The importance of stretching derives from its ability to reduce the risk of injury from exercise and also from its role in increasing both flexibility and overall athletic ability. Studies on stretching are not perfectly conclusive, but a preponderance of opinion suggests that careful and appropriate stretching before and after exercise will reduce the risk of long-term and short-term injury and also limit discomfort. Appropriate stretching over time can make the body more flexible which has a number of different physiological benefits having to do with balance and posture. Stretching is thought to have a positive impact on athletic performance generally as well, largely because of its ability to allow the body to move more smoothly and efficiently.
The reduced chance of injury is a key reason to stretch regularly. The importance of stretching in preventing injury is largely a product of the need to allow joints and muscles to move through their full natural range of motion during exercise. If muscles are too tight joints will not move gracefully, and bones, muscles, and tendons will experience extra stress from exercise as they move through a limited and inefficient series of positions. Muscles that have been stretched are looser and allow the body to move smoothly and efficiently.
Flexibility can be improved with gentle but regular stretching. Careful stretching will gradually increase the range of motion available to muscles. The importance of stretching stems from the need to maintain good posture. Overly tense muscles will lead to improper posture which causes long-term damage both during exercise and when the body is at rest, as it will tend to rest in an unhealthy position. Loose muscles allow the body to relax into a more natural and healthy posture.
Athletic performance may be enhanced by careful stretching. Loose muscles move more smoothly and move through their full ranges of motion. Muscles that move in this fashion are able to propel the body more efficiently than muscles that are restricted to a limited range due to stiffness. The importance of stretching for improved athletic performance is not uniform across all areas of athletic endeavor, but most athletes can benefit from some form of stretching.
The importance of stretching carefully cannot be overstated. Forceful stretches, in which a great deal of pressure is suddenly applied, should be avoided, as they can cause tissue damage. Stretches should be smooth and should not proceed past the point of mild discomfort. Flexibility cannot be improved rapidly and attempts to do so often do more harm than good.