Redefining Great Abs
Many fitness enthusiasts focus on developing the "six-pack" muscle, or rectus abdominis, which is actually a "10-pack" that runs from the pubic bone to the breastbone. "A straplike muscle designed for smooth, long movement, its main purpose is to raise your body from bed each morning," Seabourne explains. "The rectus is the most superficial and visible of four abdominal muscle groups that work synergistically."
The internal and external obliques, on the sides of the torso, rotate and bend the torso. "Your obliques are used in almost every activity," Seabourne says. Twisting is the key to training them.
The deepest layer is the transversus abdominis, which is located horizontally underneath the rectus abdominis and the obliques. One of the few muscles with fibers that run from side to side, the transversus generally functions along with the autonomic nervous system to flatten the stomach in "bearing-down" activities, such as childbirth and defecation, and is activated in expelling actions, such as coughing and vomiting.
Yoga is excellent for building healthy abdominals, Seabourne says, because it involves moving the body in various directions and angles through postures requiring stability and balance--often in an unusual relationship to gravity. "The key is flexible strength, and that's what yoga develops," he explains. "Too many people still think ab training is doing crunches, which does nothing for flexibility. If you just train for strength, your muscles can actually shorten. And if you train in only one direction, you're limiting your range of motion."
Building strength and flexibility in the abdominal and back muscles, which form the body's "core," is the main goal of Pilates--one of the most rapidly growing exercise systems in the nation. Unlike in yoga, students in Pilates always "exhale through pursed lips, because this creates a resistance that helps people feel the abdominal contraction," says Moira Merrithew, program director of Stott Pilates in Toronto. Throughout all Pilates exercises, she says, the inhalations are done through the nostrils and the exhalations are done through the mouth to help students focus on their core and strengthen the deep abdominal muscles.
Several classic Pilates exercises focus on strengthening the abs, with the goal of creating "optimal functional fitness," Merrithew says. One of the best known is the "hundreds," performed supine with the head and shoulders raised while the arms pump up and down by the sides in time with the breath to the count of a hundred.
To help people learn the often subtle engagements of the abdominals, "hands-on work is invaluable," says Michael Feldman, a certified Rolfer in Sausalito, California, who teaches functional-anatomy workshops. He suggests that instructors teach people how to engage the transversus by first palpating the hip points at the front of the pelvis, then asking the person to "draw the two hip points together by lengthening the back and hollowing the belly." Another important aspect is finding the sitting bones, "so people can learn to sit on them properly," Feldman says. "One reason the abdominals are so weak is that most people sit with their backs rounded, which makes the abs go slack."