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Proper Performance of Ab Exercises

by Gary F. Zeolla

Most everyone desires a flat stomach or even the coveted abdominal "six-pack." And to this end, a wide variety of ab exercises have been devised. However, ab exercises are frequently improperly performed. But, as with any strength training exercise, to get the full benefit the exercise must be done correctly. But before getting to the actual exercise descriptions, a few general points need to be discussed.

General Points

The Myth of Spot-Reducing:
Performing ab exercises will not help a person lose fat around the waist. It simply is not possible to "spot-reduce." However, as body fat is lost through other methods, the underlying ab muscles will begin to show. So to attain that coveted "six-pack" requires both weight loss techniques and exercises to strengthen the ab muscles.

Number of Reps and Sets:
It is very common to see people doing 50-100 reps of ab exercises. However, performing that many reps makes the exercise more of an aerobics exercise than a true strength training movement. So it is best to keep ab work in the 8-15 rep range.

Beginners should start with one set of each exercise. But after a couple of weeks, a second set should be added.

For all exercises, initially no resistance should be used. Once one is able to do 15 reps on the first set, stay with 15 reps with no resistance for that set until 15 reps can be performed on the second set as well. Once one is able to do 2 sets of 15 reps, then add resistance.

The same pattern should hold thereafter. With a given resistance, work up to 15 reps on the first set then on both sets, then increase the resistance again.

For exercises where it is not possible to add resistance, once two sets of 15 reps is reached, work up to 20 reps on the first set, then 20 reps on both sets. Follow the same pattern for additional reps, adding five reps to the first set and then to both sets.

Muscles and Actions Involved:
The term "ab muscles" actually refers to several different muscles. These include the rectus abdominis (on the front of the torso) and the external obliques (on each side of the torso).

The rectus abdominis ("abs") are involved in two basic motions. The upper abs are involved in pulling the chest towards the hips; the lower abs are involved in pulling the hips towards the chest. The obliques are involved in twisting the torso and bending to the side.

To fully work the abs, it is important to incorporate exercises that work the abs and obliques in all of these directions. So it is recommended that the trainee perform at least one ab exercise where the chest is moved towards the hips (for the upper abs), one where the hips are moved towards the chest (for the lower abs), and one twisting motion or a side bend type of motion (for the obliques). Some ab exercises combine more than one of these motions and thus are very effective and time saving movements.

However, it is important to note that the range of motion of the rectus abdominis is very limited. When bending the upper body forward the abs are only used in the first few inches. Anything beyond this involves the hip flexors more than the abs. It is for this reason that a full sit-up is actually more of a hip flexor movement than an ab exercise.

Similarly, when raising the legs towards the head, the abs are only involved in the latter half of the movement, when the thighs are perpendicular to the body and afterwards. The hip flexors are primarily involved in raising the legs from straight with the body to a position perpendicular to the body.

These points are important to remember when performing ab exercises.

Changing Exercises:
As with any strength training exercise or routine, the body will eventually become adapted to it and progress will halt. So it is important to change routines periodically. For the abs, simply substitute different ab exercises about every three months or so. But maintain the same pattern of including exercises for the upper abs, the lower abs, and the obliques in each new routine.

The abdominal and oblique muscles are very important in stabilizing the trunk of the body when performing squats and deadlifts. And they get quite a bit of work when doing these lifts, especially if they're done without a belt or power suit. However, some direct ab and oblique work would be prudent for the powerlifter as well.

Proper Performance of Exercises

Crunches are probably the most basic exercise there is for the abdominal muscles. They primarily work the rectus abdominis and secondarily the obliques.

That said, to perform crunches, lie flat on the floor or other flat surface. It helps to use some kind of padding, such as an exercise mat, if one is lying on a hard floor. Bend the knees and bring the feet towards the hips forming about a 45-degree bend. The feet should remain flat on the floor throughout the movement. The feet should be about shoulder width apart.

Some recommend locking the fingers behind the head. However, when this is done, there is a tendency to pull up with the arms. Such an action should be avoided. So to prevent his, it would be better to place the hands on the sides of the head.

Keeping the lower back on the floor and the head in a neutral position, slowly raise the shoulders off of the ground. Do not bend the head towards the chest. The head should remain in a straight line with the body. As the shoulders are raised, the pelvis should flatten so that there is no arch in the back. The entire movement is only of a few inches. Going up any higher would involve the hip flexor muscles. Exhale as the shoulders are raised.

Lower the shoulders back to the ground in a slow, controlled manner. Inhale during the downward movement.

To add resistance, weight plates can be held on the chest. This will, of course, necessitate moving the hands to the chest to hold the weights. But be very careful when using weights and be sure to not come up farther than as described or undo stress will be placed on the lower back.

Twisting Crunches:
A basic variation of the crunch is to do them in a twisting fashion. Twisting increases the involvement of the obliques. The same instructions apply, except rather than coming straight up, the lifter twists to one side so that the head and shoulders are curling outside of the knee. Slowly lower back down, and then curl up again, twisting to the other side.

Leg Raises/ Reverse Crunches:
The common name for this kind of exercise is "leg raises." However, a better name is "reverse crunches" to emphasize the limited range of motion through which the legs should be moved.

How this exercise is generally done is for the trainee to lie on the floor with the legs straight, and then to raise the straight legs to a position perpendicular to the body, and then to return to the starting position. However, this is exactly the opposite way in which this exercise should be done.

As indicated above, the hip flexors are primarily involved in raising the legs from straight with the body to perpendicular. So by performing leg raises in the "traditional" manner, the abs are actually getting very little work.

To properly perform reverse crunches, lie flat on the floor, preferably on some kind of padding. Bend and raise the legs so that the thighs are perpendicular to the body and the lower legs are parallel to the body. This is the starting position.

Next, slowly bring the thighs as far forward as possible, consciously pulling with the ab muscles. The end position should have the knees as close to the face as possible. Pause, and then slowly lower the thighs to the starting position. Pause, and then start the second rep. Be sure to avoid any kind of rebounding, swinging, or rocking motion. The ab muscles not momentum should be used to bring the thighs forwards and back.

Inhale at the start of the movement. Then exhale as the thighs are bought forward and inhale as they are lowered.

To add resistance, reverse crunches can be done on a slant board. The greater the angle of the board, the harder the exercise will be. So start with as low an angle as the board set-up allows. Once 15 reps can be performed with good form, then gradually increase the angle. Hold onto the sides of the board above the head to prevent slipping down the board.

Twisting Reverse Crunches:
As with crunches, reverse crunches can be performed in a twisting fashion. Again, the same instructions apply, except, the thighs should be brought forward at an angle so that the knees angle to a point outside of the shoulders.

Bring the thighs as far forwards as possible to one side; pause, and then return to the starting position. Pause again, and then bring the thighs forward to the opposite side.

Crunch/ Reverse Crunch Combo:
This exercise is a combination of crunches and modified reverse crunches. This way, both the upper and lower abs get worked at the same time. For the reverse crunch part, bend your legs place your feet flat on the floor. With the arms crossed across the chest, crunch up as usual and raise your thighs at the same time until your elbows touch your thighs. For a video,  click here.

Bicycle Ab Exercise:
This exercise is a combination of twisting crunches and reverse crunches. The starting position is the same as for reverse crunches, i.e. lying on the floor with the legs raised and bent with the thighs perpendicular to the body and the lower legs parallel to the body. The hands should be held at the sides of the head as for crunches, with the elbows forward.

But unlike reverse crunches, only one thigh is brought forward at a time. Bring the left thigh forward, and at the same time do a twisting crunch towards the left side. The right elbow should come across the body and touch the left kneecap. Pause, then return to the starting poison.

Next, bring the right thigh forward, and at the same time do a twisting crunch towards the right side, touching left elbow to right kneecap. Pause, then return to the starting poison. This is called the "bicycle ab exercise" as the legs move as if peddling a bicycle.

Exhale as the leg and elbow are both raised, and inhale as they are lowered.

This is a very grueling but effective exercise. By combining three different movements (bringing the hips towards the chest, the chest towards the hips, and a twisting motion), it effectively works the lower abs, the upper abs, and the obliques all at once.

Unfortunately, there really is no way to add resistance to this exercise. But with as grueling as it is, it will take some time for most to be able to perform two sets of 15 reps. For a video of this exercise, click here.

Hanging/ Captain's Chair Leg Raises:
This is simply a more advanced form of reverse crunches. As indicted above, when performing reverse crunches on a slant board, the greater the angle of board the greater the resistance. And the greatest angle of all would be to be in a full vertical position. But to perform the exercise in this position requires that the legs be hanging freely in some manner.

The most obvious way to do so would be to hang from a chin-up bar, holding onto the bar with the hands. But doing so can put strain on the shoulders and arms and requires a strong grip. If is for these reasons, that the "captain's chair" was invented.

A captain's chair is usually a combined station that one can also perform dips on. It should have elevated parallel bars with padding on them. The trainee places his/ her forearms on the pads, which support the weight of the upper body while allowing the legs to hang freely below.

But whether done hanging form a chin-up bar or using a captain's chair, the basic movement is the same. But unfortunately, this again, is a very commonly mis-performed exercise.

Most will start with their legs hanging straight down, and keeping them straight, raise them to perpendicular with the body, and then lower them. But again, this range of motion involves primarily the hips flexors with little ab involvement. And to make matters worse, many will begin "swinging" their legs so that momentum is doing most of the work. DO NOT DO THEM LIKE THIS!

The instructions for properly performing handing leg raises is basically the same as for reverse crunches. Bend the legs and raise them so that the thighs are just above perpendicular to the body and the lower legs parallel to the body. The hip flexors will be involved in this initial movement, but it is the only time they will be involved as this is the starting position.

Now raise the knees up by curling the body and pulling with the abs, bringing the knees as close to the face as possible. Pause, and lower the thighs back down to just above perpendicular to the body. Pause, and then perform the second rep.

Exhale as the thighs are raised and inhale as they are lowered.

Unfortunately, again, there really is no way to add resistance to this exercise. But again, with as grueling as it is, it will take some time for most to be able to perform two sets of 15 reps.

Twisting Hanging/ Captain's Chair Leg Raises:
Due to the hanging effect, the obliques are used quite a bit in hanging/ captain's chair leg raises. But doing this exercise in a twisting fashion works the obliques even more. To do so, raise the knees as high as possible to one side, going past the torso to the side; pause, and then return to the starting position. Pause, and then raise the knees to the opposite side.

This is a very difficult exercise, so it should only be attempted by more advanced lifters.

Swiss Ball Crunches:
A Swiss ball is a large ball, usually larger than a beach ball, but made of very strong material. It is strong enough that exercises can be performed lying on the top of it. And doing crunches on a Swiss ball greatly increase the effectiveness of the movement. It forces the abs to work harder and brings in the obliques in order to stabilize the trainee on the ball.

To do them, sit on the ball with your buttocks a little forward from the highest part of the ball. Keep you feet flat on the ground, with your legs spread about shoulder width to balance yourself.

Then lie back on the ball so that you are slightly hyperextended, i.e. so that your upper back is a little bit below parallel with your buttocks. Pause, then bend forward as you would for a regular crunch, coming up only a few inches. Pause, and then return to the starting position. Be sure to concentrate the whole time so that you don't fall of the ball!

It is possible to increase the resistance by holding weights on the chest as for regular crunches. However, doing so is a little tricky. So only do so if you are confident in your ability to maintain your balance on the ball. It would also help if you have someone hand the weights to you after you are in position on the ball.

Side Bends:
Side bends are a very good exercise for working the obliques. Stand erect, feet shoulder width apart, holding a dumbbell in one hand. Then bend sideways towards the side holding the dumbbell. Keep you legs straight, bending only at the side of the waist. Bend as far to the side as your flexibility allows. Pause, then return to the erect position and then a little bit towards the other side. Then return to the fully erect position. That is one rep. Repeat for the required number of reps on that side. Move the dumbbell to the other hand and then repeat the sequence for that side.

If one side is weaker than the other side, then work the weaker side first. Also, do not do more reps or use more weight for the stronger side than you do for the weaker side. Doing so would only increase the muscular imbalance.

Do not hold dumbbells in both hands while performing this exercise. By doing so, the weights would counter-balance each other and no effective resistance would be added.

Various Nautilus and other brands of machines have been devised to work the abs. The advantage of these machines is resistance can easily be added. But, as with any machine, they reduce the recruitment of stabilizing muscles, and thus are less effective than free weight exercises.

The best kind of machine is one that involves moving both the chest towards the thighs and the thighs towards the chest thus working both the upper and lower abs.

When using a machine, between reps, lower the weight stack so that it just "taps" the remaining weights but does not come to a complete stop. In this way, constant tension is maintained on the abs. Also, starting the stack from a stopped position is the hardest part of the exercise and can place undo strain on the lower back when done repeatedly.

Broomstick Twists:
This is an exercise that is often done, but it is not very effective. Simply twisting from side to side while standing or sitting does not provide sufficient resistance for muscular development. And holding something heavier than a broomstick, like a barbell, doesn't help either. No resistance is effectively added in the twisting direction. Any of the above twisting variations of exercises would be better ways to work the obliques.

There is a Nautilus "Rotary Torso" machine that does effectively add resistance in the twisting direction. I have only been in one gym that had such machine. But if you have access to such a machine it would be a worthwhile way to work the obliques.

See also Abs Exercises Videos and under "Ab Exercises" at Squat Assistance Exercises.

The links below are direct links to where the books can be purchased from Books-a-Million.

Bell, James T. and Karl M. Dauphinais. The Book on Personal Training. Tampa, FL: International Fitness Professional Association, 2001.
Delavier, Frederic. Strength Training Anatomy. Paris, France: Human kinetics, 2001.
Hatfield, Frederick, C. Bodybuilding: A Scientific Approach. Chicago, IL: Contemporary Books, 1984.
Schuller, Lou. The Testosterone Advantage Plan. USA: Rodale, 2002.

Proper Performance of Ab Exercises. Copyright 2003 by Gary F. Zeolla.

The above article was posted on this site on October 11, 2003.

Powerlifting and Strength Training
Powerlifting and Strength Training: Proper Performance of Exercises

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