Secondary warm-up following stretching on vertical jumping, change of direction, and straight line speed

The aim of this study was to build on previous conflicting research on performance following stretching and secondary activity post-stretching. Using a randomized, cross-over design, 15 male participants completed a 5-min warm-up jog, followed by a maximal vertical jump (VJ1) and a repetitive five-repetition jump (VJ5) on a force mat, an intervention (static stretching, dynamic range of movement stretching, or no-stretching control), then a second maximal vertical jump and repetitive five-repetition jump, followed by a change of direction test (505 test) and a straight line sprint (20-m). Two-way analysis of variance with repeated measures showed significant time and group × time interaction effects for both mean maximal VJ1 and VJ5 jump heights (P<0.001). Time course changes showed VJ1 jump height following static stretching was significantly reduced (7%) compared with the dynamic and control conditions, which improved by 5.0% and 3.9% (P = 0.02 and P = 0.04) respectively. Following the second bout of movement activity, VJ1 jump height had improved, but was not significantly different from baseline value (P = 0.11). Similarly, VJ5 jump height following static stretching was significantly reduced (6.2%) compared with the dynamic and control conditions, which showed improvements of 6.7% and 7.5% (P = 0.04 and P = 0.01) respectively. After the second bout of movement activity, mean VJ5 jump height for the static stretching group returned to baseline values (P = 0.84), while further improvements were observed in the dynamic (3.2%) and control groups (2.2%) (P = 0.01 and P = 0.04 respectively). Significant improvements in the 505 test were observed in the dynamic and control conditions, in both legs (range 2.45-3.67%; P<0.001), compared with the static stretching condition. Although sprint time improved following the second bout of movement activity, no differences were observed in the 20-m sprint between conditions. The results of this study confirm previous findings that static stretching reduces vertical jump height that is not reversed with follow-up movement activity. Moreover, the results show that activities requiring rapid changes of direction and speed may also be affected if preceded by a bout of static stretching, and is not reversed with follow-up movement activities.