Bob Harper

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You're Working Your Arm Joints, Not Your Arm Muscles
When you lock your arms during push-ups, you not only put unnecessary stress on your elbow and shoulder joints, but you also take some of the load off your muscles, giving them a chance to rest. In this video, celebrity trainer Joel Harper shows you how to do a proper push-up that will keep your biceps, triceps and chest muscles pumping and burning (that's a good thing, trust us).

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