Abstract
BACKGROUND: Exercise for weight loss and maladaptive exercise (exercise that results in negative consequences or interference with daily life) are common behaviors among youth and are associated with increased risk of disordered eating symptoms. The current study clarifies processes that influence exercise-related risk in adolescence and young adulthood, including the frequency with which young people transition between engaging in exercise for weight loss and experiencing negative consequences of this behavior. METHOD: Participants from the Avon Longitudinal Study of Parents and Children (ALSPAC) reported on eating disorder cognitions at age 14, and exercise behavior at ages 14, 16, 18, and 24 years old. Analyses examined rates of transition between the categories of 'No Exercise for Weight Loss', 'Exercise for Weight Loss', and 'Maladaptive Exercise' over time, identified overall trends in endorsement of exercise for weight loss and maladaptive exercise, and clarified predictors of these behaviors. RESULTS: Endorsement of exercise for weight loss and maladaptive exercise increased over time in both males and females. Those in the 'Exercise for Weight Loss' category were more likely than those in the 'No Exercise for Weight Loss Category' to transition to 'Maladaptive Exercise' over time. Body mass index (Age 13) and fear of weight gain (Age 14) were consistent predictors of maladaptive exercise across sex. CONCLUSIONS: Results support re-framing motivations for exercise in youth away from weight loss at a population level and targeting reductions in fear of weight gain for high-risk individuals.