Targets upper and lower abs and obliques Lie on your back with your hands at your sides, legs straight, and heels hovering about six inches off the floor (A). Start sitting up while elevating your left arm with the elbow bent so it resembles a sprinter's pumping motion. At the peak of the situp, bring your right knee to your chest (B). Return to start, keeping your legs raised, and repeat with the opposite arm and leg. That's one rep. Do up to 20. Perfect Form Control your movement through…
