This article was written by Kit Fox and provided by our partners at Runner's World.

You don’t need super heavy weights to torch calories. In fact, according to research from the Human Performance Laboratory at the University of Wisconsin-La Crosse, your own four limbs—plus a willingness to push your body to the brink—can burn more cals than just about anything else.

For the 2013 study, 16 fit adults participated in a 20-minute bodyweight circuit, which included exercises like pushups, burpees, squats, and lunges. John Porcari, the lead researcher and head of the university’s performance lab, says the participants burned an average of 15 calories per minute, nearly twice the rate expended during a long run. (Dance your way fit with High-Intensity Dance Cardio, the first-ever socanomics DVD!)

The key to the efficient burn is effort, says Porcari. “You should be feeling extremely uncomfortable. If you aren’t exhausted by the end of this workout, you aren’t doing it right.”

The researchers modeled the circuit after high-intensity interval training (HIIT), a workout style that includes periods of intense effort followed by a short recovery.

Learn more about interval running:

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In the study, participants completed an exercise all-out for 20 seconds then rested for 10, repeating the process in five, four-minute segments.

“What it all boils down to is overtraining specific metabolic systems,” says Porcari. “You can only run a race at a certain pace for so long. When you do high-intensity interval training, you shift that threshold up. It’s why athletes do intervals.”  

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For runners looking to incorporate a bodyweight HIIT routine in their normal training, Porcari recommends keeping it to once or twice a week, allowing plenty of time for recovery between sessions.