According to the American Council on Exercise, the bicycle provides the best toning of all abdominal activities. To execute a bicycle, lie on your back, tighten your navel and place your hands behind your head. Your fingers should only support your head, not pull on it. Contract your stomach muscles as much as possible, then raise your head and shoulder blades off the ground. Keep one leg straight and bring the other knee toward your chest. Rotate your torso so that the opposite elbow reaches toward the lifted knee, then alternate back and forth in a cycling motion. Repeat several times until you feel your muscles working, being careful not to push your stomach out. Make sure you control the movement, holding the pose each time for a second or two before alternating. This exercise works the upper, as well as the lower and oblique, abdominal muscles.
Find a sturdy chair and sit on the edge of it with your feet touching the floor. Grasp the chair with both hands at hip level, then draw your knees to your chest while breathing out without arching your back. Hold the pose for two seconds, exhale, release and repeat. Remember that, as you are working your abdominal muscles, your neck and shoulders can relax. Continue the repetitions only as long as you can keep your inward contraction, but stop if this exercise causes pain in your wrists when you push down.
To do a corkscrew, lay on your back with your arms at your sides and raise your feet in the air with your soles facing the ceiling. Using only your abdominal muscles, lift your hips off the ground so that your feet rise up. Try not to allow them to rise over your head or you will be working stomach muscles. Make sure to maintain the scoop of your belly rather than pushing the muscles out with each lift. Keep your legs straight, as controlling your movements ensures that you do not strain your hips or back. According to Sports Fitness Adviser, this exercise promotes a strong core, which benefits balance and stability.
The effectiveness of regular crunches increases when small adjustments are made to augment their intensity. Regular crunches work just your upper abdominal wall, while the advanced version incorporates your lower abdominal muscles and increases intensity. For advanced crunches, lie on the floor with your knees bent at a 90-degree angle. With your hands gently supporting your head, slowly crunch toward your knees. Remember not to pull on your head. Lower your upper body to just above your shoulder blades to maintain the contraction. Do eight to 12 repetitions, stopping if your back or neck hurt or you can no longer maintain the contraction in your abdominal muscles.