ABSTRACTThe associations among lower extremity functional performance and quality of life in obese youth are unknown. The aims of this study were to compare lower extremity strength, lower extremity functional performance, and health related quality of life between obese and healthy-weight youth and evaluate the relationships between lower extremity performance and health related quality of life in obese youth. Twenty obese and 20 age and sex matched healthy-weight youth were recruited. Peak torque of the major lower extremity muscles were measured. Functional performance was measured with single leg hop and single leg balance tests. The Paediatric Quality of Life questionnaire's physical and psychosocial health subscales were used. Paired t-tests and multiple regression analyses were performed. Obese youth demonstrated decreased peak torque in all muscles measured (P < 0.05), poorer functional performance (P < 0.05), and worse physical health related quality of life (P < 0.05) compared to healthy-weight youth. Lower extremity functional performance was associated with aspects of quality of life in the obese group (P = 0.002), but not in the healthy-weight group (P < 0.05). These results may assist in encouraging best practices in the promotion of exercise, physical activity, and quality of life in obese youth.