Stretch and sprint training reduces stretch-induced sprint performance deficits in 13- to 15-year-old youth

The recently reported static stretching impairments found in adults have not been studied in youth. Furthermore, stretch-training effects on sprint performance are equivocal, hence the purpose of this study was to examine the effect of stretch and sprint training on the acute effects of static stretching in 13-15 year olds. A total of 48 students were randomly divided into a sprint only and a stretch and sprint training groups who performed static stretching at the beginning and middle of the speed training sessions (6 weeks). Flexibility tests and 30-m sprints were performed before and after training. Sprint performance was evaluated with and without prior stretching. A main effect indicated that prior static stretching impairs sprint times at 10 (P = 0.01) and 30 m (P = 0.0005). Both groups improved times over 10 (0.7%; P = 0.04) and 30-m (1.5%; P = 0.0007) sprint distance after training. Stretch and sprint trained participants were more resistant to stretch-induced sprint deficits with 3.2% (P < 0.0001), 3.6% (P = 0.0002) and 1.3% (P < 0.0001) faster times at 5, 10, and 30 m, respectively, than the sprint only group. In conclusion, a stretch and sprint training program in 13-15 year olds diminished the detrimental effects of static stretching compared to a sprint only training program.