Maintaining Muscle Strength May Counteract Postmenopausal Bone Loss

Sirola J, Rikkonen T, Tuppurainen M, Honkanen R, Jurvelin JS, Kroger H. Maintenance of muscle strength may counteract weight-loss-related postmenopausal bone loss-a population-based approach. Osteoporos Int. 2006 Feb 21.

Researchers writing in the medical journal Osteoporosis International say that maintaining muscle strength may counteract postmenopausal bone loss related to weight loss and that exercise that improves muscle strength may be encouraged for postmenopausal women with weight loss intentions for other health reasons.

From the study abstract:
INTRODUCTION: “Weight loss significantly increases postmenopausal bone loss, but the effects of muscle strength change on weight-loss-associated bone loss remain unclear. The study population, 587 peri- and postmenopausal women, was a random sample of the original Osteoporosis Risk Factor and Prevention Study (OSTPRE) study cohort in Kuopio, Finland.

Bone mineral density (BMD) at the lumbar spine (LS) and femoral neck (FN) was measured with dual x-ray absorptiometry, and grip strength was measured with a pneumatic squeeze dynamometer at baseline in 1989-1991 and at the 10-year follow-up in 1999-2001.

METHODS: Women were divided into three groups according to change in age-grouped grip-strength quartile in both of the measurements: “decreased”, “maintained” , and “improved”.

In addition, the study sample was divided into two groups according to weight change during the follow-up: weight losers and weight gainers.

RESULTS: There were no differences in the change status of grip (muscle) strength between the weight loss and weight gain groups.

Women losing weight during the follow-up and within the improved grip-strength-change group had a significantly lower bone loss rate compared with those in the maintained and decreased grip-strength-change groups.

This was in contrast to women who gained weight during the follow-up (not significant between any grip-strength-change groups). Furthermore, women who lost body weight and were in the improved grip-strength-change group had a bone loss rate comparable with that of the women who gained body weight (not significant).

CONCLUSION: The present study suggests that maintaining muscle strength may counteract postmenopausal bone loss related to weight loss. Accordingly, exercise that improves muscle strength may be encouraged for postmenopausal women with weight loss intentions for other health reasons.”