High-impact exercise strengthens 
older bones

By Maxine Frith of the Press Association; London, PA 

Middle-aged people should take up energetic activities such as step aerobics rather than gentle exercise like walking to avoid bone diseases in later life, according to a new study.

Low and moderate impact exercise has no effect on reducing the risk of fractures or bone loss, which can lead to the crippling disease osteoporosis. Vigorous, high-impact exercise such as tennis, badminton and step aerobics  can reduce the risk of hip fractures by 33 percent in men and by 12 percent  in women, a study in the British Medical Journal has found.

Women who take regular, high-impact exercise have the bone density of someone four years' younger. 

Researchers from Cambridge University interviewed more than 5000 men and women aged 45 to 74 for the study. The researchers conducted an ultrasound scan on the heels of all the people in the study to give an indication of their bone density. (Low bone density in the heel carries a higher risk of hip fractures and bone loss in later life which can cause osteoporosis.)

Men who took more than two hours of high impact exercise a week and women  who did any vigorous exercise had much higher bone density than those who took no similar activity.

The researchers said the benefits appeared to come from exercise that had  elements of airborne projection and impact, such as leaping around in  badminton and tennis, or jumping up and down during step aerobics.

But report author Nicholas Wareham, of Cambridge University, warned that "Prescribing high-impact activities for older people with established  osteoporosis would probably do more harm than good."