Does stretching prevent injury? [news]

While it seems common sense to warm up muscles, and it often feels good, too, is there any evidence that stretching reduces muscle soreness or prevents injury? The practice of stretching gained popularity in the 1960s when scientists believed muscle soreness resulted from muscle spasms. Lengthening a muscle was thought to restore blood flow and reduce the spasm. While this theory of muscle soreness has been disproved, the practice of stretching continues. Physiologists now believe muscle soreness is the result of minor damage to the smallest contracting units of the muscle, called sarcomeres, during intense exercise. Tiny tears can form in these cells when a muscle, or group of muscles, are unaccustomed to a hard workout. The micro-damage is accentuated when performing exercises that require muscles to contract at the same time as they are forced to lengthen and stretch, such as running down hill.