Cover Image


View/Hide Left Panel

immediate risk of stress fracture) and on the long-term risk of osteoporosis. In so doing, the subcommittee was asked to respond to the following five questions:

  1. Why is the incidence of stress fractures in military basic training greater for women than for men?
  2. What is the relationship of genetics and body composition to bone density and the incidence of stress fractures in women?
  3. What are the effects of diet, physical activity, contraceptive use, and other lifestyle factors (smoking and alcohol) on the accrual of peak bone mineral content, incidence of stress fractures, and development of osteoporosis in military women?
  4. How do caloric restriction and disordered eating patterns affect hormonal balance and the accrual and maintenance of peak bone mineral content?
  5. How can the military best ensure that the dietary intakes of active-duty military women in training and throughout their military careers do not contribute to an increased incidence of stress fractures and osteoporosis?

In considering the questions posed by the military (and as a follow-on activity to the subcommittee's earlier report, Assessing Readiness in Military Women [IOM, 1998]), the subcommittee consulted with a liaison panel comprising military researchers and health care personnel. The BCNH subcommittee met in executive session following the workshop to begin drafting their brief report. The subcommittee met in executive session for an additional writing session and to discuss their conclusions and recommendations on January 27, 1998. Based on information gathered from discussion with the workshop speakers, the military liaison panel and a brief review of the literature on bone metabolism and risk factors for bone health, the subcommittee prepared this brief report, Reducing Stress Fractures in Physically Active Military Women . The report was submitted to the sponsor in June, 1998.


Low initial fitness of recruits appears to be the principal factor in the development of stress fractures during basic training. The basic training period may be insufficient time to achieve the aerobic fitness level required and the musculoskeletal adaptations necessary to avoid injury.

Muscle mass, strength, and resistance to fatigue with cyclic loading (bone stress created by rapid or excessive incremental skeletal muscle contraction and loading forces) play a critical role in the development of stress fracture. The etiology of stress fracture is multifactorial, and bone mineral density is only one contributing factor. Genetics and body mass, specifically muscle mass, are also important determinants of stress fracture.

The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement