Exercise your way to stronger bones

Weight-bearing exercise is a must if you want to maintain strong bones. Stress or strain on bones stimulates the formation of new bone. Regardless of age, people who engage in regular weight-bearing exercise have higher bone density. And the converse is also true. A lengthy period of bed rest (or weightlessness, as in the case of astronauts) makes bones as brittle as icicles. Studies show that an exercise program can increase bone mass by five to ten percent -- and even more in those with low bone mass to begin with.

I recommend you start your exercise program by walking briskly 20 minutes, four times a week. Once you can do this comfortably, it's time to increase your pace. To do this, don't lengthen your stride; instead, increase the number of steps you take per minute. Work up to 30 to 60 minutes of exercise four or more times per week.

Although weight bearing exercise such as brisk walking and jogging is ideal for maintaining bone mass, more strenuous exercise may be needed to actually increase bone density. I recommend at least two sessions of weight training a week. Have an exercise instructor at your local gym show you how to start with small weights you can use at home.