A six-pack has long been considered something of a holy grail when it comes to fitness goals. (Not to be confused with the ab crack.) But they're so revered at least in part because they're so (annoyingly) hard to achieve.
In fact, a convo during one of Shape.com's regular brainstorming sessions revealed that many of us have gotten stalled out with a "two-pack"—amazing definition in the top ab area, toward the bottom of the ribs...which just melts into the rest of the stomach. What does it take to unearth the other four abs? (Try this 10-minute routine that works your whole core.)
Well, it helps to have ripped parents—at least according to Harley Pasternak, a celeb trainer and founder of the 5-Factor Diet. He says that though we often hear about "upper abs" and "lower abs," as if we have six separate pockets of muscle dotting our midsection, it's actually all on the same swath of muscle. But it's divided into sections by fibrous bands called the "tendinous intersection," which creates the six-pack illusion. "Most people have a genetic predisposition to where those lines are," Pasternak says, joking that the most effective way to get a six-pack is to "pick your parents carefully."
Besides fibrous band placement, women may be more prone to the two-pack issue because they have shorter upper torsos and longer legs than men. A shorter torso means you have a smaller "palette" for your abs to appear, and your lower ones kind of disappear.
But there are a couple things you can do to increase your ab count. The first is easy: Throw your shoulders back. Pasternak says that women tend to round their shoulders forward, possibly because of the weight of their breasts, which shortens their torso even further. Standing up straight makes the most of your abdominal palette. (These yoga poses can help you beat the slouch.)
The other tip is something you've heard before—reduce your body fat. "Fat in the ab area obscures the definition of the tendinous intersection," Pasternak says. That said, women naturally carry more body fat than men—necessarily so, since they need it to maintain hormone production, he notes. Whether you can lose enough to show off a full set of abs without affecting your health may go back to your genetic makeup. In other words, you may be able to have a perfectly flat, toned stomach, without necessarily having a defined six-pack. That doesn't mean stop doing ab exercises altogether—a strong core has benefits far beyond the aesthetic ones.