Weight Loss Despite lots of arguments about the details, most experts agree that weight loss is a matter of energy balance-consistently burn more calories than you take in, and you'll lose weight. (And, unfortunately, vice versa for gaining weight.) Because it allows you to burn a good amount of calories in a relatively short time, running can be a key component of an effective weight-loss program. If you have weight to lose, you didn't gain it overnight. Instead, it was probably a gradual accumulation that at some point became significant. That's worth keeping in mind when coming up with a weight-loss program-research shows that your best bet for long-term success is combining exercise with reasonable calorie restriction, and focusing on the long view. Crash diets, in contrast, can result in more dramatic short-term weight loss, but generally aren't sustainable for long, and can place your health at risk.