The Acute Effects of Static Stretching on Leg Extension Power:Quadriceps Torque Production After a 30-Second Static Stretch Versus No Stretch

Introduction: Traditionally, static passive stretching has been used by coaches and athletes as a warm-up technique in an attempt to promote better performances. However, the results of recent research have shown that passive muscle stretching can diminish the peak force output of subsequent maximal concentric contractions of the quadriceps. Aside from clinicians’ benefits, athletes competing in a competitive sport which involves explosive contractions (i.e. power lifting) would benefit from knowing if preexercise stretching of a particular muscle group will temporarily compromise its ability to produce a maximum force. The purpose of our study was to determine the effects of static stretching on peak torque production of the quadriceps. Our hypothesis states that static stretching would cause a decrease in peak torque and mean power output due to stretch-induced changes in the muscle fibers of the quadriceps. Experiment: The participants of this study consisted of forty-seven healthy male and female college students. Isokinetic quadriceps maximum torque of the subjects’ dominant leg was measured prior to and after a thirty second passive static stretch. Results: There was no significant difference between the subjects’ results prior to and after the thirty second stretch intervention. Further data analysis showed no significant difference in power values between age, height, weight or sex.