Debunking the Myths: Exercise Effects on Weight Loss

from the book by Dr. Elizabeth Lee Vliet, MD: Women, Weight and Hormones: Are Your Hormones Making You Fat?
M. Evans and Co. New York

Exercise is one of the legs of your three-legged stool when it comes to losing body fat and excess pounds. Moving the body is a critical component in any weight-control program that is going to be effective in reaching your goals. Unfortunately, some of you have a number of misconceptions about weight and exercise, myths we heard at some point in our lives. Here are some of the more common ones I hear from patients every day.

Myth: Exercise increases your appetite. “ I can’t exercise, I’ll eat more if I work out.”

Fact: Exercise actually decreases your appetite if you are working out within your aerobic heart rate range. If you exercise at high intensity and overshoot your aerobic range, this means that you deplete your muscle and liver glycogen stores, which in turn will make you very hungry following a workout. But even with this effect, any slight increase in food intake from physical exercise is usually more than offset by two factors: (1) calories expended by the exercise itself, and (2) your increased metabolic rate for several hours after your workout is over.

Myth: In order for exercise to be effective, you must work out every day. “I don’t have time to exercise every day, so it won’t do me any good.”

Fact: Current studies have shown two key points here: (1) simply increasing your physical movement throughout the day, every day, will help your body burn more calories. For example, parking further from the store, taking stairs instead of elevators are two easy ways to achieve this step. (2) Exercising at your aerobic heart rate range for just three times a week for around 20 minutes each time will burn off a significant number of calories, plus stimulate your metabolism for several hours afterwards. Can’t you make 20 minutes, just three days a week, an important time commitment for YOU in the midst of all you do for others? Certainly, if you exercise longer–say, 45 minutes to an hour–you’ll burn even more calories, but even the 20-30 minutes does wonders!

Myth: Exercise must be really strenuous to achieve weight loss. “I hurt too much so I can’t do anything strenuous enough to do me any good.”

Fact: Actually, if you are overweight and out-of-shape, “really strenuous” exercise may be putting you into your anaerobic range and not helping as much toward your weight loss goals. Most of my patients were astounded at how quickly a low-intensity exercise like walking got their heart rate into the target range, and they were surprised when I said this was all I wanted them to do! If done regularly, three to five times a week, just brisk walking for 30 minutes at the time can burn up to 15 pounds a year. Not bad.

Myth: The more you sweat, the faster you lose weight. “I want to get my weight down quickly and lose all this water!”

Fact: Not only is there no benefit to excessive sweating, it may be dangerous, particularly if you are on blood pressure medications or diuretics or are out-of-shape. So don’t wear those “sauna suits” or excess clothes to increase sweating. You’ll just get dizzy, faint and light-headed and be more likely to give up!

Myth: Aerobic exercise is no better than any other form of exercise for weight loss. “I think I’ll just concentrate on more activity around the house.”

Fact: Whenever you have a sustained increase in your heart rate to the aerobic range for your age, you will speed up your metabolism due to the effects of the “exercise hormones” I described earlier. This effect on your metabolism also lasts 4 to 8 hours after you stop exercising, which means Therefore, additional calories will be burned off long after you finish working out. Non-aerobic exercise, like housework or gardening or weight-lifting, doesn’t have this metabolism-boosting effect, although these forms of exercise will improve muscle tone and strength.   Aerobic exercise like walking, swimming, roller-blading, cycling, or dancing are the “metabolism-boosters” you most need to help your body lose excess fat.

Myth: Women shouldn’t exercise during their periods. “Now that I hit perimenopause, I seem to have a period every two weeks, and I don’t feel like exercising then, so I get out of the habit.”

Fact: There is no medical reason why you shouldn’t exercise during your period. In fact, being physically active aerobically actually seems to help improve those bloating and crampy feelings. If your energy is lower, or the bleeding heavy, just take it a little slower than usual, or maybe do a little shorter work out. But keep moving! Besides the physical benefits, it also helps lift the low moods that tend to hit at this time of your cycle. If you are in perimenopause and bleeding more often, it’s time to talk with your gynecologist or women’s health specialist about some options to smooth out the hormonal turbulence and regulate your cycles better.

So, get out and MOVE that body!