A new study released by the University of Alabama in Birmingham revealed that sex is not the fat burner and physical workout many once believed. Results showed that during an average sexual encounter – which researchers determined to be 6 minutes in length – the average person burned only 21 calories. Other studies used the average sexual encounter time of one hour, an intimate experience that would leave you physically unable to function for the next day or two. We're going to completely disregard this study and maintain our ignorance by believing sex burns hundreds of calories and therefore the gym is overrated. But that's just us.