OKLAHOMA CITY —
Monica keeps trim and thin by dieting alone. She jokingly says that she can’t eat more than a sandwich without gaining weight. She’s happy with the way she looks and feels now. But how about when she’s 75?
There is a thin line between being trim and being frail, a common problem among older adults. Basically, frailty is a combination of osteopenia (loss of bone density) and sarcopenia (loss of muscle mass). Everyone is vulnerable, but the risk can be greatly reduced if you take action early in life to build and maintain strong bones and muscles.
Around the time of menopause, when hormone levels change, women become acutely aware of bone density and the possible development of osteoporosis. Osteopenia involves loss of bone mineral density that is greater than normal but not enough to qualify for osteoporosis. For many women, it is a precursor.
But loss of bone density is not limited to the menopausal and post-menopausal periods. Peak bone mass and size actually occur as early as age 20 in women. Bone remodeling — with removal of old bone and replacement with new bone — occurs throughout life, and even by age 30, the balance seems to be tilted toward loss.
A similar process occurs with muscles. Even persons who exercise regularly experience some loss of muscle mass with the passing years. Those who are sedentary may lose three to five percent of muscle mass each decade after 30 with dramatically faster loss around age 75.
The time to take action is not when you see a frail rather than a thin woman in the mirror, but rather in youth when you have a good chance of keeping your bones and muscles strong.
At all stages of life, but particularly during youth, the best thing you can do is to follow a physically active lifestyle while eating a diet that will keep your bones and muscles strong.
To build strong bones, weight-bearing exercise has long been recommended. These activities include dancing, aerobics, running, jogging and walking.
For muscles, resistance training is required. This means work with hand weights, machines or using your own body for resistance such as with pushups or pullups.Studies have found resistance training effective even for women and men in their 80s and 90s.
To head off frailty, should you concentrate on weight-bearing or weight-lifting exercise? The answer is: both. And there is probably a strong connection between the two. According to some research, bone strength and mass are influenced more by muscle forces than by either hormones or heredity.
It’s never too late to start, but the ideal is to begin in youth when you have peak mass and continue throughout life. One study found that older women who had been active throughout life had greater bone mineral density in the spine, hip, forearm and total body.
The other important factor is diet. Strong bones depend on an adequate supply of calcium, not only in later life when bone loss becomes evident but also in youth to build a strong reserve. Vitamin D, though, is crucial for the absorption of calcium. And a deficiency of either vitamin D or calcium can speed bone loss.
Vitamin D is more difficult to obtain from food, and deficiencies are common, particularly among older persons who are less able to synthesize vitamin D from sunlight.
Strong muscles require adequate protein along with a balanced diet that includes fruits, vegetables and fiber. In response to a protein deficiency, the body takes amino acids (the building blocks of protein) from muscle cells. And the result is muscle wasting.
Adolescent and adult women generally require about 46 grams of protein a day, but surveys indicate that 7.7 percent of adolescents and 8.0 percent of adult women do not get that much.
Women like Monica who practice constant dieting are highly likely to develop a deficit. Nutritionists often advise weight watchers to try to get a little protein with every meal. It is found in a variety of foods — meat, fish, beans, nuts, eggs, dairy products and even vegetables.
A study of kidney disease patients on a low-protein diet found that those doing resistance training for three days a week had an average increase in muscle fiber of 32 percent. Control subjects having no exercise lost an average of three percent of body weight.
Diet is important. But regular exercise, weight-lifting as well as weight-bearing, is the key to avoiding the inevitable loss of muscle mass and strength that comes with advancing age.
Rupp is care coordinator for Long Term Care Authority of Enid Aging Services. Contact her at 237-2236.