Objectives: Determine whether the prevalence of eating disorder classifications (i.e., clinical eating disorder, subclinical eating disorder, and asymptomatic) and pathogenic weight control behaviors (e.g., bingeing, vomiting) change over a five-month sport season.Design: Longitudinal study.Methods: Female collegiate gymnasts and swimmers (N=325) completed the Questionnaire for Eating Disorder Diagnoses as well as six items from the Bulimia Test-Revised at Time 1 (two weeks into the beginning of their athletic season) and Time 2 (final two weeks of the athletic season); data collections were separated by five months.Results: Over the course of the season, 90% of the athletes (18 out of 20) retained a clinical eating disorder diagnosis or moved to the subclinical classification. Of the 83 subclinical athletes at Time 1, 37.3% persisted with that classification and 10.8% developed a clinical eating disorder; the remainder became asymptomatic/healthy eaters by Time 2. The majority of Time 1 asymptomatic athletes (92.3%) remained so at Time 2. Exercise and dieting/fasting were the most frequent forms of weight control behaviors, though each was used less frequently at Time 2 (exercise=35.4%; dieting=9.2%) than at Time 1 (exercise=42.5%; dieting=12.3%).Conclusions: Eating disorder classifications, particularly clinical and subclinical, remain stable across a competitive season, supporting the need for early detection and purposeful intervention. Athletes engage in weight control behaviors that may be reinforced in the sport environment (e.g., supplemental exercise), making identification more challenging for sports medicine professionals. [ABSTRACT FROM AUTHOR]