Aging is a natural process affected by the environment, genetics, lifestyle, and health, and is unique to each individual. To maintain independence and control requires an active and healthy lifestyle: exercise, healthy diet, intellectual activities, and a variety of social activities. Careful planning is required to maintain basic levels of functioning. Physical inactivity makes your body age faster, causing loss in bone strength, muscle strength, heart and lung fitness, and flexibility. Active living and physical activity improve posture and balance, self-esteem, and weight maintenance; lead to stronger muscles and bones; and contribute to relaxation and stress reduction.