There’s been a lot of talk lately about a new study conducted by researchers at Louisiana State University that showed that increasing exercise doesn’t cause weight loss. In fact, people who exercised the most in this study were actually more likely to gain weight than those who exercised least. Despite the buzz, the idea that exercise doesn’t help you lose weight is actually old news; there have been dozens of studies that have shown the same thing. And anyone who knows anything about the calorie content of things we typically eat every day – the lattes, the pastries, the pizza, the fast food burger– can logically figure out why this should be the case. Unless you are doing extremely vigorous exercise for a very long time, you simply cannot burn enough calories to offset the amount you can easily eat in a couple of innocent bites cheese and crackers. Furthermore, exercising often makes people hungry. Whether the hunger is truly biological (compensating for “lost” calories) or psychological (“hey, I had a great workout today – I can eat that extra slice of pie”) is moot since either way it means calorie intake goes up and weight won’t go down.

So, at this point you might be thinking that maybe you should skip the workout – but there’s a lot more to this story than these reports suggest. First of all, while exercise may not help you lose weight, it is absolutely essential for keeping the weight off once you’ve reached your goal. And, in fact, significant amounts of exercise are necessary to maintain weight loss – as much as 60-90 minutes a day for people in the National Weight Control Registry, a national database people who have successfully lost an average of X pounds and kept the weight off for at least X years.. Because most of us are unlikely to go directly from being a couch potato to exercising an hour a day (and this isn’t recommended!), it is really important to begin to gradually increase exercise as soon as you start a weight loss program so that by the time you reach your goal weight, you are in a regular habit of daily exercise and can maintain your weight loss success.

The second thing that is often overlooked is that there is a gender difference in the response to exercise in terms of weight loss. The LSU study was conducted only in women. Previous research shows that women are much more likely than men to compensate for calories burned in exercise by either eating more or burning less during the non-workout portions of their day. For example, in one study, men and women trained for a half-marathon event using identical training regimens. By the end of the study, the women were actually burning fewer total daily calories than when they started, even including the calories burned during the lengthy runs, because their metabolism slowed down so much during the non-running hours! While as a woman I find this particularly depressing, if you are a man, it’s really good news because it means that exercise might actually help you lose weight. In one large study called the Weight Loss Maintenance Trial, it was found that the more minutes men exercised each week, the greater their weight loss (in women, unfortunately, there was no relationship between more exercise and greater weight loss). So, use this to your advantage, guys!

Lastly, there are obviously many more reasons to exercise than simply the number on the scale. Just a few of these reasons include the fact that exercise extends lifespan, reduces risk for many chronic and debilitating diseases (like diabetes and heart disease), makes you think more clearly, improves sleep, and reduces stress. And these health benefits are all independent of weight. So go on and lace up your sneakers and get out there – there are lots of great reasons to work out!