INTRODUÇÃO. A força muscular e o equilíbrio do tronco são os aspectos mais importantes para a determinação da classificação funcional de atletas de basquetebol em cadeira de rodas. O objetivo deste estudo foi analisar e correlacionar a força muscular e os limites de estabilidade do tronco de acordo com a classificação funcional para atletas de basquetebol em cadeira de rodas. MÉTODOS. Quarenta e dois atletas, com classificação funcional homologada pela federação paulista da modalidade, distribuídos nas quatro classes do Basquetebol em Cadeira de Rodas (Classe 1 n= 11; Classe 2 n=11; Classe 3 n= 9; Classe 4 n=11) com média de idade de 28,3±7.4 (16-46) anos, do sexo masculino tiveram a força muscular e equilíbrio de tronco avaliados. A força do tronco foi avaliada nos músculos extensores e flexores utilizando o dinamômetro isocinético Biodex® de forma isométrica com 15 º de amplitude. Os atletas realizaram uma série de 10 repetições com 15 segundos de descanso entre cada repetição. O equilíbrio do tronco foi avaliado no equipamento Balance Master® e o teste utilizado foi o de Limites de Estabilidade (LOS) de forma adaptada. Os atletas, sentados em um banco, realizaram movimentos voluntários do tronco em oito direções no plano frontal e lateral. Os movimentos foram feitos no sentido horário, ao redor de um perímetro, visualizado pelo paciente em um monitor e que representa o limite de 100% de deslocamento dado pelo equipamento. RESULTADOS. Considerando a distribuição dos atletas nas classes, houve diferença significativa na comparação dos índices de força muscular e equilíbrio entre as classes 1x3; 1x4 e 2x4. Houve correlação negativa (moderada) entre a força muscular do tronco em flexão e o DM (r=-.68, p=.02. Houve correlação positiva (forte) na classe 3 da força muscular do tronco em extensão e o DM (r=.92 p=0,001). CONCLUSÃO. A força muscular isométrica de flexão e extensão do tronco e os índices de equilíbrios de VD e DM nas direções anterior, posterior aumentam progressivamente com as classes e apresentam maiores diferenças na comparação entre as classes 1 e 3 e 1 e 4 e 2 e 4. Não houve correlação entre a força muscular isométrica dos flexores e extensores do tronco e os limites de estabilidade de acordo com a classificação funcional do BCR / BACKGROUND. Trunk muscle strength and balance are very important in defining the class of wheelchair basketball (WCB) athletes. This study aims to correlate and analyze trunk muscle strength and balance among high-performance Brazilian WCB athletes with their functional classification. METHODS. Forty-two male athletes of mean age 28.3±7.4 years (16-46) were divided into four groups based on WCB classes as follow: class 1 n=11; class 2 n=11; class 3 n=9; and class 4 n=11. The athletes performed a set of 10 repetitions of trunk flexion and extension with 15 seconds of rest between each repetition using the BiodexR isokinetic dynamometer in isometric form, with amplitude 15° to evaluate trunk muscle strength. In order to evaluate trunk balance, using the Balance Master® equipment and the Limits of Stability test (LOS), the athletes made voluntary trunk movements in eight directions (clockwise) in the frontal and lateral planes while seated on a bench. During the test, the athletes could view the movements on a monitor that represented the 100% displacement limit given by the equipment. RESULTS. There were significant differences in comparisons of trunk muscle strength and LOS in the classes 1vs.3, 1vs.4 and 2 vs.4. There was moderate negative correlation between trunk muscle strength in flexion and maximum excursion (r=-0.68; p=0.02). There was a strong positive correlation in class 3 between trunk muscle strength in extension and maximum excursion (r=0.92;p= 0.001). CONCLUSION. There was no correlation of isometric trunk muscle strength in flexion and extension and LOS indices, according to the functional classification of the WCB athletes

Preliminary normative standards are a tool clinical exercise specialists and health fitness instructors can use when interpreting muscular strength testing results. However, a challenge for professionals is evaluating an individual's one-repetition maximum (IRM) and relating that to others of the same age and gender, because there are no preliminary normative standards for 1RMs available when testing via free-weights and machines.This study conducted at Ball State University, Adult Physical Fitness Laboratory, examined results of muscular strength testing in order to obtain the normative muscular strength of adults. The purpose was to develop preliminary normative standards for strength of adults and to compare the 1RM weight an individual lifts between free-weights, Paramount, and Cybex machines. Seventy-nine healthy men and women between 18 and 79 years of age participated in the study. Subjects were tested on free weights, Paramount, and Cybex machines.Test results revealed preliminary normative standards for 1RM on free weights. Individuals were categorized in three age groups for the free-weight bench press and the Cybex (free-weight) Leg Press. The 18-23 year olds obtained a IRM mean (± Standard Deviation (SD)) of 200.6 + 32.8 lbs and 83.6 ± 18.5 lbs for men and women, respectively, for the free-weight bench press. The 43-59 year olds obtained a 1RM mean of 149.2 ± 41.8 lbs and 71.3 ± 8.6 lbs and the 60-79 year olds had a 1RM mean of 119.5 + 30.0 Ibs and 61.6 ± 15.6 lbs for men and women, respectively, for the free-weight bench press. The 18-23 year olds obtained a 1RM Cybex (free-weight) leg press mean of 484.9 + 58.0 lbs and 234.3 ± 67.5 lbs for men and women, respectively. The 43-59 year olds were able to obtain 1RM means of 444.4 + 84.9 lbs and 254.5 ± 51.7 lbs and the older subjects (60-79 years old) were able to obtain 1RM mean of 390.7 ± 98.6 lbs and 230.3 ± 76.6 lbs for men and women, respectively. Results were also documented in relative values by the amount of weight pushed divided by body weight for better comparison of individuals. Subjects generally lifted more weight on the Cybex (free-weight) leg press compared to the Cybex (machine) leg press. All subjects (N=79) had a mean and standard deviation of 294.9 + 87.7 lbs for the Cybex (machine) leg press (1RMs) and 343.4 ± 123.4 lbs on the Cybex (free-weight) leg press (1RMs). There was a significant difference between the Cybex (free-weight) leg press and the Cybex leg press (p<.001). The correlation for these two types of lifts was r=0.88. There was a significant difference between the free-weight bench press and the Paramount seated chest press (p<.001). The correlation for between the two types of lifts was r=0.93. / School of Physical Education, Sport, and Exercise Science

INTRODUÇÃO. A força muscular e o equilíbrio do tronco são os aspectos mais importantes para a determinação da classificação funcional de atletas de basquetebol em cadeira de rodas. O objetivo deste estudo foi analisar e correlacionar a força muscular e os limites de estabilidade do tronco de acordo com a classificação funcional para atletas de basquetebol em cadeira de rodas. MÉTODOS. Quarenta e dois atletas, com classificação funcional homologada pela federação paulista da modalidade, distribuídos nas quatro classes do Basquetebol em Cadeira de Rodas (Classe 1 n= 11; Classe 2 n=11; Classe 3 n= 9; Classe 4 n=11) com média de idade de 28,3±7.4 (16-46) anos, do sexo masculino tiveram a força muscular e equilíbrio de tronco avaliados. A força do tronco foi avaliada nos músculos extensores e flexores utilizando o dinamômetro isocinético Biodex® de forma isométrica com 15 º de amplitude. Os atletas realizaram uma série de 10 repetições com 15 segundos de descanso entre cada repetição. O equilíbrio do tronco foi avaliado no equipamento Balance Master® e o teste utilizado foi o de Limites de Estabilidade (LOS) de forma adaptada. Os atletas, sentados em um banco, realizaram movimentos voluntários do tronco em oito direções no plano frontal e lateral. Os movimentos foram feitos no sentido horário, ao redor de um perímetro, visualizado pelo paciente em um monitor e que representa o limite de 100% de deslocamento dado pelo equipamento. RESULTADOS. Considerando a distribuição dos atletas nas classes, houve diferença significativa na comparação dos índices de força muscular e equilíbrio entre as classes 1x3; 1x4 e 2x4. Houve correlação negativa (moderada) entre a força muscular do tronco em flexão e o DM (r=-.68, p=.02. Houve correlação positiva (forte) na classe 3 da força muscular do tronco em extensão e o DM (r=.92 p=0,001). CONCLUSÃO. A força muscular isométrica de flexão e extensão do tronco e os índices de equilíbrios de VD e DM nas direções anterior, posterior aumentam progressivamente com as classes e apresentam maiores diferenças na comparação entre as classes 1 e 3 e 1 e 4 e 2 e 4. Não houve correlação entre a força muscular isométrica dos flexores e extensores do tronco e os limites de estabilidade de acordo com a classificação funcional do BCR / BACKGROUND. Trunk muscle strength and balance are very important in defining the class of wheelchair basketball (WCB) athletes. This study aims to correlate and analyze trunk muscle strength and balance among high-performance Brazilian WCB athletes with their functional classification. METHODS. Forty-two male athletes of mean age 28.3±7.4 years (16-46) were divided into four groups based on WCB classes as follow: class 1 n=11; class 2 n=11; class 3 n=9; and class 4 n=11. The athletes performed a set of 10 repetitions of trunk flexion and extension with 15 seconds of rest between each repetition using the BiodexR isokinetic dynamometer in isometric form, with amplitude 15° to evaluate trunk muscle strength. In order to evaluate trunk balance, using the Balance Master® equipment and the Limits of Stability test (LOS), the athletes made voluntary trunk movements in eight directions (clockwise) in the frontal and lateral planes while seated on a bench. During the test, the athletes could view the movements on a monitor that represented the 100% displacement limit given by the equipment. RESULTS. There were significant differences in comparisons of trunk muscle strength and LOS in the classes 1vs.3, 1vs.4 and 2 vs.4. There was moderate negative correlation between trunk muscle strength in flexion and maximum excursion (r=-0.68; p=0.02). There was a strong positive correlation in class 3 between trunk muscle strength in extension and maximum excursion (r=0.92;p= 0.001). CONCLUSION. There was no correlation of isometric trunk muscle strength in flexion and extension and LOS indices, according to the functional classification of the WCB athletes

Thesis (M.Tech.: Chiropractic)- Dept. of Chiropractic, Durban University of Technology, 2008. x, 52 leaves, Appendices A-E, [25] leaves. / To determine whether a relationship exists between core stability and bowling speed in Action Cricket bowlers. Methods: Thirty asymptomatic indoor Action Cricket fast and fast-medium bowlers were divided into two groups of 15 each, with Group A having well-developed core stability and group B having poorly-developed core stability. The concept of matched pairs was used for age and cricket experience in order to maintain homogeneity between the groups. The core stability and bowling speed of each participant was measured using a pressure biofeedback unit (PBU) and speed sports radar respectively. SPSS version 15.0 was used to analyse the data.

Dissertation submitted in partial compliance with the requirements for the Master’s Degree in Technology: Chiropractic at the Durban University of Technology, 2009 / Objectives: When we consider the body position of a field hockey player, the lumbar spine is always in a flexed position, which combined with rotational movements during various hitting and pushing techniques, increases the strain upon the spine and surrounding muscles, thus leading to low back pain. To determine the relationship between core strength and trunk extensor endurance relating to the incidence of acute low back pain in field hockey players. Project Design: The research project was in the form of a quantitative cross-sectional study, using human subjects. Setting: The research project occurred during the field hockey season (2008) with players who had acute low back pain. The players were clinically assessed and subdivided into necessary groups at the Chiropractic Day Clinic at the Durban Institute of Technology. Subjects: Adult, male patients, aged between 18 and 30 years of age, playing premier field hockey. Out of the thirty players, 12 players have played in the National u/21 squad, 7 players have played in a Junior National team and 11 players have played senior provincial field hockey. Outcome measure: This included three tests. Firstly, the absolute difference of pressure from the reference value of 70mmHg (prone) and 40mmHg (supine) was used as the outcome measure on a Pressure Biofeedback Unit and length of time (in seconds), a correct contraction of the core stability muscles was maintained. Secondly, the length of time (in seconds) for Trunk Extensor Endurance. Thirdly, repeated measures for NRS-101 and Quebec Back Pain Disability Scale for the duration of the research period. v Results: It was found that there was no statistical evidence or convincing trend to show that the training programmes (core stability and trunk extensor endurance) increased the subjects’ core strength or trunk extensor endurance in the time allocated, although there seemed to be a placebo effect in the Trunk Extensor Group, which showed improvement in some of the core stability outcomes. There was statistical evidence that the intervention (training programmes) reduced pain, according to the Quebec Back Pain Disability Scale (Quebec) score over time, and a non-significant trend suggested this according to the Numerical Rating Scale-101 (NRS). Since both groups’ NRS and Quebec scores were not significantly different at baseline, the difference can be attributed to the effect of the intervention. Conclusions: The results of this study found that the Trunk Extensor Endurance Group, that performed the trunk extensor endurance training programme, yielded better results in core stability and trunk extensor endurance. However, the Core Stability Group, that performed the core stability training programme, showed a quicker reduction in pain levels during the three week intervention period. Therefore, by combining both training programmes, future rehabilitation of athletes suffering from acute low back pain will be more successful. Sport performance of the athletes (field hockey players), through the proponents of swiss ball training, will also improve.

published_or_final_version / abstract / toc / Psychology / Master / Master of Philosophy

Eccentric overload in training settings utilizes loads higher than concentric one repetition maximum (1RM). There is no clear definition of eccentric “failure” or 1RM using conventional weights, so eccentric 1RM is estimated to be between 145-190% concentric 1RM. Historically, the highest intensity used for eccentric overload is typically 120% of concentric 1RM despite little research using conventional weights with higher eccentric intensities. The purpose of this study was to conduct an exploratory neuro-mechanical analysis of different intensities of elbow flexors eccentric overload using free weights by examining angular kinematics during contraction. Twenty male participants with weight training experience had unilateral concentration curl isometric peak torque assessed on a Humac Norm Dynamometer and concentric 1RM assessed with dumbbells while biceps brachii electromyography (EMG) and elbow joint angle were recorded. Angles were recorded using a custom made electrogoniometer and elbow joint torque was estimated using inverse dynamics. Participants were randomly assigned in counter balanced order to perform eccentric actions at 120%, 140%, 150%, 160% and 170% concentric 1RM with 4 minutes rest between. Variables included peak torque, angular velocity at peak torque, impulse, power, mean EMG, and EMG normalized to peak. Data were analyzed using repeated measures ANOVA or a Friedman test. Angular velocity at peak torque was significantly lower for 120% (65.3 ± 40.8°/s) compared to all other conditions (range: 65.3 ± 40.8 to 162.1 ± 75.2°/s; p<0.01). Peak torque for all conditions (range: 98.2 ± 16.2 to 108.2 ± 21.6 Nm) was significantly higher than isometric peak torque (77.4 ± 16.8Nm; p<0.05). Peak torque at 160% (108.2 ± 21.6Nm) was significantly higher than at 120% (98.2 ± 16.2Nm; p<0.05). Power for 140-170% (range: 166.2 ± 85.7W to 265.8 ± 111.3W) was significantly higher than power at 120% (79.9 ± 66.8W; p<0.05). Impulse was highest at 120% (56.1 ± 54.6Nms) compared to all other conditions (range: 56.2 ± 54.6 to 9.6 ± 3.8Nms; p≤0.05). Impulse at 140% (20.6 ± 11.8Nms) was significantly higher than 170% (9.6 ± 3.8Nms; p<0.05). Isometric mean EMG (0.792 ± 0.285 mV) was significantly higher than all eccentric conditions (range: 0.654 ± 0.313 to 0.533 ± 0.259mV; p<0.05) with no difference between eccentric conditions for mean EMG or EMG normalized to peak. It was concluded that compared to 120%, eccentric overload with intensity ranging from 140-170% concentric 1RM involves minimal increases in peak torque and no change in EMG activation. Intensities above 120% enhance power and decrease impulse. This research has implications on future training prescription of eccentric exercise.

The purpose was to examine actual force (AF) productions of males for accuracy during leg extensions when given a random desired force (DF) ranging from 10-90% of maximal force (MF). Thirty males ranging from 18 to 30 years of age (M = 21.99 + 3.04), who had no previous experience with the test equipment, went through 9 randomly ordered submaximal efforts followed by a maximal effort. Correlations between AF and DF were high (r > .79) and test-retest was consistent between AF (r = .87) and MF (r = .90). Participants consistently undershot DF on both test and retest from 20-90% and overshot DF only at 10%. Power functions revealed exponents of less than 1, indicating that AF grows slower then DF for both test .70 (.95 CI = .63 - .77) and retest .66 (.95 CI = .60 - .73). The results replicate a prior study by Jackson, Martin, Koziris, Ludtke, and Dishman (2001) that used incremental rather than random increases in DF.

The purpose of this study was to determine the effects of weight loadings and repetitions, frequency of exercise, and knowledge of theoretical principles of weight training on changes in muscular strength. Another purpose was to analyze these effects and determine implications for coaches, physical educators, physical therapists, and others interested in determining the optimum combination of the three variables for increasing muscular strength.

The purpose of this study was to examine the acute effects of cycling exercise at different intensities and rest intervals on strength performance. Ten males, engaged in concurrent training for at least one month prior to testing, comprised the subject group for this study. Results show only leg press torque and leg press work to be decreased after cardiorespiratory exercise of moderate intensity. Leg extension average power, chest press torque, chest press power, and chest press work after cycling were not decreased from pre-exercise values. No significant effects were found for exercise intensity, testing times, or intensity by testing times. These results indicate that lower body strength is decreased by cycling and that one hour is not sufficient to restore leg strength.