Adolescence is a critical period for growth, maturation, and endocrine regulation, during which hormonal adaptations play a key role in physical development and long-term metabolic health. Physical exercise acts as an important physiological stimulus capable of modulating several endocrine pathways involved in energy balance, appetite regulation, and cardiometabolic function. This chapter discusses the influence of exercise on the endocrine system in children and adolescents, emphasizing its effects on metabolic control, body composition, and appetite-related hormones. Evidence indicates that aerobic, resistance, and combined exercise interventions improve insulin sensitivity, reduce cardiometabolic risk factors, and promote favorable hormonal responses, even in the absence of significant weight loss. Acute exercise transiently suppresses orexigenic signals and enhances satiety-related hormones without inducing compensatory increases in energy intake, particularly in adolescents with overweight or obesity. The chapter also addresses practical considerations for exercise prescription in this population, highlighting the importance of developmentally appropriate, individualized, and supportive approaches. Overall, physical exercise represents a key non-pharmacological strategy to support endocrine balance and healthy growth during adolescence.