Here’s how to blast calories and boost your mood in joint-friendly ways: Go low impact To burn fat without jarring joints, choose cardio that keeps one foot on the ground at all times, like walking. For severe pain, try swimming or water aerobics, since the water eliminates impact and helps soothe joints. Cycling is another excellent option that can burn about 500 calories an hour. Opt for a recumbent bicycle if you have a sore back. MORE: 2 Supplements That Help Noisy Knees Stay straight and steady Any activity with turns, pivots, or stops and starts (like tennis) can be uncomfortable because the joints absorb shock. In winter, try cross-country skiing or snowshoeing to burn as many calories as jogging—without stress. Indoors, the elliptical machine moves your body through a safe range of motion with minimal impact. Strengthen your joints Toning the muscles that surround your knees, hips, and back can reduce pain by improving your posture, alignment, and overall joint mobility. Follow these tips for stronger, pain-free joints. Chris Freytag is a board member of the American Council on Exercise, the star of many Prevention fitness DVDs, and author of Prevention’s Shortcuts to Big Weight Loss.