The role of stretching on performance and injury prevention
Stretching before sports participation is commonly practiced, however, it’s effect on performance and injury are not well understood. The focus of this article will be on pre-participation stretching, rather than habitual stretching. The purpose of muscle stretching before an event is to: (1) make sure the athlete has adequate flexibility in their joints to optimally perform the sporting activity and (2) to increase muscle compliance or decrease muscular stiffness, thus reducing the risk of injury.
Research has shown that administering a set of stretches will decrease the ability to generate maximal muscular force. This is known as the “stretch-induced strength loss”. This loss of strength depends on the type of contraction, muscle length, and stretching technique applied. There is no loss of strength with dynamic stretching and with respect to muscle length, stretch-induced strength loss is not apparent at greater lengths. In regard to contraction type, losses of strength have not been shown to occur with concentric contractions (muscle shortening). These effects, however, are less apparent with tests of muscular-power and are diminished when stretching is combined with other activities generally used in a warm-up.
Pre-performance stretching may impact on certain injury types but not on others (i.e. overuse injuries). There are good grounds for why stretching may influence the chance of sustaining a muscle strain injury. It is proposed that stretching causes the muscle-tendon unit to be more compliant, therefore allowing larger force production at longer muscle lengths. As a result, the enhanced ability to prevent excessive muscle lengthening may reduce the susceptibility to a muscle strain injury.
Flexibility training must be of sufficient duration, intensity and frequency to decrease passive resistance to stretch. The stretching prescription for injury prevention should follow the recommendations outlined below. Pre-participation stretching should target muscles groups known to be at risk for a particular sport. Stretching should be applied 4-5 times to pain tolerance to the target muscle groups for 60 seconds and performed bilaterally. Finally, some dynamic pre-participation activities should be performed before actual performance to avoid any stretch induced strength loss.
McHugh, M. P., & Cosgrave, C. H. (2010). To stretch or not to stretch: the role of stretching in injury prevention and performance. Scandinavian journal of medicine & science in sports, 20(2), 169-181.
B.Sc. (Sport Sc, ExHealth); B.Sc. (Hons – ExRehab)