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No matter the sport, athletes often limber up their muscles with a pre-game stretch, and runners are no exception. A good stretch has long been considered key to preventing injury.
But as NPR's Allison Aubrey reports, there's a whole new thinking about how best to stretch and when.
ALLISON AUBREY: Dan Pereles is not only an orthopedic surgeon who treats lots of injured runners, he's also a runner himself. And for most of his career, he practiced and preached the value of the pre-run stretch.
But a few years ago, he started to notice that committed stretchers weren't necessarily preventing injuries - at least with the type of stretching they were doing. He was curious to know if there was something to his observations, so he designed a study with 3,000 runners to evaluate the effectiveness of stretching.
Dr. DAN PERELES (Orthopedic Surgeon): The question is will a static stretch -meaning standing in one place, stretching your quadriceps, stretching your hamstrings, stretching your calf muscles - before running, which is typically what runners do - that's the tried and true classic way of stretching - is that helpful? Does that prevent injuries? That was the question we asked.
AUBREY: Pereles says, in theory, the answer should be yes. When you stretch, you start moving blood to the muscles, and this could make people feel better. Plus, studies have shown that when you lengthen muscle fiber just a little bit, its force is increased.
Dr. PERELES: So, intuitively, we think, gee-whiz, if we can stretch this, then we'll have better force, we'll have more endurance, and we'll have less injury.
AUBREY: But Pereles says this is not at all what he found. His runners were divided into two groups. One group did traditional stretches for three to five minutes before each run, and the other group did not stretch at all. Both had a mix of men and women running at different speeds and distances. And at the end of three months, Pereles found that the stretchers faired no better than the non-stretchers.
Dr. PERELES: I was surprised, actually, that the stretching didn't prevent injury. I thought there would be a mild effect, and I thought that folks would see maybe a 10 or 20 percent benefit, but that's just the way it was. There was absolutely no benefit.
AUBREY: This is not the first study to question the value of pre-run static stretching, and those who have been paying close attention say they're not surprised.
Pete Sherry is the head cross-country coach at Herndon High School in Virginia and a former elite runner himself. He now practices and teaches a completely different kind of stretching.
Mr. PETE SHERRY (Head Cross-Country Coach, Herndon High School): We don't do any static stretching. In fact, I don't allow any static stretching on my team at any point during the season. It's what we say not approved.
AUBREY: Instead, Sherry teaches all of his runners a form of dynamic stretching that emphasizes gentle fluid repetitions. He calls it active-isolated stretching.
Mr. SHERRY: The best way to look at it is probably flexibility exercises.
AUBREY: As Sherry sits down on the running track to demonstrate, he shows me why he thinks static stretching is the wrong way to go.
Mr. SHERRY: So what I'm doing here is I'm going to start with the lower hamstring.
AUBREY: As he gets into position, he says think about the traditional move many of us learned in high school, such as bend-and-hold toe touches. This is the kind of static or still stretch that's supposed to loosen the hamstrings. But as Sherry tries one, he tells me to watch what happens. When he leans forward, it's not his thigh that's stretching. It's his back that's being pulled awkwardly.
Mr. SHERRY: If your back is tight or your calf is tight, the hamstring could be neglected. We're really not getting to it.
AUBREY: Sherry says there's a much better way to isolate and limber up the hamstrings.
As he lies on his back, he moves his leg up towards his chin in a fluid motion and holds it for just a few seconds.
Mr. SHERRY: Now, we do it again, and each time I get a little deeper stretch, I can feel the muscles stretching, and I'm bringing my knee toward my chin to allow a little deeper stretch.
AUBREY: This method may take a little longer, but Sherry says it's not forcing the stretch or overextending his joints.
A few years ago, Sherry says he was one of the only coaches in the area teaching this method. But now when he takes his runners to competitions, he sees more and more teams trying it.
Allison Aubrey, NPR News.
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