(With excerpts from “But My Doctor Never Told Me That!”: Secrets for Creating Lifelong Health )
Judith L. Boice N.D., L.Ac.
Opening a sleepy eye and stepping on the scale in the morning tells you how much you weigh but provides no information about the body tissues that contribute to that total weight. Some people’s weight falls in the “normal” range, yet they have elevated body fat levels. Others may exceed normal weight levels yet have normal body fat levels. The scale simply cannot detect the difference between muscle, bone, and fat.
Many people in this culture are slaves to their scales. Women’s magazines make fortunes peddling the latest quick weight loss diets. These programs do work . . . for a short time. Usually within a few weeks of stopping the grapefruit- and-marshmallow-only regime, the frustrated dieter tips the scales at an even higher weight than before she started the diet. Unfortunately, during these severe regimens the dieter loses more muscle than fat. Crash dieting catapults the body into “survival” mode. The metabolic rate slows to a crawl to protect the body from starvation. In this crisis situation, the body shifts from burning fat to consuming muscle for calories and protein. When the hapless dieter reaches her target weight, she has slowed her body metabolism to that of a hibernating reptile and reduced muscle tissue in her body. When she returns to her normal diet, her slowed metabolism ensures that her body quickly will replace its lost store of fat plus a little buffer, just in case she encounters “hard times” (another diet) in the future. She also may struggle to maintain even this increased weight because she now has less muscle to burn calories.
What this means for you: Increasing your metabolic rate with aerobic and strength building exercise is a better weight loss strategy than focusing on diet alone.
Strength-building exercise increases the muscles’ ability to exert force against resistance, e.g. lifting an object or throwing a ball. Over time, strength building exercise increases muscle size. Because men have higher testosterone levels, they develop larger muscles more quickly. Women, in contrast, increase muscle strength by 44 percent before their muscles increase in size. For women, strong muscles do not necessarily mean large muscles
When askied the single most important factor to siow aging in the body, researcher William Evans immediately responded, “Lift weights.” Each year after age 35 our bodies gain a pound of fat and lose 1/2 pound of muscle. Our scales measure the increase in fat but cannot detect the loss of muscle, which affects both our body shape and our metabolism.
What this means for you: Weight lifting can reverse the effects of aging by building muscle mass and increasing the metabolic rate.
At rest, one pound of fat burns approximately two calories a day. In comparison, a pound of muscle burns 34 calories a day! Losing muscle and gaining fat means that our bodies burn fewer calories per day. As our metabolism slows, we convert more of our food calories into fat. We enter a vicious cycle – more fat means fewer calories burned means more food calories converted into fat.. . no wonder we have more trouble maintaining a normal weight after age 35!
Strength building exercise can prevent that 1/2 pound per year muscle loss. You are never too old to begin. Even elderly nursing home residents (ages 86-96) significantly benefited from a weight-training program.1 With gradual training, you can even increase muscle mass over time.
Research in the early 1990s demonstrated that exercise programs combining aerobic and resistance exercise catalyzed three times more fat loss than aerobic exercise alone. Knowing how many more calories muscles burn at rest, you can understand why resistance exercises, e.g. weight lifting, would increase fat loss.2
| Calories burned at rest
Amount lost after age 35
Amount gained after age 35
| 34 calories per
pound per day
1/2 pound per
| 2 calories per
pound per day
1 pound per
1 Fiatarone, M.A. et al. “Exercise training and nutritional supplementation for physical failty in very elderly people,” N Engl J Med 300, no. 25 (June 1994): 1769-75
2 Kase, Lori Miller. “Lift weight to lose it,” Vogue 181, no.4 (April 1991): 222(2).