Date of Award

5-22-2006

Degree Type

Dissertation

Degree Name

Ph.D.

Degree Program

Curriculum & Instruction

Department

Curriculum and Instruction

Major Professor

Speaker, Richard; Loftin, J. Mark

Second Advisor

Kontos, Anthony

Third Advisor

Eason, Bobby

Fourth Advisor

DeSanti, Roger

Abstract

The purpose of the study was to examine the relationship and comparisons of athletic amenorrhea and bone mineral density in adolescent, cross-country runners. Subjects: Twenty-eight female adolescent cross-country runners (Mean Age + SD = 15.0 + 1.3 years); consisting of seventeen eumenorrheics & eleven amenorrheics. Design: The design consisted of a sixmonth longitudinal design in which the subjects were measured before and after cross-country season for height, weight, and lean tissue (LT), body fat (BF), bone mineral content (BMC), and bone mineral density (BMD) using whole-body scan densitiometry with a Lunar Dual-energy X-ray Absorptiometer (DXA). Run performance, weekly training volumes, menstrual dysfunction, menarchal age, nutritional information, and stress fractures were reported by the subjects. Statistical analyses consisted of Pearson product-moment and partial correlations to examine the associations of the variables, paired t-tests to measure seasonal body composition changes, multivariate analysis (MANOVA & MANCOVA) to investigate the subgroup differences of variables, and simple linear regression to determine the best body composition predictor variable for BMD. Results: The eumenorrheic subgroup's BMD was significantly greater than the amenorrheic subgroup's BMD (F(1, 54) = 16.22, p<.05, partial h² =.231). The eumenorrheic subgroup's bodyweight (F(1, 54) = 7.65, p<.05, partial h² =.124), BF (F(1, 54) = 8.56, p<.05, partial h² =.137), and BMC (F(1, 54) = 8.52, p<.05, partial h² =.136) were significantly greater than the amenorrheic subgroup. There was also a significant seasonal increase in BMD (t(27) = -4.01, p <.05) for the overall group. Bodyweight was the body composition component that best predicted BMD (F(1, 26) = 46.434, p<.05, R² =.641). There were no significant subgroup differences with respect to run performance, stress fractures, and nutritional supplementation. Conclusions: Athletic amenorrhea was highly associated with lower levels of BMD in adolescent, cross-country runners. Athletic amenorrhea was also highly associated with lower levels of bodyweight, BF, and BMC in adolescent cross-country runners. Finally, cross-country running was highly associated with increased BMD in adolescent athletes. Implications: The long-term implication of the study is that subjects with lower levels of BMD may be at a greater risk of osteoporosis. Recommendations: Educate and instruct runners to utilize proper training methods so the healthful benefits of crosscountry running, as well as improved performance, are obtained.

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The University of New Orleans and its agents retain the non-exclusive license to archive and make accessible this dissertation or thesis in whole or in part in all forms of media, now or hereafter known. The author retains all other ownership rights to the copyright of the thesis or dissertation.

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