Exercise

Exercise is a form of physical activity that is planned, structured, repetitive, and performed with the purpose of improving or maintaining one or more components of physical fitness. Unlike incidental movement during everyday life, exercise involves intentional organization of activity toward a fitness-related objective .^1,2

Exercise can be organized by variables such as type, intensity, duration, and frequency. Different forms place different demands on the body. Aerobic exercise emphasizes sustained activity involving large muscle groups, while resistance exercise involves muscles working against resistance. Other forms can emphasize qualities such as flexibility, balance, or neuromotor control .²

Exercise is a subset of physical activity, not a synonym for it. Physical activity includes bodily movement produced by skeletal muscles that results in energy expenditure, including movement during work, transportation, household tasks, recreation, and exercise. An activity can therefore count as physical activity without meeting the more specific definition of exercise .^1,2

Exercise should also be distinguished from physical fitness. Exercise describes an activity that a person performs, whereas physical fitness refers to measurable attributes such as cardiorespiratory fitness, muscular strength, or flexibility. Exercise is one means by which these attributes can be maintained or improved .¹