Every year, the American College of Sports Medicine polls thousands of fitness pros across the world to determine what the biggest workout trends will be. Remember when Zumba took over the internet in 2012? The ACSM totally predicted that. For 2015, however, the most popular workout is no fitness fad or flash-in-the-pan exercise (hey, remember the Shake Weight?). It's a tried-and-true workout that you might already be doing.

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Drumroll please.... Bodyweight training beat out high-intensity interval training for the top spot. And for good reason: it's basically a fancy way to describe all the good ol' moves you've been doing since you first went to the gym (think squats, lunges, pushups, planks...). It's the basics; so why is it so popular? Well, because it's the most inexpensive workout out there — all you need is your own body weight — and you can do it literally anywhere, no gym required. Bodyweight training didn't actually appear on ACSM's survey until 2013 (the first survey was done in 2006), when it debuted at number three, because it only became a "defined trend" during the last few years, according to the study authors.

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In case you need a little more excitement at the gym, you should know that HIIT workouts are still ranked at number two, followed by strength training and personal training. Spinning, on the other hand, seems to be on its way out. Oh, and Zumba, BTW? It dropped all the way down to number 28 this year (insert sad face here).

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