The ability to produce power during competition is essential. Football requires explosive power in order to get off the ball faster, increase speed of the first step, and increase the height of the vertical jump. Most strength training professionals use the back squat to increase power of the lower extremities; however, as large forces are placed on the back, athletes are at greater risk for injury. The trap bar dead lift is similar to the back squat in movement and form, but the trap bar dead lift reduces the force on the lower back. After testing for maximum vertical jump,athletes at Timpview High School participated in a strength program using either back squats or trap bar dead lift for seven weeks. A pre-test, mid-test and post-test were performed to calculate the increase in maximum vertical jump, if any. It was found that neither lift was significantly different than the other when testing for maximum vertical jump. These results will allow strength training professionals to use the trap bar dead lift instead of the back squats in subjects similar to those participating in the study.

This study investigated changes in maximal jump performance in response to match play induced fatigue. During six sets of tournament match play, seven National Association of Intercollegiate Athletics women’s volleyball athletes accumulated a mean Player Load of 758.6±216.89 au (measured via microsensor accelerometry), and mean session rate of perceived exertion of 1184.1±363.2. Repeated measures ANOVAs were used to identify change with Hedge’s g effect sizes used to assess magnitude of change. Short recovery stress scale results indicated elevated stress (ES=1.401 to 1.588) and decreased recovery (ES = -1.358 to -1.848) 24 hours post-match, trending towards baseline 48 hours post-match. Countermovement jump height (CMJH) decreased immediately post-match (p<0.01, ES= -0.216), partially recovered Post24 (p=0.109, ES=0.130), and fully recovered by Post48 (p < 0.01, ES=0.216). It was concluded that match-play may have contributed to the observable decline in post-match maximal jump performance, and CMJH testing may be an effective assessment of acute neuromuscular status.

Although the vertical jump has long been an accepted and valuable test of explosive strength and physical ability, the major factors affecting performance have not been isolated. This study was designed to investigate vertical-jump performance in relation to certain foot measurements. Two ratios comprised of heel/foot length and arch length/foot length were correlated to vertical-jump performance.

Title: The Effect of Postural Therapy Using Posturomed on Jump in Basketball. Objectives: The aim of the thesis is to assess what effect the state of postural stabilization has on the jump height in basketball, to capture the level of postural stabilization before and after the 6-week proprioceptive postural therapy on Posturomed and to find out whether the jump height in probands changes after this therapy. Methods: The thesis included 30 probands - basketball players. 15 probands were assigned to the experimental group and 15 other probands were assigned to the control group. All probands underwent both the initial and the final jump height measurement. Each proband had 3 attempts, out of which the highest performance was recorded. The probands of the experimental group participated in a 6-week postural therapy. The therapy was carried out according to the concept of postural therapy on Posturomed by dr. Rašev. The data was evaluated in program Microsoft Office Excel. For the calculation of the unpaired t-test, statistical program SPSS was used. Results: Measurements confirmed the positive effect of the therapy on Posturomed on the jump height. The experimental group achieved a statistically significant difference in the jump height against the control group. Keywords: Vertical jump, basketball,...

Title: Vertical jump comparison of women's volleyball players Objectives: The aim of this work was to coparison of vertical jump, postural stability and body composition of women's volleyball players before and after season 2012/2013. During the season there was a deliberate intervention to develop explosive power. By the comparing the input and output of results we conclude that the training developed or didn't develop explosive power of the lower limbs, and that had an effect on body composition and stability. Methods: The study included 10 women from 2. Volleyball League (n=10 , age = ± 20,6 years, height = ± 172,7 cm, BMI = ± 0,19 kg/cm2 ). For input and output testing, we used three different tests. First, we measured body composition, then postural stability (1) narrow standing with eyes open (the US-OO), (2) narrow standing with eyes closed (the US-ZO), (3) standing on the right lower limb "flamingo test "(the FLA-R), (4) stands on the left lower limb (the FLA-L). Finally, the players performed six types of vertical jump. Jump with the upper limbs (V1 - Countermovement jump free arms) jump without the help of the upper limbs (V2 - Countermovement jump), jump from squatting (V3 - Squat jump), when the whole movement only made up, without countermovement, block jump (V4 - Block), moving one...

Title Acute effect of static and dynamic stretching on vertical jump. Objectives The aim of this thesis is to assess whether it is better to warm up by static or dynamic stretching in order to improve performance in the vertical jump. Methods The first part of this thesis is theoretical and is the basis for measurement, which is described in the second part. The tested set consists of ten women volleyball players. Each player underwent three vertical jump measurements on power plates Kistler, which recorded flight time of the player over the plates. All measurements were evaluated afterwards. Five attempts were recorded in each measurement. Measurements were carried out without stretching, after dynamic stretching and after static stretching. The thesis includes a survey that monitors the perception of the players` performance. Results Results of the total tested set measurement show that inclusion of dynamic stretching during the warm up leads to a slight decline in the physical performance. This decrease presents about 0.92%. Another conclusion of this research is that the inclusion of static stretching to the warm up also results in a slight decrease in the athletic performance. In this case the decrease is about 1.72%. In a direct comparison of these two types of stretching, the inclusion of...

Le complexe lombo-pelvi-fémoral est une zone charnière du corps humain. Son rôle d’équilibration a étédémontré à de nombreuses reprises alors que sa fonction motrice, lors de mouvements explosifs requérant uneextension totale de la chaine articulaire, a été peu étudiée. Ainsi, l’objectif de ce travail a été d’évaluer le rôle moteurdu complexe lombo-pelvi-fémoral lors d’un mouvement de squat jump. A cet effet, une approche expérimentale(cinématique, dynamique et électromyographique) couplée à un modèle de simulation du système musculo-squelettiqueont été appliqués à l’analyse du squat jump dans le plan sagittal. Les résultats montrent, dans un premier temps, que lesétudes ne prenant pas en compte le complexe lombo-pelvi-fémoral conduisent à des erreurs de surestimation du travailmécanique attribué à l’articulation de la hanche lors de squat jumps avec ou sans balancé de bras. Dans un secondtemps, il apparaît que l’extension du rachis lombaire permise par l’erector spinae participe à l’atteinte d’une hauteurmaximale de saut. Ceci confirme l’hypothèse du rôle moteur du complexe lombo-pelvi-fémoral, soulignant égalementla contribution effectrice du muscle erector spinae, qui est accrue avec l’augmentation de sa force maximale et lorsd’une flexion initiale du tronc importante. En conclusion, il semble pertinent d’intégrer le complexe lombo-pelvifémoraldans l’analyse du squat jump en vue d’ouvrir de nouvelles perspectives d’entrainement visant à l’améliorationde la détente verticale. / The lumbo-pelvic-hip complex is an important structure of the human body. Its function of balancing the bodyhas been pointed out in many studies. While its motor function has rarely been investigated, especially duringexplosive movements involving a global extension of the whole body. Thus, the purpose of this work was to evaluatethe role of the lumbo-pelvic-hip complex during squat jumping. To this end, an experimental approach (kinematics,kinetics and electromyographic) as well as a simulation model of the musculoskeletal system have been used to analyzethe squat jump in the sagittal plan. The results show, firstly that studies which do not take into consideration the lumbopelvic-hip complex, lead to an overestimation of the mechanical work attributed to the hip joint during maximal squatjumps performed arms akimbo or with an arm swing. Secondly, the extension of the lumbar spine enabled by theerector spinae activation contributes to achieve a maximal vertical jump height. This result confirms the assumptionsabout the motor function of the lumbo-pelvic-hip complex and the erector spinae. Moreover, the contribution of thismuscle is increased when its maximal strength is enhanced and when the trunk is initially flexed. In conclusion, itseems relevant to take into consideration the lumbo-pelvic-hip complex when maximal squat jumping is studied. Thiswould also contribute to new training perspectives in order to improve maximal vertical jump height.

O desenvolvimento da potência muscular e das habilidades motoras como salto vertical, velocidade de corrida e agilidade é fundamental para um bom desempenho nas modalidades esportivas coletivas, dentre elas o handebol. Os exercícios do levantamento de peso olímpico (LPO), dentre eles o hang power clean (HPC), têm sido comumente utilizados para esta finalidade; porém, pouco se sabe a respeito do efeito de diferentes intensidades de treinamento com o HPC sobre o desempenho motor de atletas. Desta forma, o objetivo do estudo foi investigar o efeito de dois protocolos de treinamento com 50% e 90% 1RM no exercício HPC nos ganhos de potência muscular dos membros inferiores, na altura do salto vertical, na velocidade de corrida, na mudança de direção e na força dinâmica máxima de jogadoras de handebol. Dezesseis atletas das categorias júnior e adulto foram divididas em dois grupos (LPO50 e LPO90; 50% e 90% 1RM, respectivamente) e submetidas a 15 sessões de treinamento durante sete semanas. Testes de potência muscular dos membros inferiores, altura do salto vertical sem e com contra-movimento (SJ e CMJ, respectivamente), velocidade de corrida, mudança de direção e força dinâmica máxima (1RM) nos exercícios meio-agachamento e HPC foram realizados pré- e pós-treinamento. Após o período de treinamento foi observado aumento significante da potência de membros inferiores no CMJ com 40% da massa corporal (MC) somente para o grupo LPO90, enquanto nenhuma alteração significante ocorreu no CMJ 60% e 80% MC para ambos os grupos. Não foram observadas alterações significantes na altura dos saltos verticais (SJ, CMJ e CMJ com diferentes sobrecargas externas) para os dois grupos; porém, a velocidade de corrida nas distâncias 0-5, 0-20 e 0-30m aumentou de forma significante e semelhante entre LPO50 e LPO90. Houve diminuição significante no desempenho da mudança de direção no teste T-40 para ambos os grupos. A 1RM no exercício HPC aumentou para os dois grupos enquanto nenhuma alteração significante foi observada para o exercício meio-agachamento. Assim, após 15 sessões de treinamento com HPC em diferentes intensidades (50% vs. 90% 1RM), pode-se afirmar que a utilização de menores intensidades promoveu adaptações positivas muito similares à utilização de maiores intensidades na velocidade de corrida e na força dinâmica máxima no exercício HPC, em jogadoras de handebol / The development of muscle power and motor skills such as vertical jump, running speed and agility is fundamental for a good performance in several team sports, among them handball. Olympic weightlifting (OWL) exercises such as the hang power clean (HPC) have been commonly used for this purpose; however, little is known about the effect of different training intensities with HPC on athletes\' motor performance. Thus, the objective of the study was to investigate the effect of two training protocols with 50% and 90% 1RM of the HPC exercise on lower limbs muscle power, vertical jump height, running speed, agility, and maximum dynamic strength of female handball players. Sixteen junior and adult athletes were divided into two groups (OWL50 and OWL90, 50% and 90% 1RM, respectively) and underwent 15 training sessions for seven weeks. Test for lower limbs muscle power, squat jump and countermovement jump height (SJ and CMJ, respectively), running velocity, agility, and maximal dynamic strength (1RM) in half-squat and HPC exercises were performed pre- and post-training. After the training period, a significant increase in lower limbs power in the CMJ was observed with 40% of body mass (BM) only for the OWL90 group, while no significant alteration occurred in the CMJ 60% and 80% BM for both groups. No significant changes were observed in vertical jumps height (SJ, CMJ and CMJ with different external loads) for both groups; however, running speed at 0-5, 0-20 and 0-30m increased significantly and similarly between OWL50 and OWL90. There was a significant decrease in agility performance for both groups. The 1RM in the HPC exercise increased for both groups while no significant change was observed for the half-squat exercise. Thus, after 15 training sessions with HPC at different intensities (50% vs. 90% 1RM), it can be stated that the use of lower intensities promoted positive adaptations in running speed and maximum dynamic strength in the HPC exercise similar to the use of higher intensities, in handball players

Combinar o treinamento de força (TF) com o de potência (TP) tem mostrado ser mais efetivo do que os treinamentos aplicados de modo isolado. Porém, não existe consenso sobre a melhor forma de combinar o TF com o TP na mesma sessão de treino. Assim, os objetivos deste estudo foram investigar e comparar o efeito da ordem de combinação do TF e do TP no desempenho da força dinâmica máxima de membros inferiores, do salto vertical, da velocidade, da agilidade, do salto em profundidade e da potência muscular de membros inferiores. Participaram 27 jogadores de futebol, os quais foram divididos em três grupos: FP (realizou todas as séries do TF e em seguida as do TP), PF (realizou todas as séries do TP e em seguida as do TF) e AA (realizou séries alternadas do TF com o TP), sendo submetidos a oito semanas de treinamento. O TF utilizou o exercício agachamento (60-80% de 1RM) e o TP utilizou exercícios de salto em profundidade. Os resultados foram: aumentos significantes na força dinâmica máxima de 48,6%, 46,3% e 53% nos grupos FP, PF e AA respectivamente; na altura do salto vertical de 13%, 14,2% e 14,7% nos grupos FP, PF e AA, respectivamente e na potência média do grupo AA (8,6%) para a carga de 40% do PC. Não foram observadas alterações no desempenho da agilidade. Com relação a velocidade, os grupos FP e PF diminuíram o desempenho nos testes de 10 e 20 metros, enquanto que o grupo AA não alterou o seu desempenho. Em conclusão, as três diferentes combinações do TF e do TP foram semelhantes em promover adaptações no desempenho de jogadores de futebol e com base nestes resultados sugere-se que a ordem de combinação do TF e do TP na mesma sessão de treino parece não influenciar o desempenho de maneira crônica / The combination of strength (ST) with power training (PT) has been shown to be more effective than the isolated methods. However, there is no consensus on the best way to combine these methods in the same training session. Thus, the purpose of this study was to compare the effect of the combination of TF and TP on performance of lower limbs maximum dynamic strength and power, vertical jump, speed, agility, and drop jump. Twenty seven soccer players participated in eight weeks of training. They were divided into three groups: FP (all TF series before TP series), PF (all TP series before TF series), and AA (alternated TF and TP series). The TF was composed of squat exercise (60-80% 1RM) and the TP used drop jumps. The results were: significant increases in maximal dynamic strength of 48.6%, 46.3%, and 53% in groups FP, PF, and AA; respectively; in vertical jump height of 13%, 14,2% e 14,7% in groups FP, PF, and AA; respectively, and in average power in the AA group (8,6%) for the load of 40% PC. No changes were observed in agility performance. The FP and PF groups presented a decrease in speed of 10 and 20 meters, while the AA group did not change. In conclusion, the three different TF and TP combinations resulted in similar adaptations in soccer players performance. Thus, it can be suggested that TF and TP training order does not seem to interfere with long term performance changes

The purpose of this dissertation was to explore the potential use of net impulse and its characteristics in vertical jumping to monitor athletes' performance status and responses/adaptations to interventions. Five variables were proposed as net impulse characteristics: net impulse height and width, rate of force development, shape factor, and net impulse proportion. The following were then examined: 1) test-retest reliability of a new approach to identify net impulse in a force-time curve and of net impulse characteristics and criterion validity of the new approach; 2) effective measures of net impulse characteristics; 3) relationships between training-induced changes in its characteristics and force production ability. The following are major findings of the dissertation. Rate of force development particularly for the countermovement jump require a large magnitude of change to overcome the variable's inherent variability. Shape factor and net impulse proportion for the static jump should be used with caution and requires further investigations. Alternative net impulse can be used interchangeably to criterion net impulse. Of the proposed net impulse characteristics, net impulse height and width and shape factor were found to contribute to countermovement jump height, whereas all the net impulse characteristics were found to contribute to static jump height. Of the characteristics found to contribute, relative net impulse height (net impulse height divided by system mass) appears to be an important characteristic to achieve a high jump height for the countermovement and static jumps and net impulse proportion for the static jump. A mechanism behind increased countermovement jump height may be an increased countermovement displacement as a result of increased force production ability. A mechanism behind increased static jump height is the increased proportion of the entire positive impulse occupied by net impulse (i.e. increased net impulse proportion). The findings of this dissertation show the possibility of the use of the net impulse characteristics to monitor athletes' performance status and responses/adaptations to interventions. However, because this dissertation was the first to explore the potential use of the net impulse characteristics for athletes' performance monitoring, the existing knowledge is still preliminary and further research is required before practical recommendations are made.