Try It on One Leg. Once you've mastered doing an exercise with a narrow base of support, you're ready for the next challenge: balancing on a single leg. Instead of standing on both legs during some of the same moves above, try it on a single leg. Start by just lifting one heel (keeping your toes on the floor) while doing your upper body moves or working up to a single leg squat. As you get better, lift that foot off the ground completely. From there, you can play around with the position of your lifted leg—holding it behind you, in front of you, to the side or, for a greater challenge, moving that leg while you balance on the other leg and perform upper body movements. Just be sure to alternate legs to keep your strength and muscle tone balanced (no pun intended) between both sides of your body. Tip: You can also experiment with momentary one-leg balances. For example, on a forward lunge, lift your front or back leg for a moment each time your push up out of your lunge. Watch my 6-Minute Hips, Glues & Thighs Workout video for a few examples of this technique.