Likely, you’ll fit into one of two exercise camps. Either you hate abdominal work, but you do it because it is a necessary evil, or you thoroughly enjoy it. Either way, most people want to have better abs. Adding a few more sets of sit-ups is not usually the answer for producing those washboard six-packs or tightening your midriff. Don’t let excuses like “poor genetics” or a “slow metabolism” control your fitness outcome, because these excuses are usually self-fulfilling prophecies. The solution is relatively straightforward, but it is not simple. One of the “secrets” for improving abdominal shape is to increase your metabolic rate, both acutely (for a short time) and chronically (throughout the day). Usually, your metabolic rate will be elevated for several hours after a workout, so it’s important to maintain regular workouts for your metabolic success.
Cardio for at least 20-30 minutes a day will go a long way toward increasing your metabolic rate both during and after training. Cardio uses the stored fat calories as energy sources to eventually reveal a flat abdomen. However, your long-term success is improved if your lean body tissue is increased because larger muscles burn more calories throughout the day than small muscles, even if you’re only sitting at your computer and working from home. By no means do you have to add 20 pounds of muscle before your resting metabolic rate increases; even a little more muscle helps, regardless of your age. You should choose abdominal exercises that shorten and tighten the fibers in this area and not exercises that excessively stretch the abdomen. Crunches on an exercise ball are great because they optimize your abdominal contractions, while protecting your back.
Muscle Form and Function
The rectus abdominis muscle is really a series of short fibers stacked vertically on each other. The linea alba is a thin tendon-like vertical line that creates a groove in the middle of the abdominal wall so the rectus abdominis appears to have a left and right half to it. Usually, there are three additional rows of horizontally placed tendons running across the rectus abdominis. The fibers of the rectus abdominis are short and only run from one horizontal tendinous insertion to the next. When the rectus abdominis is tensed, these short fibers bulge between the tendinous grooves, almost like small ropes or blocks, giving that six-pack look. However, even if you are not interested in a six-pack, the small blocks of abdominal fibers will give your waist that tight and flat look from your rib cage to your pelvis.
If both right and left halves of the rectus abdominis muscle contract together, the trunk is flexed forward so the head and chest move closer to the hips and legs (assuming a fixed pelvis). This is the general movement of the crunch. Although there is muscle activity in all the blocks during most abdominal exercises, the upper two rows preferentially contract and shorten the most when doing crunches. However, in the crunch on the ball, the inferior fibers close to the pelvis can be effectively activated.
You can see the external oblique muscles dance and tighten, if your midriff is reasonably tight, and especially if you twist to either side. If this is not the case yet, then crunches on the ball will move you a little closer to this goal. The external oblique runs from the lower ribs by small bundles of muscle fibers that are angled in the same direction that your fingers would point, if you were to put your hands in your pockets. As the external oblique approaches the center of your abdomen, it unites with other slips of muscle fibers to form a flat fan-shaped muscle that attaches to the iliac bones of the pelvis and hip structure and also the linea alba. When both left and rights sides of the external oblique muscles work together, they can act to flex the trunk and move the head toward the feet. When one side contracts (unilateral contraction), the body twists to that side.
The internal oblique muscle sits just deep to the external oblique muscle. It attaches on a thick connective tissue sheath in the lower back, called the thoracolumbar fascia, and from the iliac bone of the hip. Its fibers run around the side of the trunk at right angles to the external oblique muscle, fanning out from their origins and running toward the head (superiorly). It attaches on the lowest three or four ribs, where it becomes continuous with the internal intercostal muscles (respiratory muscles of the rib cage). Similar to the external oblique muscle, if both left and right portions contract together, the internal oblique flexes the trunk at the waist and moves the head towards the feet. It assists in twisting the torso if it contracts unilaterally.
Crunch on an Exercise Ball
This exercise will most effectively contract the upper two rows of the rectus abdominis, but the internal and external oblique muscles will also assist in the flexion of the trunk.
1. Carefully lie back on a Swiss ball. Start by placing the ball behind you and holding it with your hands. Bend your knees and lower yourself so your shoulders and back are lying along the center of the ball. Next, extend your knees and let the ball roll a bit toward your head. Continue until your knees are at about 90 degrees and the ball is lying in the small of your back (lumbar). Your shoulders will not touch the ball, but your shoulder blades will contact the ball in the starting position. Make sure your shoes have a good gripping surface; otherwise, you may risk sliding off the ball.
2. Place your hands so that your fingertips are on either side of your head. It’s not a good idea to place your hands behind your head and interlace the fingers. This is because as you fatigue, you could pull up on your head with your hands and forcefully bend your neck forward. This has the potential to hurt your neck. Instead, with your fingers placed on the side of your head (the temple area), you cannot use your head as a lever to help you lift your head and torso off of the ball.
3. Point your elbows to the side and away from your body (not forward). Take a breath; then exhale as you bring your head and chest upward toward the ceiling. Your shoulders should rise an inch or two during this first phase; you’ll feel your lower back press deeper into the Swiss ball and the upper row of rectus abdomnis contract strongly as you come up. Do not let the ball roll forward as you come upward. And don’t let your hips drop down as your chest comes upward.
4. During the second phase, try to come up even further so your shoulder blades (scapula) lift off of the ball. But, think about curling your shoulders and upper back so your chin moves toward your chest as your upper body is curling (or crunching) toward your thighs. Hold the crunched position for a count of two.
5. During the third part of the exercise, tilt your pelvis forward and upward toward your head as your shoulders move upward. A pelvis tilt is critical because it strongly activates the lower blocks of your abdominals. All the while, try to keep squeezing your abdominals while you’re holding the pelvis tilt.
6. Inhale as you slowly control your upper body as it returns to the starting position. The ball prevents your shoulders and head from resting between repetitions so you’ll maintain tension throughout the entire exercise and between repetitions. This greatly increases the effectiveness and intensity of the exercise.
Getting on and off the ball can be difficult or uncomfortable if you have previously hurt your lower back. Consult your sports medicine doctor before doing this or other abdominal exercises. However, this is considered an excellent exercise even for someone with a weak back, because it does not put your lower back at risk if done correctly. Also, the ball supports your lower back throughout the exercise, whereas regular sit-ups and leg lifts jeopardize even a healthy back. Furthermore, strengthening the abdominals reduces the risk for other back injuries.
Don’t hold your breath during the crunch on the exercise ball, since this increases intra-abdominal pressure and prevents the abdominal fibers from shortening as much (although it might feel easier to do the crunch when holding your breath). It is good to either exhale as you are crunching forward, or even better, exhale before you do the contraction. Then concentrate on achieving a maximal shortening of the fibers during the exercise.
It would be impossible to attain fitness, aesthetic or sport objectives and tight abdominals if your diet is mainly high in fats and calories. Even if your diet is pretty good, you may need to add cardio to help meet your training goals. If your bodyweight goes down, crunches will become easier because you have less to lift each time you rise from the ball. Therefore, you’ll need to add a few more repetitions to continue progressing. You can also add a slight twist to the right as you elevate your shoulder blades from the ball, followed by a slight twist to the left on the next repetition. The twists increase the activation of the oblique muscles and this tightens the “love handle” region of your waist.
Probably nothing worthwhile or lasting comes easily, and this is certainly true for the abdominals. As a result, you must carefully set high standards and realistic goals for your diet and exercise program and you must establish firm deadlines for achieving success. Then, you must move your dream forward with determination; let nothing stop you from meeting those goals. So, maybe not all abdominal exercises are fun to do, but this exercise is not exhausting, yet it’s effective and intensive.
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