Women: Weight Lost With Exercise Returns But Bone Density Doesn’t
The bad news is: the weight comes back, but the bone doesn't. That's the indication of a small study (23 people) of postmenopausal women who took part in a regular program of endurance exercise to encourage weight loss of about 9 to 11 pounds. That part worked great. The Los Angeles Times reports that the women women lost an average of 8.6 pounds of fat. But after 18 months — a year after they stopped exercising — they had gained back an average of 6.4 pounds, almost all of it fat. Yikes! The women were also tested for bone density at the beginning of the study as well as six and 18 months later. Almost 40 percent had osteoporosis at the beginning of the study. The researchers found that during the six months, the women also lost bone density in their lumbar spines and hips, and there was no significant bone recovery after they regained the weight. The newspaper reports that the authors suspect that the bone loss may have been prevented or reduced had women done exercise that increased bone density, such as strength training (non-impact cardiovascular exercise typically doesn't build bone mass). The authors also speculated about whether low bone mass in some overweight and obese people may be partially blamed on repeated diet-and-weight-gain cycles.