From the New York Times: Stretching: The Truth.

When Duane Knudson, a professor of kinesiology at California State University, Chico, looks around campus at athletes warming up before practice, he sees one dangerous mistake after another. "They’re stretching, touching their toes. . . . " He sighs. "It’s discouraging."

If you’re like most of us, you were taught the importance of warm-up exercises back in grade school, and you’ve likely continued with pretty much the same routine ever since. Science, however, has moved on. Researchers now believe that some of the more entrenched elements of many athletes’ warm-up regimens are not only a waste of time but actually bad for you. The old presumption that holding a stretch for 20 to 30 seconds — known as static stretching — primes muscles for a workout is dead wrong. It actually weakens them. In a recent study[continue].