Try 1 month for 99¢

Everybody with a gym membership has seen a sweaty, exhausted gym rat, such as the guy who lifts weights all afternoon until the back of his shirt is dripping.

Everybody with a gym membership has seen a sweaty, exhausted gym rat — the guy who lifts weights all afternoon until the back of his shirt is dripping or the woman who has been pounding the treadmill for hours.

Are they getting the hoped-for benefits of their long workouts? Are they efficiently building muscle or losing weight? The answer is likely no. Long workouts are not efficient. In fact, working out for too long actually decreases the results.

The biggest reason for diminishing returns with a long workout is that your body gets tired. You can't keep up the pace on the treadmill, or you can no longer move the weight through the full range of motion. If you try to keep going, you'll just slow down. You'll lose any semblance of proper form.

The right form is essential in any kind of physical conditioning. Suppose you're doing biceps curls with a set of dumbbells. If you have been working out so long that you've exhausted every fiber in your biceps muscle, you won't be able lift the dumbbell with a smooth fluid motion all the way up to your shoulder. You'll be a lot weaker than you were at the beginning of the workout.

That's not to say that you shouldn't tire your muscles when training. Working your muscles until they are tired is a good thing. But if you have exhausted muscles so deeply that they can't perform exercises with proper form, you're actually hurting yourself.

The most important part of gaining strength comes after training, when the muscles rebuild themselves after the stress of the workout. Muscles recuperate by becoming stronger, so that they are not exhausted by that same level of stress. But if the muscular stress was too prolonged, and the long workouts happen too often, the exhausted muscle may not fully recuperate. This condition has an actual clinical name: overtraining. It can take months, many months, for a group of overtrained muscles to recover.

Many exercise specialists today recommend that a good workout program should last about an hour — no longer. They suggest that those athletes who wish to train for a longer period of time break up their session into two parts: one hour in the morning, followed by a protein-based meal and several hours of active rest, with another one-hour session later in the day.

In fact, the best exercise program is to do one-hour workouts four days a week, rather than exhaust your body with longer workouts done fewer times a week. With one-hour workouts, you'll gain strength and muscle, without the negative results of overtraining or overtiring your body.

Wina Sturgeon is the editor of the online magazine Adventure Sports Weekly, which offers the latest training, diet and athletic information.