Understanding low adherence to an exercise program for adolescents with obesity: the HEARTY trial

Summary Introduction Despite efforts to improve adherence to physical activity interventions in youth with obesity, low adherence and attrition remain areas of great concern. Objective The study was designed to determine which physiological and/or psychological factors predicted low adherence in adolescents with obesity enrolled in a 6‐month exercise intervention study aimed to improve body composition. Methods Three hundred four adolescents with obesity aged 14–18 years who volunteered for the HEARTY (Healthy Eating Aerobic and Resistance Training in Youth) randomized controlled trial completed physiological (body mass index, waist circumference, per cent body fat, resting metabolic rate and aerobic fitness) and psychological (body image, mood, self‐esteem and self‐efficacy) measures. Results One hundred forty‐one out of 228 (62%) randomized to exercise groups had low adherence (completed