Investigation of the Relationships between Isokinetic Leg Strength, Sprint and Agility Performance in Collegiate American Football Players

Abstract

Objective: The purpose of this study was to investigate the relationship betweenabsolute isokinetic knee flexion and extension strength, and sprint and agilityperformance in collegiate male American Football players.Materials and Methods: Twenty-six collegiate male players aged 19-27 years withat least a year of experience in playing American Football participated in the study. Theplayers 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 intervalbetween tests. Knee flexion and extension peak torque were measured by means of anisokinetic 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 andagility was evaluated with pro-agility tests, respectively.Results: The study demonstrated that 40-yard dash and pro-agility test results did notcorrelate 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 andextension peak torque are not good predictors of sprint and agility performance in malecollegiate American Football players. Additional research that will also evaluate relative(Nm.kg-1) isokinetic strength may be required to elucidate whether a correlationbetween isokinetic strength, and sprint and agility performance or perhaps othermeasures of performance exist for American Football players.