Strength training may be good for older bones

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Strength training may be good for older bones

NEW YORK, Jan 16 (Reuters Health) - Strengthening exercises may help

healthy older men and women preserve their bone mass, the results of a

small study suggest.

Study participants who engaged in 6 months of resistance training showed

greater bone density in the hip area, as well as signs that their bone

metabolism had shifted toward generating more bone than was being lost.

Dr. R. and Randy W. Braith of the University of Florida in

Gainesville report the findings in the January issue of Medicine &

Science in Sports & Exercise.

The researchers had 62 healthy men and women between the ages of 60 and

83 participate in one of three groups: one that engaged in

high-intensity resistance training; one that went through low-intensity

training; and a " control " group that was instructed not to change their

lifestyle habits over the 6-month study.

The exercisers used resistance-training machines to perform various

strengthening exercises, such as leg presses, biceps curls and abdominal

crunches. All exercised under supervision, three times a week. Those in

the high-intensity group exercised against greater resistance than the

low-intensity exercisers did.

At the end of the study, the investigators found that the high-intensity

group made significant bone density gains in the area where thigh bone

meets the hip--an average 2% increase. No other areas they measured,

such as various regions of the spine, showed an increase in density.

However, the researchers note, low bone density in this thigh-meets-hip

area--called the femoral neck--is a major cause of fractures, disability

and death in the elderly.

And all of the exercisers had increases in blood markers of bone

metabolism that " favor increased bone mass, " according to the report.

It is possible, the authors speculate, that this metabolic change could

precede a boost in bone mass for the exercisers. Those in the

high-intensity group, which showed some evidence of increased bone

density, also had greater increases in these blood markers.

The researchers note that past studies of bone density and various

resistance-training regimens among older adults have yielded conflicting

results.

" It is important to know, " they point out, " not only what exercise

intensity is necessary to improve bone mineral density but also which

exercises have the greatest impact. "

In this study, they add, leg presses, overhead presses and certain back

exercises appeared to have the most impact on bone density.

SOURCE: Medicine & Science in Sports & Exercise 2002;34:17-23.