Objective: The purpose of this study was to investigate the relationship between absolute isokinetic knee flexion and extension strength, and sprint and agility performance in collegiate male American Football players. Materials and Methods: Twenty-six collegiate male players aged 19-27 years with at least a year of experience in playing American Football participated in the study. The players were tested for absolute isokinetic knee flexion and extension peak torque, sprint, and agility performance over two different days with at least 72-hour rest interval between tests. Knee flexion and extension peak torque were measured by means of an isokinetic dynamometer (HUMAC NORM, USA) at angular velocities of 60°·s-1 , 150°·s-1 , and 300°·s-1 for both knees. Sprint performance was evaluated with 40-yard dash and agility was evaluated with pro-agility tests, respectively. Results: The study demonstrated that 40-yard dash and pro-agility test results did not correlate with any measures of isokinetic knee flexion and extension peak torque (p>0.05). Conclusion: The results of this study indicate that isokinetic knee flexion and extension peak torque are not good predictors of sprint and agility performance in male collegiate American Football players. Additional research that will also evaluate relative (Nm.kg-1 ) isokinetic strength may be required to elucidate whether a correlation between isokinetic strength, and sprint and agility performance or perhaps other measures of performance exist for American Football players.
Amaç: Bu çalışmanın amacı, üniversiteli erkek Amerikan Futbolu oyuncularında izokinetik diz fleksiyon ve ekstansiyon mutlak kuvveti ile sprint ve çeviklik performansı arasındaki ilişkilerin araştırılmasıdır. Gereç ve Yöntemler: Çalışmaya, en az bir yıllık Amerikan Futbolu deneyimi olan 19- 27 yaş aralığında 26 erkek Amerikan Futbolu oyuncusu katıldı. Oyuncular, en az 72 saat arayla iki farklı günde izokinetik diz fleksiyon ve ekstansiyon mutlak zirve tork kuvveti, sprint ve çeviklik performansı açısından test edildi. Diz fleksiyon ve ekstansiyon zirve tork kuvveti (HUMAC NORM, USA) izokinetik dinamometre ile 60°·s-1 , 150°·s-1 ve 300°·s-1 ‘lik açısal hızlarda her iki dizde ölçüldü. Oyuncuların sprint ve çeviklik performansları sırasıyla 40 yard sprint testi pro-agility testi ile değerlendirildi. Bulgular: Çalışma, 40 yarda sprint testi ve “pro-agility” testi sonuçları ile herhangi bir izokinetik diz fleksiyon ve ekstansiyon zirve tork kuvveti arasında korelasyon olmadığını gösterdi (p>0.05). Sonuç: Çalışmanın sonuçları Üniversiteli erkek Amerikan Futbolu Oyuncularında izokinetik diz fleksiyon ve ekstansiyon zirve tork kuvvet değerlerinin, sprint ve çeviklik performansı için iyi bir belirteç olmadığını gösterdi. Amerikan Futbolu oyuncularında izokinetik kuvvet ile sprint ve çeviklik performansı arasında korelasyon olup olmadığının açıklanabilmesi için bağıl izokinetik kuvveti değerlendirecek (Nm.kg-1 ) ek çalışmalar gerekmektedir.
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