Stand up straight. Check out the stair-climbing section in any gym and you'll see at least a few people hunched over their machines, gripping the side rails for dear life or reading a book. This posture strains the shoulders even as it makes the exercise easier. To get the most from your climb time, stand up straight with your hands at your sides or resting lightly on the rails for balance only. If this posture is new to you, you almost certainly will have to lower your usual speed or resistance. But as David Harris, the national training director of Equinox Fitness Clubs, points out, "you will actually burn more calories, because your heart and the rest of your body now have to work harder."