Finding a study that supports your opinion on stretching is like holding a gun to a guy’s head and then asking him what he thinks about you—you’re gonna hear what you want to hear.

Since experience is the best teacher, we let Keith Scott, C.S.C.S., a strength coach and rehabilitation expert in Medford, N.J., with more than 17 years of in-the-trenches coaching experience, give us his final word on the art of loosening up.

How should I stretch?
Get into any position in which you feel the burn in the muscle, and hold it. “Twenty-second holds are the best length of time,” says Scott. “This will ensure that the tissue being stretched will elongate over the long term.” As you improve (the stretch doesn’t feel as intense), increase the stretch. But you don’t need to hold it for any longer than 20 seconds.

When should I stretch?
Stretching before a big lift can increase your range of motion immediately, allowing you to get more out of the exercise. However, holding the stretch for too long or repeating it too many times can defeat the purpose, temporarily weakening the muscle—a major point anti-stretching advocates always make.

That’s why most experts suggest that, before lifting, you limit your stretches to just 10 seconds and repeat only once. Afterward, perform some dynamic exercises for the same muscle group (such as lunges for the hamstrings or arm swings for the shoulders). This will help you warm up for the lifting that follows. At other times of the day, you can hold stretches for 20 seconds as usual.

Stretch for strength.
“Stretching your ankles and hip flexors for 20 seconds before a heavy squat or deadlift will help you lift heavier,” says Scott. “Mobilizing the ankle joints allows you to sit deeper in the bottom of your squat or pull from the floor.” Stretching the hip flexors (the muscles above your thighs) will help prevent them from inhibiting the glutes—where your power comes from.

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