Approximately 46 percent (21 million) of older women in the United States have low bone mass, a condition that increases the risk of fracture, disability, and death, but may also be reversible. Exercise is recommended to maintain bone health in women, but the benefits of exercise may be limited by low levels of sex hormones after menopause.
A new R01 (a type of research project funded by the National Institutes of Health) study, “DHEA Augmentation of Musculoskeletal Adaptations to Exercise in Older Women,” led by CU College of Nursing Associate Professor Kathy Jankowski, PhD, FACSM, will attempt to show whether dehydroepiandrosterone (DHEA) will provide estrogenic and androgenic hormonal responses that will enhance the benefits of exercise on bone and muscle in postmenopausal women.
“This research has high impact and importance for women, who have a longer life expectancy than men, and are more prone to health issues arising from lower bone mineral density,” Jankowski says. The project is federally funded for a five-year period of study at $600,000 per year.
Exercise is recommended for postmenopausal women to maintain or increase areal bone mineral density, to improve muscular fitness and balance, and ultimately to prevent fractures. During exercise, joint-reaction and ground-reaction forces contribute to strain signals that are transduced via a mechanostat to osteocytes, causing region-specific adaptations in bone tissue.
However, age-related declines in anabolic adrenal, gonadal, and somatotropic hormones may blunt this and other musculoskeletal adaptations. DHEA is the major source of estrogen and testosterone in postmenopausal women, but adrenal DHEA production declines with age.
Jankowski’s research project proposes that DHEA therapy, by providing androgenic and estrogenic hormonal support, will augment the effects of bone-loading exercise on areal bone mineral density and fat free mass in women with low…