SHAPE UP
Exercise facts get mixed up with fallacies

By Charles Stuart Platkin

True or false? To burn the most calories, don't eat before you exercise.

False.

You don't burn more calories by not eating before you go out for your morning jog.

In fact, the opposite is true.

"If you don't eat, you won't have the energy to exercise as long, so you will burn fewer calories, not more," says dietician Nancy Clark, author of the "Sports Nutrition Guidebook."

Clark recommends eating about 200 to 300 calories within an hour of exercising.

What if you exercise first thing in the morning?

"Even eating a piece of fruit five minutes before you exercise to get your blood sugar back up to normal would be helpful. You need energy to get yourself moving and to make your workout more enjoyable and sustainable," says Clark.

What should you eat? "Try to have high-density carbohydrates, like an apple, some whole grain cereal, or a banana," says Clark. Keep in mind, these calories shouldn't be in addition to your normal diet, just redistributed from your other meals or snacks.

Muscle turns to fat without exercise.

False. Muscle is muscle, and fat is fat. You can't transform one into the other. "Muscle atrophies — that is, gets smaller — and fat accumulates, usually as a result of less activity and the same amount of eating, which might give the appearance that muscle turns to fat," says John Acquaviva, a professor of health and human performance at Roanoke College.

You need to eat extra protein in order to put on muscle mass.

False. Weight training does not significantly increase your required protein intake. "For the average person, there is no need to add protein bars, shakes, or supplements — most ordinary mortals get more than enough protein in their everyday diet to support a strength training regime to build muscle," says Clark.

"An adult trying to build muscle mass should have about 0.7 to 0.8 grams protein per pound of ideal body weight," says Clark. So, if you're trying to build muscle and weigh about 150 pounds, you might need about 112 grams of protein per day. Keep in mind that one six-ounce chicken breast has about 50 grams. What happens if you go overboard? You will not be fueling your muscles with the proper fuel mixture.

If you don't work out for at least 60 minutes, why bother?

False. The confusion is understandable given the mixed messages that are out there. The Institute of Medicine recommends an hour each day of moderately intense physical activity to maintain cardiovascular health at a maximal level (and for the best weight loss and weight control results).

On the other hand, the American College of Sports Medicine and the U.S. surgeon general both recommend approximately 30 minutes of exercise three to five days per week for decreased disease risk and increased longevity.

"The reality is, for the average person who's getting little to no daily exercise, anything is better than nothing. You can even benefit from doing 10 minutes of daily walking or some other low-intensity exercise," says Walter Thompson, a professor of exercise science at Georgia State University.

Increasing your physical activity by a few minutes a day can help — such as walking up a flight of stairs, instead of taking the elevator.

But will this give you all the benefits of regular exercise? Will the weight shed from your body? "Well, no, but you will start to get some benefits, and that's the point," says Thompson.

If you are not in the fat burning zone, you are not going to lose weight.

False. When heart rate monitors became popular, the concept of the "fat burning zone" emerged — claiming that if you work out at a low to moderate intensity, your body burns more fat than at a higher intensity. (To this day, most cardiovascular fitness equipment charts your "fat burning" heart rate zone for you.) As pleasant as this idea might be, it's a myth.

Yes, you do burn a higher percentage of calories from fat when your body is at a lower heart rate. "The problem is, that's only half the equation. You may be burning more fat on a percentage basis, but you will be burning fewer calories overall, and the key to weight loss is caloric expenditure, not fat burning," says James Churilla, an exercise physiologist at Broward General Medical Center. "Given the same duration, working out at a higher intensity burns more calories (and fat), even though the percentage of fat burned may be lower."

Here's an example to help illustrate this point: 30 minutes of walking burns about 200 calories (70 percent from fat or about 140 fat calories), whereas 30 minutes of jogging burns 300 calories (50 percent from fat or about 150 fat calories).

So you see, the higher intensity jogging burns more calories AND fat.

Charles Stuart Platkin is a syndicated health, nutrition and fitness columnist.