The research included 50 healthy postmenopausal women, aged 58 to 75. During the two-year study, 27 women did back-strengthening exercises, while 23 women in a control group did not do the exercises.
The two groups had no difference in bone mineral density at the end of the two-year exercise period. However, the women in the control group were 2.7 times more likely to have vertebral compression at the end of 10 years.
The women who did the exercises had more back strength than the control group members -- even eight years after the exercise program ended. Those who did the exercises also had less bone density loss than those in the control group.
"Exercise requires more effort than taking a pill, so getting patients to comply with an exercise program is more difficult," concedes lead author Dr. Mehrsheed Sinaki, a Mayo Clinic physical medicine specialist.
Osteoporosis affects 8 million women and 2 million men in the United States, and is responsible for 1.5 million fractures each year.
The study was published in the June issue of BONE.
For details on exercise and prevention of osteoporosis, check the National Osteoporosis Foundation.