Background: Identifying the risk factors associated with a bone stress injury (BSI), including stress reactions and stress fractures, may aid in targeting those at increased risk and in formulating prevention guidelines for exercising girls and women. Purpose: To evaluate the effect of single or combined risk factors as defined by the female athlete triad—a syndrome involving 3 interrelated spectrums consisting of energy availability, menstrual function, and bone mass—with the incidence of BSIs in a multicenter prospective sample of 4 cohorts of physically active girls and women. Study Design: Cohort study; Level of evidence, 3. Methods: At baseline, participants’ (N = 259; mean age, 18.1 ± 0.3 years) anthropometric characteristics, eating attitudes and behaviors, menstrual function, sports participation or exercise activity, and pathological weight control behaviors were assessed. Dual-energy x-ray absorptiometry (DXA) measured the bone mass of the whole body, total hip, femoral neck, lumbar spine, and body composition. Participants were followed prospectively for the occurrence of injuries; those injuries confirmed by a physician were recorded. Results: Twenty-eight participants (10.8%) incurred a BSI. Forty-six percent of those who had ≥12 h/wk of purposeful exercise, a bone mineral density (BMD) Z score <–1.0, and who exhibited 3 to 4 of the following: BMI <21.0 kg/m ² , oligo- or amenorrhea, elevated dietary restraint, and/or participation in a leanness sport exercise/activity at baseline, incurred a BSI during the prospective study period. Single factors significantly ( P < .05) associated with the development of a BSI included ≥12 h/wk of purposeful exercise (14.7%), BMI <21.0 kg/m ² (15.3%), and low bone mass (BMD Z score <–1.0; 21.0%). The strongest 2- and 3-variable combined risk factors were low BMD ( Z score <–1.0) + ≥12 h/wk of exercise, with 29.7% incurring a BSI (odds ratio [OR], 5.1; 95% CI, 2.2-12.1), and ≥12 h/wk of exercise + leanness sport/activity + dietary restraint, with 46.2% incurring a BSI (OR, 8.7; 95% CI, 2.7-28.3). Conclusion: In the sample, which included female adolescents and young adults participating in competitive or recreational exercise activities, the risk of BSIs increased from approximately 15% to 20% for significant single risk factors to 30% to 50% for significant combined female athlete triad–related risk factor variables. These data support the notion that the cumulative risk for BSIs increases as the number of Triad-related risk factors accumulates.

Were assessed using the Eating Disorder Examination Questionnaire (EDE-Q). Menstrual and sports participation history were evaluated using an interviewer-assisted, self-report questionnaire. Bone mineral density (BMD) of the spine (L1-L4), total hip, and total body were measured by dual-energy x-ray absorptiometry. The −2 and −1 BMD age-matched, gender-specific z-score cutoffs were used to categorize girls as having low bone mass for age. Results: Among the female runners, 11.8% and 28% met the −2 and −1 BMD z-score cutoffs, respectively, whereas 25.8% reported menstrual irregularity (MI). Total hip BMD, lumbar spine BMD, and lumbar spine BMD z-score were significantly lower in runners with MI after adjusting for body mass index (BMI) and lean tissue mass. Runners that participated in five or more compared with three seasons of endurance running exhibited a significantly lower total body and lumbar spine BMD z-score after adjusting for BMI, lean tissue mass, and number of menstrual cycles in the past year. Multiple regression analysis indicated that MI, participation in five or more seasons of endurance running, BMI, and lean tissue mass were independent predictors of low BMD. Conclusion: Female adolescent endurance runners may represent a population with an increased risk of low bone mass. Future studies are necessary to further understand the factors contributing to low bone mass in young runners and to identify behavioral strategies that will promote optimal bone mineral accumulation during the adolescent years....

Background: Because disordered eating (DE) has been related to menstrual irregularity (MI) and low bone mineral density (BMD) in some studies of female athletes but not in others, it seems beneficial to assess the DE attitudes and behaviors most associated with these conditions. Objective: We aimed to determine the relation between Eating Disorder Examination Questionnaire (EDE-Q) subscale scores, pathologic behaviors, MI, and low BMD in adolescent female runners. Design: Participants were 93 female competitive cross-country runners 13–18 y old. The EDE-Q, composed of subscales for weight concern, shape concern, eating concern, and dietary restraint, was used to assess DE. Menstrual history was determined by using a questionnaire derived from a medical history form administered before participation in high school athletics. The International Society for Clinical Densitometry and the World Health Organization criterion of ≤ −2 or ≤ −1 SD, respectively, was used to categorize runners as having low BMD. Results: Runners with elevated restraint had a significantly (P < 0.001) greater incidence of low BMD than did runners with elevated weight and shape concern. After adjustment for possible confounding variables (including menstrual history), lumbar spine BMD, bone mineral content, and BMD z score values were lowest in runners with elevated restraint. In addition, total-body BMD and total-body BMD z scores were significantly (P < 0.05) lower in runners with elevated restraint than in those with elevated weight or shape concern. Elevated EDE-Q scores for weight or shape concern, pathologic behaviors, or any combination of the 3 without concurrent dietary restraint were not significantly associated with low bone mass. Conclusion: These findings suggest that, in adolescent female runners, dietary restraint may be the DE behavior most associated with negative bone health effects.

Background: Female adolescent runners have an elevated prevalence of low bone mass for agemdashan outcome that may be partially due to inadequate energy intake.

We aimed to evaluate patterns of bone mineral accrual among a cross-sectional sample of female adolescent runners and girls participating in a nonendurance running sport. One-hundred and eighty-three interscholastic competitive female athletes (age 16.0 ± 0.1 years), 93 endurance runners and 90 nonrunners, completed a menstrual and sports history questionnaire, had their height and weight measured, and underwent a dual-energy X-ray absorptiometry scan for the measurements of body composition and bone mass. For the majority of analyses, the girls were separated into four groups according to their age (13 to 14 years, 15 years, 16 years, and 17 to 18 years). Runners' height, weight, body mass index (BMI), percent body fat, lean tissue mass, number of menstrual cycles in the past year, and months of participation in a non-lean-build/variable-impact-loading sport were significantly lower than mean values for nonrunners. Although bone mass rose at all sites in the nonrunners between the ages of 13 to 14 years and 17 to 18 years, no such increase was noted in the runners. Runners compared with nonrunners exhibited significantly lower body weight and height-adjusted total body and lumbar spine bone mineral content (BMC) values and lower bone mineral density (BMD) Z-score values among the older (16 years and/or 17 to 18 years) but not younger (13 to 14 years and/or 15 years) age groups. These findings suggest that the runners, in contrast to the nonrunners, exhibited a suppressed bone mineral accrual pattern, which supports the notion that female adolescent endurance runners may be at risk for inadequate bone mass gains and thus a low peak BMD. © 2010 American Society for Bone and Mineral Research

9 ± 0.2 yr) at two time points, approximately 3 yr apart, to assess bone mass status and identify variables associated with bone mass change. Methods: Follow-up measures included a questionnaire to assess menstrual status, training, and sports participation history, height and weight, and a dual-energy x-ray absorptiometry scan to assess total body, total hip, and lumbar spine BMD, bone mineral content (BMC), BMD z-score, and body composition. We used −1 and −2 BMD z-score cutoffs to categorize runners with low bone mass. Results: Eighty-seven percent of girls with low BMD at baseline had low BMD at the follow-up. Girls with low compared with normal baseline BMD had lower follow-up adjusted total body (2220.4 ± 65.8 vs 2793.1 ± 68.2 g, P < 0.001), total hip (27.0 ± 1 vs 33.9 ± 1.0 g, P < 0.05), and lumbar spine (47.8 ± 2.0 vs 66.3 ± 2.2 g, P < 0.001) BMC values. Variables related to 3-yr training volume, menstrual function, age, developmental stage, and change in body mass explained 29%-54% of the variability in BMC change. Conclusions: The majority of adolescent runners with low BMD at baseline had low BMD after a 3-yr follow-up. Our observations suggest that "catch-up" accrual may be difficult and, thus, emphasize the importance of gaining adequate bone mineral during the early adolescent years....