The aging process is characterized by the gradual decrease in muscle mass, strength and power leading to a decline in physical functioning, increased frailty and disability. This age related loss of muscle mass and function has been termed sarcopenia. The mechanisms that underlie sarcopenia are only beginning to be elucidated. However, specific modes and intensities of physical activity can both act to preserve and also increase skeletal muscle mass, strength, power in healthy and functionally limited older individuals. This effect appears to be pervasive throughout the lifespan and there is evidence for similar responses in men and women. The focus of this chapter is on the role of exercise as a therapeutic intervention for the prevention and treatment of sarcopenia. This will be accomplished by (1) reviewing the epidemiology on physical activity and sarcopenia (2) summarizing the molecular mechanisms associated with sarcopenia and exercise, (3) discussing the efficacy of resistance and endurance exercise or multi-modal exercise, such as the combination of aerobic and resistance exercise for the management of sarcopenia.