Abdominal fat also known as central obesity, occurs when excessive abdominal fat around the stomach and abdomen has built up to the extent that it is likely to have a negative impact on health. There is a strong correlation between central obesity and cardiovascular disease. Abdominal obesity is not confined only to the elderly and obese subjects. Abdominal obesity has been linked to Alzheimer’s disease as well as other metabolic and vascular diseases.

Visceral and central abdominal fat and waist circumference show a strong association with type 2 diabetes.

Visceral fat, also known as organ fat or intra-abdominal fat, is located inside the peritoneal cavity, packed in between internal organs and torso, as opposed to subcutaneous fat, which is found underneath the skin, and intramuscular fat, which is found interspersed in skeletal muscle. Visceral fat is composed of several adipose depots including mesenteric, epididymal white adipose tissue (EWAT) and perirenal fat. An excess of visceral fat is known as central obesity, the “pot belly” or “beer belly” effect, in which the abdomen protrudes excessively. This body type is also known as “apple shaped”, as opposed to “pear shaped”, in which fat is deposited on the hips and buttocks.

Abdominal muscles: A large group of muscles in the front of the abdomen that assists in the regular breathing movement and supports the muscles of the spine while lifting and keeping abdominal organs such as the intestines in place. Abdominal muscles play a key role in exercises such as “sit-ups.”

What You’ve Been Waiting For! The Exercises

Since this is a bodybuilding experiment, I used weight that was light enough to allow me to perform at least five repetitions. The mean number is on top and the peak number is on bottom.

Exercise	Lower Rectus Abdominis	Internal s	External Oblique	Lumbar Erector
Front Plank	22.4 33.5	31.2 42.6	21.7 26.7	2.8 5.8
RKC Plank	88.0 115.0	76.2 99.5	71.0 104.0	2.9 5.4
35 lb Plate Squat	7.8 19.8	21.0 67.9	7.0 21.1	65.5 137.7
Bodysaw	92.2 188.0	105.0 208.0	71.9 143.0	4.4 15.0
Side Plank	33.1 48.8	52.4 77.6	57.6 73.8	18.8 29.2
Ab Wheel from Knees	103.0 145.0	112.0 184.0	63.4 97.2	4.9 10.6
Ab Wheel from Feet	103.0 191.0	114.0 220.0	90.0 130.0	4.7 9.8
Lying Leg Throw	64.9 116.0	69.8 150.0	57.3 98.7	5.6 10.2
100 lb Suitcase Carry	13.2 31.2	21.4 33.2	46.7 85.5	65.6 107.0
Band Pallof Press	6.8 11.5	16.8 27.1	29.6 44.3	22.5 32.5
120 lb Pallof Press	9.9 15.0	9.2 15.7	25.0 34.8	10.9 29.3
90 lb Landmine	7.7 12.5	101.0 154.0	18.1 26.3	99.0 168.0
BW Tight Rotation	15.1 18.6	75.4 133.0	35.8 63.6	49.6 66.0
10 lb Tight Rotation	13.5 17.3	64.2 135.0	27.7 35.8	72.4 130.0
10 lb Overhead Tornado Twirl	12.9 25.8	58.0 104.0	29.7 52.0	85.4 160.0
120 lb Half-Kneeling Cable Chop	27.2 68.2	60.4 155.0	21.2 39.6	17.7 54.7
100 lb Half-Kneeling Cable Lift	6.0 8.8	83.4 144.0	16.2 36.7	103.0 248.0
10 lb Tornado Ball Slam	13.0 18.0	89.4 187.0	28.7 53.1	77.8 189.0
50 lb Turkish Get Up	31.0 133.0	37.9 138.0	38.5 191.0	40.7 139.0
BW Straight Leg Sit Up	78.2 122.0	28.2 45.7	57.7 89.6	1.7 3.1
BW Hanging Leg Raise	124.0 300.0	30.2 92.8	76.3 163.0	4.2 6.9
100 lb Crunch	55.3 83.2	28.8 45.2	40.7 80.5	9.5 23.0
50 lb Swiss Ball Crunch	102.0 231.0	22.8 55.6	47.1 95.8	4.0 11.0
100 lb Side Bend	35.1 80.1	15.6 33.2	69.9 108.0	41.0 60.8
BW Dragon Flag	56.1 102.0	27.8 59.0	28.7 71.4	7.3 46.7
200 lb Farmer’s Walk	13.2 34.0	8.9 19.5	5.9 15.6	24.8 41.2
Overhand Sledgehammer Swing	34.8 71.6	20.3 41.6	43.2 77.7	27.7 64.3
Rotational Sledgehammer Swing	12.2 46.8	17.7 60.2	14.7 29.6	28.7 52.1
BW Hand Walk Out	47.2 79.1	17.3 40.1	44.8 86.1	7.1 27.3
275 lb Parallel Squat	25.0 103.0	8.2 16.0	8.4 17.2	75.5 109.0
225 lb Front Squat	14.4 59.7	16.6 33.1	7.2 16.1	69.3 140.0
225 lb Good Morning	14.0 58.5	4.8 9.7	5.6 12.5	46.4 94.6
275 lb Zercher Squat	15.7 44.5	18.2 36.7	11.7 25.8	62.9 82.0
405 lb Deadlift	31.0 97.3	13.1 32.3	12.4 28.6	52.5 73.9
405 lb Hip Thrust	23.6 64.4	10.7 56.4	14.2 31.9	42.5 122.0
60 lb Lumbar Extension	16.0 38.9	7.4 16.7	23.1 33.9	81.4 172.0
10 lb Weighted Bird Dog	11.2 22.0	4.0 6.8	14.6 25.4	52.4 112.0
100 lb 45 Degree Hyper	25.7 81.5	9.9 41.9	3.8 10.8	60.0 132.0
100 lb Back Extension	28.4 84.3	18.8 49.9	5.7 10.4	63.7 139.0
185 lb Bulgarian Squat	27.7 74.8	6.2 8.8	8.3 17.5	60.2 107.0
90 lb Pendulum Quadruped Hip Extension	29.2 119.0	5.0 6.9	9.1 15.2	56.9 112.0
BW Chin Up	249.0 461.0	40.4 60.7	32.3 61.7	14.1 36.9
90 lb Chin Up	162.0 301.0	51.1 73.6	42.1 65.1	14.2 29.8
135 lb Barbell Curl	18.5 92.7	19.1 36.2	10.0 18.4	71.4 111.0
100 lb Cable Tricep Extension	70.2 148.0	32.5 62.8	34.1 71.7	8.3 13.6
100 lb Pullover	34.6 70.5	28.9 51.5	31.4 102.0	19.0 75.2
BW Push Up	7.1 20.3	8.9 13.8	16.4 24.2	3.4 10.9
275 lb Bench Press (with arch)	2.9 4.7	9.1 25.0	8.0 18.8	50.3 93.5
45 lb Barbell Push Sit Up	19.4 36.9	18.5 48.4	63.6 121.0	7.2 10.5
180 lb Reverse Hyper	3.5 11.1	9.4 38.2	6.5 11.5	98.6 141.0
BW Reverse Hyper	2.5 32.4	4.1 16.2	10.6 14.9	78.8 159.0
270 lb Reverse Hyper	7.2 27.5	13.9 53.6	13.0 33.2	95.2 150.0

Abdominal Fat; 10 minute Workout to Reduce Your Abdominal Fat

The Winners

Since I could only test four muscles at a time, I opted to go with the lower rectus abdominis, external obliques, internal obliques, and erector spinae.

Last year I conducted a test where I placed electrodes on the upper and lower rectus abdominis and the study proved beyond a shadow of a doubt that it is indeed possible to place more tension on the upper or lower rectus abdominis depending on the type of ab exercise you perform. For example, shoulder-to-hip flexion (think crunch) movements hit the upper abs harder than they work the lower abs, whereas hip-to-shoulder flexion (think leg raise) movements hit the lower abs harder.

Below is an example from last year’s study that illustrates this phenomenon. Please note that the MVC for this experiment was obtained by simply flexing the abs as hard as possible from a standing position, which explains the relatively large percentages.

 

Exercise	Upper Rectus Abdominis Activity	Lower Rectus Abdominis Activity
50 lb Weighted Swiss Ball Crunch	438.0 mean % 1205.0 peak %	136.0 mean % 248.0 peak %
Lying Leg Throw	224.0 mean % 474.0 peak %	273.0 mean % 595.0 peak %

Advantages and Disadvantages

Some exercises have inherent advantages in terms of EMG activity while other exercises have inherent disadvantages.

For example, weighted uni-planar isolation core exercises with high levels of stability almost always equate to high levels of muscle activation. Case in point: the weighted crunch. How could it not activate a ton of rectus abdominis musculature? You’re lying on your back on a stable floor while isolating sagittal plane trunk flexion.

On the flip side, total-body multiplanar integrated core exercises with a degree of instability sometimes equate to lower levels of activation. Case in point: half-kneeling cable chops and lifts. These lifts are integrated diagonal patterns based on PNF principles that teach the core how to produce quality movement that isn’t specific to any single muscle.

Although these total-body multiplain exercises don’t necessarily elicit high levels of core EMG activation, they’re very worthwhile because they correctly train the stabilization and force transferring function of the core (as Gray Cook has touted for ages).

A lot of guys need to get away from rectus abdominis dominance (trunk flexion, posterior pelvic tilting) in order to allow for the inner core unit to effectively perform its task of stabilizing the spine during movement.

Also, the external oblique activity of every rotational exercise was at a disadvantage because I placed the electrodes on the same side as each other for each muscle tested. So I tested right-side external oblique activity along with right-side internal oblique activity.

Although both sides of the internal and external obliques are active during rotational exercises in each direction of rotation (right and left), the external obliques are known to be more active in opposite side rotation while the internal obliques are known to be more active in same side rotation.

For example, a half-kneeling cable chop to the right would activate more left-side external oblique and right-side internal oblique. Since I tested both right-side internal and external oblique for each rotational exercise and failed to test the activity going in the opposite direction, external oblique activity may not be truly represented for rotational exercises in this experiment. However, past research that I have conducted indicates that the difference isn’t as pronounced as one would think.

Isometric core exercises have a distinct advantage for mean activity because there are no periods of reduced muscular activity at the start or end of the repetition. The muscles are highly activated right at the start until the end of the set.

On the contrary, an exercise like the Turkish Get Up is at a disadvantage in terms of mean activity because the lift is so complex and has so many phases that there are periods where certain muscles aren’t working very hard, which reduces the levels of mean activation.

Confirmations

The good ol’ ab wheel

We’ve always known that crunches and hanging leg raises work a ton of rectus abdominis muscle. Anyone who’s performed a couple of sets of ab wheel rollouts can attest to the intense levels of rectus abdominis activity that are necessary to prevent the lumbar spine from extending throughout the exercise—and the soreness they produce the following day or two.

The bodysaw is similar to the ab wheel rollout in that it’s an anti-extension core exercise that involves increasing the lever arm throughout the movement to place more tension on the core.

Kettlebellers were right?!

The kettlebell community has praised the core-activating benefits of the Turkish Get Up (TGU) for many years. It’s taken quite a while for some strength coaches to catch on but nowadays most coaches are having their athletes perform the TGU in their warm-ups. The TGU was the only exercise in this experiment that had over 100% peak activation in all four core muscles that were tested. Good job kettlebellers!

A final confirmation is the reverse hyper. Louie Simmons has been touting its lumbar-targeting abilities for ages. He too was right—it’s one hell of an erector spinae exercise.

Safe Core Exercises for Your Pelvic Floor

Circumstances that put women at high risk of pelvic organ prolapse with intense abdominal exercise include:

• Recent pregnancy or childbirth
• Menopause
• Being overweight or obese
• Recent surgery (including hysterectomy, prolapse surgery, and others)

If you are at risk for pelvic floor injury, it’s important to avoid exercises that cause excessive stress on the upper abdominal muscles. Avoid sit-ups, crunches, and floor exercises where both legs are raised off the floor at once. Here are safe abdominal exercises, and those to avoid.

Safe Ab Exercises

• Modified Plank: On hands and knees, extend your left leg back and your right arm forward and then bring back to center. Repeat 10 times. Switch leg/arm and repeat 10 times.
• Diaphragm Breathing Exercise: Diaphragmatic breathing helps strengthen the entire core. Lie on your back with knees bent and hands resting on lower abdomen. Exhale, expelling all your air, then slowly inhale until your lungs are full. Repeat 10 times.
• Clamshell: Lay on your side with knees bent and your head propped up by one arm. Raise your outer leg, hold for a few seconds, and then lower. This position engages your obliques and abs gently. Do several sets of 10 reps.
• Kegels: With or without a Kegel exercise device, Kegel exercises are the ideal way to exercise your pelvic floor—part of your core. You can do Kegels sitting, standing, or lying down, although if you’re using a pelvic floor exerciser you’ll need to be lying down. Contract your muscles as though you’re stopping the flow of urine. Hold for five seconds and repeat. Aim for five minutes of Kegels every day. The bonus: Kegels can enhance sexual experience and lead to more intense orgasms.
• 
• Modified double leg raises: Double leg raises are popular in Pilates and floor exercise classes, but they put a lot of strain on the pelvic area. Modify the move by raising only one leg and keeping the head and shoulders in constant contact with the floor. Repeat 10 times with each leg, and don’t forget to breathe normally throughout.
• Squats: Stand upright with feet shoulder-width apart. Keep the heels firmly on the ground, and with back straight, bend at the waist, then the knees as it you’re about to sit down into a chair. Don’t lean forward as you squat; rather, “sit down” into it. Move up and down slowly, and do at least two sets of 10 reps.

Surprises

A hardcore plank?

A while back a colleague of mine named Joe Sansalone taught me how to do an RKC (Russian Kettlebell Challenge) plank. Basically, he had me get into my normal plank position and then made adjustments. First, he had me place my elbows slightly further out in front of me and closer together to increase the lever arm length and reduce the width of the base of support. He then had me forcefully lock out my knees by contracting my quads.

Finally, he had me contract my glutes as hard as possible to the point where my pelvis posteriorly rotated. These adjustments left me quivering like a school girl. I highly recommend experimenting with this new variation as it blows away the core activation of a normal plank.

Don,t ignor to do this kind of exercise

Stomach crunch

Target: abdominal muscles

Lie on your back, knees bent and feet flat on the floor, hip-width apart. Place your hands on your thighs, across your chest or behind your ears. Slowly curl up towards your knees until your shoulders are about three inches off the floor. Hold the position for a few seconds and lower down slowly. Perform 12 stomach crunches.

Tips:

• Don’t tuck your neck into your chest as you rise.
• Contract your abs throughout the exercise.
• Don’t yank your head off the floor.

Oblique crunch

Target: oblique muscles 

Lie on your back, knees bent and feet flat on the floor, hip-width apart. Roll your knees to one side down to the floor. Place your hands across your chest or behind your ears. Slowly curl up towards your hips until your shoulders are about three inches off the floor. Hold the position for a few seconds and lower down slowly. Perform 12 oblique crunches and repeat on the opposite side.

Tips:

• Don’t tuck your neck into your chest as you rise.
• Contract your abs throughout the exercise.
• Don’t yank your head off the floor.

Plank

Target: lower back and core muscles

Lie on your front propped up on your forearms and toes. Keep your legs straight and hips raised to create a straight and rigid line from head to toe. Your shoulders should be directly above your elbows. Focus on keeping your abs contracted during the exercise. Hold this position for 5 to 10 seconds and repeat 8 to 10 times.

Tips:

• Don’t allow your lower back to sink during the exercise.
• You should be looking at the floor.
• For an easier version, perform the plank with your knees on the floor.

Side plank

Target: lower back and core muscles

Lie on your side propped up on an elbow. Your shoulder should be directly above your elbow. Straighten your legs and raise your hips to create a straight and rigid line from head to toe. Keep your neck long and your shoulders down and away from your ears. Keep your abs contracted during the exercise. Hold this position for 5 to 10 seconds and repeat 8 to 10 times. Repeat the exercise on the other side.

Tips:

• Keep your hips forward during the exercise.
• Don’t let your lower back sink.
• For an easier version, perform the side plank with your knees on the floor.

Stomach crunch with legs raised

Target: lower abdominals

Lie on your back with your knees bent and feet flat on the floor, hip-width apart. Place your hands across your chest. Slowly pull your knees into your chest, keeping them bent at 90 degrees, until your buttocks and tailbone come off the floor. Hold the position for a moment and lower down slowly. Perform 12 crunches.

Tips:

• Contract your abdominals throughout the exercise.
• Don’t tuck your neck into your chest as you rise.
• Don’t use your hands to pull your neck up

References

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