While most people’s gym routines differ – I, for one, have always been an elliptical girl and hate the stationary bike – it’s safe to assume that almost everyone incorporates a “cool down” into their cardio program. After running for 30 minutes at 7 miles per hour, you’ll knock your speed down to 3 and spend five minutes jogging or walking before you hop off the machine. Many pieces of gym equipment even include a 5-minute cool down automatically, tacking it on to the end of your desired workout. All of this is supposed to prevent soreness or muscle damage and relieve strain on the heart.

According to University of Texas physiologist Hirofumi Tanaka, however, there’s no proof that a cool down has any positive benefits on the body. “Everyone thinks it’s an established fact, so they don’t study it,” he said in a recent New York Times article. The article notes the ambiguity of the concept as a whole, noting that it’s not even clear what a cool down is supposed to be or how long it should last.

Apparently, the cool down became standard gym practice after it was reported that muscles become sore after exercising due to the accumulation of lactic acid. This theory has been reported false, leading people to believe that reducing the intensity at the end of a workout (which was supposed to let the lactic acid dissipate slowly) is unnecessary. The article does note, however, that blood can build up in your legs and feet if you stop running (or biking or ellipti-cizing) shortly, making dizziness or even fainting a possibility.

The article adds that because lactic acid has been discovered to be beneficial, it might be better not to cool down. A study of a group of cyclists showed that cooling down wasted the lactic acid; when they just stopped without reducing their speed gradually, the lactic acid was turned into glycogen, a muscle fuel.

So what does this mean? It means that you don’t have to waste that extra ten minutes at the gym cooling down. In fact, for better results, it means that you shouldn’t. Finish your desired workout, grab your things and head home. Then use that extra time for something more productive, like studying, making a healthy snack… or stalking your crush on Facebook.