Emily Ratajkowski has one. So does Jasmine Tookes, and the entire Victoria’s Secret Fashion Show posse, now that I think about it. However, most women don’t, have never and probably will never obtain one. I’m talking about “ab cracks.”
Source: Instagram
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First coined in July 2016, the ab crack is essentially the divide between your abs (well, between some people’s abs) that’s basically the six pack’s less-flamboyant cousin. According to celebrity trainer Joey Thurman, the ab crack actually has a clinical name, and it’s pretty much reserved for people willing to live at the gym and give up carbs for life.
“What you’re referring to is the linea alba,” Thurman told us. “This is the fibrous tissue between the abdomen that generally shows up when you are incredibly lean and have great abdominal definition.”
In addition to exercising really, really hard (more on that later), anyone chasing a defined, um, linear alba, should sleep more and eat less refined foods.
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“Without proper sleep, your body will be inflamed, you won’t burn as much fat, you will crave more calories—and the bad ones—and your cortisol levels will be elevated, limiting any sort of fat burning,” says Thurman. He also says the most important part of getting to actually see your abs is diet: “Avoid any processed carbohydrates and added sugar—so nothing from a bag, no bread, no cereal and no sweets. Also, drink lots of water, because if you don’t drink water, your body holds on to it.”
Of course, you’re not going to get off that easy—ab cracks of hashtag-worthy proportions are also sculpted at the gym. So while you’re mulling over whether an ab selfie is worth giving up pizza, click through the slideshow for the 14 ab exercises recommended by celebrity personal trainers.
A version of this article was originally published in November 2016.