The hottest new fitness trend is a real throwback... to when you were in diapers! Crawling is a great workout and to explain why The Doctors are joined by fitness expert PJ Stahl. 

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"It takes us back to our primitive patterns. It takes us back to when you were a child. When you initially learn locomotive patterns... you actually start crossing neuro-patterns from right to the left side of your brain. It's the first time it starts to happen when we start moving. it's so important because it builds your core, builds your shoulders, and it builds your hips. As we get older, we don't do it." So PJ is changing that by putting it back into workouts!

PJ demonstrates this move which is done on all fours, with your hands on the floor, and your knees hover off the ground to activate your core. Plastic surgeon Dr. Andrew Ordon calls it, "a moving plank."

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PJ shows off many different levels of difficulty in the video above, but ER physician Dr. Travis Stork advises viewers to enlist the help of a trainer, like PJ, to make sure you get the form correctly to avoid injury.