase resulted in decrease in sIgA, sAA and salivary cortisol; however, all three remained higher than baseline levels. A further significant increase was observed during competition in sIgA (168.69(24.19) μg.ml -1 ), sAA (35.86(16.67) μg.ml -1 ) and salivary cortisol (10.49(1.89) ng.ml) despite a continued decrease (77.8%) in TL from taper phase. Results demonstrate performance in major competition such as Paralympic Games despite a noticeable reduction in TL induces a stress response in athletes. Due to elevated stress response observed, modifications to individual post-race recovery protocols may be required to enable athletes to maximise performance across all ten days of competition.
Effect of Beetroot Juice Supplementation on Aerobic Response during Swimming
Pinna, Marco; Roberto, Silvana; Milia, Raffaele; Marongiu, Elisabetta; Olla, Sergio; Loi, Andrea; Migliaccio, Gian Mario; Padulo, Johnny; Orlandi, Carmine; Tocco, Filippo; Concu, Alberto; Crisafulli, Antonio
2014-01-01
The beneficial effects of beetroot juice supplementation (BJS) have been tested during cycling, walking, and running. The purpose of the present study was to investigate whether BJS can also improve performance in swimmers. Fourteen moderately trained male master swimmers were recruited and underwent two incremental swimming tests randomly assigned in a pool during which workload, oxygen uptake (VO2), carbon dioxide production (VCO2), pulmonary ventilation (VE), and aerobic energy cost (AEC) of swimming were measured. One was a control swimming test (CSW) and the other a swimming test after six days of BJS (0.5l/day organic beetroot juice containing about 5.5 mmol of NO3−). Results show that workload at anaerobic threshold was significantly increased by BJS as compared to the CSW test (6.3 ± 1 and 6.7 ± 1.1 kg during the CSW and the BJS test respectively). Moreover, AEC was significantly reduced during the BJS test (1.9 ± 0.5 during the SW test vs. 1.7 ± 0.3 kcal·kg−1·h−1 during the BJS test). The other variables lacked a statistically significant effect with BJS. The present investigation provides evidence that BJS positively affects performance of swimmers as it reduces the AEC and increases the workload at anaerobic threshold. PMID:24481133
Effect of beetroot juice supplementation on aerobic response during swimming.
Pinna, Marco; Roberto, Silvana; Milia, Raffaele; Marongiu, Elisabetta; Olla, Sergio; Loi, Andrea; Migliaccio, Gian Mario; Padulo, Johnny; Orlandi, Carmine; Tocco, Filippo; Concu, Alberto; Crisafulli, Antonio
2014-01-29
The beneficial effects of beetroot juice supplementation (BJS) have been tested during cycling, walking, and running. The purpose of the present study was to investigate whether BJS can also improve performance in swimmers. Fourteen moderately trained male master swimmers were recruited and underwent two incremental swimming tests randomly assigned in a pool during which workload, oxygen uptake (VO₂), carbon dioxide production (VCO₂), pulmonary ventilation (VE), and aerobic energy cost (AEC) of swimming were measured. One was a control swimming test (CSW) and the other a swimming test after six days of BJS (0.5 l/day organic beetroot juice containing about 5.5 mmol of NO₃⁻). Results show that workload at anaerobic threshold was significantly increased by BJS as compared to the CSW test (6.3 ± 1 and 6.7 ± 1.1 kg during the CSW and the BJS test respectively). Moreover, AEC was significantly reduced during the BJS test (1.9 ± 0.5 during the SW test vs. 1.7 ± 0.3 kcal·kg⁻¹1·h⁻¹ during the BJS test). The other variables lacked a statistically significant effect with BJS. The present investigation provides evidence that BJS positively affects performance of swimmers as it reduces the AEC and increases the workload at anaerobic threshold.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Palabrica, R.J.
1981-01-01
The Philippines has a 1-MW swimming-pool reactor facility operated by the Philippine Atomic Energy Commission (PAEC). The reactor is light-water moderated and cooled, graphite reflected, and fueled with 90% enriched uranium. Since it became critical in 1963 it has been utilized for research, radioisotope production, and training. It was used initially in the training of PAEC personnel and other research institutions and universities. During the last few years, however, it has played a key role in training personnel for the Philippine Nuclear Power Project (PNPP).
Rejman, Marek; Wiesner, Wojciech; Silakiewicz, Piotr; Klarowicz, Andrzej; Abraldes, J. Arturo
2012-01-01
The aim of this study was an analysis of the time required to swim to a victim and tow them back to shore, while perfoming the flutter-kick and the dolphin-kick using fins. It has been hypothesized that using fins while using the dolphin-kick when swimming leads to reduced rescue time. Sixteen lifeguards took part in the study. The main tasks performed by them, were to approach and tow (double armpit) a dummy a distance of 50m while applying either the flutter-kick, or the dolphin-kick with fins. The analysis of the temporal parameters of both techniques of kicking demonstrates that, during the approach to the victim, neither the dolphin (tmean = 32.9s) or the flutter kick (tmean = 33.0s) were significantly faster than the other. However, when used for towing a victim the flutter kick (tmean = 47.1s) was significantly faster when compared to the dolphin-kick (tmean = 52.8s). An assessment of the level of technical skills in competitive swimming, and in approaching and towing the victim, were also conducted. Towing time was significantly correlated with the parameter that linked the temporal and technical dimensions of towing and swimming (difference between flutter kick towing time and dolphin-kick towing time, 100m medley time and the four swimming strokes evaluation). No similar interdependency has been discovered in flutter kick towing time. These findings suggest that the dolphin-kick is a more difficult skill to perform when towing the victim than the flutter-kick. Since the hypothesis stated was not confirmed, postulates were formulated on how to improve dolphin-kick technique with fins, in order to reduce swimming rescue time. Key points The source of reduction of swimming rescue time was researched. Time required to approach and to tow the victim while doing the flutter kick and the dolphin-kick with fins was analyzed. The propulsion generated by dolphin-kick did not make the approach and tow faster than the flutter kick. More difficult skill to realize of dolphin-kick than the flutter-kick was postulated. The criteria for how improve dolphin kick technique with fins were formulated. PMID:24150079
Shirali, Saeed; Barari, Alireza; Hosseini, Seyed Ahmad; Khodadi, Elaheh
2017-01-01
The aim of this study was to determine effects of six weeks endurance training and Aloe Vera supplementation on COX-2 and VEGF levels in mice with breast cancer. For this purpose, 35 rats were randomly divided into 5 groups: control (healthy) and 4 cancer groups: control (cancer only), training, Aloe Vera and Aloe Vera + training. Breast cancer tumors were generated in mice by implantind. The training program comprised six weeks of swimming training accomplished in three sessions per week. Training time started with 10 minutes on the first day and increased to 60 minutes in the second week and the water flow rate was increased from 7 to 15 liters per minute at a constant rate. Aloe Vera extract at a dose of 300 mg/kg BW was administrated to rats by intraperitoneal injection. At the end of the study period, rats were anesthetized and blood samples were taken. Significant differences were concluded at p<0.05 with Kolmogorov-Smirnov and Tukey tests to analyze the data. The results showed significant increase in levels of serum. COX-2 and VEGF levels in the cancer group compared with the healthy group. Administration of Aloe Vera extract caused significant decrease in the COX-2 level in the cancer group. Also, in the training (swimming exercise) and Aloe Vera + training cancer groups, we observed significant decrease in the VEGF level as compared to controls. Our results suggest that Aloe Vera and training inhibit the COX pathway and cause decrease production of prostaglandin E2. Hence administration of Aloe Vera in combination with endurance training might synergistically improve the host milieu in mice bearing breast cancers. Creative Commons Attribution License
Prostate Cancer Research Training Program
2011-05-01
and the University of Iowa. These include exercise facilities (running, tennis, basketball, volleyball, handball /racquetball, weights, biking, and...swimming), local beaches , and museums (art, natural history, and sports). In addition, there are a large number of restaurants ranging from fast
... is the use of anabolic steroids or other performance-enhancing drugs and preparations that supposedly help muscles develop. Steroid use is widespread in many sports — including football, swimming, biking, track and field, and baseball. But because many of their long-term effects ...
Hashimoto, Daniel A.; Gomez, Ernest D.; Beyer-Berjot, Laura; Khajuria, Ankur; Williams, Noel N.; Darzi, Ara; Aggarwal, Rajesh
2015-01-01
Background Serious games have demonstrated efficacy in improving participation in surgical training activities, but studies have not yet demonstrated the effect of serious gaming on performance. This study investigated whether competitive training affects laparoscopic surgical performance. Methods Twenty novices were recruited, and 18 (2 drop-outs) were randomized into control or competitive (CT) groups to perform 10 virtual reality (VR) laparoscopic cholecystectomies (LC). Competitiveness of each participant was assessed. The CT group was informed they were competing to outperform one another for a prize; performance ranking was shown prior to each session. The control group did not compete. Performance was assessed on time, movements, and instrument path length. Quality of performance was assessed with a global rating score (GRS). Results There were no significant intergroup differences in baseline skill or measured competitiveness. Time and GRS, at final LC, were not significantly different between groups; however, the CT group was significantly more dexterous than control and had significantly lower variance in number of movements and instrument path length at the final LC (p=0.019). Contentiousness was inversely related to time in the CT group. Conclusion This was the first randomized controlled trial to investigate if competitive training can enhance performance in laparoscopic surgery. Competitive training may lead to improved dexterity in laparoscopic surgery but yields otherwise similar performance to standard training in novices. Competition may have different effects on novices versus experienced surgeons, and subsequent research should investigate competitive training in experienced surgeons as well. PMID:26169566
Analysis of sports injuries related with shooting.
Kabak, Banu; Karanfilci, Muharrem; Ersöz, Taner; Kabak, Mehmet
2016-06-01
Athletes typically maintain rigorous training and work programs to be able to participate in competitions. An injury that occurs during the competition that causes withdrawal from the competition and a possible departure from sports, can render results athletes' and their support staff's efforts as meaningless. The early detection of injuries in the competition and developing preventive training programs can help ensure that participating in competitions and the associated preparatory efforts are not wasted. In this study, the sports injuries discussed occurred during training and competition events of the Turkish Shooting Sportive group. Body parts of injuries are determined and exercise programs focused on the affected body parts are developed. A total of 729 athletes (285 female, 444 male) who participated in Turkish Shooting Sports Championship during the 2010-2011 competition period participated in the study. Athletes were given a questionnaire that was developed prior to the event, and the questionnaire was filled in during interviews conducted one-on-one. Data was collected from the questionnaire and SPSS v.16.0 was used to analyze the results. The study was completed in six months. The results showed that the most of the injuries that occurred during training were strain and muscle tears whereas most of the injuries occurred during the actual competition were strain, muscle tears, tendinitis, and sprain. The results also indicated that during training, the most frequently-occurring injuries were in shoulder, calf-thigh, hand and wrist; whereas during the competition, it was manifested in the shoulder, foot and ankle. Muscle strengthening, stretching and proprioception exercises for these body parts should be included as part of the athletic training program.
Binayi, Fateme; Joukar, Siyavash; Najafipour, Hamid; Karimi, Abdolah; Karimi, Ali; Abdollahi, Farzane; Masumi, Yaser
2016-01-01
We examined the influence of chronic administration of nandrolone decanoate with low-intensity endurance swimming exercise on susceptibility to lethal ventricular arrhythmias in rat. The animal groups included the control group, exercise group (EX), nandrolone group (Nan), vehicle group (Arach), trained vehicle group (Arach + Ex) and trained nandrolone group (Nan + Ex) that treated for 8 weeks. Then, arrhythmia induction was performed by intravenous infusion of aconitine and electrocardiogram recorded. Then, malondialdehyde (MDA), hydroxyproline (HYP) and glutathione peroxidase of heart tissue were measured. Chronic administration of nandrolone with low-intensity endurance swimming exercise had no significant effect on blood pressure, heart rate and basal ECG parameters except RR interval that showed increase (P < 0.05). Low-intensity exercise could prevent the incremental effect of nandrolone on MDA and HYP significantly. It also increased the heart hypertrophy index (P < 0.05) and reduced the abating effect of nandrolone on animal weighting. Nandrolone along with exercise significantly increased the duration of VF (P < 0.05) and reduced the VF latency (P < 0.05). The findings suggest that chronic co-administration of nandrolone with low-intensity endurance swimming exercise to some extent facilitates the occurrence of ventricular fibrillation in rat. Complementary studies are needed to elucidate the involved mechanisms of this abnormality.
Efficient k-Winner-Take-All Competitive Learning Hardware Architecture for On-Chip Learning
Ou, Chien-Min; Li, Hui-Ya; Hwang, Wen-Jyi
2012-01-01
A novel k-winners-take-all (k-WTA) competitive learning (CL) hardware architecture is presented for on-chip learning in this paper. The architecture is based on an efficient pipeline allowing k-WTA competition processes associated with different training vectors to be performed concurrently. The pipeline architecture employs a novel codeword swapping scheme so that neurons failing the competition for a training vector are immediately available for the competitions for the subsequent training vectors. The architecture is implemented by the field programmable gate array (FPGA). It is used as a hardware accelerator in a system on programmable chip (SOPC) for realtime on-chip learning. Experimental results show that the SOPC has significantly lower training time than that of other k-WTA CL counterparts operating with or without hardware support.
Training in the Twenty-First Century: Where Do We Go from Here?
ERIC Educational Resources Information Center
Spikes, W. Franklin, III
Seven trends are emerging in the corporate training and development sector of human resource development (HRD). First, there is an increasing corporate commitment for training. Employers are viewing training today as an essential element in their competitive business strategies. Second, customer service training is becoming the competitive weapon…
Loosemore, Michael; Lightfoot, Joseph; Gatt, Ian; Hayton, Mike; Beardsley, Chris
2017-03-01
Background: The purpose of this investigation was to explore prospectively the nature and duration of hand and wrist injuries in training and competition in the Great Britain (GB) amateur boxing squad between 2005 and 2012. Methods: Longitudinal prospective injury surveillance of the GB boxing squad was performed from 2005 to 2012. The location, region affected, description, and the duration of each injury were recorded by the team doctor and team physiotherapist. We recorded whether the injury occurred during competition or training and also whether it was a new or a recurrent injury. The injury rate during competition was calculated as the number of injuries per 1000 hours. Results: Finger carpometacarpal instability and finger metacarpophalangeal joint extensor hood and capsule sprain also known as "boxer's knuckle" injuries were significantly more common than other injury diagnoses. The number of injuries during training or competition was similar, which is remarkable given the far greater number of training hours than competition hours performed. Injury rate for hand and wrist injuries in competition was 347 injuries per 1000 hours, while the estimated injury rate in training was <0.5 injuries per 1000 hours. Conclusion: Carpometacarpal instability and boxer's knuckle were more common than any other kind of hand and wrist injury in this cohort of elite amateur boxers. The rate of hand and wrist injuries was higher in competition than in training. Our study highlights the importance of hand and wrist injury prevention in the competition environment.
Sleep/wake behaviour of endurance cyclists before and during competition.
Lastella, Michele; Roach, Gregory Daniel; Halson, Shona Leigh; Martin, David Thomas; West, Nicholas Peter; Sargent, Charli
2015-01-01
Good sleep is critical for optimising recovery and athletic performance. Yet, few studies have investigated how athletes sleep before and during competition. The aim of this study was to determine whether such sleep is poorer than that before a usual training day. Twenty-one male endurance cyclists' (age: 19.9 ± 1.7 years) sleep/wake behaviour was assessed using wrist activity monitors for 11 nights, including a six-night baseline training phase, three nights before competition and two nights during competition. Cyclists had less sleep on the night before competition (6.5 ± 0.9 h) and during the first night of competition (6.8 ± 0.8 h) than at baseline (7.4 ± 0.6 h). Cyclists also went to bed and woke up earlier during competition than at baseline. Competition schedules and competition itself can disrupt the sleep/wake behaviour of athletes during competition. Future investigations should examine sleep during three stages of competition (i.e. before, during and after competition). This will help coaches develop a greater understanding of how sleep changes during different phases of competition and enable them to plan post-competition training programmes to ensure appropriate rest and recovery is obtained.
Alternative male morphs solve sperm performance/longevity trade-off in opposite directions.
Taborsky, Michael; Schütz, Dolores; Goffinet, Olivier; van Doorn, G Sander
2018-05-01
Males pursuing alternative reproductive tactics have been predicted to face a trade-off between maximizing either swimming performance or endurance of their sperm. However, empirical evidence for this trade-off is equivocal, which may be due to simplistic assumptions. In the shell-brooding cichlid fish Lamprologus callipterus , two Mendelian male morphs compete for fertilization by divergent means: Bourgeois nest males ejaculate sperm, on average, about six times farther from the unfertilized ova than do parasitic dwarf males. This asymmetry is opposite to the usual situation, in which bourgeois males typically benefit from superior fertilization opportunities, suggesting that nest males' sperm should persist longer than dwarf male sperm. The assumed trade-off between sperm swimming performance and longevity predicts that, in turn, sperm of dwarf males should outperform that of nest males in swimming efficiency. Measurement of sperm performance and endurance reveals that dwarf male spermatozoa swim straighter initially than those of nest males, but their motility declines earlier and their velocity slows down more abruptly. Nest male sperm survives longer, which relates to a larger sperm head plus midpiece, implying more mitochondria. Thus, the trade-off between sperm performance and endurance is optimized in opposite directions by alternative male morphs. We argue that the relative success of alternative sperm performance strategies can be influenced strongly by environmental factors such as the time window between gamete release and fertilization, and the position of gamete release. This is an important yet little understood aspect of gametic adaptations to sperm competition.
Instrumenting free-swimming dolphins echolocating in open water.
Martin, Stephen W; Phillips, Michael; Bauer, Eric J; Moore, Patrick W; Houser, Dorian S
2005-04-01
Dolphins within the Navy Marine Mammal Program use echolocation to effectively locate underwater mines. They currently outperform manmade systems at similar tasks, particularly in cluttered environments and on buried targets. In hopes of improving manmade mine-hunting sonar systems, two instrumentation packages were developed to monitor free-swimming dolphin motion and echolocation during open-water target detection tasks. The biosonar measurement tool (BMT) is carried by a dolphin and monitors underwater position and attitude while simultaneously recording echolocation clicks and returning echoes through high-gain binaural receivers. The instrumented mine simulator (IMS) is a modified bottom target that monitors echolocation signals arriving at the target during ensonification. Dolphin subjects were trained to carry the BMT in open-bay bottom-object target searches in which the IMS could serve as a bottom object. The instrumentation provides detailed data that reveal hereto-unavailable information on the search strategies of free-swimming dolphins conducting open-water, bottom-object search tasks with echolocation.
Instrumenting free-swimming dolphins echolocating in open water
NASA Astrophysics Data System (ADS)
Martin, Stephen W.; Phillips, Michael; Bauer, Eric J.; Moore, Patrick W.; Houser, Dorian S.
2005-04-01
Dolphins within the Navy Marine Mammal Program use echolocation to effectively locate underwater mines. They currently outperform manmade systems at similar tasks, particularly in cluttered environments and on buried targets. In hopes of improving manmade mine-hunting sonar systems, two instrumentation packages were developed to monitor free-swimming dolphin motion and echolocation during open-water target detection tasks. The biosonar measurement tool (BMT) is carried by a dolphin and monitors underwater position and attitude while simultaneously recording echolocation clicks and returning echoes through high-gain binaural receivers. The instrumented mine simulator (IMS) is a modified bottom target that monitors echolocation signals arriving at the target during ensonification. Dolphin subjects were trained to carry the BMT in open-bay bottom-object target searches in which the IMS could serve as a bottom object. The instrumentation provides detailed data that reveal hereto-unavailable information on the search strategies of free-swimming dolphins conducting open-water, bottom-object search tasks with echolocation. .
A wearable biofeedback control system based body area network for freestyle swimming.
Rui Li; Zibo Cai; WeeSit Lee; Lai, Daniel T H
2016-08-01
Wearable posture measurement units are capable of enabling real-time performance evaluation and providing feedback to end users. This paper presents a wearable feedback prototype designed for freestyle swimming with focus on trunk rotation measurement. The system consists of a nine-degree-of-freedom inertial sensor, which is built in a central data collection and processing unit, and two vibration motors for delivering real-time feedback. Theses devices form a fundamental body area network (BAN). In the experiment setup, four recreational swimmers were asked to do two sets of 4 x 25m freestyle swimming without and with feedback provided respectively. Results showed that real-time biofeedback mechanism improves swimmers kinematic performance by an average of 4.5% reduction in session time. Swimmers can gradually adapt to feedback signals, and the biofeedback control system can be employed in swimmers daily training for fitness maintenance.
Trites, Andrew W.; Rosen, David A. S.; Potvin, Jean
2016-01-01
Forces due to propulsion should approximate forces due to hydrodynamic drag for animals horizontally swimming at a constant speed with negligible buoyancy forces. Propulsive forces should also correlate with energy expenditures associated with locomotion—an important cost of foraging. As such, biologging tags containing accelerometers are being used to generate proxies for animal energy expenditures despite being unable to distinguish rotational movements from linear movements. However, recent miniaturizations of gyroscopes offer the possibility of resolving this shortcoming and obtaining better estimates of body accelerations of swimming animals. We derived accelerations using gyroscope data for swimming Steller sea lions (Eumetopias jubatus), and determined how well the measured accelerations correlated with actual swimming speeds and with theoretical drag. We also compared dive averaged dynamic body acceleration estimates that incorporate gyroscope data, with the widely used Overall Dynamic Body Acceleration (ODBA) metric, which does not use gyroscope data. Four Steller sea lions equipped with biologging tags were trained to swim alongside a boat cruising at steady speeds in the range of 4 to 10 kph. At each speed, and for each dive, we computed a measure called Gyro-Informed Dynamic Acceleration (GIDA) using a method incorporating gyroscope data with accelerometer data. We derived a new metric—Averaged Propulsive Body Acceleration (APBA), which is the average gain in speed per flipper stroke divided by mean stroke cycle duration. Our results show that the gyro-based measure (APBA) is a better predictor of speed than ODBA. We also found that APBA can estimate average thrust production during a single stroke-glide cycle, and can be used to estimate energy expended during swimming. The gyroscope-derived methods we describe should be generally applicable in swimming animals where propulsive accelerations can be clearly identified in the signal—and they should also prove useful for dead-reckoning and improving estimates of energy expenditures from locomotion. PMID:27285467
Alcaraz, Pedro E; Abraldes, J Arturo; Ferragut, Carmen; Rodríguez, Nuria; Argudo, Francisco M; Vila, Helena
2011-11-01
Water polo is a team sport characterized by a high-intensity, intermittent activity, where technical and tactical aspect are of a great importance. For that reason, the main aim of this study was to define the anthropometrical characteristics, maximum isometric grip strength, training and competition throwing velocities, and the efficacy indices in female high-level water polo players. A second purpose was to examine the differences between the throwing velocities in training vs. European championships in the water polo female national team. Ten elite trained female water polo players participated in this study. Before the competitive phase of their season, the following measures were taken: standard anthropometry, static and dynamic training throwing velocities, and hand-grip dynamometry. In the competitive phase, efficacy indices, average and maximum throwing velocities from all the participants were also determined. Significant differences (p ≤ 0.05) were found between different training situations and different competitive throwing velocities. We concluded that elite female water polo players modify their throwing velocity depending if the throw is performed during training or competitive situation.
Lathlean, Timothy J H; Gastin, Paul B; Newstead, Stuart; Finch, Caroline F
2018-07-01
Lathlean, TJH, Gastin, PB, Newstead, S, and Finch, CF. Elite junior Australian football players experience significantly different loads across levels of competition and training modes. J Strength Cond Res 32(7): 2031-2038, 2018-Well-developed physical qualities such as high jumping ability, running endurance, acceleration, and speed can help aspiring junior elite Australian football (AF) players transition to the Australian Football League competition. To do so, players need to experience sufficient load to enhance their physical resilience without increasing their risk of negative outcomes in terms of impaired wellness or injury. The aim of this study was to investigate the differences in load for different levels of competition and training modes across one competitive season. Elite junior AF players (n = 562, aged 17.7 ± 0.3, range: 16-18 years) were recruited from 9 teams across the under-18 state league competition in Victoria. All players recorded their training and match intensities according to the session rating of perceived exertion method. Training sessions were categorized according to skills, strength, conditioning, and other activities, whereas matches were identified according to level of competition. The loads in U18 state league matches (656.7 ± 210.9 au) were significantly higher (p = 0.027) than those in school matches (643.3 ± 260.9 au) and those in U18 representative matches (617.2 ± 175.4). Players, who undertook more than one match per week, experienced significantly less load in subsequent matches (p < 0.001). Furthermore, U18 state league training sessions carried the most load when compared with other training modes. This article highlights that different combinations of training and match involvement affect overall player load, which may predispose players to negative outcomes such as impaired wellness or increased injury risk.
Universal entrainment mechanism controls contact times with motile cells
NASA Astrophysics Data System (ADS)
Mathijssen, Arnold J. T. M.; Jeanneret, Raphaël; Polin, Marco
2018-03-01
Contact between particles and motile cells underpins a wide variety of biological processes, from nutrient capture and ligand binding to grazing, viral infection, and cell-cell communication. The window of opportunity for these interactions depends on the basic mechanism determining contact time, which is currently unknown. By combining experiments on three different species—Chlamydomonas reinhardtii, Tetraselmis subcordiforms, and Oxyrrhis marina—with simulations and analytical modeling, we show that the fundamental physical process regulating proximity to a swimming microorganism is hydrodynamic particle entrainment. The resulting distribution of contact times is derived within the framework of Taylor dispersion as a competition between advection by the cell surface and microparticle diffusion, and predicts the existence of an optimal tracer size that is also observed experimentally. Spatial organization of flagella, swimming speed, and swimmer and tracer size influence entrainment features and provide tradeoffs that may be tuned to optimize the estimated probabilities for microbial interactions like predation and infection.
Water safety in the bush: strategies for addressing training needs in remote areas.
Beattie, N; Shaw, P; Larson, A
2008-01-01
This article describes a unique, remote, water safety-training program delivered to 11 remote Australian communities during 2006-2007. The program, known as 'Water Safety in the Bush', was developed by Combined Universities Centre for Rural Health in Geraldton Western Australia in consultation with the Commonwealth Government Department of Health and Ageing, and the Royal Life Saving Society of Australia. Drowning and near drowning are major causes of childhood death and injury in rural and remote Australia, making improved water safety awareness and skills a public health priority. Water Safety in the Bush employed a flexible, community development model to meet the special requirements of remote and isolated communities. The model had three elements: coordination by a local organisation; a water safety instruction program based on a Royal Life Saving Society of Australia curriculum adapted to meet local priorities; and strategies for sustainability. In the delivery of the program a total of 873 children and 219 adults received swimming and water safety instruction; 47 adults and older children received first-aid training; and 38 community members became AUSTAWIM (the Australian Council for the Teaching of Swimming and Water Safety) accredited instructors. Project evaluation showed parents and community organisations were very satisfied with the program which met a real need. Parents and instructors gave evidence of children's increased skills in water safety, swimming ability, life-saving and water confidence. Training programs with greater contact hours showed greater skill gains. Sustainability strategies included accreditation of local AUSTSWIM instructors, the erection of water safety signs, sourcing of continuing funding, and the introduction of water safety theory into the school curriculum. Flexibility was the major success factor. Within the parameters of minimum guidelines, communities were encouraged to choose the timing, venue and delivery mode of the training to ensure the program was best suited to the local community. Community ownership was achieved by requiring that local organisations design and implement the projects. Designing programs that addressed local constraints ensured high participation rates. A number of challenges were also identified. Not all community organisations had the capacity to take on the coordinating role, and struggled to effectively deliver a sustainable program. Other models may be needed for these communities. Accessing appropriately qualified water safety instructors in local areas also proved difficult at several of the sites. Further, designing standardised outcome evaluation strategies that could be implemented across all participating sites was problematic. Remote and isolated communities have a pressing need to gain the knowledge and skills necessary for water safety and survival. Standard training programs, which in the case of swimming and water safety instruction are generally run in two-week blocks, are often not feasible. Models for delivering training, which give resources and power to local organisations to find innovative ways to meet their priorities, build capacity and ensure high participation rates.
Redox, iron, and nutritional status of children during swimming training.
Kabasakalis, Athanasios; Kalitsis, Konstantinos; Nikolaidis, Michalis G; Tsalis, George; Kouretas, Dimitris; Loupos, Dimitris; Mougios, Vassilis
2009-11-01
Effects of exercise training on important determinants of children's long-term health, such as redox and iron status, have not been adequately investigated. The aim of the present study was to examine changes in markers of the redox, iron and nutritional status of boy and girl swimmers during a prolonged period of training. 11 boys and 13 girls, aged 10-11 years, were members of a swimming club. They were assessed at the beginning of the training season, at 13 weeks and at 23 weeks through blood sampling and recording of the diet. Reduced glutathione increased at 13 and 23 weeks, whereas oxidised glutathione decreased at 13 weeks, resulting in an increase of the reduced/oxidised glutathione ratio at 13 and 23 weeks. Total antioxidant capacity, catalase, thiobarbituric acid-reactive substances, hemoglobin, transferrin saturation and ferritin did not change significantly. Carbohydrate intake was below 50% of energy and fat intake was above 40% of energy. Intakes of saturated fatty acids and cholesterol were excessive. Iron intake was adequate but intakes of folate, vitamin E, calcium and magnesium did not meet the recommended daily allowances. No significant differences were found between sexes in any of the parameters measured. In conclusion, child swimmers improved the redox status of glutathione during training, although the intake of antioxidant nutrients did not change. The iron status was not impaired by training. Suboptimal intake of several nutrients suggests the need for nutritional monitoring and education of children athletes.
Slimani, Maamer; Davis, Philip; Franchini, Emerson; Moalla, Wassim
2017-10-01
The aim of this short review was to summarize data pertaining to the rating of perceived exertion (RPE) methods (RPE value and session-RPE) during combat sport-specific activities (i.e., competition and training) based on many factors, including contest type (i.e., official vs. simulated vs. training), combat rounds, age of participants and muscle groups, and their correlation with physiological variables (i.e., blood lactate concentration [La] and heart rate [HR]). The current review shows higher RPE in a match of mixed martial arts (MMAs) than Brazilian jiu-jitsu and kickboxing matches and during the competitive period compared with the precompetitive period. This could be explained by the longer duration of bouts, the higher percentage contribution of aerobic metabolism in MMA than other combat sports and contest type differences (simulated vs. official matches). Thus, this review found significant correlations between RPE or session-RPE, [La] and HR. Particularly, there was a stronger correlation between RPE and [La] during official striking (r = 0.81) than grappling combat sports matches (r = 0.53). In addition, a variation of correlation (moderate to large) between session-RPE and HR-based methods has been reported (i.e., Edwards' training load [r ranged between 0.58 and 0.95] and Banister training impulse [r ranged between 0.52 and 0.86]). Specifically, stronger correlation was apparent in combat sport competition that required a much higher percentage contribution of aerobic metabolism (e.g., karate) and in adult athletes than anaerobic-based combat sports (e.g., taekwondo) and young athletes, respectively. Indeed, the current review highlights that the correlations between session-RPE and HR-based methods were higher during official competition than training sessions. Session-RPE was affected by participants' competitive level, the intensity of session (high vs. low), the training modalities (tactical-technical vs. technical-development vs. simulated competition), and the training volume in combat sports athletes. Rating of perceived exertion is a valid tool for quantifying internal training and combat loads during short- and long-term training and simulated and official competitions in novice and elite combat sport athletes. Furthermore, both RPE methods may be a more reliable measure of intensity or effort when both anaerobic and aerobic systems are appreciably activated. Coaches, sports scientists, and athletes can use session-RPE method to quantify short-term training and combat loads in adult athletes during precompetitive period much more than long-term training and in young athletes during the competitive period. They can also use RPE to monitor combat and short- and long-term training loads to better plan and assist training programs and competitions.
Hosang, Leon; Yusifov, Rashad; Löwel, Siegrid
2018-01-01
For routine behavioral tasks, mice predominantly rely on olfactory cues and tactile information. In contrast, their visual capabilities appear rather restricted, raising the question whether they can improve if vision gets more behaviorally relevant. We therefore performed long-term training using the visual water task (VWT): adult standard cage (SC)-raised mice were trained to swim toward a rewarded grating stimulus so that using visual information avoided excessive swimming toward nonrewarded stimuli. Indeed, and in contrast to old mice raised in a generally enriched environment (Greifzu et al., 2016), long-term VWT training increased visual acuity (VA) on average by more than 30% to 0.82 cycles per degree (cyc/deg). In an individual animal, VA even increased to 1.49 cyc/deg, i.e., beyond the rat range of VAs. Since visual experience enhances the spatial frequency threshold of the optomotor (OPT) reflex of the open eye after monocular deprivation (MD), we also quantified monocular vision after VWT training. Monocular VA did not increase reliably, and eye reopening did not initiate a decline to pre-MD values as observed by optomotry; VA values rather increased by continued VWT training. Thus, optomotry and VWT measure different parameters of mouse spatial vision. Finally, we tested whether long-term MD induced ocular dominance (OD) plasticity in the visual cortex of adult [postnatal day (P)162-P182] SC-raised mice. This was indeed the case: 40-50 days of MD induced OD shifts toward the open eye in both VWT-trained and, surprisingly, also in age-matched mice without VWT training. These data indicate that (1) long-term VWT training increases adult mouse VA, and (2) long-term MD induces OD shifts also in adult SC-raised mice.
Oxygen Uptake Kinetics Is Slower in Swimming Than Arm Cranking and Cycling during Heavy Intensity
Sousa, Ana; Borrani, Fabio; Rodríguez, Ferran A.; Millet, Grégoire P.
2017-01-01
Oxygen uptake (V·O2) kinetics has been reported to be influenced by the activity mode. However, only few studies have compared V·O2 kinetics between activities in the same subjects in which they were equally trained. Therefore, this study compared the V·O2 kinetics response to swimming, arm cranking, and cycling within the same group of subjects within the heavy exercise intensity domain. Ten trained male triathletes (age 23.2 ± 4.5 years; height 180.8 ± 8.3 cm; weight 72.3 ± 6.6 kg) completed an incremental test to exhaustion and a 6-min heavy constant-load test in the three exercise modes in random order. Gas exchange was measured by a breath-by-breath analyzer and the on-transient V·O2 kinetics was modeled using bi-exponential functions. V·O2peak was higher in cycling (65.6 ± 4.0 ml·kg−1·min−1) than in arm cranking or swimming (48.7 ± 8.0 and 53.0 ± 6.7 ml·kg−1·min−1; P < 0.01), but the V·O2 kinetics were slower in swimming (τ1 = 31.7 ± 6.2 s) than in arm cranking (19.3 ± 4.2 s; P = 0.001) and cycling (12.4 ± 3.7 s; P = 0.001). The amplitude of the primary component was lower in both arm cranking and swimming (21.9 ± 4.7 and 28.4 ± 5.1 ml·kg−1·min−1) compared with cycling (39.4 ± 4.1 ml·kg−1·min−1; P = 0.001). Although the gain of the primary component was higher in arm cranking compared with cycling (15.3 ± 4.2 and 10.7 ± 1.3 ml·min−1·W−1; P = 0.02), the slow component amplitude, in both absolute and relative terms, did not differ between exercise modes. The slower V·O2 kinetics during heavy-intensity swimming is exercise-mode dependent. Besides differences in muscle mass and greater type II muscle fibers recruitment, the horizontal position adopted and the involvement of trunk and lower-body stabilizing muscles could be additional mechanisms that explain the differences between exercise modalities. PMID:28919863
Swimming Training Reduces Neuroma Pain by Regulating Neurotrophins
TIAN, JINGE; YU, TINGTING; XU, YONGMING; PU, SHAOFENG; LV, YINGYING; ZHANG, XIN; DU, DONGPING
2018-01-01
ABSTRACT Introduction Neuroma formation after peripheral nerve transection leads to severe neuropathic pain in amputees. Previous studies suggested that physical exercise could bring beneficial effect on alleviating neuropathic pain. However, the effect of exercise on neuroma pain still remained unclear. In addition, long-term exercise can affect the expression of neurotrophins (NT), such as nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF), which play key roles in nociceptor sensitization and nerve sprouting after nerve injury. Here, we investigated whether long-term swimming exercise could relieve neuroma pain by modulating NT expression. Methods We used a tibial neuroma transposition (TNT) rat model to mimic neuroma pain. After TNT surgery, rats performed swimming exercise for 5 wk. Neuroma pain and tactile sensitivities were detected using von Frey filaments. Immunofluorescence was applied to analyze neuroma formation. NGF and BDNF expressions in peripheral neuroma, dorsal root ganglion, and the spinal cord were measured using enzyme-linked immunosorbent assay and Western blotting. Results TNT led to neuroma formation, induced neuroma pain, and mechanical allodynia in hind paw. Five-week swimming exercise inhibited neuroma formation and relieved mechanical allodynia in the hind paw and neuroma pain in the lateral ankle. The analgesic effect lasted for at least 1 wk, even when the exercise ceased. TNT elevated the expressions of BDNF and NGF in peripheral neuroma, dorsal root ganglion, and the spinal cord to different extents. Swimming also decreased the elevation of NT expression. Conclusions Swimming exercise not only inhibits neuroma formation induced by nerve transection but also relieves pain behavior. These effects might be associated with the modulation of NT. PMID:28846565
Swimming Training Reduces Neuroma Pain by Regulating Neurotrophins.
Tian, Jinge; Yu, Tingting; Xu, Yongming; Pu, Shaofeng; Lv, Yingying; Zhang, Xin; DU, Dongping
2018-01-01
Neuroma formation after peripheral nerve transection leads to severe neuropathic pain in amputees. Previous studies suggested that physical exercise could bring beneficial effect on alleviating neuropathic pain. However, the effect of exercise on neuroma pain still remained unclear. In addition, long-term exercise can affect the expression of neurotrophins (NT), such as nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF), which play key roles in nociceptor sensitization and nerve sprouting after nerve injury. Here, we investigated whether long-term swimming exercise could relieve neuroma pain by modulating NT expression. We used a tibial neuroma transposition (TNT) rat model to mimic neuroma pain. After TNT surgery, rats performed swimming exercise for 5 wk. Neuroma pain and tactile sensitivities were detected using von Frey filaments. Immunofluorescence was applied to analyze neuroma formation. NGF and BDNF expressions in peripheral neuroma, dorsal root ganglion, and the spinal cord were measured using enzyme-linked immunosorbent assay and Western blotting. TNT led to neuroma formation, induced neuroma pain, and mechanical allodynia in hind paw. Five-week swimming exercise inhibited neuroma formation and relieved mechanical allodynia in the hind paw and neuroma pain in the lateral ankle. The analgesic effect lasted for at least 1 wk, even when the exercise ceased. TNT elevated the expressions of BDNF and NGF in peripheral neuroma, dorsal root ganglion, and the spinal cord to different extents. Swimming also decreased the elevation of NT expression. Swimming exercise not only inhibits neuroma formation induced by nerve transection but also relieves pain behavior. These effects might be associated with the modulation of NT.
Cechella, José L; Leite, Marlon R; Gai, Rafaela M; Zeni, Gilson
2014-08-01
Selenium is an essential trace element for human health and has received attention for its role as a nutrient. The combination of exercise and nutrients has been proposed to promote health. The aim of this study was to determine the effects of a diet supplemented with diphenyl diselenide (PhSe)2 and swimming exercise on memory of middle-aged rats. Male Wistar rats (12months) received standard diet chow supplemented with 1ppm of (PhSe)2 for 4weeks. Rats were submitted to swimming training (20min per day for 4weeks). After 4weeks, memory was evaluated in the object recognition test (ORT) and in the object location test (OLT). The hippocampal levels of phosphorylated cAMP-response element-binding protein (CREB) were determined. The results of the present study demonstrated that the association of (PhSe)2-supplemented diet and swimming exercise improved short-term memory, long-term memory and spatial learning, and this effect was not related to the increase in hippocampal p-CREB levels in middle-age rats. This study also revealed that middle-aged rats in the swimming exercise group had the best performance in short- and long-term memory. In conclusion, we demonstrated that swimming exercise, (PhSe)2-supplemented diet or the association of these factors improved learning and memory functioning. The hippocampal levels of CREB were not directly related to the benefits of swimming exercise and (PhSe)2-supplemented diet association in memory of middle-aged rats. Copyright © 2014 Elsevier Inc. All rights reserved.
Tabassum, Heena; Frey, Julietta U
2013-12-01
Hippocampal long-term potentiation (LTP) is a cellular model of learning and memory. An early form of LTP (E-LTP) can be reinforced into its late form (L-LTP) by various behavioral interactions within a specific time window ("behavioral LTP-reinforcement"). Depending on the type and procedure used, various studies have shown that stress differentially affects synaptic plasticity. Under low stress, such as novelty detection or mild foot shocks, E-LTP can be transformed into L-LTP in the rat dentate gyrus (DG). A reinforcing effect of a 2-min swim, however, has only been shown in (Korz and Frey (2003) J Neurosci 23:7281-7287; Korz and Frey (2005) J Neurosci 25:7393-7400; Ahmed et al. (2006) J Neurosci 26:3951-3958; Sajikumar et al., (2007) J Physiol 584.2:389-400) so far. We have reinvestigated these studies using the same as well as an improved recording technique which allowed the recording of field excitatory postsynaptic potentials (fEPSP) and the population spike amplitude (PSA) at their places of generation in freely moving rats. We show that acute swim stress led to a long-term depression (LTD) in baseline values of PSA and partially fEPSP. In contrast to earlier studies a LTP-reinforcement by swimming could never be reproduced. Our results indicate that 2-min swim stress influenced synaptic potentials as well as E-LTP negatively. Copyright © 2013 Wiley Periodicals, Inc.
Glia protein aquaporin-4 regulates aversive motivation of spatial memory in Morris water maze.
Zhang, Ji; Li, Ying; Chen, Zhong-Guo; Dang, Hui; Ding, Jian-Hua; Fan, Yi; Hu, Gang
2013-12-01
Although extensive investigation has revealed that an astrocyte-specific protein aquaporin-4 (AQP4) participates in regulating synaptic plasticity and memory, a functional relationship between AQP4 and learning processing has not been clearly established. This study was designed to test our hypothesis that AQP4 modulates the aversive motivation in Morris water maze (MWM). Using hidden platform training, we observed that AQP4 KO mice significantly decreased their swimming velocity compared with wild-type (WT) mice. To test for a relationship between velocities and escape motivation, we removed the platform and subjected a new group of mice similar to the session of hidden platform training. We found that KO mice exhibited a gradual reduction in swimming velocity, while WT mice did not alter their velocity. In the subsequent probe trial, KO mice after no platform training significantly decreased their mean velocity compared with those KO mice after hide platform training. However, all of KO mice were not impaired in their ability to locate a visible, cued escape platform. Our findings, along with a previous report that AQP4 regulates memory consolidation, implicate a novel role for this glial protein in modulating the aversive motivation in spatial learning paradigm. © 2013 John Wiley & Sons Ltd.
Variation in the production rate of biosonar signals in freshwater porpoises.
Kimura, Satoko; Akamatsu, Tomonari; Wang, Ding; Li, Songhai; Wang, Kexiong; Yoda, Ken
2013-05-01
The biosonar (click train) production rate of ten Yangtze finless porpoises and their behavior were examined using animal-borne data loggers. The sound production rate varied from 0 to 290 click trains per 10-min time interval. Large individual differences were observed, regardless of body size. Taken together, however, sound production did not differ significantly between daytime and nighttime. Over the 172.5 h of analyzed recordings, an average of 99.0% of the click trains were produced within intervals of less than 60 s, indicating that during a 1-min interval, the number of click trains produced by each porpoise was typically greater than one. Most of the porpoises exhibited differences in average swimming speed and depth between day and night. Swimming speed reductions and usage of short-range sonar, which relates to prey-capture attempts, were observed more often during nighttime. However, biosonar appears to be affected not only by porpoise foraging, but also by their sensory environment, i.e., the turbid Yangtze River system. These features will be useful for passive acoustic detection of the porpoises. Calculations of porpoise density or abundance should be conducted carefully because large individual differences in the sound production rate will lead to large estimation error.
Worker Training: Competing in the New International Economy.
ERIC Educational Resources Information Center
Congress of the U.S., Washington, DC. Office of Technology Assessment.
Workers' skills are critical to U.S. industrial productivity and competitiveness and to maintaining living standards. Training is the key. Good training pays--for workers whose skills are upgraded, for companies seeking a competitive edge, and for the nation in overall productivity. However, workers in other countries are better trained than most…
Terada, S; Yokozeki, T; Kawanaka, K; Ogawa, K; Higuchi, M; Ezaki, O; Tabata, I
2001-06-01
This study was performed to assess the effects of short-term, extremely high-intensity intermittent exercise training on the GLUT-4 content of rat skeletal muscle. Three- to four-week-old male Sprague-Dawley rats with an initial body weight ranging from 45 to 55 g were used for this study. These rats were randomly assigned to an 8-day period of high-intensity intermittent exercise training (HIT), relatively high-intensity intermittent prolonged exercise training (RHT), or low-intensity prolonged exercise training (LIT). Age-matched sedentary rats were used as a control. In the HIT group, the rats repeated fourteen 20-s swimming bouts with a weight equivalent to 14, 15, and 16% of body weight for the first 2, the next 4, and the last 2 days, respectively. Between exercise bouts, a 10-s pause was allowed. RHT consisted of five 17-min swimming bouts with a 3-min rest between bouts. During the first bout, the rat swam without weight, whereas during the following four bouts, the rat was attached to a weight equivalent to 4 and 5% of its body weight for the first 5 days and the following 3 days, respectively. Rats in the LIT group swam 6 h/day for 8 days in two 3-h bouts separated by 45 min of rest. In the first experiment, the HIT, LIT, and control rats were compared. GLUT-4 content in the epitrochlearis muscle in the HIT and LIT groups after training was significantly higher than that in the control rats by 83 and 91%, respectively. Furthermore, glucose transport activity, stimulated maximally by both insulin (2 mU/ml) (HIT: 48%, LIT: 75%) and contractions (25 10-s tetani) (HIT: 55%, LIT: 69%), was higher in the training groups than in the control rats. However, no significant differences in GLUT-4 content or in maximal glucose transport activity in response to both insulin and contractions were observed between the two training groups. The second experiment demonstrated that GLUT-4 content after HIT did not differ from that after RHT (66% higher in trained rats than in control). In conclusion, the present investigation demonstrated that 8 days of HIT lasting only 280 s elevated both GLUT-4 content and maximal glucose transport activity in rat skeletal muscle to a level similar to that attained after LIT, which has been considered a tool to increase GLUT-4 content maximally.
Express-evaluation of the psycho-physiological condition of Paralympic athletes
Drozdovski, Alexander; Gromova, Irina; Korotkov, Konstantin; Shelkov, Oleg; Akinnagbe, Femi
2012-01-01
Objective Evaluation of elite athletes’ psycho-physiological condition at various stages of preparation and in international competition. Design Athletes were tested during training and participation in international competition using methods of galvanic skin response (GSR) and gas discharge visualization (GDV). Setting Saint Petersburg Federal Research Institute of Physical Culture and Sport, Russia and Paralympic athletic training camp, Norway. Participants Eighteen athletes from Russia’s Skiing and Biathlon Paralympic Team. All athletes had some level of damage to their musculoskeletal system. Main outcome measures Stress level (SL), energy potential (EP), and psycho-emotional tension (PET). Results It was found that the higher the level of EP achieved by the athlete in the training period, the lower the SL in the competition time. The SL of an athlete recorded in the training period significantly correlates with the SL both before and at the time of competition. The PET and SL before the World Cup was negatively correlated to the results of skiing competitions. Conclusion Evaluation of PET, EP, and SL through GSR and GDV offers a fast, highly precise, non-invasive method to assess an athlete’s level of readiness during both training and at the time of competition. PMID:24198605
Glucose transporters and maximal transport are increased in endurance-trained rat soleus
NASA Technical Reports Server (NTRS)
Slentz, C. A.; Gulve, E. A.; Rodnick, K. J.; Henriksen, E. J.; Youn, J. H.; Holloszy, J. O.
1992-01-01
Voluntary wheel running induces an increase in the concentration of the regulatable glucose transporter (GLUT4) in rat plantaris muscle but not in soleus muscle (K. J. Rodnick, J. O. Holloszy, C. E. Mondon, and D. E. James. Diabetes 39: 1425-1429, 1990). Wheel running also causes hypertrophy of the soleus in rats. This study was undertaken to ascertain whether endurance training that induces enzymatic adaptations but no hypertrophy results in an increase in the concentration of GLUT4 protein in rat soleus (slow-twitch red) muscle and, if it does, to determine whether there is a concomitant increase in maximal glucose transport activity. Female rats were trained by treadmill running at 25 m/min up a 15% grade, 90 min/day, 6 days/wk for 3 wk. This training program induced increases of 52% in citrate synthase activity, 66% in hexokinase activity, and 47% in immunoreactive GLUT4 protein concentration in soleus muscles without causing hypertrophy. Glucose transport activity stimulated maximally with insulin plus contractile activity was increased to roughly the same extent (44%) as GLUT4 protein content in soleus muscle by the treadmill exercise training. In a second set of experiments, we examined whether a swim-training program increases glucose transport activity in the soleus in the presence of a maximally effective concentration of insulin. The swimming program induced a 44% increase in immunoreactive GLUT4 protein concentration. Glucose transport activity maximally stimulated with insulin was 62% greater in soleus muscle of the swimmers than in untrained controls. Training did not alter the basal rate of 2-deoxyglucose uptake.(ABSTRACT TRUNCATED AT 250 WORDS).
Fluid and Electrolyte Needs for Training, Competition, and Recovery
2011-01-01
begin both training and competition in a state of fluid deficit. Analysis of samples collected from elite football ( soccer ) players before training...surprisingly, samples collected from players before a competitive game revealed that 8 of the 20 outfield players had a urine osmolality in excess of...2007) reported that basketball players attempted fewer shots and were less able to make shots linked with movement (e.g. lay-up) when dehydration had
Loosemore, Michael; Lightfoot, Joseph; Palmer-Green, Deborah; Gatt, Ian; Bilzon, James; Beardsley, Chris
2015-09-01
There has been no comprehensive injury report of elite-level amateur boxers in competition and training. We reviewed injuries in training and competition in the Great Britain (GB) amateur boxing squad between 2005 and 2009. Longitudinal, prospective injury surveillance over 5 years of the GB boxing squad from 2005 to 2009. 66 boxers passed through the squad. The location, region affected, description, and the duration of each injury were recorded by the team doctor and team physiotherapist. We recorded whether the injury occurred during competition or training, and also whether it was a new or a recurrent injury. The injury rate during competition was calculated as the number of injuries per 1000 h. More injuries affected the hand than any other body location. This was the case overall, in training and competition individually, and for both new and recurrent injuries. More injuries occurred during training than during competition, and most injuries were new rather than recurrent. Total injury rate during competition was 828 per 1000 h and hand injury rate in competition was 302 injuries per 1000 h. Hand injury rate in competition was significantly higher than at the other locations. The incidence of concussion is comparatively low. Injury prevention should aim to protect the hands and wrists of elite amateur boxers. 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.
ERIC Educational Resources Information Center
Goldfarb, Joseph M.
1995-01-01
The article presents a method for swimming teachers and coaches to stave off workout boredom in their students by using a circuit in the pool. After explaining how to set up a training circuit, the article describes sample stations and notes important safety precautions. (SM)
Yu, Kyung-Hun; Suk, Min-Hwa; Kang, Shin-Woo; Shin, Yun-A
2014-10-01
The purpose of this study was to investigate the effect of combined linear and nonlinear periodic training on physical fitness and competition times in finswimmers. The linear resistance training model (6 days/week) and nonlinear underwater training (4 days/week) were applied to 12 finswimmers (age, 16.08± 1.44 yr; career, 3.78± 1.90 yr) for 12 weeks. Body composition measures included weight, body mass index (BMI), percent fat, and fat-free mass. Physical fitness measures included trunk flexion forward, trunk extension backward, sargent jump, 1-repetition-maximum (1 RM) squat, 1 RM dead lift, knee extension, knee flexion, trunk extension, trunk flexion, and competition times. Body composition and physical fitness were improved after the 12-week periodic training program. Weight, BMI, and percent fat were significantly decreased, and trunk flexion forward, trunk extension backward, sargent jump, 1 RM squat, 1 RM dead lift, and knee extension (right) were significantly increased. The 50- and 100-m times significantly decreased in all 12 athletes. After 12 weeks of training, all finswimmers who participated in this study improved their times in a public competition. These data indicate that combined linear and nonlinear periodic training enhanced the physical fitness and competition times in finswimmers.
A Comparison of Speed Profiles During Training and Competition in Elite Wheelchair Rugby Players.
Rhodes, James M; Mason, Barry S; Paulson, Thomas A W; Goosey-Tolfrey, Victoria L
2017-07-01
To investigate the speed profiles of individual training modes in comparison with wheelchair rugby (WCR) competition across player classifications. Speed profiles of 15 international WCR players were determined using a radio-frequency-based indoor tracking system. Mean and peak speed (m/s), work:rest ratios, and the relative time spent in (%) and number of high-speed activities performed were measured across training sessions (n = 464) and international competition (n = 34). Training was classified into 1 of 4 modes: conditioning (n = 71), skill-based (n = 133), game-related (n = 151), and game-simulation drills (n = 109). Game-simulation drills were further categorized by the structured duration, which were 3-min game clock (n = 44), 8-min game clock (n = 39), and 10-min running clock (n = 26). Players were grouped by their International Wheelchair Rugby Federation classification as either low-point (≤1.5; n = 8) or high-point players (≥2.0; n = 7). Conditioning drills were shown to exceed the demands of competition, irrespective of classification (P ≤ .005; effect size [ES] = 0.6-2.0). Skill-based and game-related drills underrepresented the speed profiles of competition (P ≤ .005; ES = 0.5-1.1). Mean speed and work:rest ratios were significantly lower during 3- and 8-min game-simulation drills in relation to competition (P ≤ .039; ES = 0.5-0.7). However, no significant differences were identified between the 10-min running clock and competition. Although game-simulation drills provided the closest representation of competition, the structured duration appeared important since the 10-min running clock increased training specificity. Coaches can therefore modify the desired training response by making subtle changes to the format of game-simulation drills.
Totou, N L; Moura, S S; Coelho, D B; Oliveira, E C; Becker, L K; Lima, W G
2018-03-01
Experimental studies in animal models have described the benefits of physical exercise (PE) to kidney diseases associated with hypertension. Land- and water-based exercises induce different responses in renal function. Our aim was to evaluate the renal alterations induced by different environments of PE in spontaneously hypertensive rats (SHRs). The SHRs were divided into sedentary (S), swimming exercise (SE), and running exercise (RE) groups, and were trained for 8 weeks under similar intensities (60 min/day). Arterial pressure (AP) and heart rate (HR) were recorded. The renal function was evaluated through urinary volume at each week of training; sodium and potassium excretions, plasma and urinary osmolarities, glomerular filtration rate (GFR), levels of proteinuria, and renal damage were determined. SE and RE rats presented reduced mean AP, systolic blood pressure, and HR in comparison with S group. SE and RE rats showed higher urine osmolarity compared with S. SE rats showed higher free water clearance (P < 0.01), lower urinary density (P < 0.0001), and increased weekly urine volume (P < 0.05) in comparison with RE and S groups. GFR was increased in both SE and RE rats. The proteinuria of SE (7.0 ± 0.8 mg/24 h) rats was decreased at the 8th week of the PE in comparison with RE (9.6 ± 0.8 mg/24 h) and S (9.8 ± 0.5 mg/24 h) groups. The glomerulosclerosis was reduced in SE rats (P < 0.02). SE produced different response in renal function in comparison with RE, in which only swimming-trained rats had better profile for proteinuria and glomerulosclerosis.
Pre-competition habits and injuries in Taekwondo athletes
Kazemi, Mohsen; Shearer, Heather; Su Choung, Young
2005-01-01
Background Over the past decade, there has been heightened interest in injury rates sustained by martial arts athletes, and more specifically, Taekwondo athletes. Despite this interest, there is a paucity of research on pre-competition habits and training of these athletes. The purpose of this pilot study was to assess training characteristics, competition preparation habits, and injury profiles of Taekwondo athletes. Methods A retrospective survey of Canadian male and female Taekwondo athletes competing in a national tournament was conducted. Competitors at a Canadian national level tournament were given a comprehensive survey prior to competition. Items on training characteristics, diet, and injuries sustained during training and competition were included. Questionnaires were distributed to 60 athletes. Results A response rate of 46.7% was achieved. Of those that responded, 54% dieted prior to competition, and 36% dieted and exercised pre-competition. Sixty-four percent of the athletes practised between 4–6 times per week, with 54% practicing 2 hours per session. Lower limb injuries were the most common (46.5%), followed by upper extremity (18%), back (10%), and head (3.6%). The majority of injuries consisted of sprains/strains (45%), followed by contusions, fractures, and concussions. More injuries occurred during training, including 59% of first injuries. Conclusion More research needs to be conducted to further illustrate the need for appropriate regulations on weight cycling and injury prevention. PMID:15921510
Garciarena, Carolina D; Pinilla, Oscar A; Nolly, Mariela B; Laguens, Ruben P; Escudero, Eduardo M; Cingolani, Horacio E; Ennis, Irene L
2009-04-01
The effect of endurance training (swimming 90 min/d for 5 days a week for 60 days) on cardiac hypertrophy was investigated in the spontaneously hypertensive rat (SHR). Sedentary SHRs (SHR-Cs) and normotensive Wistar rats were used as controls. Exercise training enhanced myocardial hypertrophy assessed by left ventricular weight/tibial length (228+/-7 versus 251+/-5 mg/cm in SHR-Cs and exercised SHRs [SHR-Es], respectively). Myocyte cross-sectional area increased approximately 40%, collagen volume fraction decreased approximately 50%, and capillary density increased approximately 45% in SHR-Es compared with SHR-Cs. The mRNA abundance of atrial natriuretic factor and myosin light chain 2 was decreased by the swimming routine (100+/-19% versus 41+/-10% and 100+/-8% versus 61+/-9% for atrial natriuretic factor and myosin light chain 2 in SHR-Cs and SHR-Es, respectively). The expression of sarcoplasmic reticulum Ca(2+) pump was significantly augmented, whereas that of Na(+)/Ca(2+) exchanger was unchanged (93+/-7% versus 167+/-8% and 158+/-13% versus 157+/-7%, sarcoplasmic reticulum Ca(2+) pump and Na(+)/Ca(2+) exchanger in SHR-Cs and SHR-Es, respectively; P<0.05). Endurance training inhibited apoptosis, as reflected by a decrease in caspase 3 activation and poly(ADP-ribose) polymerase-1 cleavage, and normalized calcineurin activity without inducing significant changes in the phosphatidylinositol 3-kinase/Akt pathway. The swimming routine improved midventricular shortening determined by echocardiography (32.4+/-0.9% versus 36.9+/-1.1% in SHR-Cs and SHR-Es, respectively; P<0.05) and decreased the left ventricular free wall thickness/left ventricular cavity radius toward an eccentric model of cardiac hypertrophy (0.59+/-0.02 versus 0.53+/-0.01 in SHR-Cs and SHR-Es, respectively; P<0.05). In conclusion, we present data demonstrating the effectiveness of endurance training to convert pathological into physiological hypertrophy improving cardiac performance. The reduction of myocardial fibrosis and calcineurin activity plus the increase in capillary density represent factors to be considered in determining this beneficial effect.
Lyakh, Vladimir; Bujas, Przemysław; Witkowski, Zbigniew; Zając, Tomasz; Litkowycz, Ryszard; Banyś, Damian
2016-01-01
Abstract The main goal of this study was to present a review of current knowledge and modern trends in periodization of the training process in team sports. The research objectives were: an analysis of various aspects of periodization of the annual training cycle for elite athletes practicing team sport games, an attempt to determine both the examined and unexamined issues related with periodization of training as well as to indicate directions for further research, and finally, presentation of different training loads and competitions in micro-, meso- and macrocycles. The research consisted of the analysis and generalization of the bibliography, methods of monitoring training and competition loads of the Polish national U17 female soccer team in the seasons 2011/2012 and 2012/2013, as well as of the female basketball division one club in the season 2014/2015. Findings of the present study indicate resolved as well as unresolved aspects of annual training cycle periodization in team sport games and provide information on the types of training and competitive workload planning in micro-, meso- and macrocycles.
Bonnar, Daniel; Bartel, Kate; Kakoschke, Naomi; Lang, Christin
2018-03-01
Athletes experience various situations and conditions that can interfere with their sleep, which is crucial for optimal psychological and physiological recovery as well as subsequent performance. Conventional sleep screening and intervention approaches may not be efficacious for athletes given their lifestyle, the demands of training and travel associated with interstate/international competition. The present systematic review aimed to summarize and evaluate sleep intervention studies targeting subsequent performance and recovery in competitive athletes. Based on the findings, a secondary aim was to outline a possible sleep intervention for athletes, including recommendations for content, mode of delivery and evaluation. A systematic review was conducted based on the PRISMA guidelines in May 2016 with an update completed in September 2017. Ten studies met our inclusion criteria comprising a total of 218 participants in the age range of 18-24 years with athletes from various sports (e.g., swimming, soccer, basketball, tennis). A modified version of the quality assessment scale developed by Abernethy and Bleakley was used to evaluate the quality of the studies. The included studies implemented several sleep interventions, including sleep extension and napping, sleep hygiene, and post-exercise recovery strategies. Evidence suggests that sleep extension had the most beneficial effects on subsequent performance. Consistent with previous research, these results suggest that sleep plays an important role in some, but not all, aspects of athletes' performance and recovery. Future researchers should aim to conduct sleep interventions among different athlete populations, compare results, and further establish guidelines and intervention tools for athletes to address their specific sleep demands and disturbances.
Management of hypertension in actively exercising patients. Implications for drug selection.
Klaus, D
1989-02-01
In general, rises in systolic blood pressure to over 200 mm Hg during exercise with a workload of 100W are regarded as pathological. Excessive exercise blood pressure values are to be expected in principle in all hypertensives. However, there are so far no generally accepted criteria for diagnosis of isolated systolic exercise hypertension (with normal values of resting blood pressure). The incidence of isolated systolic exercise hypertension is estimated to be about 10% of a selected population. In patients with excessive rises in blood pressure during exercise who want to engage actively in sport, general measures (reduction of obesity, restriction of alcohol and salt intake) and endurance training should be recommended initially. For endurance training, sporting activities that involve dynamic exercise are to be recommended (walking, running, mountain hiking, cycling, swimming, cross-country skiing). Activities involving isometric exercise (rowing, diving, tennis) and sport of a competitive nature are not suitable. In moderately severe and severe hypertension (diastolic blood pressure values in excess of 105 mm Hg), sporting activities and endurance training are contraindicated. If the exercise blood pressure values cannot be lowered below 220 mm Hg with the general measures mentioned, pharmacotherapy is to be considered. The drugs of choice for suppressing excessive rises in blood pressure during exercise are beta-blockers. In this group, beta 1-blockers are to be preferred to non-selective beta-blockers because of the metabolic neutrality of the former. beta-Blockers without intrinsic sympathomimetic activity (ISA) lower the blood pressure-pulse rate product more effectively than beta-blockers with ISA. Alternatively, calcium antagonists of the verapamil type and ACE inhibitors can be employed.(ABSTRACT TRUNCATED AT 250 WORDS)
EEG Topographic Mapping of Visual and Kinesthetic Imagery in Swimmers.
Wilson, V E; Dikman, Z; Bird, E I; Williams, J M; Harmison, R; Shaw-Thornton, L; Schwartz, G E
2016-03-01
This study investigated differences in QEEG measures between kinesthetic and visual imagery of a 100-m swim in 36 elite competitive swimmers. Background information and post-trial checks controlled for the modality of imagery, swimming skill level, preferred imagery style, intensity of image and task equality. Measures of EEG relative magnitude in theta, low (7-9 Hz) and high alpha (8-10 Hz), and low and high beta were taken from 19 scalp sites during baseline, visual, and kinesthetic imagery. QEEG magnitudes in the low alpha band during the visual and kinesthetic conditions were attenuated from baseline in low band alpha but no changes were seen in any other bands. Swimmers produced more low alpha EEG magnitude during visual versus kinesthetic imagery. This was interpreted as the swimmers having a greater efficiency at producing visual imagery. Participants who reported a strong intensity versus a weaker feeling of the image (kinesthetic) had less low alpha magnitude, i.e., there was use of more cortical resources, but not for the visual condition. These data suggest that low band (7-9 Hz) alpha distinguishes imagery modalities from baseline, visual imagery requires less cortical resources than kinesthetic imagery, and that intense feelings of swimming requires more brain activity than less intense feelings.
Kinematic hand parameters in front crawl at different paces of swimming.
Samson, Mathias; Monnet, Tony; Bernard, Anthony; Lacouture, Patrick; David, Laurent
2015-11-05
The aim of this study was to investigate the evolution of kinematic hand parameters (sweepback angle, angle of attack, velocity, acceleration and orientation of the hand relative to the absolute coordinate system) throughout an aquatic stroke and to study the possible modifications caused by a variation of the swimming pace. Seventeen competitive swimmers swam at long distance, middle distance and sprint paces. Parameters were calculated from the trajectory of seven markers on the hand measured with an optoelectronic system. Results showed that kinematic hand parameters evolve differently depending on the pace. Angle of attack, sweepback angle, acceleration and orientation of the hand do not vary significantly. The velocity of the hand increases when the pace increases, but only during the less propulsive phases (entry and stretch and downsweep to catch). The more the pace increases and the more the absolute durations of the entry and stretch and downsweep to catch phases decrease. Absolute durations of the insweep and upsweep phases remain constant. During these phases, the propulsive hand forces calculated do not vary significantly when the pace increases. The increase of swimming pace is then explained by the swimmer's capacity to maintain propulsive phases rather than increasing the force generation within each cycle. Copyright © 2015 Elsevier Ltd. All rights reserved.
46 CFR 12.602 - Basic training.
Code of Federal Regulations, 2014 CFR
2014-10-01
...) Swimming while wearing a lifejacket. (v) Keeping afloat without a lifejacket. (2) Fire prevention and... extinguishers. (ii) Extinguishing smaller fires. e.g., electrical fires, oil fires, and propane fires. (iii... firefighting agent in an accommodation room or simulated engine room with fire and heavy smoke. (vii...
Summer Adventure: You Can Make It Happen in Your Community.
ERIC Educational Resources Information Center
Butler, Bill
Summer Adventure, a university-based, full-day, community education program for kindergartners and elementary students is described. The program offers physical and enrichment activities, an "extravaganza," and production and leadership in training activities. The physical activities include golf, swimming, volleyball, and gymnastics. Fitness…
Community Inclusion for Children and Youth with Developmental Disabilities.
ERIC Educational Resources Information Center
Fennick, Ellen; Royle, James
2003-01-01
Activity coaches from university teacher education and health education programs were trained to use individualized accommodations to help six children (ages 6-13) with developmental disabilities participate in community recreation activities. Children participated in swim classes or gymnastics at individualized levels, expressed enjoyment, and…
... muscle breakdown when doing intense exercise, such as competitive sports or military training under unfavorable temperatures( very ... during training. People with SCT who participate in competitive or team sports (i.e. student athletes) should ...
Estimating the energy contribution during single and repeated sprint swimming.
Peyrebrune, M C; Toubekis, A G; Lakomy, H K A; Nevill, M E
2014-04-01
The extent to which aerobic processes contribute to energy supply during short duration sprint swimming is not known. Therefore, the energy contribution to a maximal 30 s fully tethered swim (FTS), and repeated 4 × 30 s high intensity semi-tethered swimming bouts (STS) with 30 s of passive rest at 95% of the 30 s FTS intensity was estimated in eight elite male swimmers. Blood lactate concentration and pH after the 4 × 30 s test were 12.1 ± 3.6 mmol/L and 7.2 ± 0.1, respectively. Accumulated oxygen demand was estimated to be 50.9 ± 9.6 mL/kg and 48.3 ± 8.4, 47.2 ± 8.5, 47.4 ± 8.3, and 45.6 ± 6.8 mL/kg for the 30 s FTS and 4 × 30 s bouts, respectively. Accumulated oxygen uptake was 16.6 ± 3.6 for the 30 s FTS and progressively increased during the 4 × 30 s bouts 12.2 ± 2.1, 21.6 ± 2.5, 22.8 ± 1.8, and 23.5 ± 2.0 mL/kg (P < 0.01). The estimated aerobic contribution therefore was 33 ± 8% for the 30 s FTS and 25 ± 4, 47 ± 9, 49 ± 8, 52 ± 9% for bouts 1-4 during the 4 × 30 s STS test (P < 0.01). The results underline the importance of aerobic energy contribution during single and repeated high intensity swimming, which should be considered when prescribing swimming training sets of this nature. © 2012 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Yuan, Xi; Zhou, Yi-Hong; Huang, Ying-Ping; Guo, Wen-Tao; Johnson, David; Jiang, Qing; Jing, Jin-Jie; Tu, Zhi-Ying
2017-10-01
Chinese sturgeon (Acipenser sinensis) is a critically endangered species. A flume-type respirometer, with video, was used to conduct two consecutive stepped velocity tests at 10, 15, 20, and 25 °C. Extent of recovery was measured after the 60-min recovery period between trials, and the recovery ratio for critical swimming speed (U crit ) averaged 91.88% across temperatures. Temperature (T) effects were determined by comparing U crit , oxygen consumption rate (MO 2 ), and tail beat frequency (TBF) for each temperature. Results from the two trials were compared to determine the effect of exercise. The U crit occurring at 15 °C in both trials was significantly higher than that at 10 and 25 °C (p < 0.05). The U crit was plotted as a function of T and curve-fitting allowed calculation of the optimal swimming temperature 3.28 BL/s at 15.96 °C (trial 1) and 2.98 BL/s at 15.85 °C (trial 2). In trial 1, MO 2 increased rapidly with U, but then declined sharply as swimming speed approached U crit . In trial 2, MO 2 increased more slowly, but continuously, to U crit . TBF was directly proportional to U and the slope (dTBF/dU) for trial 2 was significantly lower than that for trial 1. The inverse slope (tail beats per body length, TB/BL) is a measure of swimming efficiency and the significant difference in slopes implies that the exercise training provided by trial 1 led to a significant increase in swimming efficiency in trial 2.
Saloma, Caesar; Perez, Gay Jane; Gavile, Catherine Ann; Ick-Joson, Jacqueline Judith; Palmes-Saloma, Cynthia
2015-01-01
We study the impact of prior individual training during group emergency evacuation using mice that escape from an enclosed water pool to a dry platform via any of two possible exits. Experimenting with mice avoids serious ethical and legal issues that arise when dealing with unwitting human participants while minimizing concerns regarding the reliability of results obtained from simulated experiments using ‘actors’. First, mice were trained separately and their individual escape times measured over several trials. Mice learned quickly to swim towards an exit–they achieved their fastest escape times within the first four trials. The trained mice were then placed together in the pool and allowed to escape. No two mice were permitted in the pool beforehand and only one could pass through an exit opening at any given time. At first trial, groups of trained mice escaped seven and five times faster than their corresponding control groups of untrained mice at pool occupancy rate ρ of 11.9% and 4%, respectively. Faster evacuation happened because trained mice: (a) had better recognition of the available pool space and took shorter escape routes to an exit, (b) were less likely to form arches that blocked an exit opening, and (c) utilized the two exits efficiently without preference. Trained groups achieved continuous egress without an apparent leader-coordinator (self-organized queuing)—a collective behavior not experienced during individual training. Queuing was unobserved in untrained groups where mice were prone to wall seeking, aimless swimming and/or blind copying that produced circuitous escape routes, biased exit use and clogging. The experiments also reveal that faster and less costly group training at ρ = 4%, yielded an average individual escape time that is comparable with individualized training. However, group training in a more crowded pool (ρ = 11.9%) produced a longer average individual escape time. PMID:25693170
Federal Register 2010, 2011, 2012, 2013, 2014
2012-05-30
... Proposed Information Collection to OMB; Office of Native American Programs (ONAP) Training and Technical.... 552) authorizes HUD to award training and technical assistance contracts on a competitive basis. HUD intends to competitively award training and technical assistance contracts to national and regional...
Schwellnus, Martin; Alonso, Juan-Manuel; Bahr, Roald; Clarsen, Ben; Dijkstra, H Paul; Gabbett, Tim J; Gleeson, Michael; Hutchinson, Mark R; Janse Van Rensburg, Christa; Meeusen, Romain; Orchard, John W; Pluim, Babette M; Raftery, Martin; Budgett, Richard; Engebretsen, Lars
2016-01-01
The modern-day athlete participating in elite sports is exposed to high training loads and increasingly saturated competition calendar. Emerging evidence indicates that inappropriate load management is a significant risk factor for acute illness and the overtraining syndrome. The IOC convened an expert group to review the scientific evidence for the relationship of load—including rapid changes in training and competition load, competition calendar congestion, psychological load and travel—and health outcomes in sport. This paper summarises the results linking load to risk of illness and overtraining in athletes, and provides athletes, coaches and support staff with practical guidelines for appropriate load management to reduce the risk of illness and overtraining in sport. These include guidelines for prescription of training and competition load, as well as for monitoring of training, competition and psychological load, athlete well-being and illness. In the process, urgent research priorities were identified. PMID:27535991
Knechtle, Beat; Bragazzi, Nicola Luigi; König, Stefan; Nikolaidis, Pantelis Theodoros; Wild, Stefanie; Rosemann, Thomas; Rüst, Christoph Alexander
2016-01-01
(1) Background: We investigated the age of swimming champions in all strokes and race distances in World Championships (1994–2013) and Olympic Games (1992–2012); (2) Methods: Changes in age and swimming performance across calendar years for 412 Olympic and world champions were analysed using linear, non-linear, multi-level regression analyses and MultiLayer Perceptron (MLP); (3) Results: The age of peak swimming performance remained stable in most of all race distances for world champions and in all race distances for Olympic champions. Longer (i.e., 200 m and more) race distances were completed by younger (~20 years old for women and ~22 years old for men) champions than shorter (i.e., 50 m and 100 m) race distances (~22 years old for women and ~24 years old for men). There was a sex difference in the age of champions of ~2 years with a mean age of ~21 and ~23 years for women and men, respectively. Swimming performance improved in most race distances for world and Olympic champions with a larger trend of increase in Olympic champions; (4) Conclusion: Swimmers at younger ages (<20 years) may benefit from training and competing in longer race distances (i.e., 200 m and longer) before they change to shorter distances (i.e., 50 m and 100 m) when they become older (>22 years). PMID:29910265
Competition and Market Reform in the Australian VET Sector. Review of Research.
ERIC Educational Resources Information Center
Anderson, Damon
This report examines current knowledge about the nature, development, and consequences of competition and market reform in the Australian vocational education and training (VET) sector. In the process, the policy context and key aspects of the theory and practice of a competitive training market are analyzed. These other topics related to the…
Deaner, Robert O; Lowen, Aaron; Rogers, William; Saksa, Eric
2015-01-01
Sex differences in some preferences and motivations are well established, but it is unclear whether they persist in selective sub-populations, such as expert financial decision makers, top scientists, or elite athletes. We addressed this issue by studying competitiveness in 1,147 varsity intercollegiate distance runners. As expected, across all runners, men reported greater competitiveness with two previously validated instruments, greater competitiveness on a new elite competitiveness scale, and greater training volume, a known correlate of competitiveness. Among faster runners, the sex difference decreased for one measure of competitiveness but did not decrease for the two other competitiveness measures or either measure of training volume. Across NCAA athletic divisions (DI, DII, DIII), the sex difference did not decrease for any competitiveness or training measure. Further analyses showed that these sex differences could not be attributed to women suffering more injuries or facing greater childcare responsibilities. However, women did report greater commitment than men to their academic studies, suggesting a sex difference in priorities. Therefore, policies aiming to provide men and women with equal opportunities to flourish should acknowledge that sex differences in some kinds of preferences and motivation may persist even in selective sub-populations.
Lowen, Aaron; Rogers, William; Saksa, Eric
2015-01-01
Sex differences in some preferences and motivations are well established, but it is unclear whether they persist in selective sub-populations, such as expert financial decision makers, top scientists, or elite athletes. We addressed this issue by studying competitiveness in 1,147 varsity intercollegiate distance runners. As expected, across all runners, men reported greater competitiveness with two previously validated instruments, greater competitiveness on a new elite competitiveness scale, and greater training volume, a known correlate of competitiveness. Among faster runners, the sex difference decreased for one measure of competitiveness but did not decrease for the two other competitiveness measures or either measure of training volume. Across NCAA athletic divisions (DI, DII, DIII), the sex difference did not decrease for any competitiveness or training measure. Further analyses showed that these sex differences could not be attributed to women suffering more injuries or facing greater childcare responsibilities. However, women did report greater commitment than men to their academic studies, suggesting a sex difference in priorities. Therefore, policies aiming to provide men and women with equal opportunities to flourish should acknowledge that sex differences in some kinds of preferences and motivation may persist even in selective sub-populations. PMID:25922790
Aquatic Exercise for the Aged.
ERIC Educational Resources Information Center
Daniel, Michael; And Others
The development and implementation of aquatic exercise programs for the aged are discussed in this paper. Program development includes a discussion of training principles, exercise leadership and the setting up of safe water exercise programs for the participants. The advantages of developing water exercise programs and not swimming programs are…
Crewther, Blair T; Heke, Taati; Keogh, Justin W L
2011-01-01
This study examined the effects of training volume and competition on the salivary cortisol (Sal-C) concentrations of Olympic weightlifters. Male (n = 5) and female (n = 4) Olympic weightlifters provided saliva samples across a 5-week experimental = period. The first aim was to assess the weekly effects of high (≥ 200 sets) and low (≤ 100 sets) training volume on Sal-C. The second aim was to compare Sal-C concentrations and 1 repetition maximum (1RM) performance during 2 simulated and 2 actual competitions. Performance was assessed using the snatch, clean and jerk, and the Olympic total lift. Data from each competition setting were pooled before analysis. There were no significant weekly changes in Sal-C levels (p > 0.05). The actual competitions produced higher (128-130%) Sal-C concentrations (p < 0.001) and superior 1RM lifts (1.9-2.6%) for the clean and jerk, and the Olympic total, than the simulated competitions (p < 0.05). Individual Sal-C concentrations before the simulated competitions were positively correlated to all of the 1RM lifts (r = 0.48-0.49, p < 0.05). In conclusion, actual competitions produced greater Sal-C responses than simulated competitions, and this appeared to benefit the 1RM performance of Olympic weightlifters. Individuals with higher Sal-C concentrations also tended to exhibit superior 1RM lifts during the simulated competitions. Given these findings, greater emphasis should be placed upon the monitoring of C to establish normative values, training standards and to assist with performance prediction.
Prevention of atherosclerosis by Yindan Xinnaotong capsule combined with swimming in rats.
Wang, Jianlu; Wang, Lan; Yang, Hongjun; You, Yun; Xu, Haiyu; Gong, Leilei; Yin, Xiaojie; Wang, Wandan; Gao, Shuangrong; Cheng, Long; Liang, Rixin; Liao, Fulong
2015-04-08
Yindan Xinnaotong capsule has been used for treating cardio-cerebrovascular diseases for several decades in China. Exercise training can protect against the development of atherosclerosis. The aim of the present study is to evaluate the joint effect of YXC and exercise on atherosclerosis in rats. A combined method involving low shear stress and a high-fat diet was used to establish the atherosclerosis model in rats. Partial ligation of the left common carotid artery was performed, and then the rats were divided into 9 treatment groups according to a 3 × 3 factorial design with two factors and three levels for each factor, swimming of 0, 0.5, 1 h daily and YXC administration of 0, 1, 2 g/kg p.o. daily. Next the interventions of swimming and YXC were executed for 8 weeks. After that, blood samples were collected to determine blood viscosity, plasma viscosity, haematocrit (HCT), fibrinogen (FIB), blood lipid profile (including total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C), triglyceride (TG) and high-density lipoprotein-cholesterol (HDL-C)), nitric oxide (NO), 6-keto- prostaglandin (PG) F1α, endothelin (ET) and thromboxane (TX) B2. The common carotid arteries of the rats were harvested to examine pathological changes, wall thickness and circumference, and the expression of SM22αwas assayed via immune-histochemistry. The early pathological changes were observed. The joint effects of YXC and swimming showed significant changes in the examined parameters: (1) decreases in plasma viscosity, blood viscosity and FIB; (2) increases in NO and 6-keto-PGF1α; (3) decreases in ET and TXB2; and (4) decreases in LDL-C and TG. The combination of 2 g/kg YXC and 1 h of swimming led to synergistic decreases in LDL-C and TG. The interactive effect between YXC and swimming was obvious in decreasing wall thickness. Swimming alone was able to up-regulate the expression of SM22α. In conclusion, this study indicates that the combination of YXC and swimming may prevent atherosclerosis through a synergistic effect between YXC and swimming in improving blood circulation, hemorheological parameters, blood lipids levels and the vascular endothelium in rats. The vascular remodeling may be contributed to the prevention effects on AS by up-regulating SM22α.
Injuries and overuse syndromes in competitive and elite bodybuilding.
Siewe, J; Marx, G; Knöll, P; Eysel, P; Zarghooni, K; Graf, M; Herren, C; Sobottke, R; Michael, J
2014-10-01
Competitive bodybuilding is a weightlifting sport similar to powerlifting, strongman competition and Olympic weightlifting, which aims to increase muscle mass, symmetry, and body definition. Although data regarding rates of injury, overuse syndromes and pain during routine training is available for these other disciplines, it is rare for competitive bodybuilding. The aim of this study was to investigate rates of injury, pain during workouts and/or overuse syndromes, as well as the influence of particular intrinsic and external factors. Data was collected using questionnaires from 71 competitive and elite bodybuilders. The information included training routines and prior injuries. Participants were recruited from bodybuilding clubs in Germany. 45.1% of athletes reported symptoms while training. The overall injury rate was computed to be 0.12 injuries per bodybuilder per year (0.24 injuries per 1 000 h of bodybuilding). Athletes over 40 exhibited higher rates of injury (p=0.029). Other investigated parameters showed no effects. Most injuries occurred in the shoulder, elbow, lumbar spine and knee regions. A large proportion of bodybuilders complained of pain not resulting in interruptions of training/competition. The injury rate is low compared to other weightlifting disciplines such as powerlifting, Olympic weightlifting or strongman competition. In comparison to team or contact sports the injury rate is minimal. © Georg Thieme Verlag KG Stuttgart · New York.
Crewther, Blair T; Cook, Christian J
2018-05-01
There is evidence linking women's testosterone (T) to competitive behaviours in sport and exercise. To advance this work, we examined the longitudinal relationships between salivary T (sal-T) and competitiveness in athletic women who differ in training status. Elite (n = 9) and non-elite (n = 21) women athletes were monitored on days 6-8 (follicular phase), 13-15 (ovulatory phase) and 20-22 (Luteal phase) of a menstrual cycle with two repeats. Salivary T levels were assessed before breakfast, followed by two questions (each rated on a 1-7 scale) on competitive desire and training motivation. Using a linear mixed model, we evaluated the menstrual phase and training status effects on each variable, before assessing the within-subject effects of sal-T on competitiveness. Salivary T concentrations were higher at ovulation (effect size [ES] difference = 0.2-1.4), relative to the follicular and luteal phases, with a more marked response among elite women (p < .01). The competitiveness ratings showed similar menstrual-phase variation (ES difference = 0.6-1.0 at ovulation). A positive effect of sal-T on competitiveness emerged in both groups (p < .001), but with different slope patterns (p < .015). Specifically, the elite sal-T relationships with desire to compete (standardized β = 1.147, SE = 0.132) and training motivation (β = 1.195, SE = 0.124) were stronger compared with non-elite women (β = 0.631, SE = 0.114; β = 0.778, SE = 0.114), respectively. Morning sal-T concentrations, competitive desire and training motivation all peaked around ovulation in women athletes. Notably, sal-T availability and its relationship with competitiveness was stronger among high-performing athletes. Our findings confirm menstrual fluctuations in T and competitiveness among naturally-cycling women, with population context as a moderating factor. Copyright © 2018 Elsevier Inc. All rights reserved.
Metzler, R; Kinzel, W; Kanter, I
2000-08-01
Several scenarios of interacting neural networks which are trained either in an identical or in a competitive way are solved analytically. In the case of identical training each perceptron receives the output of its neighbor. The symmetry of the stationary state as well as the sensitivity to the used training algorithm are investigated. Two competitive perceptrons trained on mutually exclusive learning aims and a perceptron which is trained on the opposite of its own output are examined analytically. An ensemble of competitive perceptrons is used as decision-making algorithms in a model of a closed market (El Farol Bar problem or the Minority Game. In this game, a set of agents who have to make a binary decision is considered.); each network is trained on the history of minority decisions. This ensemble of perceptrons relaxes to a stationary state whose performance can be better than random.
NASA Astrophysics Data System (ADS)
Metzler, R.; Kinzel, W.; Kanter, I.
2000-08-01
Several scenarios of interacting neural networks which are trained either in an identical or in a competitive way are solved analytically. In the case of identical training each perceptron receives the output of its neighbor. The symmetry of the stationary state as well as the sensitivity to the used training algorithm are investigated. Two competitive perceptrons trained on mutually exclusive learning aims and a perceptron which is trained on the opposite of its own output are examined analytically. An ensemble of competitive perceptrons is used as decision-making algorithms in a model of a closed market (El Farol Bar problem or the Minority Game. In this game, a set of agents who have to make a binary decision is considered.); each network is trained on the history of minority decisions. This ensemble of perceptrons relaxes to a stationary state whose performance can be better than random.
Machine learning of swimming data via wisdom of crowd and regression analysis.
Xie, Jiang; Xu, Junfu; Nie, Celine; Nie, Qing
2017-04-01
Every performance, in an officially sanctioned meet, by a registered USA swimmer is recorded into an online database with times dating back to 1980. For the first time, statistical analysis and machine learning methods are systematically applied to 4,022,631 swim records. In this study, we investigate performance features for all strokes as a function of age and gender. The variances in performance of males and females for different ages and strokes were studied, and the correlations of performances for different ages were estimated using the Pearson correlation. Regression analysis show the performance trends for both males and females at different ages and suggest critical ages for peak training. Moreover, we assess twelve popular machine learning methods to predict or classify swimmer performance. Each method exhibited different strengths or weaknesses in different cases, indicating no one method could predict well for all strokes. To address this problem, we propose a new method by combining multiple inference methods to derive Wisdom of Crowd Classifier (WoCC). Our simulation experiments demonstrate that the WoCC is a consistent method with better overall prediction accuracy. Our study reveals several new age-dependent trends in swimming and provides an accurate method for classifying and predicting swimming times.
Analysis of speed, stroke rate, and stroke distance for world-class breaststroke swimming.
Garland Fritzdorf, Stephen; Hibbs, Angela; Kleshnev, Valery
2009-02-15
Speed in aquatic locomotion is determined by stroke distance and stroke rate, but it does not always follow that an increase in stroke rate will lead to an increase in speed. Kleshnev (2006) developed a method to evaluate the relationship between speed and stroke rate during rowing - the effective work per stroke. In this case study, the effective work per stroke was determined for a male world-class 100-m breaststroke swimmer for seven races in major championships and compared between: each of the seven races; each quarter within each race; and the best swims of this case study and seven other world-class swimmers. The effective work per stroke was related to race performance, with the fastest race having the highest effective work per stroke and lowest stroke rate, with slower races having low effectiveness and high stroke rate (R(2) = 0.85). The effective work per stroke was reduced in a race as the swimmer fatigued. The within-race standard deviation of effectiveness was lower in fast swims (R(2) = 0.84). This analysis has identified some characteristics of fast swimming: high effectiveness, optimal stroke rate, and a flat effectiveness profile. Training and racing strategies can now be devised to improve performance by increasing the sensitivity of assessment of strengths and weaknesses in individuals.
High-impact sport after hip resurfacing: The Ironman triathlon.
Girard, J; Lons, A; Pommepuy, T; Isida, R; Benad, K; Putman, S
2017-09-01
Returning to high-impact sport is an increasingly frequent functional demand following hip replacement. The literature, however, is sparse on the subject and nonexistent regarding triathlon. We therefore conducted a retrospective study of hip resurfacing in triathlon players, to determine: (1) whether it is possible to return to this kind of sport; (2) if so, whether it is possible to return to the same level; and (3) how a resurfaced hip behaves under these conditions. Hip resurfacing allows return to competition level in long-distance triathlon. A single-center single-operator retrospective study included patients undergoing hip resurfacing with the Conserve Plus implant inserted through a posterolateral approach, who had ceased long-distance triathlon practice due to osteoarthritis of the hip. Fifty-one of the 1688 patients undergoing resurfacing during the inclusion period were long-distance triathlon players. The series comprised 48 patients: 51 implants; 43 male, 5 female; mean age, 44.8 years (range, 28.2-58.9 years). At a mean 4.7 years' follow-up (range, 2.2-7.6 years), all clinical scores showed significant improvement; Merle d'Aubigné and Harris scores rose respectively from 12.3 (5-16) and 42 (37-56) preoperatively to 17.5 (13-18) and 93.2 (73-100) (P<0.001). There were no cases of dislocation or implant revision. Forty-five patients returned to sport (94%). Rates of return to swimming, cycling and running were respectively 38/48 (79%), 41/48 (85%) and 33/48 (69%). Preoperatively, all patients had taken part in at least 1 competition: 29 with distance=70.3km and 19 with distance=140.6km. At follow-up, 28 patients had taken part in an Ironman competition: 21 with distance=70.3km and 7 with distance=140.6km. Mean competition performance did not differ between pre and postoperative periods. Return-to-sport rates were good following hip resurfacing. Non-impact sports (swimming, cycling) predominated postoperatively, whereas the rate of impact sport (running) diminished. Return to competition-level sport (extreme triathlon) was possible for 28/48 patients (58%). Implant survival seemed unaffected by this high-impact sports activity at a mean 4.7 years' follow-up. IV, retrospective, non-controlled. Copyright © 2017 Elsevier Masson SAS. All rights reserved.
The 'Negligence' Buck Stops with You!
ERIC Educational Resources Information Center
Stern, James
1982-01-01
The owner or operator of a public swimming pool is legally responsible for the health and safety of patrons who use the pool. Legal cases resulting from negligence include judgements against the owner due to: lack of lifeguard training, inattentiveness on the part of lifeguards, improper depth markings, water containing infectious organisms, and…
Fitness for Individuals Who Are Visually Impaired or Deafblind.
ERIC Educational Resources Information Center
Lieberman, Lauren J.
2002-01-01
This article discusses the importance of daily physical activity and examples of how individuals who are visually impaired or deaf-blind can access fitness. It describes techniques for running, bicycling, swimming, exercise training in a health club, aerobics, and fitness at home (jumping rope, yoga, and basketball). (Contains references.) (CR)
Exercise-Induced Changes in Metabolic Resposes to Infection in Trained Rats.
1981-07-20
superimposed on fasting reduced it in sedentary rats (24). Swimming amplified fasting ketosis and diminished infection ketonemia and markedly decreased...Ketone body metabolism in the ketosis of starvation and alloxan diabetes. J. Biol. Chem. 245:4382-4390, 1970. 22. MOSES, L. E. Determination of oxygen
ERIC Educational Resources Information Center
Noyelle, Thierry; Bailey, Thomas
Changing employer-based training represents one strategy that U.S. firms are adopting to confront recent transformations in the global economy. The new competitive conditions place new and different demands on workers, more of whom are being called upon to use technical, conceptual, and communications skills. Approaches to training in particular…
Training Workers for the Factory of the Future.
ERIC Educational Resources Information Center
Clancy, J. Anthony
1989-01-01
In the factory of the future, emphasis on quality and increased productivity creates a competitive advantage. People and computers work together in all major activities. Training is a major factor in creating that competitive advantage. (JOW)
Let's dance--feel better! Mood changes following dancing in different situations.
Zajenkowski, Marcin; Jankowski, Konrad S; Kołata, Daria
2015-01-01
In the present study, we examined mood changes following dancing. Previous works suggested that contextual factors may influence affective states; it has been shown that changes in mood following competition differ from those following recreational exercise. The study has been conducted in Warsaw, Poland. Mood was assessed before and after dance activity in three groups of ballroom dancers: recreational (n = 32) and competitive (n = 38) dancers doing ordinary training and competitive dancers taking part in a dance competition (n = 35). We observed a moderately positive change in recreational dancers doing ordinary training; they reported higher energetic arousal (EA) and hedonic tone (HT) and lower tense arousal (TA) after dance activity. In comparison dancers taking part in a competition were higher on TA before dancing and felt less pleasure after dancing than recreational and competitive dancers doing ordinary training; HT, TA and EA moderately decreased during competition. In general, the current study suggests that dance can elicit changes in mood; however, situational context has to be taken into consideration when explaining the influence of dance on mood.
Balsalobre-Fernández, Carlos; Tejero-González, Carlos Mª; del Campo-Vecino, Juan
2014-01-01
Purpose Monitoring training from a multifactorial point of view is of great importance in elite endurance athletes. This study aims to analyze the relationships between indicators of training load, hormonal status and neuromuscular performance, and to compare these values with competition performance, in elite middle and long-distance runners. Method Fifteen elite middle and long-distance runners (12 men, 3 women; age = 26.3±5.1 yrs) were measured for training volume, training zone and session rate of perceived exertion (RPE) (daily), countermovement jump (CMJ) and salivary free cortisol (weekly) for 39 weeks (i.e., the whole season). Competition performance was also observed throughout the study, registering the season best and worst competitions. Results Season average salivary free cortisol concentrations correlate significantly with CMJ (r = −0.777) and RPE (r = 0.551). Also, weekly averages of CMJ significantly correlates with RPE (r = −0.426), distance run (r = −0.593, p<0.001) and training zone (r = 0.437, p<0.05). Finally, it was found that the CMJ (+8.5%, g = 0.65) and the RPE (−17.6%, g = 0.94) measured the week before the best competition performance of the season were significantly different compared with the measurement conducted the week before the season’s worst competition performance. Conclusions Monitoring weekly measurements of CMJ and RPE could be recommended to control training process of such athletes in a non-invasive, field-based, systematic way. PMID:25153137
Yusifov, Rashad
2018-01-01
Abstract For routine behavioral tasks, mice predominantly rely on olfactory cues and tactile information. In contrast, their visual capabilities appear rather restricted, raising the question whether they can improve if vision gets more behaviorally relevant. We therefore performed long-term training using the visual water task (VWT): adult standard cage (SC)-raised mice were trained to swim toward a rewarded grating stimulus so that using visual information avoided excessive swimming toward nonrewarded stimuli. Indeed, and in contrast to old mice raised in a generally enriched environment (Greifzu et al., 2016), long-term VWT training increased visual acuity (VA) on average by more than 30% to 0.82 cycles per degree (cyc/deg). In an individual animal, VA even increased to 1.49 cyc/deg, i.e., beyond the rat range of VAs. Since visual experience enhances the spatial frequency threshold of the optomotor (OPT) reflex of the open eye after monocular deprivation (MD), we also quantified monocular vision after VWT training. Monocular VA did not increase reliably, and eye reopening did not initiate a decline to pre-MD values as observed by optomotry; VA values rather increased by continued VWT training. Thus, optomotry and VWT measure different parameters of mouse spatial vision. Finally, we tested whether long-term MD induced ocular dominance (OD) plasticity in the visual cortex of adult [postnatal day (P)162–P182] SC-raised mice. This was indeed the case: 40–50 days of MD induced OD shifts toward the open eye in both VWT-trained and, surprisingly, also in age-matched mice without VWT training. These data indicate that (1) long-term VWT training increases adult mouse VA, and (2) long-term MD induces OD shifts also in adult SC-raised mice. PMID:29379877
The Size and Scope of Collegiate Athletic Training Facilities and Staffing.
Gallucci, Andrew R; Petersen, Jeffrey C
2017-08-01
Athletic training facilities have been described in terms of general design concepts and from operational perspectives. However, the size and scope of athletic training facilities, along with staffing at different levels of intercollegiate competition, have not been quantified. To define the size and scope of athletic training facilities and staffing levels at various levels of intercollegiate competition. To determine if differences existed in facilities (eg, number of facilities, size of facilities) and staffing (eg, full time, part time) based on the level of intercollegiate competition. Cross-sectional study. Web-based survey. Athletic trainers (ATs) who were knowledgeable about the size and scope of athletic training programs. Athletic training facility size in square footage; the AT's overall facility satisfaction; athletic training facility component spaces, including satellite facilities, game-day facilities, offices, and storage areas; and staffing levels, including full-time ATs, part-time ATs, and undergraduate students. The survey was completed by 478 ATs (response rate = 38.7%) from all levels of competition. Sample means for facilities were 3124.7 ± 4425 ft 2 (290.3 ± 411 m 2 ) for the central athletic training facility, 1013 ± 1521 ft 2 (94 ± 141 m 2 ) for satellite athletic training facilities, 1272 ± 1334 ft 2 (118 ± 124 m 2 ) for game-day athletic training facilities, 388 ± 575 ft 2 (36 ± 53 m 2 ) for athletic training offices, and 424 ± 884 ft 2 (39 ± 82 m 2 ) for storage space. Sample staffing means were 3.8 ± 2.5 full-time ATs, 1.6 ± 2.5 part-time ATs, 25 ± 17.6 athletic training students, and 6.8 ± 7.2 work-study students. Division I schools had greater resources in multiple categories (P < .001). Differences among other levels of competition were not as well defined. Expansion or renovation of facilities in recent years was common, and almost half of ATs reported that upgrades have been approved for the near future. This study provides benchmark descriptive data on athletic training staffing and facilities. The results (1) suggest that the ATs were satisfied with their facilities and (2) highlight the differences in resources among competition levels.
Soligard, Torbjørn; Schwellnus, Martin; Alonso, Juan-Manuel; Bahr, Roald; Clarsen, Ben; Dijkstra, H Paul; Gabbett, Tim; Gleeson, Michael; Hägglund, Martin; Hutchinson, Mark R; Janse van Rensburg, Christa; Khan, Karim M; Meeusen, Romain; Orchard, John W; Pluim, Babette M; Raftery, Martin; Budgett, Richard; Engebretsen, Lars
2016-09-01
Athletes participating in elite sports are exposed to high training loads and increasingly saturated competition calendars. Emerging evidence indicates that poor load management is a major risk factor for injury. The International Olympic Committee convened an expert group to review the scientific evidence for the relationship of load (defined broadly to include rapid changes in training and competition load, competition calendar congestion, psychological load and travel) and health outcomes in sport. We summarise the results linking load to risk of injury in athletes, and provide athletes, coaches and support staff with practical guidelines to manage load in sport. This consensus statement includes guidelines for (1) prescription of training and competition load, as well as for (2) monitoring of training, competition and psychological load, athlete well-being and injury. In the process, we identified research priorities. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
Schwellnus, Martin; Soligard, Torbjørn; Alonso, Juan-Manuel; Bahr, Roald; Clarsen, Ben; Dijkstra, H Paul; Gabbett, Tim J; Gleeson, Michael; Hägglund, Martin; Hutchinson, Mark R; Janse Van Rensburg, Christa; Meeusen, Romain; Orchard, John W; Pluim, Babette M; Raftery, Martin; Budgett, Richard; Engebretsen, Lars
2016-09-01
The modern-day athlete participating in elite sports is exposed to high training loads and increasingly saturated competition calendar. Emerging evidence indicates that inappropriate load management is a significant risk factor for acute illness and the overtraining syndrome. The IOC convened an expert group to review the scientific evidence for the relationship of load-including rapid changes in training and competition load, competition calendar congestion, psychological load and travel-and health outcomes in sport. This paper summarises the results linking load to risk of illness and overtraining in athletes, and provides athletes, coaches and support staff with practical guidelines for appropriate load management to reduce the risk of illness and overtraining in sport. These include guidelines for prescription of training and competition load, as well as for monitoring of training, competition and psychological load, athlete well-being and illness. In the process, urgent research priorities were identified. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
Effect of fastskin suits on performance, drag, and energy cost of swimming.
Chatard, Jean-Claude; Wilson, Barry
2008-06-01
To investigate the effect of fastskin suits on 25- to 800-m performances, drag, and energy cost of swimming. The performances, stroke rate and distance per stroke, were measured for 14 competitive swimmers in a 25-m pool, when wearing a normal suit (N) and when wearing a full-body suit (FB) or a waist-to-ankle suit (L). Passive drag, oxygen uptake, blood lactate, and the perceived exertion were measured in a flume. There was a 3.2% +/- 2.4% performance benefit for all subjects over the six distances covered at maximal speed wearing FB and L when compared with N. When wearing L, the gain was significantly lower (1.8% +/- 2.5%, P < 0.01) than when wearing FB compared with N. The exercise perception was significantly lower when wearing FB than N, whereas there was no statistical difference when wearing L. The distance per stroke was significantly higher when wearing FB and L, whereas the differences in stroke rate were not statistically significant. There was a significant reduction in drag when wearing FB and L of 6.2% +/- 7.9% and 4.7% +/- 4.4%, respectively (P < 0.01), whereas the energy cost of swimming was significantly reduced when wearing FB and L by 4.5% +/- 5.4% and 5.5% +/- 3.1%, respectively (P < 0.01). However, the differences between FB and L were not statistically significant for drag and oxygen uptake. FB and L significantly reduced passive drag, and this was associated with a decreased energy cost of submaximal swimming and an increased distance per stroke, at the same stroke rates, and reduced freestyle performance time.
Emami, Ali; Tofighi, Asghar; Asri-Rezaei, Siamak; Bazargani-Gilani, Behnaz
2018-02-01
Strenuous physical exercise and hyperthermia may paradoxically induce oxidative stress and adverse effects on myocardial function. The purpose of this study was to investigate the effect of 14-d coenzyme Q10 (CoQ10) supplementation and pre-cooling on serum creatine kinase-MB (CK-MB), cardiac Troponin I (cTnI), myoglobin (Mb), lactate dehydrogenase (LD), total antioxidant capacity (TAC), lipid peroxidation (LPO) and CoQ10 concentration in elite swimmers. In total, thirty-six healthy males (mean age 17 (sd 1) years) were randomly selected and divided into four groups of supplementation, supplementation with pre-cooling, pre-cooling and control. During an eighteen-session protocol in the morning and evening, subjects attended speed and endurance swimming training sessions for 5 km in each session. Blood sampling was done before (two stages) and after (two stages) administration of CoQ10 and pre-cooling. ANCOVA and repeated measurement tests with Bonferroni post hoc test were used for the statistical analysis of the data. There was no significant statistical difference among groups for the levels of CK-MB, cTnI, Mb, LD, TAC, LPO and CoQ10 at the presampling (stages 1 and 2) (P>0·05). However, pre-cooling and control groups show a significant increase in the levels of CK-MB, cTnI, Mb, LD and LPO compared with the supplementation and supplementation with pre-cooling groups in the post-sampling (stages 1 and 2) (P<0·05), except for the TAC and CoQ10. Consequently, CoQ10 supplementation prevents adverse changes of myocardial damage and oxidative stress during swimming competition phase. Meanwhile, the pre-cooling strategy individually has no desired effect on the levels of CK-MB, cTnI, Mb, LD, LPO, TAC and CoQ10.
Swimming Three Ice Miles within Fifteen Hours.
Stjepanovic, Mirko; Nikolaidis, Pantelis T.; Knechtle, Beat
2017-08-31
Ice Mile swimming (1608 m in water of below 5 °Celsius) is becoming increasingly popular. This case study aimed to identify body core temperature and selected haematological and biochemical parameters before and after repeated Ice Miles. An experienced ice swimmer completed three consecutive Ice Miles within 15 h. Swim times, body core temperatures, and selected urinary and haematological parameters were recorded. Body core temperature reached its maximum between 5, 8 and 15 min after immersion (37.7°C, 38.1°C, and 38.0°C, respectively). The swimmer suffered hypothermia during the first Ice Mile (35.4°C) and body core temperature dropped furthermore to 34.5°C during recovery after the first Ice Mile. He developed a metabolic acidosis in both the first and the last Ice Mile (pH 7.31 and pH 7.34, respectively). We observed hyperkalaemia ([K⁺] > 5.5 mM) after the second Ice Mile (6.9 mM). This was followed by a drop in [K⁺] to3.7 mM after the third Ice Mile. Anticipatory thermogenesis (i.e. an initial increase of body core temperature after immersion in ice cold water) seems to be a physiological response in a trained athlete. The results suggest that swimming in ice-cold water leads to a metabolic acidosis, which the swimmer compensates with hyperventilation (i.e. leading to respiratory alkalosis). The shift of serum [K⁺] could increase the risk of a cardiac arrhythmia. Further studies addressing the physiology and potential risks of Ice Mile swimming are required to substantiate this finding.
Exercise counteracts fatty liver disease in rats fed on fructose-rich diet
2010-01-01
Background This study aimed to analyze the effects of exercise at the aerobic/anaerobic transition on the markers of non-alcoholic fatty liver disease (NAFLD), insulin sensitivity and the blood chemistry of rats kept on a fructose-rich diet. Methods We separated 48 Wistar rats into two groups according to diet: a control group (balanced diet AIN-93 G) and a fructose-rich diet group (60% fructose). The animals were tested for maximal lactate-steady state (MLSS) in order to identify the aerobic/anaerobic metabolic transition during swimming exercises at 28 and 90 days of age. One third of the animals of each group were submitted to swimming training at an intensity equivalent to the individual MLSS for 1 hours/day, 5 days/week from 28 to 120 days (early protocol). Another third were submitted to the training from 90 to 120 days (late protocol), and the others remained sedentary. The main assays performed included an insulin tolerance test (ITT) and tests of serum alanine aminotransferase [ALT] and aspartate aminotransferase [AST] activities, serum triglyceride concentrations [TG] and liver total lipid concentrations. Results The fructose-fed rats showed decreased insulin sensitivity, and the late-exercise training protocol counteracted this alteration. There was no difference between the groups in levels of serum ALT, whereas AST and liver lipids increased in the fructose-fed sedentary group when compared with the other groups. Serum triglycerides concentrations were higher in the fructose-fed trained groups when compared with the corresponding control group. Conclusions The late-training protocol was effective in restoring insulin sensitivity to acceptable standards. Considering the markers here evaluated, both training protocols were successful in preventing the emergence of non-alcoholic fatty liver status disease. PMID:20946638
ERIC Educational Resources Information Center
Bergeron, Pierrette; Hiller, Christine A.
2002-01-01
Reviews the evolution of competitive intelligence since 1994, including terminology and definitions and analytical techniques. Addresses the issue of ethics; explores how information technology supports the competitive intelligence process; and discusses education and training opportunities for competitive intelligence, including core competencies…
Metabolic predictors of middle-distance swimming performance.
Ribeiro, J P; Cadavid, E; Baena, J; Monsalvete, E; Barna, A; De Rose, E H
1990-09-01
To evaluate the capacity of different metabolic indices to predict performance in middle distance swimming, 15 competitive swimmers performed a submaximal and a maximal 400 metres freestyle swimming event. Expired gases were collected in Douglas bags immediately after the events for the determination of VO2 max. Arterialized blood samples were collected for the determination of maximal blood lactate concentration and the velocity corresponding to blood lactate concentration of 4 mM. The results demonstrated (means +/- SD): maximal velocity of 1.44 +/- 0.05 m.s-1; velocity at 85 percent of VO2 max of 1.36 +/- 0.04 m.s-1; velocity at 4 mM of 1.32 +/- 0.04 m.s-1; VO2 max of 3.47 +/- 0.5 l.min-1; maximal blood lactate concentration of 11.8 +/- 2.5 mM. Multiple regression analysis relating metabolic indices and maximal velocity demonstrated that only velocity at 85 percent of VO2 max (r2 = 0.81) and velocity at 4 mM (r2 = 0.79) were significant predictors. Thus, 79 percent of the variance in the performance of 400 m freestyle can be accounted for the velocity at 85 percent of VO2 max or the velocity at 4 mM. The success in this event seems to depend on the swimmer's capacity to achieve higher velocities with lower blood lactate levels and/or utilizing a lower percentage of their VO2 max.
Parkkali, S; Joosten, R; Fanoy, E; Pijnacker, R; VAN Beek, J; Brandwagt, D; VAN Pelt, W
2017-07-01
On 12 July 2015, a triathlon competition with 900 participants took place in Utrecht, the Netherlands. An outbreak investigation was initiated after 56 participants reported health complaints. An online questionnaire was sent to 700 participants. Stool specimens from six participants and four water specimens were collected from the swimming location. A total of 239 participants completed the questionnaire (response rate: 34%), 73 (31%) of them met the case definition for acute gastrointestinal illness (AGI). A total of 67% of the respondents were male and the median age was 38 years. Almost half (42%) of swimmers reported health complaints. Consumption of energy drinks and ingesting ⩾3 mouthfuls of canal water were identified as risk factors for AGI among swimmers only (adjusted relative risks (aRR) 1·6; 95% confidence intervals (CI) 1·0-2·5 and aRR 2·6; 95% CI 1·5-4·8). The collected water specimens tested positive for norovirus genogroup I and rotavirus and stool specimens tested positive for norovirus genogroup II. Our findings indicate that the outbreak could have been caused by exposure to norovirus during swimming. Swimmers should get information about the health risks for making an informed choice about participating. For future events, the organisers decided to change the swimming location from a canal to a recreational lake.
ERIC Educational Resources Information Center
Smith, Joy Selby
This paper examines the implications of the Report of the Independent Committee of Inquiry into a national competition policy (the Hilmer Report) for the vocational education and training system in Australia. It identifies issues of importance for training markets and points of strategic intervention to facilitate the development of more open and…
ERIC Educational Resources Information Center
Congress of the U.S., Washington, DC. House Committee on Education and Labor.
This congressional report contains testimony pertinent to the passage of the School Improvement Act of 1987 and the Education and Training for American Competitiveness Act of 1987. Testimony by representatives of the following agencies and organizations is included in the report: New York University; the United Steelworkers of America; the…
Training at altitude in practice.
Dick, F W
1992-10-01
There can be little doubt that training at altitude is fundamental to preparing an athlete for competition at altitude. However the value of training at altitude for competition at sea level appears on the one hand to lack total acceptance amongst sports scientists; and on the other to hold some cloak of mystery for coaches who have yet to enjoy first hand experience. The fact is that very few endurance athletes will ignore the critical edge which altitude training affords. Each fraction of a percentage of performance advantage gained through methods which are within the rules of fair play in sport, may shift the balance between failure and achievement. Moreover, there is growing support for application of training at altitude for speed-related disciplines. This paper aims to demystify the subject by dealing with practical aspects of training at altitude. Such aspects include a checklist of what should and should not be done at altitude, when to use altitude relative to target competitions, and specific training examples.
Hutzler, Yeshayahu; Oz, Mali; Barak, Sharon
2013-07-01
Based on social-learning and self-determination motivational theories, the purpose of this study was to determine the sources of motivation in youth and young adults with intellectual disability (ID) who participate in Special Olympics (SO) competitions and those of typically developed (TD) age- and activity-matched athletes. A convenience sample of 63 SO (25 females and 38 males) and 59 TD (16 females and 43 males) athletes was retrieved through communication with local club coaches. Three sub-groups of SO athletes were identified based on disability, including non specified intellectual disability (NSID=39), Down syndrome (DS=17), and Autism (Aut=7). Mean SO and TD athlete ages were 20.35 (SD=7) and 18.8 (SD=8), respectively. For analysis purposes four age groups were created (<15, 15-17, 18-20, >20 years). Participants completed the 13-item, two-factor Task and Ego Orientation in Sport Questionnaire (TEOSQ) and a 16-item four-factor abridged version of the Sport Motivation Scale (SMS). SO and TD athletes were active in swimming (54 and 48, respectively) and basketball (9 and 11, respectively). Groups with and without ID were compared by means of t-tests in the dichotomized variables gender and activity, as well as by 1-way ANOVA with Tukey HSD post hoc comparisons across disability and age groups. Gender distribution was the same in both groups. Participants with DS and NSID scored significantly higher than TD athletes in most motivational scales. Participants with ID increased their external motivation with increasing age, while a reversed pattern was observed in TD. In summary, significant differences between motivational patterns of SO athletes with ID and TD athletes can be observed. These differences should be considered when developing training and competition programs. Copyright © 2013 Elsevier Ltd. All rights reserved.
Sport, Health, Fitness and Dance. AAHPER Research Consortium Symposium Papers.
ERIC Educational Resources Information Center
Corbin, Charles B., Ed.
This collection of symposium papers provides current synthesis of research in the field of physical education and health. In this volume the physiological aspects of physical activities are discussed. The effects of chronic heavy physical training in swimming are examined, comparing age groups and males and females. Stress factors are also…
40 CFR 35.661 - Competitive process.
Code of Federal Regulations, 2010 CFR
2010-07-01
... training in source reduction techniques. Such training may be provided through local engineering schools or... 40 Protection of Environment 1 2010-07-01 2010-07-01 false Competitive process. 35.661 Section 35.661 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY GRANTS AND OTHER FEDERAL ASSISTANCE...
Gómez-Bruton, A; González-Agüero, A; Matute-Llorente, A; Julián, C; Lozano-Berges, G; Gómez-Cabello, A; Casajús, J A; Vicente-Rodríguez, G
2017-12-01
Swimming has little effect on bone mass. Therefore, adolescent swimmers should complement their water training with a short and intense weight-bearing training, aiming to increase their bone acquisition. Forty swimmers performed a six-month whole-body vibration (WBV) training. WBV had no effect on adolescent swimmers' bone mass or lean mass. The aims of the present study were to evaluate the effects of a whole-body vibration (WBV) intervention on bone mineral density (BMD), bone mineral content (BMC) and lean mass (LM) in adolescent swimmers. Forty male and female adolescent swimmers (VIB; mean age 14.2 ± 1.9 years) completed the WBV protocol that consisted of 15 min of training 3 days per week during a 6-month period (ranging from 3.6 to 11.6 g), while 23 swimmers (SWI; mean age 15.0 ± 2.2 years) continued with their regular swimming training alone. VIB were divided into tertiles according to training compliance in order to evaluate if any dose-effect relation existed. BMD, BMC and LM were measured longitudinally by dual energy X-ray at the whole body, lumbar-spine and hip. No group by time interactions and no differences in change percentage were found for BMD, BMC or LM in any of the measured variables. The mean change percentage of the subtotal body (whole body minus the head) for VIB and SWI, respectively, was 2.3 vs. 2.4% for BMD, 5.7 vs 5.7% for BMC and 7.3 vs. 8.0% for lean mass. Moreover, no indication for dose-response was observed. The proposed WBV protocol had no effect on BMD, BMC and LM in adolescent swimmers. Other types of training should be used in this population to improve both bone and lean mass.
Malin, David H; Schaar, Krystal L; Izygon, Jonathan J; Nghiem, Duyen M; Jabitta, Sikirat Y; Henceroth, Mallori M; Chang, Yu-Hsuan; Daggett, Jenny M; Ward, Christopher P
2015-08-01
The Morris water maze is routinely used to explore neurobiological mechanisms of working memory. Humans can often acquire working memory relevant to performing a task by mere sensory observation, without having to actually perform the task followed by reinforcement. This can be modeled in the water maze through direct placement of a rat on the escape platform so that it can observe the location, and then assessing the subject's performance in swimming back to the platform. However, direct placement procedures have hardly been studied for two decades, reflecting a controversy about whether direct placement resulted in sufficiently rapid and direct swims back to the platform. In the present study, utilizing revised training methods, a more comprehensive measure of trajectory directness, a more rigorous sham-trained control procedure and an optimal placement-test interval, rats swam almost directly back to the platform in under 4s, significantly more quickly and directly than sham-trained subjects. Muscarinic cholinergic mechanisms, which are inactivated by scopolamine, are essential to memory for standard learning paradigms in the water maze. This experiment determined whether this would also be true for latent learning. ANOVA revealed significant negative effects of scopolamine on both speed and accuracy of trajectory, as well as significant positive effects of direct placement training vs. sham-training. In a probe trial, placement-trained animals without scopolamine spent significantly more time and path length in the target quadrant than trained rats with scopolamine and sham-trained rats without scopolamine. Scopolamine impairments are likely due to effects on memory, since the same dose had little effect on performance with a visible platform. The revised direct placement model offers a means of further comparing the neural mechanisms of latent learning with those of standard instrumental learning. Copyright © 2015 Elsevier Inc. All rights reserved.
Marti, B
1992-04-07
The relation between physical exercise and blood pressure as well as the risk of hypertension has been investigated extensively during recent years. Cross-sectional studies on exercising and physically fit subjects have shown that endurance capacity (i. e. maximum aerobic capacity) is inversely related to resting blood pressure. However, not all physical activities are associated with lower blood pressure levels; e.g. swimming, weight lifting and competitive cross-country skiing were found to be related to elevated blood pressure values in some studies. Population-based investigations reveal a trend towards lower blood pressure values in physically habitually active persons, with the difference between active and inactive subjects not exceeding 5 mmHg. Three epidemiological cohort studies have consistently demonstrated that sedentary, unfit persons have a 20 to 50% higher prospective risk of hypertension, as compared to exercising, physically fit persons. Some intervention studies with normotensive subjects show a reduction in resting blood pressure of 5 to 10 mmHg at best after several months of aerobic training, while other studies show no effect. At least two factors could be responsible for these somewhat inconsistent observations: 1. exercise intensity may act as an 'effect modifier', since vigorous to maximally hard exercise rather increases than lowers resting blood pressure, 2. in statistical analysis on the effect of physical training on blood pressure, it is crucial whether concomitant changes in body weight and body composition are taken into account: any adjustment for changes in body composition will substantially reduce the magnitude of 'exercise-induced' reductions in blood pressure.(ABSTRACT TRUNCATED AT 250 WORDS)
Bencke, J; Damsgaard, R; Saekmose, A; Jørgensen, P; Jørgensen, K; Klausen, K
2002-06-01
The aim of the present investigation was to study the possible effects of specificity of training on muscle strength and anaerobic power in children from different sports and at different performance levels in relation to growth and maturation status. Hundred and eighty-four children of both gender participating either in swimming, tennis, team handball or gymnastics were recruited from the best clubs in Denmark. Within each sport, the coach had divided the children into an elite (E) and non-elite (NE) group according to performance level and talent. Tanner stage assessment and body weight and height measurements were performed by a physician. The anaerobic performances were assessed by Wingate tests and jumping performance in squat jump (SJ), countermovement jump (CMJ) and drop jump (DJ) from two heights. Most of the differences between groups in Wingate performance disappeared when the data were normalised to body mass. The gymnasts were the best jumpers and their superiority were increased in the more complex motor coordination tasks like DJ. The results may indicate some influence of training specificity, especially on the more complex motor tasks as DJ and there may be an effect of training before puberty. The performance in the less complex motor tasks like cycling and SJ and CMJ may also be influenced by specific training, but not to the same extent, and heritance may be an important factor for performance in these anaerobic tasks.
A Review of Player Monitoring Approaches in Basketball: Current Trends and Future Directions.
Fox, Jordan L; Scanlan, Aaron T; Stanton, Robert
2017-07-01
Fox, JL, Scanlan, AT, and Stanton, R. A review of player monitoring approaches in basketball: current trends and future directions. J Strength Cond Res 31(7): 2021-2029, 2017-Effective monitoring of players in team sports such as basketball requires an understanding of the external demands and internal responses, as they relate to training phases and competition. Monitoring of external demands and internal responses allows coaching staff to determine the dose-response associated with the imposed training load (TL), and subsequently, if players are adequately prepared for competition. This review discusses measures reported in the literature for monitoring the external demands and internal responses of basketball players during training and competition. The external demands of training and competition were primarily monitored using time-motion analysis, with limited use of microtechnology being reported. Internal responses during training were typically measured using hematological markers, heart rate, various TL models, and perceptual responses such as rating of perceived exertion (RPE). Heart rate was the most commonly reported indicator of internal responses during competition with limited reporting of hematological markers or RPE. These findings show a large discrepancy between the reporting of external and internal measures and training and competition demands. Microsensors, however, may be a practical and convenient method of player monitoring in basketball to overcome the limitations associated with current approaches while allowing for external demands and internal responses to be recorded simultaneously. The triaxial accelerometers of microsensors seem well suited for basketball and warrant validation to definitively determine their place in the monitoring of basketball players. Coaching staff should make use of this technology by tracking individual player responses across the annual plan and using real-time monitoring to minimize factors such as fatigue and injury risk.
Training practices and ergogenic aids used by male bodybuilders.
Hackett, Daniel A; Johnson, Nathan A; Chow, Chin-Moi
2013-06-01
Bodybuilding involves performing a series of poses on stage where the competitor is judged on aesthetic muscular appearance. The purpose of this study was to describe training practices and ergogenic aids used by competitive bodybuilders and to determine whether training practices comply with current recommendations for muscular hypertrophy. A web-based survey was completed by 127 competitive male bodybuilders. The results showed that during the off-season phase of training (OFF), the majority of respondents performed 3-6 sets per exercise (95.3%), 7-12 repetition maximum (RM) per set (77.0%), and 61- to 120-seconds recovery between sets and exercises (68.6%). However, training practices changed 6 weeks before competition (PRE), where there was an increased number of respondents who reported undertaking 3-4 sets per exercise at the expense of 5-6 sets per exercise (p < 0.001), an increase in the number reporting 10-15RM per set from 7-9RM per set (p < 0.001), and an increase in the number reporting 30-60 seconds vs. 61-180 seconds recovery between sets and exercises (p < 0.001). Anabolic steroid use was high among respondents competing in amateur competitions (56 of 73 respondents), whereas dietary supplementation was used by all respondents. The findings of this study demonstrate that competitive bodybuilders comply with current resistance exercise recommendations for muscular hypertrophy; however, these changed before competition during which there is a reduction resistance training volume and intensity. This alteration, in addition to an increase in aerobic exercise volume, is purportedly used to increase muscle definition. However, these practices may increase the risk of muscle mass loss in natural compared with amateur bodybuilders who reportedly use drugs known to preserve muscle mass.
Fowler, Peter; Duffield, Rob; Waterson, Adam; Vaile, Joanna
2015-07-01
The current study examined the acute and longitudinal effects of regular away travel on training load (TL), player wellness, and injury surrounding competitive football (soccer) matches. Eighteen male professional football players, representing a team competing in the highest national competition in Australia, volunteered to participate in the study. Training loads, player wellness and injury incidence, rate, severity, and type, together with the activity at the time of injury, were recorded on the day before, the day of, and for 4 d after each of the 27 matches of the 2012-13 season. This included 14 home and 13 away matches, further subdivided based on the midpoint of the season into early (1-13) and late competition (14-27) phases. While TLs were significantly greater on day 3 at home compared with away during the early competition phase (P=.03), no other significant effects of match location were identified (P>.05). Total TL and mean wellness over the 6 d surrounding matches and TL on day 3 were significantly reduced during the late compared with the early competition phase at home and away (P<.05). Although not significantly (P>.05), training missed due to injury was 60% and 50% greater during the late than during the early competition phase at home and away, respectively. In conclusion, no significant interactions between match location and competition phase were evident during the late competition phase, which suggests that away travel had negligible cumulative effects on the reduction in player wellness in the latter half of the season.
Coyne, Joseph O C; Tran, Tai T; Secomb, Josh L; Lundgren, Lina E; Farley, Oliver R L; Newton, Robert U; Sheppard, Jeremy M
2017-01-01
Coyne, JOC, Tran, TT, Secomb, JL, Lundgren, LE, Farley, ORL, Newton, RU, and Sheppard, JM. Maximal strength training improves surfboard sprint and endurance paddling performance in competitive and recreational surfers. J Strength Cond Res 31(1): 244-253, 2017-Upper-body (UB) strength has very high correlations with faster surfboard paddling speeds. However, there is no research examining the effects of improving UB strength has on surfboard paddling ability. This study aimed to determine the influence that improvements in UB closed-kinetic chain maximal strength have on surfboard paddling in both competitive and recreational surfers. Seventeen competitive and recreational male surfers (29.7 ± 7.7 years, 177.4 ± 7.4 cm, 76.7 ± 9.9 kg) participated in a repeated-measures, parallel control study design. Anthropometry; 5-, 10-, and 15-m sprint; and 400-m endurance surfboard paddling tests along with pull-up and dip 1 repetition maximum strength tests were assessed pre- and postintervention. Subjects in the training group performed 5 weeks of maximal strength training in the pull-up and dip. Differences between the training and control groups were examined postintervention. The training group increased their speed over the 5-, 10-, and 15-m sprint, whereas the control group became slower (d = 0.71, 0.51, and 0.4, respectively). The training group also displayed faster endurance paddling performance compared with the control group (d = 0.72). Short-term exposure to maximal strength training elicits improvements in paddling performance measures. However, the magnitude of performance increases seems to be dependent on initial strength levels with differential responses between strong and weaker athletes. Although a longer maximal strength training period may have produced more significant paddling improvements in stronger subjects, practitioners are unlikely to have any more than 5 weeks in an uninterrupted block with competitive surfing athletes. This study reveals that a "threshold" level of maximal strength that if possessed, short-term maximal strength training may only provide little improvement in paddling performance.
ERIC Educational Resources Information Center
Taylor, Lloyd J., III; Poyner, Ilene
2008-01-01
Purpose: This study aims to investigate the problem of trained employee retention in a highly competitive labor market for a manufacturing facility in the oilfields of West Texas. Design/methodology/approach: This article examines how one manufacturing facility should be able to retain their trained employees by using the logic of Eliyahu M.…
Quiet eye training facilitates competitive putting performance in elite golfers.
Vine, Samuel J; Moore, Lee J; Wilson, Mark R
2011-01-01
The aim of this study was to examine the effectiveness of a brief quiet eye (QE) training intervention aimed at optimizing visuomotor control and putting performance of elite golfers under pressure, and in real competition. Twenty-two elite golfers (mean handicap 2.7) recorded putting statistics over 10 rounds of competitive golf before attending training individually. Having been randomly assigned to either a QE training or Control group, participants were fitted with an Applied Science Laboratories Mobile Eye tracker and performed 20 baseline (pre-test) putts from 10 ft. Training consisted of video feedback of their gaze behavior while they completed 20 putts; however the QE-trained group received additional instructions related to maintaining a longer QE period. Participants then recorded their putting statistics over a further 10 competitive rounds and re-visited the laboratory for retention and pressure tests of their visuomotor control and putting performance. Overall, the results were supportive of the efficacy of the QE training intervention. QE duration predicted 43% of the variance in putting performance, underlying its critical role in the visuomotor control of putting. The QE-trained group maintained their optimal QE under pressure conditions, whereas the Control group experienced reductions in QE when anxious, with subsequent effects on performance. Although their performance was similar in the pre-test, the QE-trained group holed more putts and left the ball closer to the hole on missed putts than their Control group counterparts in the pressure test. Importantly, these advantages transferred to the golf course, where QE-trained golfers made 1.9 fewer putts per round, compared to pre-training, whereas the Control group showed no change in their putting statistics. These results reveal that QE training, incorporated into a pre-shot routine, is an effective intervention to help golfers maintain control when anxious.
48 CFR 6.502 - Duties and responsibilities.
Code of Federal Regulations, 2011 CFR
2011-10-01
... competition in areas such as acquisition training and research; and (vii) Initiatives that ensure task and... ACQUISITION PLANNING COMPETITION REQUIREMENTS Competition Advocates 6.502 Duties and responsibilities. (a) Agency and procuring activity competition advocates are responsible for promoting the acquisition of...
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).
Time to Exhaustion at the VO2max Velocity in Swimming: A Review
Fernandes, Ricardo J.; Vilas-Boas, J. Paulo
2012-01-01
The aim of this study was to present a review on the time to exhaustion at the minimum swimming velocity corresponding to maximal oxygen consumption (TLim-vVO2max). This parameter is critical both for the aerobic power and the lactate tolerance bioenergetical training intensity zones, being fundamental to characterize it, and to point out its main determinants. The few number of studies conducted in this topic observed that swimmers were able to maintain an exercise intensity corresponding to maximal aerobic power during 215 to 260 s (elite swimmers), 230 to 260 s (high level swimmers) and 310 to 325 s (low level swimmers), and no differences between genders were reported. TLim-vVO2max main bioenergetic and functional determinants were swimming economy and VO2 slow component (direct relationship), and vVO2max, velocity at anaerobic threshold and blood lactate production (inverse relationship); when more homogeneous groups of swimmers were analysed, the inverse correlation value between TLim-vVO2max and vVO2max was not so evident. In general, TLim-vVO2max was not related to VO2max. TLim-vVO2max seems also to be influenced by stroking parameters, with a direct relationship to stroke length and stroke index, and an inverse correlation with stroke rate. Assessing TLim-vVO2max, together with the anaerobic threshold and the biomechanical general parameters, will allow a larger spectrum of testing protocols application, helping to build more objective and efficient training programs. PMID:23486651
Teixeira, Angélica; Müller, Liz; dos Santos, Alessandra A; Reckziegel, Patrícia; Emanuelli, Tatiana; Rocha, João Batista T; Bürger, Marilise E
2009-05-01
This study evaluated the preliminary effects of intense physical training (swimming) on oxidative stress in rats with nutritional deficiencies. Rats were fed with a standard diet or a diet deficient in vitamins and minerals for 4 months. The deficient diet contained one-fourth of the recommended vitamin and mineral levels for rats. From the second month, half of the animals were subjected to a swimming exercise in a plastic container with water maintained at 34 +/- 1 degrees C for 1 h/d, five times per week, for 11 wk. The rats were subjected to swimming exercise with loads attached to the dorsal region, which were progressively increased according to their body weight (1% to 7%). Sedentary rats were transported to the experimental room and handled as often in a similar way as the exercise group, except that they were not put in water. In the exercised group, blood lactate levels were significantly lower and the heart weight/body weight ratio was significantly higher than in the sedentary group (P < 0.05). Increased lipid peroxidation was observed in the liver, heart, and skeletal muscle of rats fed with the deficient diet, but it was completely reversed by exercise. Exercise also decreased lipid peroxidation levels in the heart and skeletal muscle of rats fed with the standard diet (P < 0.05). This pilot study leads to the continuity of the studies, because the partial results observed suggest that inadequate nutrition may enhance oxidative stress, and that intense chronic physical training may activate antioxidant defenses, possibly by hormesis.
Training patterns of athletes during pregnancy and postpartum.
Beilock, S L; Feltz, D L; Pivarnik, J M
2001-03-01
The purpose of the present investigation was to examine exercise patterns and psychological variables mediating a return to training and competition after pregnancy. Competitive female athletes who had given birth within the last 10 years completed surveys concerning (a) training patterns before, during, and after childbirth, (b) childbirth complications and training advice, (c) perceptions of success in their postpartum comebacks to training, and (d) self-efficacy, social support, and perceived barriers to training during pregnancy and after childbirth. Results indicated that women decreased both cardiovascular and resistance training during pregnancy. Additionally, training efforts during pregnancy were independent of those during the pre- and postpartum periods. This finding suggests that athletes may be able to alter their training patterns during pregnancy without a significant impact on their postpartum training program.
Althabegoiti, Maria Julia; Covelli, Julieta M; Pérez-Giménez, Julieta; Quelas, Juan Ignacio; Mongiardini, Elías J; López, Maria Florencia; López-García, Silvina L; Lodeiro, Aníbal R
2011-06-01
Bradyrhizobium japonicum has two types of flagella. One has thin filaments consisting of the 33-kDa flagellins FliCI and FliCII (FliCI-II) and the other has thick filaments consisting of the 65-kDa flagellins FliC1, FliC2, FliC3, and FliC4 (FliC1-4). To investigate the roles of each flagellum in competition for nodulation, we obtained mutants deleted in fliCI-II and/or fliC1-4 in the genomic backgrounds of two derivatives from the reference strain USDA 110: the streptomycin-resistant derivative LP 3004 and its more motile derivative LP 3008. All mutations diminished swimming motility. When each mutant was co-inoculated with the parental strain on soybean plants cultivated in vermiculite either at field capacity or flooded, their competitiveness differed according to the flagellin altered. ΔfliCI-II mutants were more competitive, occupying 64-80% of the nodules, while ΔfliC1-4 mutants occupied 45-49% of the nodules. Occupation by the nonmotile double mutant decreased from 55% to 11% as the water content of the vermiculite increased from 85% to 95% field capacity to flooding. These results indicate that the influence of motility on competitiveness depended on the water status of the rooting substrate. © 2011 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.
Effects of resistance training on running economy and cross-country performance.
Barnes, Kyle R; Hopkins, Will G; McGuigan, Michael R; Northuis, Mark E; Kilding, Andrew E
2013-12-01
Heavy-resistance training and plyometric training offer distinct physiological and neuromuscular adaptations that could enhance running economy and, consequently, distance-running performance. To date, no studies have examined the effect of combining the two modes of training on running economy or performance. Fifty collegiate male and female cross-country runners performed a 5-km time trial and a series of laboratory-based tests to determine aerobic, anthropometric, biomechanical, and neuromuscular characteristics. Thereafter, each athlete participated in a season of six to eight collegiate cross-country races for 13 wk. After the first 4 wk, athletes were randomly assigned to either heavy-resistance or plyometric plus heavy-resistance training. Five days after completing their final competition, runners repeated the same set of laboratory tests. We also estimated the effects of the intervention on competition performance throughout the season using athletes of other teams as controls. Heavy-resistance training produced small-moderate improvements in peak speed, running economy, and neuromuscular characteristics relative to plyometric resistance training, whereas changes in biomechanical measures favored plyometric resistance training. Men made less gains than women in most tests. Both treatments had possibly harmful effects on competition times in men (mean = 0.5%; 90% confidence interval = ±1.2%), but there may have been benefit for some individuals. Both treatments were likely beneficial for all women (-1.2%; ±1.3%), but heavy-resistance training was possibly better than plyometric resistance training. The changes in laboratory-based parameters related to distance-running performance were consistent with the changes in competition times for women but only partly for men. Our data indicate that women should include heavy-resistance training in their programs, but men should be cautious about using it in season until more research establishes whether certain men are positive or negative responders.
Competitive employment training for mentally retarded adults: the supported work model.
Krauss, M W; MacEachron, A E
1982-05-01
The supported work model designed to train mentally retarded persons for competitive employment, was initiated as a pilot program in 1979. The placement rate was 50 percent. In order to investigate the predictors of placement, we conducted an empirical analysis using the theory of work adjustment perspective. Results indicated that the participant's work behavior and job skills, ability to meet the requirements of the jobs, and employment reinforcements were predictors of competitive placement.
Education and the Global Marketplace.
ERIC Educational Resources Information Center
Kinzer, Allen O.
Honda of America is part of a global company that strives to be competitive all over the world. In order to maintain and increase its competitiveness, the company focuses intensely on training and retraining its workers and on fostering team spirit. The company maintains extensive training facilities that offer many courses to employees. Employees…
Body Composition and Physiological Responses of Masters Female Swimmers 20 to 70 Years of Age.
ERIC Educational Resources Information Center
Vaccaro, Paul; And Others
1984-01-01
Female masters swimmers ranging in age from 20 to 69 were chosen for a study of their body composition and physiological responses at rest and during exercise. Two training groups were formed that differed on the basis of frequency, duration, and intensity of swimming workouts. Results are discussed. (Author/DF)
Federal Register 2010, 2011, 2012, 2013, 2014
2012-06-07
...). Here, the Navy identifies the distance that a marine mammal is likely to travel during the time... typically travel within a given time-delay period (Table 1). Based on acoustic propagation modeling... Speed and Length of Time-Delay Potential Species group Swim speed Time-delay (min) distance traveled (yd...
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... marine mammal is likely to travel during the time associated with the TDFD's time delay, and that... Navy provided the approximate distance that an animal would typically travel within a given time-delay... Speed and Length of Time-Delay Potential distance Species group Swim speed Time-delay traveled Delphinid...
Federal Register 2010, 2011, 2012, 2013, 2014
2012-03-30
... break, presence of glassy foam, and/or perhaps scattered whitecaps). Applicable mitigation zones are... California based on passive acoustic detection of two distinct echolocation click patterns. No population... 10 1,020 1,220 (2) ZOI and Swim Speed-Time-Buffer Addition Based on acoustic propagation modeling and...
The training intensity distribution among well-trained and elite endurance athletes
Stöggl, Thomas L.; Sperlich, Billy
2015-01-01
Researchers have retrospectively analyzed the training intensity distribution (TID) of nationally and internationally competitive athletes in different endurance disciplines to determine the optimal volume and intensity for maximal adaptation. The majority of studies present a “pyramidal” TID with a high proportion of high volume, low intensity training (HVLIT). Some world-class athletes appear to adopt a so-called “polarized” TID (i.e., significant % of HVLIT and high-intensity training) during certain phases of the season. However, emerging prospective randomized controlled studies have demonstrated superior responses of variables related to endurance when applying a polarized TID in well-trained and recreational individuals when compared with a TID that emphasizes HVLIT or threshold training. The aims of the present review are to: (1) summarize the main responses of retrospective and prospective studies exploring TID; (2) provide a systematic overview on TIDs during preparation, pre-competition, and competition phases in different endurance disciplines and performance levels; (3) address whether one TID has demonstrated greater efficacy than another; and (4) highlight research gaps in an effort to direct future scientific studies. PMID:26578968
The training intensity distribution among well-trained and elite endurance athletes.
Stöggl, Thomas L; Sperlich, Billy
2015-01-01
Researchers have retrospectively analyzed the training intensity distribution (TID) of nationally and internationally competitive athletes in different endurance disciplines to determine the optimal volume and intensity for maximal adaptation. The majority of studies present a "pyramidal" TID with a high proportion of high volume, low intensity training (HVLIT). Some world-class athletes appear to adopt a so-called "polarized" TID (i.e., significant % of HVLIT and high-intensity training) during certain phases of the season. However, emerging prospective randomized controlled studies have demonstrated superior responses of variables related to endurance when applying a polarized TID in well-trained and recreational individuals when compared with a TID that emphasizes HVLIT or threshold training. The aims of the present review are to: (1) summarize the main responses of retrospective and prospective studies exploring TID; (2) provide a systematic overview on TIDs during preparation, pre-competition, and competition phases in different endurance disciplines and performance levels; (3) address whether one TID has demonstrated greater efficacy than another; and (4) highlight research gaps in an effort to direct future scientific studies.
NASA Astrophysics Data System (ADS)
Xu, Yishen; Wu, Di; Chen, Daqing; Gu, Jihua; Gao, Lei
2017-08-01
According to the inherent requirements of education for talents' knowledge, quality and comprehensive ability and the major training goals of optoelectronics information science and engineering, in order to enhance the undergraduates' comprehensive practical ability and consciousness of innovation, we carried out the reforms of teaching method and teaching mode, which took the training programs of innovation and entrepreneurship for undergraduates, extracurricular academic research fund, "Chun-Tsung Scholar" program or research projects of their tutors as the guidance, and took the all levels of relevant discipline competitions as the promotion. And the training mainline of engineering innovation talents as "undergraduate's tutorial system ->innovative training program or tutor's research project ->academic competition ->graduation projects (thesis)" was constructed stage by stage by combining the undergraduates' graduation projects and their participated academic competition into one for improving the quality of the graduation projects (thesis). The practical results of the last several years illuminate that the proposed training model can effectively stimulate the students' awareness of autonomous learning, enhance their comprehensive ability of analyzing and solving problems and improve their ability of engineering practice and innovation as well as their teamwork spirit.
Yang, Yun
2007-02-01
In order to investigate the feasibility of serum creatine kinase (CK) and blood urea nitrogen (BUN) in monitoring pre-competition training of badminton athletes, the pre-competition training load of 20 badminton athletes was studied, and serum CK and BUN were determined before, immediate and next morning after training. The results showed that after intensive training for one week, serum CK levels were significantly increased by 57.53 mmol/L (P<0.05). After regulation of the training intensity, average serum CK levels were increased by 21.79 mmol/L (P<0.05). BUN contents were increased by 0.83 mmol/L on average with the difference being not significant (P>0.05). After intermittent training, there was significant difference in the average increased levels of serum CK in athletes (P<0.05). There was significant difference before and after regulation of training (P<0.05). The increased levels of BUN were 0.78 mmol/L without significant difference (P>0.05). It was concluded that serum CK was one of the biochemical indicators monitoring the training load sensitivity of badminton athletes, but BUN was of little value in monitoring the training load. Both serum CK and BUN recovered slowly after one-week intensive training and intermittent training, suggesting the metabolic mechanism of human body in training needs further study.
DiNovo, Karyn. M.; Connolly, Tiffanny M.
2010-01-01
The mammalian diving response, consisting of apnea, bradycardia, and increased total peripheral resistance, can be modified by conscious awareness, fear, and anticipation. We wondered whether swim and dive training in rats would 1) affect the magnitude of the cardiovascular responses during voluntary and forced diving, and 2) whether this training would reduce or eliminate any stress due to diving. Results indicate Sprague-Dawley rats have a substantial diving response. Immediately upon submersion, heart rate (HR) decreased by 78%, from 453 ± 12 to 101 ± 8 beats per minute (bpm), and mean arterial pressure (MAP) decreased 25%, from 143 ± 1 to 107 ± 5 mmHg. Approximately 4.5 s after submergence, MAP had increased to a maximum 174 ± 3 mmHg. Blood corticosterone levels indicate trained rats find diving no more stressful than being held by a human, while untrained rats find swimming and diving very stressful. Forced diving is stressful to both trained and untrained rats. The magnitude of bradycardia was similar during both voluntary and forced diving, while the increase in MAP was greater during forced diving. The diving response of laboratory rats, therefore, appears to be dissimilar from that of other animals, as most birds and mammals show intensification of diving bradycardia during forced diving compared with voluntary diving. Rats may exhibit an accentuated antagonism between the parasympathetic and sympathetic branches of the autonomic nervous system, such that in the autonomic control of HR, parasympathetic activity overpowers sympathetic activity. Additionally, laboratory rats may lack the ability to modify the degree of parasympathetic outflow to the heart during an intense cardiorespiratory response (i.e., the diving response). PMID:19923359
Yang, Kai-Chien; Tseng, Yi-Tang; Nerbonne, Jeanne M.
2012-01-01
In contrast with pathological hypertrophy, exercise-induced physiological hypertrophy is not associated with electrical abnormalities or increased arrhythmia risk. Recent studies have shown that increased cardiac-specific expression of phosphoinositide-3-kinase-α (PI3Kα), the key mediator of physiological hypertrophy, results in transcriptional upregulation of ion channel subunits in parallel with the increase in myocyte size (cellular hypertrophy) and the maintenance of myocardial excitability. The experiments here were undertaken to test the hypothesis that Akt1, which underlies PI3Kα-induced cellular hypertrophy, mediates the effects of augmented PI3Kα signaling on the transcriptional regulation of cardiac ion channels. In contrast to wild-type animals, chronic exercise (swim) training of mice (Akt1−/−) lacking Akt1 did not result in ventricular myocyte hypertrophy. Ventricular K+ current amplitudes and the expression of K+ channel subunits, however, were increased markedly in Akt1−/− animals with exercise training. Expression of the transcripts encoding inward (Na+ and Ca2+) channel subunits were also increased in Akt1−/− ventricles following swim training. Additional experiments in a transgenic mouse model of inducible cardiac-specific expression of constitutively active PI3Kα (icaPI3Kα) revealed that short-term activation of PI3Kα signaling in the myocardium also led to the transcriptional upregulation of ion channel subunits. Inhibition of cardiac Akt activation with triciribine in this (inducible caPI3Kα expression) model did not prevent the upregulation of myocardial ion channel subunits. These combined observations demonstrate that chronic exercise training and enhanced PI3Kα expression/activity result in transcriptional upregulation of myocardial ion channel subunits independent of cellular hypertrophy and Akt signaling. PMID:22824041
Aquino, Antonio E.; Sene-Fiorese, Marcela; Paolillo, Fernanda R.; Duarte, Fernanda O.; Oishi, Jorge C.; Pena, Airton A.; Duarte, Ana C. G. O.; Hamblin, Michael R.; Bagnato, Vanderlei S.; Parizotto, Nivaldo A.
2012-01-01
Obesity and associated dyslipidemia is the fastest growing health problem throughout the world. The combination of exercise and low-level laser therapy (LLLT) could be a new approach to the treatment of obesity and associated disease. In this work, the effects of LLLT associated with exercises on the lipid metabolism in regular and high-fat diet rats were verified. We used 64 rats divided in eight groups with eight rats each, designed: SC, sedentary chow diet; SCL, sedentary chow diet laser, TC, trained chow diet; TCL, trained chow diet laser; SH, sedentary high-fat diet; SHL, sedentary high-fat diet laser; TH, trained high-fat diet; and THL, trained high-fat diet laser. The exercise used was swimming during 8 weeks/90 min daily and LLLT (GA-Al-As, 830 nm) dose of 4.7 J/point and total energy 9.4 J per animal, applied to both gastrocnemius muscles after exercise. We analyzed biochemical parameters, percentage of fat, hepatic and muscular glycogen and relative mass of tissue, and weight percentage gain. The statistical test used was ANOVA, with post hoc Tukey–Kramer for multiple analysis between groups, and the significant level was p<0.001, p<0.01, and p<0.05. LLLT decreased the total cholesterol (p<0.05), triglycerides (p<0.01), low-density lipoprotein cholesterol (p<0.05), and relative mass of fat tissue (p<0.05), suggesting increased metabolic activity and altered lipid pathways. The combination of exercise and LLLT increased the benefits of exercise alone. However, LLLT without exercise tended to increase body weight and fat content. LLLT may be a valuable addition to a regimen of diet and exercise for weight reduction and dyslipidemic control. PMID:23151893
A novel method to guide classification of para swimmers with limb deficiency.
Hogarth, Luke; Payton, Carl; Van de Vliet, Peter; Connick, Mark; Burkett, Brendan
2018-05-30
The International Paralympic Committee has directed International Federations that govern Para sports to develop evidence-based classification systems. This study defined the impact of limb deficiency impairment on 100 m freestyle performance to guide an evidence-based classification system in Para Swimming, which will be implemented following the 2020 Tokyo Paralympic games. Impairment data and competitive race performances of 90 international swimmers with limb deficiency were collected. Ensemble partial least squares regression established the relationship between relative limb length measures and competitive 100 m freestyle performance. The model explained 80% of the variance in 100 m freestyle performance, and found hand length and forearm length to be the most important predictors of performance. Based on the results of this model, Para swimmers were clustered into four-, five-, six- and seven-class structures using nonparametric kernel density estimations. The validity of these classification structures, and effectiveness against the current classification system, were examined by establishing within-class variations in 100 m freestyle performance and differences between adjacent classes. The derived classification structures were found to be more effective than current classification based on these criteria. This study provides a novel method that can be used to improve the objectivity and transparency of decision-making in Para sport classification. Expert consensus from experienced coaches, Para swimmers, classifiers and sport science and medicine personnel will benefit the translation of these findings into a revised classification system that is accepted by the Para swimming community. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
The Research on the Impact of Green Beans Sports Drinks on Relieving Fatigue in Sports Training.
Qi, Li; Ying, Liu
2015-01-01
For researching the function of relieving fatigue of green beans sports drinks, this paper selected 60 mice as subjects. They were randomly divided into four groups (low dose group, middle dose group, high dose group and physiological saline group). Each time they were respectively feed 10g 20g/L, 40g/L, 80 g/L green beans sports drinks and 15ml/(kg.d) physiological saline. The experiment lasted for a month. We recorded weight of mice, swimming time and blood urea nitrogen indicators. The results show that green beans sports drinks can significantly prolong swimming time of mice (p <0.05). For serum urea the results show no effect. So green beans sports drinks have a certain function of relieving physical fatigue.
Rubio, Julio; Caldas, Maria; Dávila, Sonia; Gasco, Manuel; Gonzales, Gustavo F
2006-01-01
Background Lepidium meyenii Walp. (Brassicaceae), known as Maca, is a Peruvian hypocotyl growing exclusively between 4000 and 4500 m altitude in the central Peruvian Andes, particularly in Junin plateau and is used traditionally to enhance fertility. Maca is a cultivated plant and different cultivars are described according to the color of the hypocotyls. Methods The study aimed to elucidate the effect of Yellow, Red and Black Maca on cognitive function and depression in ovariectomized (OVX) mice. In all experiments OVX mice were treated during 21 days and divided in four groups: control group, Yellow Maca, Red Maca and Black Maca. Latent learning was assessed using the water finding task and the antidepressant activity of the three varieties of Maca was evaluated using the forced swimming test. Animals were sacrificed at the end of each treatment and the uterus were excised and weighed. Results Black Maca was the variety that showed the best response in the water finding task, particularly in the trained mice. The three varieties were effective to reduce finding latency in non trained and trained mice (P < 0.05). In the force swimming test, all varieties assessed reduced the time of immobility and increased uterine weight in OVX mice. Conclusion Black Maca appeared to have more beneficial effects on latent learning in OVX mice; meanwhile, all varieties of Maca showed antidepressant activity. PMID:16796734
Rubio, Julio; Caldas, Maria; Dávila, Sonia; Gasco, Manuel; Gonzales, Gustavo F
2006-06-23
Lepidium meyenii Walp. (Brassicaceae), known as Maca, is a Peruvian hypocotyl growing exclusively between 4000 and 4500 m altitude in the central Peruvian Andes, particularly in Junin plateau and is used traditionally to enhance fertility. Maca is a cultivated plant and different cultivars are described according to the color of the hypocotyls. The study aimed to elucidate the effect of Yellow, Red and Black Maca on cognitive function and depression in ovariectomized (OVX) mice. In all experiments OVX mice were treated during 21 days and divided in four groups: control group, Yellow Maca, Red Maca and Black Maca. Latent learning was assessed using the water finding task and the antidepressant activity of the three varieties of Maca was evaluated using the forced swimming test. Animals were sacrificed at the end of each treatment and the uterus were excised and weighed. Black Maca was the variety that showed the best response in the water finding task, particularly in the trained mice. The three varieties were effective to reduce finding latency in non trained and trained mice (P < 0.05). In the force swimming test, all varieties assessed reduced the time of immobility and increased uterine weight in OVX mice. Black Maca appeared to have more beneficial effects on latent learning in OVX mice; meanwhile, all varieties of Maca showed antidepressant activity.
Campus, P; Colelli, V; Orsini, C; Sarra, D; Cabib, S
2015-02-01
The forced swimming test (FST) remains one of the most used tools for screening antidepressants in rodent models. Nonetheless, the nature of immobility, its main behavioral measure, is still a matter of debate. The present study took advantage of our recent finding that mice of the inbred DBA/2J strain require a functioning left dorsolateral striatum (DLS) to consolidate long-term memory of FST to test whether immobility is the outcome of stress-related learning. Infusion of the GABA-A agonist muscimol in the left DLS immediately after a single experience of FST prevented and infusion in the left or the right amygdala impaired recall of the acquired levels of immobility in a probe test performed 24h later. Post-training left DLS infusion of muscimol, at a dose capable of preventing retention of FST-induced immobility, did not influence 24h retention of inhibitory avoidance training or of the escape response acquired in a water T-maze. However, this same treatment prevented 24h retention of the extinction training of the consolidated escape response. These results indicate that a left DLS-centered memory system selectively mediates memory consolidation of FST and of escape extinction and support the hypothesis that immobility is the result of extinction-like inhibitory learning involving all available escape responses due to the inescapable/unavoidable nature of FST experience. Copyright © 2014 Elsevier B.V. All rights reserved.
Metabolic predictors of middle-distance swimming performance.
Ribeiro, J P; Cadavid, E; Baena, J; Monsalvete, E; Barna, A; De Rose, E H
1990-01-01
To evaluate the capacity of different metabolic indices to predict performance in middle distance swimming, 15 competitive swimmers performed a submaximal and a maximal 400 metres freestyle swimming event. Expired gases were collected in Douglas bags immediately after the events for the determination of VO2 max. Arterialized blood samples were collected for the determination of maximal blood lactate concentration and the velocity corresponding to blood lactate concentration of 4 mM. The results demonstrated (means +/- SD): maximal velocity of 1.44 +/- 0.05 m.s-1; velocity at 85 percent of VO2 max of 1.36 +/- 0.04 m.s-1; velocity at 4 mM of 1.32 +/- 0.04 m.s-1; VO2 max of 3.47 +/- 0.5 l.min-1; maximal blood lactate concentration of 11.8 +/- 2.5 mM. Multiple regression analysis relating metabolic indices and maximal velocity demonstrated that only velocity at 85 percent of VO2 max (r2 = 0.81) and velocity at 4 mM (r2 = 0.79) were significant predictors. Thus, 79 percent of the variance in the performance of 400 m freestyle can be accounted for the velocity at 85 percent of VO2 max or the velocity at 4 mM. The success in this event seems to depend on the swimmer's capacity to achieve higher velocities with lower blood lactate levels and/or utilizing a lower percentage of their VO2 max. PMID:2078807
Tønnessen, Espen; Sylta, Øystein; Haugen, Thomas A.; Hem, Erlend; Svendsen, Ida S.; Seiler, Stephen
2014-01-01
Purpose To describe training variations across the annual cycle in Olympic and World Champion endurance athletes, and determine whether these athletes used tapering strategies in line with recommendations in the literature. Methods Eleven elite XC skiers and biathletes (4 male; 28±1 yr, 85±5 mL. min−1. kg−1 , 7 female, 25±4 yr, 73±3 mL. min−1. kg−1 ) reported one year of day-to-day training leading up to the most successful competition of their career. Training data were divided into periodization and peaking phases and distributed into training forms, intensity zones and endurance activity forms. Results Athletes trained ∼800 h/500 sessions.year−1, including ∼500 h. year−1 of sport-specific training. Ninety-four percent of all training was executed as aerobic endurance training. Of this, ∼90% was low intensity training (LIT, below the first lactate threshold) and 10% high intensity training (HIT, above the first lactate threshold) by time. Categorically, 23% of training sessions were characterized as HIT with primary portions executed at or above the first lactate turn point. Training volume and specificity distribution conformed to a traditional periodization model, but absolute volume of HIT remained stable across phases. However, HIT training patterns tended to become more polarized in the competition phase. Training volume, frequency and intensity remained unchanged from pre-peaking to peaking period, but there was a 32±15% (P<.01) volume reduction from the preparation period to peaking phase. Conclusions The annual training data for these Olympic and World champion XC skiers and biathletes conforms to previously reported training patterns of elite endurance athletes. During the competition phase, training became more sport-specific, with 92% performed as XC skiing. However, they did not follow suggested tapering practice derived from short-term experimental studies. Only three out of 11 athletes took a rest day during the final 5 days prior to their most successful competition. PMID:25019608
Tønnessen, Espen; Sylta, Øystein; Haugen, Thomas A; Hem, Erlend; Svendsen, Ida S; Seiler, Stephen
2014-01-01
To describe training variations across the annual cycle in Olympic and World Champion endurance athletes, and determine whether these athletes used tapering strategies in line with recommendations in the literature. Eleven elite XC skiers and biathletes (4 male; 28±1 yr, 85±5 mL x min(-1) x kg(-1) VO2max, 7 female, 25±4 yr, 73±3 mL x min(-1) x kg(-1) VO2max) reported one year of day-to-day training leading up to the most successful competition of their career. Training data were divided into periodization and peaking phases and distributed into training forms, intensity zones and endurance activity forms. Athletes trained ∼800 h/500 sessions x year(-1), including ∼500 h x year(-1) of sport-specific training. Ninety-four percent of all training was executed as aerobic endurance training. Of this, ∼90% was low intensity training (LIT, below the first lactate threshold) and 10% high intensity training (HIT, above the first lactate threshold) by time. Categorically, 23% of training sessions were characterized as HIT with primary portions executed at or above the first lactate turn point. Training volume and specificity distribution conformed to a traditional periodization model, but absolute volume of HIT remained stable across phases. However, HIT training patterns tended to become more polarized in the competition phase. Training volume, frequency and intensity remained unchanged from pre-peaking to peaking period, but there was a 32±15% (P<.01) volume reduction from the preparation period to peaking phase. The annual training data for these Olympic and World champion XC skiers and biathletes conforms to previously reported training patterns of elite endurance athletes. During the competition phase, training became more sport-specific, with 92% performed as XC skiing. However, they did not follow suggested tapering practice derived from short-term experimental studies. Only three out of 11 athletes took a rest day during the final 5 days prior to their most successful competition.
Breaststroke swimmer's knee. A biomechanical and arthroscopic study.
Keskinen, K; Eriksson, E; Komi, P
1980-01-01
The cause of the breaststroke swimmer's knee with medial pain of the knee joint has not been clearly identified. Breaststroke swimmers with knee pain were, therefore, examined arthroscopically. None showed any other disorders of their knees than medial synovitis in seven of nine swimmers. Since structural abnormalities could be ruled out, biomechanical analyses utilizing cinematographic techniques were used to study patients swimming in a special flume with the speed set at 90% of their best competitive performance. The results indicate that the extension and flexion and also in some cases the hip abduction and adduction movements of the whip kick were performed with high peak angular velocities. No significant differences in swimming technique among the six patients studied and three controls could be observed. It is concluded that a combination of high angular velocities at the hip and knee and external rotation of the tibia relative to the femur repeated in excessive amounts might be the primary cause for the medial synovitis documented in these patients. The breaststroker's knee thus seems to be an overuse syndrome.
75 FR 5090 - Notice of Meeting
Federal Register 2010, 2011, 2012, 2013, 2014
2010-02-01
...). Grant applications for the ARRA: Limited Competition ``AHRQ Institutional Training Grants for CE'' (K12... disclosure under the above-cited statutes. SEP Meeting on: ARRA: Limited Competition ``AHRQ Institutional Training Grants for CE'' (K12). Date: March 3, 2010 (Open on March 3 from 8:00 a.m. to 8:15 a.m. and closed...
Development and Initial Psychometric Evaluation of the Sport Interference Checklist
ERIC Educational Resources Information Center
Donohue, Brad; Silver, N. Clayton; Dickens, Yani; Covassin, Tracey; Lancer, Kevin
2007-01-01
The Sport Interference Checklist (SIC) was developed in 141 athletes to assist in the concurrent assessment of cognitive and behavioral problems experienced by athletes in both training (Problems in Sports Training Scale, PSTS) and competition (Problems in Sports Competition Scale, PSCS). An additional scale (Desire for Sport Psychology Scale,…
ERIC Educational Resources Information Center
Schupp, Karen
2010-01-01
This article examines the methods the author uses to help first-year dance majors from competitive training backgrounds expand their understanding of dance and learn to create a strong foundation for collegiate success. By acknowledging differences in dance backgrounds, carefully emphasizing the theory behind postmodern contemporary dance…
Negative plant-soil feedbacks increase with plant abundance, and are unchanged by competition.
Maron, John L; Laney Smith, Alyssa; Ortega, Yvette K; Pearson, Dean E; Callaway, Ragan M
2016-08-01
Plant-soil feedbacks and interspecific competition are ubiquitous interactions that strongly influence the performance of plants. Yet few studies have examined whether the strength of these interactions corresponds with the abundance of plant species in the field, or whether feedbacks and competition interact in ways that either ameliorate or exacerbate their effects in isolation. We sampled soil from two intermountain grassland communities where we also measured the relative abundance of plant species. In greenhouse experiments, we quantified the direction and magnitude of plant-soil feedbacks for 10 target species that spanned a range of abundances in the field. In soil from both sites, plant-soil feedbacks were mostly negative, with more abundant species suffering greater negative feedbacks than rare species. In contrast, the average response to competition for each species was unrelated with its abundance in the field. We also determined how competitive response varied among our target species when plants competed in live vs. sterile soil. Interspecific competition reduced plant size, but the strength of this negative effect was unchanged by plant-soil feedbacks. Finally, when plants competed interspecifically, we asked how conspecific-trained, heterospecific-trained, and sterile soil influenced the competitive responses of our target species and how this varied depending on whether target species were abundant or rare in the field. Here, we found that both abundant and rare species were not as harmed by competition when they grew in heterospecific-trained soil compared to when they grew in conspecific-cultured soil. Abundant species were also not as harmed by competition when growing in sterile vs. conspecific-trained soil, but this was not the case for rare species. Our results suggest that abundant plants accrue species-specific soil pathogens to a greater extent than rare species. Thus, negative feedbacks may be critical for preventing abundant species from becoming even more abundant than rare species. © 2016 by the Ecological Society of America.
Mujika, Iñigo; Halson, Shona; Burke, Louise M; Balagué, Gloria; Farrow, Damian
2018-05-01
Sports periodization has traditionally focused on the exercise aspect of athletic preparation, while neglecting the integration of other elements that can impact an athlete's readiness for peak competition performances. Integrated periodization allows the coordinated inclusion of multiple training components best suited for a given training phase into an athlete's program. The aim of this article is to review the available evidence underpinning integrated periodization, focusing on exercise training, recovery, nutrition, psychological skills, and skill acquisition as key factors by which athletic preparation can be periodized. The periodization of heat and altitude adaptation, body composition, and physical therapy is also considered. Despite recent criticism, various methods of exercise training periodization can contribute to performance enhancement in a variety of elite individual and team sports, such as soccer. In the latter, both physical and strategic periodization are useful tools for managing the heavy travel schedule, fatigue, and injuries that occur throughout a competitive season. Recovery interventions should be periodized (ie, withheld or emphasized) to influence acute and chronic training adaptation and performance. Nutrient intake and timing in relation to exercise and as part of the periodization of an athlete's training and competition calendar can also promote physiological adaptations and performance capacity. Psychological skills are a central component of athletic performance, and their periodization should cater to each athlete's individual needs and the needs of the team. Skill acquisition can also be integrated into an athlete's periodized training program to make a significant contribution to competition performance.
Hellard, Philippe; Avalos, Marta; Millet, Gregoire; Lacoste, Lucien; Barale, Frederic; Chatard, Jean-Claude
2005-02-01
The aim of this study was to model the residual effects of training on the swimming performance and to compare a model that includes threshold saturation (MM) with the Banister model (BM). Seven Olympic swimmers were studied over a period of 4 +/- 2 years. For 3 training loads (low-intensity w(LIT), high-intensity w(HIT), and strength training w(ST)), 3 residual training effects were determined: short-term (STE) during the taper phase (i.e., 3 weeks before the performance [weeks 0, 1, and 2]), intermediate-term (ITE) during the intensity phase (weeks 3, 4, and 5), and long-term (LTE) during the volume phase (weeks 6, 7, and 8). ITE and LTE were positive for w(HIT) and w(LIT), respectively (p < 0.05). Low-intensity training load during taper was related to performances by a parabolic relationship (p < 0.05). Different quality measures indicated that MM compares favorably with BM. Identifying individual training thresholds may help individualize the distribution of training loads.
Tsoufi, Anastasia; Maraki, Maria I; Dimitrakopoulos, Leonidas; Famisis, Konstantinos; Grammatikopoulou, Maria G
2017-10-01
Literature suggests that dietary intake of elite athletes may differ between training and competition days. In addition, despite the importance of nutrition in sports and the popularity of basketball, studies on the diet of basketball players are scarce. Therefore, the aim of the present study was to assess dietary intake and diet quality in training and competition days in a team of elite basketball players receiving daily professional nutritional counseling. One elite basketball team (N.=15) participating in EuroLeague volunteered for the study. The team employed a certified dietitian, responsible for providing individualized nutritional evaluation and counseling, dietary planning and supervision of the diet of all the players. Dietary intake was assessed using 24-hour recalls and the Healthy Eating Index (HEI) was then calculated. All players exhibited adequate (i.e., >80) HEI score (raw and adjusted for energy intake [EI]), on both training and competition days. Although daily energy, carbohydrate and protein intakes were greater during training compared to competition days (26.0 [21.7, 26.4] vs. 19.5 [19.3, 22.1] MJ, 7.6±1.5 vs. 6.8±0.9 g/kg of body weight [BW] and 2.6±0.6 vs. 2.2±0.2 g/kg BW, respectively; all P<0.05), HEI score (raw and adjusted for EI) was lower in training compared to competition days (92.9 [82.1, 93.2] vs. 94.0 [94.0, 94.0] and 89.7 [88.4, 89.7] vs. 92.7 [91.7, 92.8], respectively; all P≤0.001) due to lower total grains, whole grains and total vegetables consumption and greater saturated fats consumption (P<0.05). Elite basketball players receiving daily nutritional counseling by certified sports dietitians exhibit adequate diet quality, with the highest possible observed during competition days.
Quiet Eye Training Facilitates Competitive Putting Performance in Elite Golfers
Vine, Samuel J.; Moore, Lee J.; Wilson, Mark R.
2011-01-01
The aim of this study was to examine the effectiveness of a brief quiet eye (QE) training intervention aimed at optimizing visuomotor control and putting performance of elite golfers under pressure, and in real competition. Twenty-two elite golfers (mean handicap 2.7) recorded putting statistics over 10 rounds of competitive golf before attending training individually. Having been randomly assigned to either a QE training or Control group, participants were fitted with an Applied Science Laboratories Mobile Eye tracker and performed 20 baseline (pre-test) putts from 10 ft. Training consisted of video feedback of their gaze behavior while they completed 20 putts; however the QE-trained group received additional instructions related to maintaining a longer QE period. Participants then recorded their putting statistics over a further 10 competitive rounds and re-visited the laboratory for retention and pressure tests of their visuomotor control and putting performance. Overall, the results were supportive of the efficacy of the QE training intervention. QE duration predicted 43% of the variance in putting performance, underlying its critical role in the visuomotor control of putting. The QE-trained group maintained their optimal QE under pressure conditions, whereas the Control group experienced reductions in QE when anxious, with subsequent effects on performance. Although their performance was similar in the pre-test, the QE-trained group holed more putts and left the ball closer to the hole on missed putts than their Control group counterparts in the pressure test. Importantly, these advantages transferred to the golf course, where QE-trained golfers made 1.9 fewer putts per round, compared to pre-training, whereas the Control group showed no change in their putting statistics. These results reveal that QE training, incorporated into a pre-shot routine, is an effective intervention to help golfers maintain control when anxious. PMID:21713182
The Elementary Triathlon: Change the "I" to "Y" and Add "ES"
ERIC Educational Resources Information Center
Docheff, Dennis
2008-01-01
The triathlon has become very popular in the fitness world. Athletes train for months and even years to get their bodies in top shape to attempt the three-part triathlon race--swim, bike, and distance run. While this activity continues to grow in popularity across the country, the purpose of this article is to create an appropriate triathlon for…
Swinton, Paul A; Lloyd, Ray; Agouris, Ioannis; Stewart, Arthur
2009-03-01
The primary objective of this study was to investigate current powerlifting training methods in light of anecdotal evidence purporting increased similarity with the explosive training practices of weightlifters. The study also assessed the prevalence of contemporary training practices frequently recommended for powerlifters in the popular literature. A 20-item survey was distributed to 32 elite British powerlifters at an International competition. The subject group included multiple national, international, and commonwealth champions and record holders. Based on 2007 competition results, the average Wilks score of the group was 450.26 +/- 34.7. The response rate for the surveys was 88% (28 of 32). The survey was sectioned into 6 areas of inquiry: a) repetition speed, b) explosive training load, c) resistance materials used, d) adjunct power training methods, e) exercise selection, and f) training organization. The results demonstrate that the majority of powerlifters train with the intention to explosively lift maximal and submaximal loads (79 and 82%, respectively). Results revealed that 39% of the lifters regularly used elastic bands and that 57% incorporated chains in their training. Evidence for convergence of training practices between powerlifters and weightlifters was found when 69% of the subjects reported using the Olympic lifts or their derivatives as part of their powerlifting training. Collectively, the results demonstrate that previous notions of how powerlifters train are outdated. Contemporary powerlifters incorporate a variety of training practices that are focused on developing both explosive and maximal strength.