Touching one’s toes or moving the head in a circle feels positively blissful to most healthy adults. But the benefits of stretching are much argued in the halls of kinesiology departments and fitness centers across the country. One professor of sports medicine at the University of Virginia, Jay Hertel, explains the upside of a full range of motion and why sometimes feeling good is enough reason to get those shoulders rolling.

The Science of Stretching
“Stretching is really moving the joint in an effort to lengthen the muscle,” explains Dr. Hertel. That act should maximize the joint’s range of motion, which is a good thing.

“From a performance standpoint, the greater range of motion you have, the more likely you’ll be able to generate more force, which may make you run faster or jump higher. In addition to that, from an injury-prevention standpoint, in theory you’ll also be better able to react in real-life situations, like when you’re about to fall or need to jump over something,” he adds.

Sometimes stretching is painful. “That stretched muscle is sending a message to your brain that it feels good, but also that it hurts,” Dr. Hertel says. “The pain is important because it protects you from stretching too far and literally pulling the tissues apart.”

Over time, a person can increase tolerance to that pain, eventually becoming more limber and flexible.

The Injury Factor
Most studies looking into the benefits or risks of stretching have focused on team sports, which offer researchers large study sets. There is no clear evidence that stretching decreases or increases injury in athletes, says Dr. Hertel, who runs the Exercise and Sport Injury Lab at the University of Virginia. There have been studies that show having too little or too much flexibility are both associated with injury, which lead sports medicine experts like Dr. Hertel to conclude that “there is an envelope of acceptable flexibility in the middle.”

Because individual stretches are so person-specific, there is no definitive data as to which exercises are best for which body types or workouts.

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