| Exercise | Planned, structured, and repetitive movement to improve or maintain one or more components of physical fitness |
| Intensity | Absolute intensity is the amount of energy used by the body per minute of activity, objectively measured as a metabolic equivalent, or MET; 1 MET = the amount of energy used in a resting state, like sitting or sleeping |
| Relative intensity is the level of effort required to do an activity, as rated by the individual doing the activity; on a 10-point scale, sitting = 0 and working as hard as possible = 10 |
| Light intensity (e.g., casual walking, light housework, stretching) | < 3 METs |
| Moderate intensity (e.g., brisk walking, water aerobics, ballroom dancing, gardening) | 3 to 5.9 METs, or the individual will breathe harder with a faster heart beat; the individual should be able to talk but not sing; on a 10-point scale, a moderate-intensity activity would be rated as 5 to 6 |
| Vigorous intensity (e.g., jogging or running, aerobic dancing, heavy gardening) | ≥ 6 METs, or the individual will not be able to say more than a few words without pausing for a breath |
| Physical activity | Body movement that is produced by the contraction of skeletal muscles and that increases energy expenditure |
| Aerobic/endurance exercise (e.g., walking, stationary cycling, aquatic exercise) | Exercise in which the body's large muscles move in a rhythmic manner for sustained periods |
| Balance training (e.g., backward, sideways, heel, or toe walking; tai chi) | A combination of activities designed to increase the individual's lower body strength and reduce the likelihood of falling |
| Flexibility exercise (e.g., stretching hamstring, calves, or triceps) | Activities designed to preserve or extend range of motion around a joint |
| Resistance/strength exercise (e.g., exercises using resistance bands, weight machines, handheld weights; digging, lifting, and carrying as part of gardening; carrying groceries) | Exercise that causes muscles to work or hold against an applied force or weight |
| Physical function | The capacity to carry out the physical activities of daily living; physical function reflects motor function and control, physical fitness, and habitual physical activity |
| Sedentary behavior | Activity that involves little or no movement or activities that are considered posture (e.g., sitting), having an energy expenditure of ≤ 1.5 METs17 |
