But the craze for buff abs isn’t only about looking good without a shirt. Training the abs is often associated with vanity, but that perception is changing, thanks to the "core fitness" principles espoused by high-profile professional trainers like Chris Robinson, author of The Core Connection, trainer to celebrities, Pilates expert, and champion Muay Thai fighter.
"Every movement should initiate from the stomach region," Robinson says. "If you curl your little finger, you should still feel your stomach."
The abs, also known as the rectus abdominis, are bands of muscle connecting the pelvis with the rib cage. It’s these muscles that form a "six pack" when they’re well developed and not hidden under belly fat. The abs get the most press, but they don’t work alone. They function with a group of other so-called "core" muscles, including the obliques, which wrap around the sides of the torso, and muscles that move the spine and pelvis.
The core muscles are important because they connect the upper and lower body; they’re essential for the coordinated movement of the whole body. Strengthening the core muscles can make you more fit for all kinds of activity.
Strengthening Your Abs
Having relatively weak abs compared to your back muscles can make you more prone to muscle injuries and lower back pain. The back is normally somewhat stronger than the abs, but there shouldn’t be a drastic imbalance between them, says William Kraemer, PhD, an exercise physiologist at the University of Connecticut and a member of the American College of Sports Medicine.
"It’s always a relationship between the front and back. You’ve got to train both sides of the body," he says.
Robinson says he sees more men than women with greater strength in the back muscles than in the abs. "Ninety percent of my male clients, as opposed to 20% of my female clients, have that issue."
How to Get Flat Abs
Ab workouts alone don’t necessarily produce flat abs. If you have a lot of belly fat, you also need to consume fewer calories than you burn. For weight loss and general fitness, aerobic exercise and strength training are important.
Choosing an exercise for a specific fitness goal is like picking a tool out of a toolbox, Kraemer says. The right tool for the job isn't always the most powerful or complicated. "If you’re going to put up a picture in your house, you’re not going to use an air hammer to do it," he says.
He says the core muscles don’t need "heavy loading" with weights. Effective training makes them stronger but not bulkier. "Mass in the abdominals is based on the amount of muscle fibers that are there genetically," he says. Because you can’t pump up your abs beyond a certain genetically predetermined size, he says, the chiseled look accomplished with physical conditioning comes mainly from having scant abdominal fat covering the muscles.
There are any number of exercises that, along with a balanced fitness regimen and a healthy diet, could help you get strong, flat abs. No ab exercise is perfect, Kraemer says. "Many approaches work. There’s no one size fits all."
Here are a few ideas to get you started.
Flat Abs Exercise: Traditional Crunch and Sit-up
The traditional crunch could be called the plain vanilla of ab exercises, but it works and is worth knowing how to do properly.
Most guys with gladiator-quality abs have put enough effort into physical training to know the difference between a crunch and a sit-up. If your DVD collection is conspicuously lacking in the fitness category and your gym membership lapsed long ago, you might need a little clarification, though.
The difference between a crunch and a sit-up is where you bend. To do a sit-up, you literally sit up from a prone position, bending at the waist until you touch your elbows to your knees. To do a crunch, you squeeze your abdominal muscles to bend your rib cage toward your pelvis, as if you are trying to sit up but can’t because an imaginary strap is holding down your abdomen and hips.
Lay flat on your back with your knees bent and feet on the floor. Place your hands loosely behind your head and spread your elbows out so that your shoulder blades squeeze together. Keeping this posture, contract your abdominal muscles, lifting your upper body without arching your back. The lower back should stay flat to the ground. The hips and legs should not move. Stop at the point where you can’t go any farther, hold it, and then slowly relax, returning to your starting position.
Get it right:
- Go slowly, and focus on good form. Doing crunches too fast could make your form sloppy and strain your back muscles.
- A set of 15-25 crunches or sit-ups is enough, Kraemer says. "I think the big mistake that people make is they try to do hundreds."
Flat Abs Exercise: Reverse Crunch
You can do the crunch in reverse by keeping your upper body flat on the ground while lifting your legs and lower torso, instead of the other way around.
Lay flat on your back with your knees bent and feet on the floor. Spread your arms out to the sides of your torso, palms down. Keep this posture while bringing your knees back and feet up so that your bent legs make a 90-degree angle. Keep your legs at that angle while you lift and roll your hips back toward your rib cage. Your upper body and head should stay flat on the ground, with your outstretched arms balancing the weight of your legs. Take it as far as it will go without moving your arms or upper body, hold the position briefly, then slowly let your legs down.
Get it right:
- Don’t let your knees wobble out of line with your hips. More of the effort focuses on the abs than related muscle groups when the legs are centered.
Flat Abs Exercise: Bicycle Maneuver
A study commissioned by the American Council on Exercise (ACE) compared the effectiveness of various ab exercises to the traditional crunch. The bicycle maneuver stood out among the 13 exercises tested by researchers at the San Diego State University Biomechanics Lab. Researchers used electrodes to measure activity in the muscles of people exercising. Compared to the traditional crunch, the bicycle maneuver produced about two and a half times as much activity in the rectus abdominis, and nearly three times as much activity in the obliques.
Here’s how to do this exercise:
Lay flat on your back and place your hands loosely on the sides of your head. Raise your legs, bending the knees at a 45-degree angle, keeping your lower back flat to the ground. Then move your legs as if your feet were pushing the pedals of a cycle. As you "pedal," touch your elbow to the opposite raised knee -- right elbow to left knee, left elbow to right knee.
Get it right:
- Don’t hold your breath. Breathe evenly throughout the exercise.
Flat Abs Exercise: Stability Ball Crunch
Crunch exercises can be more effective when done on a big inflatable ball called an exercise ball. The ACE-commissioned study of ab exercises showed that crunches done with the aid of an exercise ball generated 39% more activity in the rectus abdominis, and 47% more activity in the obliques than a traditional crunch done on a floor mat.
Sit on an inflated exercise ball, feet flat on the floor. Roll down on the ball, so that the middle of your back rests at the top of the ball. Hold your thighs level with the floor, knees bent at a 90-degree angle. Place your hands behind your head with your elbows pointing outward, squeezing your shoulder blades together. Contract your abdominal muscles, curling your chest toward your pelvis. Keep your lower back in contact with the ball and your feet firmly set on the floor. When you’ve taken the crunch as far as you can, hold it a moment, then slowly relax, returning to the starting position.
Get it right:
- Use a properly sized ball for your height. A ball 26 inches in diameter is recommended for men 5 feet 8 inches to 6 feet 2 inches tall.
- A more fully inflated, harder ball makes for a more difficult workout. A properly inflated ball should give slightly under your weight.
Flat Abs Exercise: The Plank
There are many variations of this exercise, which as the name suggests, involves a rigid, straight posture. A basic plank exercise is similar to a push-up. Robinson says it’s an important ab exercise to start with because it helps people become aware of their core muscles. Holding your body rigid, you can feel how those muscles keep you from collapsing, he says.
Lay on your stomach with your arms bent, keeping your forearms flat on the floor, palms down. Your elbows should be in line with your shoulders and close to your sides. Bend your feet forward so your toes grip the floor. Stiffen your torso and legs. Slowly raise up your whole body, keeping your legs and torso in a straight line, without letting any part sag or arch up. Hold the position and then lower yourself back down.
Get it right:
- If you feel any lower back pain while doing this exercise, stop right away.
Flat Abs Exercise: Pilates
Pilates isn’t a single exercise. It’s a fitness system that involves many different exercises and routines that can be done on exercise mats or with a special machine. Many people practice Pilates with a certified instructor at a health club or private studio, but instructional books and videos are also available for doing it at home.
Pilates is increasingly popular. An annual survey of health and fitness professionals conducted by the American College of Sports Medicine lists it among the top 10 "fitness trends" for 2010.
Robinson says he trains people in a variety of fitness techniques, but he thinks that Pilates is "the best core exercise modality out there."
If you have the impression that Pilates is somehow unmanly, consider Robinson. Here is a guy who is Oprah’s personal trainer and a punisher in a martial sport that can make Western boxing look like patty-cake. He says that his Pilates and Muay Thai martial arts training are all of a piece.
Kraemer says he thinks the main benefit of Pilates is the novelty of exercises involved, which get people to move in ways they normally wouldn’t. But he cautions against following any "prepackaged" exercise program exclusively because they all have different strengths and weaknesses.
Flat Abs Exercise: "As Seen on TV"
You’ve probably seen TV ads for ab exercise devices. Studies have shown that some of these devices were more effective than the traditional crunch, while others were about the same or less effective.
The ACE-commissioned study included tests of the Ab Roller, Ab Rocker, and Torso Track. Of the three, the Torso Track performed the best, generating a little more activity in the rectus abdominis than the traditional crunch, but a significant number of users reported lower back discomfort. There was practically no difference between the Ab Roller and the crunch. The Ab Rocker was shown to be much less effective compared with the crunch, generating about 80% less activity in the rectus abdominis.
Another study, published in the journal Physical Therapy, compared several ab exercises, including the traditional crunch and two patented exercise devices. The study was conducted by academic researchers at California State University in Sacramento, Calif.
Four different exercises using a device called the Ab Revolutionizer were all shown to be less effective than the traditional crunch. The researchers also tested the Power Wheel -- a small treaded wheel with handle grips. They found one technique using the Power Wheel to be the most effective of 12 exercises tested. That technique, called the "roll out," involved gripping the wheel and rolling it forward from a kneeling position.
Kraemer says he thinks most commercial ab exercisers he’s seen aren’t bad; they’re just nothing special. An ab device may be advertised as a breakthrough in fitness, but it’s probably just a prop for doing a sit-up or a crunch, he says. "It’s not better. It's just another thing."