INTRODUCTION:
Stretching is very common as part of the warm-up in several sports modalities. However this practice can be negative to strength improvement and muscular power. Consequently, jump performance can be reduced after stretching exercises, depending on its duration and intensity.
OBJECTIVE:
To evaluate the acute effects of different long-term stretching times on single-leg drop jump performance.
METHODS:
The sample was composed of 16 healthy jump experienced young adult athletes. The experimental protocol consisted of performing three maximum unipodal drop jumps from a 15 cm high platform, and landing on a contact mat (Hidrofit(r)), before and after two stretching times of the triceps surae muscles (i.e. a series of 3 minutes on one side and 6 minutes on the other, with the sides being randomly chosen), using an intensity of 70-90% of their subjective perception of discomfort. An ANOVA (2x2) analysis was used to verify differences for the jump height, contact time and flexibility, using a significance level of 5%.
RESULTS:
The results showed significant differences between pre and post-stretching times of 3 and 6 minutes (P=0.002 and P=0.001, respectively). Contact time was higher only for the stretching time of 6 minutes (P=0.039).
CONCLUSION:
We conclude that stretching exercises of the triceps surae muscle, for 3 or 6 minutes, resulted in a decreased performance in the single-leg drop jump, a decrease in the vertical jump height (for 3 and 6 minutes) and contact time (for 6 minutes only), reinforcing the need for more debates in this area regarding stretching before power activities.
muscle stretching exercises; performance; plyometic training
