Squatting when you need to reach something low is better for your back than bending over. It also helps build strength in your legs and hips, which stabilizes your joints. But it can be tough on your knees. To do it right, hold onto a countertop or sturdy piece of furniture and "sit" into a squat, lowering yourself as far as you can comfortably and pulling up with your arm and bottom muscles. Be sure to keep your knees aligned over your ankles. If this is too painful, lean down from a chair, not from standing, for less stress on your knees.