The Kardashians are "obsessed." Jessica Alba claims it helped her return to her pre-baby body. But what exactly is "waist training," and does it work? More importantly, is it safe? We talked with health and fitness experts to get the skinny on Hollywood's latest must-have accessory: a modern-day corset.
Famous sisters Kim and Khloe have fueled plenty of interest in this trend, by posting Instagram photos of themselves in recent months wearing waist-training devices—essentially, bands of material that wrap tightly around the waist and lower rib cage to provide an instantly slimming, hourglass look.
Other models and celebs have touted the benefits of waist trainers, while actresses Brooke Burke-Charvet and Jessica Alba have credited similar products with helping them get back into shape after giving birth. (Alba says she wore an actual corset.)
Burke-Charvet even created her own line of waist wraps; one is designed for new moms and intended to reduce water retention and swelling of the uterus, "all while supporting that unwanted baggy baby skin." Another product—a sport body wrap made of nylon and neoprene—is meant to be worn around the waist during exercise, with the intention of promoting "intense sweating."
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But do they deliver?
Not if you're looking for anything more than temporary results, says Caroline Apovian, M.D., professor of medicine at Boston University School of Medicine and a spokesperson for The Obesity Society.
"If you're going out and want to look really thin, I don't see a problem with wearing one of these for an evening," she says. In fact, wearing a waist trainer may even help boost some women's confidence and encourage them to exercise and eat healthy. "If you look in the mirror and like what you see, it can potentially be a good thing."
But as for the claims that these devices can actually reshape the body or trigger fat loss, there's no evidence. "In my opinion, that is complete nonsense," Dr. Apovian says.
In fact, some experts believe that regularly wearing a waist trainer can actually decrease core strength—exactly the opposite of what you want if you're aiming for a sexy stomach, says celebrity trainer Nicole Glor.
What are the risks?
If a waist trainer is too tight—which many of them appear to be, if recent celeb photos are any indication—it could cause discomfort, interfere with breathing, or contribute to heartburn. "Your stomach might get pushed up beyond the diaphragm, which could cause reflux," says Dr. Apovian. "If you're wearing one and you experience those symptoms, that's a definite sign that you need to loosen it or take it off."
Wearing a waist-cinching device for a workout isn't a good idea either, says Glor, especially if it restricts your mobility or your ability to take full, deep breaths. "It can really affect your ability to work hard," she says. "Plus, I would worry about back acne from the tight apparatus and extra sweat."
What about for new moms?
Working out with a tight (but not too tight) waist band may help women who recently gave birth feel more comfortable, says Dr. Apovian. "If it helps everything feel a bit tighter and there's less jiggle around your stomach, it may help you feel better about exercising."
But having some extra support around the waist shouldn't be an excuse for new moms to push themselves too hard or too fast, she says. And the devices' other purported post-baby benefits are much less convincing. "The uterus is going to shrink when it feels like shrinking," she says, "and you can't get rid of water weight with a corset—that's simply not true."
Glor says she was instructed by a physical therapist to wear a post-natal waist band during certain core exercises after she had a C-section, because she'd developed a condition called diastasis recti that caused her ab muscles to separate and her intestines to push through the abdominal wall.
However, she says the device itself didn't do much to help her condition. "And if it couldn't fix the abs that were recently forced to separate, that doesn't bode well for other women's waistlines that has been formed over many years," she points out. "Seems like a lot of pain, no gain."
The bottom line
Waist trainers won't have any lasting effect on waist size, shape, or appearance, Dr. Apovian says. They'll make you look slimmer while you wear them, but you may have to put up with some discomfort—and maybe even some health risks—in return.
If you want tighter abs, Glor says, core exercises like planks (see video below) and twisting crunches can help define those stomach muscles. And to really lose inches around your waist, you have to do it the old-fashioned way: with proper nutrition and hard work, in the form of moderate- to high-intensity exercise. "People are always looking for a way to cheat or a quick fix to fitness, and the answer is there isn't one."
Video tip: How to do a perfect plankIt's all too easy to cheat at this move, and you may not even realize you're doing it. Here's how to do a plank perfectly.
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