personnel have focused on the potential impact of training activities as well as actions taken by women to remain in compliance with body weight and body composition standards.

Jones (1996) presented the results of recent studies conducted with BCT units at Fort Leonard Wood, Missouri, which indicated that women in BCT had a 9 percent rate of stress fracture compared with 3.5 percent for the men (Canham et al., 1996). When risk of stress fracture is plotted against running speed (as an indication of fitness level), the curve is J shaped, with a small increase in risk for those with the fastest times and increasing risk for those with slower run times. Neither body fat nor BMI show strong associations with stress fracture risk in this population. Instead, women in the lowest and highest BMI groups appear to be at greatest risk, with a 2.5-fold increase in stress fracture risk among the highest BMI group. The most consistent observation among women in BCT is that lower fitness (and not fatness) levels tend to be associated with higher risk. No data were presented on the prevalence of menstrual problems secondary to training in this study.

Drake (1996) presented findings of an ongoing study he is conducting with Armstrong and colleagues to examine the factors associated with stress fracture and BMD in female midshipmen during their first year at the U.S. Naval Academy (average age at entry, 18.4 ± 0.9 years). Drake reported that U.S. Naval Academy stress injury rates for women are approximately 12 percent, compared with 3.4 percent for male midshipmen. The purpose of the ongoing study is to test two hypotheses: first, that low BMD is a significant risk factor for stress fractures, and second, that stress-induced oligomenorrhea or amenorrhea (and increased cortisol levels) might lead to lower BMD and increased risk of stress fractures. Results to date have shown that midshipmen are under high levels of stress, with cortisol concentrations at the high end of the normal range. Ten to 15 percent of first-year female midshipmen experience oligomenorrhea (defined as seven or fewer menses within a 12-mo period) during the first year. Five to 6 percent experienced amenorrhea (defined as two or fewer menses in a 12-mo period). Total body bone mineral content and tibial BMD increased over the first year regardless of menstrual status. However, hip BMD decreased with increasing menstrual dysfunction. Thus far, no association has been observed in the midshipmen between stress fracture incidence and menstrual status, but stress fractures are associated with a 6 percent decrease in BMD. Studies in this population of female military personnel are being continued.

Friedl (1996) reported that studies in young Army women have identified an association between increased prevalence of stress fractures and previous history of amenorrhea (which they defined as an absence of menses for greater than 6 months), as well as with smoking and previous family history of osteoporosis, while African American ethnic origin was found to be a negative risk factor (Friedl et al., 1992). These data, taken together, point to the potential role of menstrual status in influencing the impact of activity associated with military training on bone health.

Harold H. Sandstead (1996) summarized early reports from his laboratory and others demonstrating the importance of iron status in scholastic achievement and cognition of young children (Pollitt et al., 1982; Webb and Oski, 1973), and pilot work by Darnell and Sandstead (1991) indicating that iron repletion improved short-term memory in women. The rationale for

Front Matter (R1-R16)

Executive Summary (1-24)

1 Introduction (25-32)

2 Body Composition (33-60)

3 Physical Fitness Policies and Programs (61-86)

4 Weight Management (87-108)

5 Nutritional Concerns of Military Women (109-126)

6 Pregnancy and Lactation and Postpartum Return-To-Duty Fitness (127-156)

7 Conclusions and Recommendations (157-170)

Appendixes (171-172)

A Workshop Summary, Agenda, Participants, and Abstracts (173-252)

B Practices and Policies Tables (253-262)

C Military Occupational Specialty Classification Tables (263-280)

D Search Strategy for Literature Review (281-284)

E Civilian Inquiry Letter and Table of Responses (285-290)

F Abbreviations (291-294)

G Bibliography (295-334)

H Biographical Sketches (335-338)

Index (339-352)