Weight Lifting Combats the Effects of Aging

When it comes to fitness, investing in a set of weights might pay dividends just as big as a pair of walking or running shoes, researchers say. Indeed, research has shown that weight training (often called resistance training) can slow and even reverse the declines in strength, bone density and muscle mass that accompany aging.
The American College of Sports Medicine's fitness guidelines now recommend weight training for people over 50 in addition to aerobic activity and stretching. Muscle fibers shrink in number and in size as you grow older. They also become less responsive to messages from the central nervous system. Together, these factors contribute to decreases in strength, balance and coordination.
"Generally, sedentary people lose about 10 percent of their lean muscle mass for each decade after age 30," says Edward R. Laskowski, M.D., a physical medicine and rehabilitation specialist and co-director of the Sports Medicine Center at Mayo Clinic, Rochester, Minn.
"If you don't do anything to replace that, you're losing muscle and increasing fat," says Dr. Laskowski. "But, if you do strength training, you don't lose as much. It's like having a V-8 engine instead of a 4-cylinder. You have a bigger engine to burn more calories because it takes calories to keep that engine running."
Aerobic exercises like running, walking and bicycling strengthen your heart  also a muscle  by forcing it to adapt in a positive way. Similarly, weight training, done properly, challenges other muscles, forcing them to adapt to the stress and become stronger, according to Dr. Laskowski. Resistance training does more than just build muscle. It also can stimulate and strengthen bones  good news for those concerned about osteoporosis. Weight training also can help older people maintain their independence by keeping them strong enough to do routine tasks.
A University of Alabama at Birmingham study found that older women who lifted weights regularly during the study were able to carry bags of groceries with 36 percent less effort and to get up from their chairs with 40 percent less stress on their leg muscles than prior to the training. The 14 women in the study ranged in age from 60 to 77 and worked out for an hour, three times a week, for 16 weeks.
"No matter what your age, you can combat lean muscle loss by weight training," says Dr. Laskowski.
Copyright 1999, Mayo Foundation for Medical Education and Research.