Lie on your back, knees bent and feet flat, arms by your sides, palms down. Keeping your buttocks and legs relaxed, inhale, then exhale and draw your deep abdominal muscles in toward your spine, bringing your right knee toward your chest [A]. Using your abs, slowly bring your left knee toward your chest, pressing your arms and hands into the floor [B]. Hold for a count of 10, then slowly release, one leg at a time, keeping abs drawn in. Repeat 4 more times, starting with your right leg.