A randomized trial of preexercise stretching for prevention of lower-limb injury

Abstract
POPE, R. P., R. D. HERBERT, J. D. KIRWAN, and B. J. GRAHAM. A randomized trial of preexercise stretching for prevention of lower-limb injury. Med. Sci. Sports Exerc., Vol. 32, No. 2, pp. 271–277, 2000. This study investigated the effect of muscle stretching during warm-up on the risk of exercise-related injury. 1538 male army recruits were randomly allocated to stretch or control groups. During the ensuing 12 wk of training, both groups performed active warm-up exercises before physical training sessions. In addition, the stretch group performed one 20-s static stretch under supervision for each of six major leg muscle groups during every warm-up. The control group did not stretch. 333 lower-limb injuries were recorded during the training period, including 214 soft-tissue injuries. There were 158 injuries in the stretch group and 175 in the control group. There was no significant effect of preexercise stretching on all-injuries risk (hazard ratio [HR] = 0.95, 95% CI 0.77–1.18), soft-tissue injury risk (HR = 0.83, 95% CI 0.63–1.09), or bone injury risk (HR = 1.22, 95% CI 0.86–1.76). Fitness (20-m progressive shuttle run test score), age, and enlistment date all significantly predicted injury risk (P < 0.01 for each), but height, weight, and body mass index did not. A typical muscle stretching protocol performed during preexercise warm-ups does not produce clinically meaningful reductions in risk of exercise-related injury in army recruits. Fitness may be an important, modifiable risk factor.