April 18, 2017

By Evin Billington

We love following talented yogis on Instagram, from "Yoga Girl" Rachel Brathen to Jessamyn Stanley. The poses that seem to get the most "likes" on the social network often involve gravity-defying bends or headstands against amazing backdrops (such as the incredible Aruba beaches where Brathen practices). But the latest move we've been seeing everywhere is a little different. Called nauli, it's an advanced core-strengthening technique that's weirdly mesmerizing—and Instagrammers who attempt it are racking up thousands of views.

Nauli involves sucking in the stomach, then flexing the abdominal muscles back and forth. The result, which resembles a wave, has to be seen to be believed. (Check out the video above.) Enthusiasts claim the strange-looking move aids digestion and strengthens your abs. But should you try it?

"[Nauli] is actually quite uncommon," says Kristin McGee, a celebrity yoga instructor and Health's contributing yoga and wellness editor. "I remember learning this at an ashram years ago when I was first doing my yoga teacher training. It’s not typically practiced in your general yoga class."

Nauli may help advanced yogis master poses that require lots of abdominal control, such as headstands and arm balances, says McGee, but it is extremely difficult to master. She also warns that doing it incorrectly could give you an upset stomach, or cause you to become lightheaded from breathing incorrectly.

According to gastroenterologist Roshini Raj, MD, Health's contributing medical editor, nauli is probably not harmful to your internal organs, but over-exercising the abdominal muscles could lead to a breakdown of muscle tissue called rhabdomyolysis, which in turn can cause kidney damage.

"If you are repeatedly stretching or contracting one muscle group too much, you can damage those muscles," Dr. Raj explains.

If you're interested in yoga for better digestion, you may want to try some less-advanced poses that help stimulate the digestive tract, such as lunging twists, cobra, and child's pose. And if you still want to try nauli, McGee recommends doing it on an empty stomach and learning with the help of a certified yoga instructor to make sure you're doing it correctly.