Lifting Weights Makes Elderly People Stronger, Fitter

Arnold Schwarzenegger isn’t the only body builder pumping iron to stay strong and fit.

Medical researchers at the Tufts Research Center on Aging in Boston say that even people in their 80s and 90s can build muscle size and strength by lifting weights.

“Up to now, we’ve focused on the loss of bone, or osteoporosis, as a result of aging,” said Dr. Irwin Rosenberg, center director. “But the decline in muscle mass is even more evident, particularly in men.”

Rosenberg has coined the word “sacromalacia” to describe the age-related loss of muscle strength. Tufts scientists are investigating whether this condition can be slowed or even reversed with physical activity, and the results look promising.

An intensive exercise study on men between the ages of 60 and 70 shows that weightlifting exercises dramatically improve strength and mobility. The volunteers worked out on weightlifting machines to strengthen leg and knee muscle mass. The result was a 100% gain in muscle strength and a 25% gain in muscle size for the group over a 12-week period.

Even more dramatic were the results of an exercise study of frail elderly nursing-home residents aged 90 and over.

Starting with 10- to 15-pound weights, these seniors doubled their weightlifting ability at the end of an eight-week period--gaining more than 150% in muscle strength and 10% in muscle size.

“This proves that even sedentary, very inactive older people have the capacity to respond to exercise,” Rosenberg said.

The positive effects of exercise on weakened muscles is particularly important in helping older people remain vigorous and independent, Tufts scientists said.

“The loss of muscle strength severely limits mobility, leading to serious falls and disability,” said Dr. William Evans, chief of the physiology laboratory at the research center.

Evans said muscles are the biggest reserve of body protein--essential for energy and stress prevention. “The greater the muscle mass, the greater the ability of the body to adapt to stress, as in illness or surgery,” he said.

The Tufts center--officially known as the U.S. Department of Agriculture Human Nutrition Research Center--will do follow-up studies on the frail elderly to determine how diet, along with exercise, affects the aging process.

Research has shown that exercise, plus an adequate calcium intake, helps prevent osteoporosis. Studies also show a firm link between exercise and low-fat diets in the prevention of heart disease.

Scientists are just now focusing on the role of nutrition in exercise requirements for older people. Some of the questions they’re asking are: What changes in the diet help to prevent the decline in muscle mass? Do older people need more proteins and calories than younger people in rebuilding muscle strength?

“It’s clear that the loss of muscle mass with age is reversible,” Rosenberg said. “If older people continue to exercise from the ages of 40 to 80, they will lose only 10% to 15% of their body mass rather than a 30% loss if they’re inactive.”

Tufts scientists recommend exercises that increase mobility--such as walking, biking or working with small leg weights.

“Biologically, we probably won’t be able to extend life beyond 100 years,” Rosenberg said. “But we can strive for a higher level of performance and function for a vigorous, active late life.”