Acute effects of stretching and/or warm-up on neuromuscular performance of volleyball athletes: a randomized cross-over clinical trial

The purpose of this study was to analyze the acute effects of stretching and warm-up (isolated or combined) on electromyographic response and functional performance of college volleyball athletes. This is a randomized cross-over clinical trial composed of 11 male athletes (21.54 +/- 2.42 years; 1.79 +/- 0.09 m; 21.80 +/- 1.50 kg/m(2)), members of the indoor volleyball team of the institution. All individuals underwent five randomly selected interventions, with a 7-day washout period: control, active warm-up, static stretching, warm-up followed by stretching, and stretching followed by warm-up. The athletes were assessed before and after interventions for the following variables: root mean square (RMS) signal during vertical jump through electromyographic activity of the rectus femoris and biceps femoris muscles and the vertical jump height; lower limb relative power; agility and velocity through functional tests. There were no significant changes on RMS values during vertical jump between the different interventions for the rectus femoris (P=0.659) and the biceps femoris (P=0.530) muscles, and functional tests (P >= 0.05). In conclusion, the effect of a single session of self-stretching and active warm-up (isolated or combined) does not interfere in the performance of volleyball college athletes.