Shorter static stretching volume does not impair isokinetic muscle strength

Abstract

Coaches and athletes in warm-up routines for preventing muscle injuries during exercise, and hoping for improving muscle performance commonly incorporate static stretching. However, static stretching exercises usually impairs muscle performance. Although static stretching exercises impair muscle performance, there is a greater variability of the evidence in static stretching induced impairmentswhen the static stretching volume are less than 90 seconds per muscle group. In this sense, this study was designed to compare different static stretching volume on extensor and flexor knee peak torque. Twenty-one physically active men visited the laboratory five times for performing the familiarization process and experimental procedures. In each experimental procedure, the individuals performed an isokinetic testpreceded byactive warm-up and static stretching. The angular velocities of isokinetic tests were 60°/s, 180°/s, and 300°/s. The warm-up routines were: active warm-up on cycle ergometer + no stretching; active warm-up on cycle ergometer + twenty seconds of static stretching; active warm-up on cycle ergometer + forty seconds of static stretching; active warm-up on cycle ergometer + sixty seconds of static stretching. The stretching exercises were performed in knee extensors and knee flexors. No differences were showed between all protocols to knee extension peak torque at angular velocities 60°/s (F=0.545, p=0.653), 180°/s (F=0.082, p=0.969), and 300°/s (F=0.230, p=0.875). Moreover, knee flexion peak torque did not show difference between all protocols at angular velocities 60°/s (F=0.100; p=0.960), 180°/s (F=0.036, p=0.991) and 300°/s (F=0.057, p=0.982). This study provides evidence that static stretching performed until 60 seconds incorporated in warm-up routine did not impair extensor and flexor knee peak torque.