The effect of static and dynamic stretching exercises on the maximal isokinetic strength of the knee extensors and flexors

Warm-up and stretching exercises constitute an essential part of physical preparation before any athletic event. The aim of this study was to examine the acute effect of static and dynamic stretching exercises on maximal isokinetic torque of knee extensor and flexor muscles. Thirty-two (n = 32) physical education students aged 19-22 years were asked to perform three different protocols consisting of A) warm-up, B) warm-up and static stretching and Q warm-up and dynamic stretching exercises, on three non-consecutive days. Each treatment was followed by measurements of knee extensor and flexor muscles maximal concentric torque on an isokinetic dynamometer at 60 and 180 degrees/s. ANOVA for repeated-measures revealed significant differences in maximal torque following the different protocols. Tukey's post hoc tests showed a reduced torque for knee extensor (p < 0.01) and knee flexor muscles (p < 0.01) at both velocities when static stretching exercises preceded the test. These findings indicate the negative influence of the static stretching exercises on maximal isokinetic torque production, while dynamic stretching approach does not seem to have any inhibitory effect.