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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

A correlation study between 10 and 15 meter sprint and vertical jump height in young female teamgymnasts

Svensson, Hannah January 2016 (has links)
Background: Teamgym is originally from Scandinavia and the first competition was held in Finland in 1996. The sport includes parts such as trampette, tumbling and floor programs which is performed by the whole team which often consists of six to twelve gymnasts. Trampette and tumbling program consists of three series of tumbles and vaults performed by six gymnasts of the team. The floor program is three minutes long and performed by the team. Female elite gymnasts are often short, lightweight and have a good strength and power and are very flexible and limber. Jumping movements are common in this sport especially to vault and floor programs. It is also preferable that the gymnasts achieves a high sprint speed in order to carry out the movements that are included in the sport. Plyometric training along with resistance training has proven to have positive effects on the gymnasts jumping ability. Especially the jumping ability is incredibly important for a gymnast and for its development in the sport. Plyometrics improves not only the acceleration during the sprint, but also increases the athlete’s strength in the lower extremity. Very few previous studies have been done on gymnastics, particularly in teamgymnastic. Aim: The aim of this study was to investigate if there is any linear correlation between vertical jump height and 10 and 15 meter sprint in teamgym gymnastics. Method: 17 young female teamgymnasts, 12-17 years old, were tested in 10 and 15 meter sprint and two different vertical jumps, countermovement jump with arm swing (CMJa) and squat jump (SJ). The highest was correlated with the fastest sprint time. To analyze the correlation between vertical jumps and sprint the Spearman’s rank correlation (rs) was used. Result: CMJa shows a moderate negative correlation to 10 meter sprint (rs = -0.447) and CMJa also shows moderate negative correlation to 15 meter sprint (rs = -0.488). SJ shows a weak negative correlation to 10 meter sprint (rs = -0.23). SJ also shows weak negative correlation to 15 meter sprint (rs = -0.16). When controlling for the weight, SJ and both sprints went from a weak correlation to a strong correlation. Conclusion: The strongest correlation was found between CMJa and 15 meter sprint. When controlling for the weight, SJ and both sprints went from a weak correlation to a strong correlation. The result showed that the test subjects jumped higher during CMJa than during SJ, with a median of 36.0 compared with 30.0 centimeters. No previous studies have examined these variables and their relationship on teamgymnasts. Further research should be done on the teamgymnasts, since very little previous research has been done in this area.
12

The relationship between power output in different squats and sprint performance in young male soccer players

Emanuelsson, Eric January 2015 (has links)
Background: Research has displayed a strong relationship between lower body strength and power, both in eccentric-concentric and concentric only exercises, in male soccer players. However the relationship between different types of squats and sprint performance has not been studied thoroughly in young male soccer players. Aim: The aim of the study was to investigate the relationship between sprint performance and power output in different squat variations in young male soccer players. Methods: Eleven young male soccer players, 17-19 years old, were tested in 1 repetition maximum (1RM) squat (S), 1RM concentric squat (CS) and in 5m, 10m, 15m and 30m sprint performance. Power testing in S and CS were performed at 30%, 50% and 70% of 1RM and registered as absolute power (W) and as power relative to body weight (W/kg). Results of the power output in S and CS were correlated with sprint performances. Correlations of rs ≥0.6 were considered to indicate a strong relationship. Results: There were strong correlations (rs = -0.61 to -0.68) between CS power output at 50% of 1RM, relative to body weight (W/kg), and all the sprint distances. S power output at 50% of 1RM, relative to body weight (W/kg), showed strong correlations (rs = -0.64 to -0.67) to 5m, 10m and 15m sprint. The only absolute power output (W) value to strongly correlate (rs = -0.62) with sprint performance was S at 50% of 1RM and 5m sprint. Conclusion: Both S and CS performance showed strong correlations with sprint start performance in young male soccer players. In conflict with previous research, this study showed a stronger correlation between CS and 30m sprint performance than S did. The results support previous findings that strength and power divided by body weight are stronger associated with sprint performance than absolute measures are. Both S and CS should be performed in the general strength training program to improve maximal strength and power, and thereby enhance soccer performance.
13

Samband mellan vertikal hopphöjd och sprint hos unga kvinnliga gymnaster : Kandidatuppsats i Biomedicin - inriktning fysisk träning 15hp

Johnsen, Caroline January 2015 (has links)
Gymnastik är en sport som kräver bra sprint-och hoppförmåga. Det är känt att högre sprinthastigheter kan leda till högre vertikal hopphöjd, ett måste för svårare gymnastiska moment. Plyometrisk träning är principen om högintensiva hoppövningar som tillämpar Stretch Shortening Cycle (SSC). En förbättrad SSC-förmåga kan bidra till ökad kraftutveckling och förmågan att uppnå högre vertikal hopphöjd och sprinthastigheter. Syftet med studien var att undersöka om det fanns samband mellan vertikala hopphöjden och sprinttiden vid 30 meter hos unga kvinnliga gymnaster. Sexton kvinnliga gymnaster testades i vertikal hopphöjd genom Squat jump (SJ), Countermovement jump (CMJ) och Free jump (FJ) och sprint 30 meter, varav femton gymnasters resultat har analyserats. För att studera sambandet mellan SJ, CMJ, FJ och sprinttiden vid 30 m gjordes korrelationer (Spearman, rs). En korrelation mellan 0.4 och 0.6 är medelstarkt, allt där över är starka korrelationer och allt under är svaga korrelationer. Samtliga hopp visade på en stark negativ korrelation med sprinttiden vid 30 meter, SJ rs= - 0,68, CMJ rs= -0,76, FJ rs= -0,69. Starkaste korrelationen fanns mellan CMJ och 30 meter sprint. Den starka negativa korrelationen tyder på att en högre vertikal hopphöjd har ett starkt samband med sprinthastigheten.
14

Comparação de diferentes intervalos de recuperação aplicados aos testes de sprints repetidos em futebolistas

Pereira, Julimar Luiz January 2013 (has links)
Orientador : Prof. Dr. Sérgio Gregório da Silva / Tese (doutorado) - Universidade Federal do Paraná, Setor de Ciencias Biológicas, Programa de Pós-Graduaçao em Educaçao Física. Defesa: Curitiba, 28/06/2013 / Bibliografia: f. 132-145 / Área de concentraçao: Exercício e esporte / Linha de pesquisa: Desempenho esportivo / Resumo: O objetivo deste estudo foi verificar o efeito de diferentes intervalos de recuperação no desempenho em testes de RSA para futebolistas. Vinte e nove futebolistas sub-17 (16,0 ± ,55 anos; 1,74 ± 6,5 m; 68,9 ± 7,4 kg; 55,1 ± 2,7 ml.kg.min-1) realizaram o teste de 10x30 metros com quatro intervalos entre os sprints: 10, 20, 30 e 60 segundos com espaço de uma semana entre cada testagem. Previamente os atletas ainda realizaram testes de velocidade em 10 e 30 metros, salto vertical, VO2max e avaliação da composição corporal. Aplicação do teste multivariado de Wilks Lambda apontou diferenças significativas na médias observadas a partir do segundo sprint entre os intervalos de 10 e 20 segundos para 30 e 60 segundos (p?0,000; ?=,514; F=8,211); diferenças mais significativas foram observadas a partir do terceiro sprint entre todos os intervalos (p?0,000; ?=,143; F=52,047). Correlação de Pearson identificou correlação entre as variáveis da RSA (tempo médio, potência média e máxima) e velocidade nos 10 e 30m e salto vertical em todos os intervalos. Os desempenhos nos quatro testes apresentaram correlação entre si. O maior tempo médio (4,51 ± ,16 segundos, ?= ,068, F=119,05) e o maior índice de fadiga (23,7 ± 7,6%) foram observados no intervalo de 10 segundos. A maior potência (15,05 ± 1,51 w.kg-1) a melhor média de potência (13,72 ± 1,15 w.kg-1) e o menor índice de fadiga (5,4 ± 1,6 %) foram observadas no intervalo de 60 segundos. Esses dados sugerem que há um forte impacto do intervalo de recuperação no teste 10x30m, com comportamentos distintos entre as variáveis observadas nos testes de RSA. Enquanto no intervalo de 10 segundos, quedas superiores a 10% no desempenho podem ser observadas logo após o segundo sprint; no intervalo de 60 segundos essa situação não ocorre. Concluimos afirmando que intervalos mais curtos entre os sprints repetidos limitam a potência observada nos testes de RSA e apresentam fadiga mais intensa, provavelmente em função da acidose metabólica ou pela depleção dos substratos energéticos envolvidos nos processos de predominância anaeróbia. / Abstract: The aim of this study was to investigate the effect of different rest intervals on performance in tests for RSA in soccer players. Twenty-nine players under-17 (16.0 ± 55 years; 1.74 ± 6.5 m, 68.9 ± 7.4 kg, 55.1 ± 2.7 ml.kg.min-1) performed testing with four 10x30m intervals between sprints 10, 20, 30 and 60 seconds, with one week between each test. Previously athletes also performed speed tests on 10 and 30 meters, vertical jump, VO2max and body composition assessment. Wilks' Lambda multivariate test showed significant differences in means observed from the second sprint intervals between 10, 20 and 30 seconds to 60 seconds (p?0,000; ?=,514; F=8,211) differences were seen from the third sprint between all time intervals p?0,000; ?=,143; F=52,047). Pearson's correlation identified an correlation between the variables of RSA (average, maximum and average power) and speed in the 10 and 30m and vertical jump in all ranges. The performances in the four tests showed correlation. The time higher mean (4.51, ± ,16 sec, ?= ,068, F=119.05) and greater fatigue index (23.7 ± 7.6%) were observed within 10 seconds. The higher power (15.05 ± 1.51 w.kg-1) the best average power (13.72 ± 1.15 w.kg-1) and lower fatigue index (5.4 ± 1.6%) were observed within 60 seconds. These data suggest that there is a strong impact of the recovery interval test 10x30m, with different behaviors between the observed variables in tests of RSA. While within 10 seconds falls more than 10% in performance may be observed shortly after the second sprint, in the range of 60 seconds this situation does not occur. We conclude by stating that shorter intervals between repeated sprints limit power observed in tests of RSA and present the most severe fatigue, probably due to metabolic acidosis or the depletion of energy substrates involved in the processes of anaerobic predominance.
15

Stratégie de performance et régulation de la fatigue musculaire en sprints répétés

Rousseau-Demers, Marie 10 July 2019 (has links)
Les entraînements en sprints répétés et de courte durée sont bien connus du domaine des sports collectifs. En effet, la capacité à répéter des sprints est une composante physiologique ayant une forte corrélation avec la performance sportive. Ayant un impact sur l’amélioration de la filière aérobie et l’augmentation de la vitesse maximale, ce type d’entraînement consiste à effectuer un sprint, à récupérer de façon partielle puis à sprinter de nouveau (Bishop & Castagna, 2002).Cette technique peut être effectuée de plusieurs façons, par exemple sur ergocycle, sur piste d’athlétisme ou sur tapis roulant. Toutefois, les dernières recherches montrent que les athlètes utiliseraient des stratégies d’anticipation, de façon consciente ou non, qui pourraient altérer la qualité de l’entraînement et ainsi potentiellement nuire aux adaptations chroniques. Actuellement, il y a très peu d’études qui ont étudiées le phénomène d’anticipation et de régulation de l’intensité lors d’entraînement en sprints répétés. À l’aide de l’électromyogramme et de mesures de fatigue centrale et périphérique, nous avons examiné les effets de ce type de séance d’entraînement sur la fatigue musculaire et déterminé une des origines probables de ce phénomène. Nos résultats montrent une régulation de l’intensité à laquelle une personne s’exerce lors de sprints répétés. La raison première serait de limiter la fatigue périphérique extrême pouvant augmenter le risque de causer des dommages internes. De plus, notre recherche montre que le phénomène d’anticipation serait régulé grâce au contrôle exercé par le système nerveux central. Les séances d’entraînement en sprints répétés pourraient amener les athlètes à améliorer leur seuil de fatigue et ainsi optimiser leurs entraînements et améliorer leurs performances. / Repeated sprints ability (RSA) trainings are well known in team sports. Indeed, the ability to repeat sprints is a physiological component that has a strong correlation with performances. Having an impact on improving the aerobic chain and increasing the maximum speed, this type of training consists of sprinting, recovering and sprinting again.(Bishop & Castagna, 2002). This technique can be performed in several ways, for example on an ergocycle, track or treadmill. However, the last research shows that athletes would use pacing strategies consciously or not, which could alter the training quality and there by training adaptations. Currently, there are very few studies that have studied the phenomenon of pacing during repeated sprints. We combined the electromyogram and a muscle stimulator to examine the effects of this type of training on muscle fatigue. Our results show that there is pacing during RSA trainings. The first reason would be to limit extreme muscle fatigue that may increase the risk of causing internal damage. Moreover, our research shows that the phenomenon of anticipation is regulated by the central nervous system. Training via repeated sprints could lead athletes to improve their fatigue threshold and thus optimize their training and improve their performances.
16

Periodization For Sprinters

Dias-Johnson, Georgy January 2010 (has links)
No description available.
17

An assessment of video motion analysis : variability, reliability, camera orientation and extrapolation

Salo, Aki Iikka Tapio January 1999 (has links)
No description available.
18

A biomechanical and physiological evaluation of combined uphill-downhill sprint running training

Paradisis, Giorgos P. January 1998 (has links)
No description available.
19

Influence of average pedalling rate upon the magnitude of the mechanical and biochemical changes arising from high-intensity exercise

Cherry, Paul Warren January 1997 (has links)
The process of fatigue during 30 s of high-intensity exercise results in rapid and substantial mechanical, electrical and biochemical changes in muscle fibres. This thesis describes a series of experiments, performed upon a friction-loaded cycle ergometer, which investigated whether the magnitude of the mechanical and biochemical changes is affected by changes in average pedalling rate. The ability to generate peak power in a subsequent sprint of 6 s duration was used to assess the magnitude of the mechanical changes. Changes in the concentrations of blood and muscle metabolites pre- and post-exercise permitted some of the biochemical changes to be measured.
20

Hur gör vi med språket? Språkbruk och språkutveckling i språk- ochämnesintegrerad biologiundervisning

Hildingsson, Linus January 2022 (has links)
Biologiundervisning på ett för elever och lärare främmande språk är utmanande och ställer krav på språkliga och kognitiva förmågor. I denna studie intervjuas fyra biologilärare i grund- och gymnasieskolan om hur de ser på olika språkbruk i undervisningen samt vilka språkutvecklande arbetssätt de använder. Intervjumaterialet analyserades utifrån fenomenografi för att beskriva variationen av uppfattningar. Resultatet visar två synsätt bland lärarna: 1) skol- och ämnesspråket är viktigast och undervisningen bör i huvudsak organiseras kring utvecklandet av dessa, 2) vardagsspråket är en nödvändig förutsättning för skol- och ämnesspråket, undervisningen bör därför först organiseras kring utvecklandet av detta. Första gruppen lärare tenderar att förutsätta tillräckliga språkfärdigheter hos eleverna. Andra gruppen lärare gör färre sådana antaganden. Första gruppen lärare använder transspråkande, struktur samt elev till elev-stöd som språkutvecklande arbetssätt. Andra gruppen lärare använder utöver dessa även multimodalt lärande. Utifrån resultatet diskuteras utmaningar och fördelar kring olika sätt att organisera undervisningen i relation till språkutveckling.

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