Definitions and performance standards of physical fitness vary. However, most experts agree that the five basic components of fitness are:
1. Cardiorespiratory or Aerobic Endurance The ability to do moderately strenuous activity over a period of time. It reflects how well your heart and lungs work together to supply oxygen to your body during exertion and exercise. Also called aerobic fitness.
2. Muscular Endurance The ability to hold a particular position for a sustained period of time or repeat a movement many times. This could be the capability required to hold a two-pound weight above your head for five minutes or the effort required to lift that weight 20 consecutive times.
3. Muscular Strength The ability to exert maximum force, such as lifting the heaviest weight you can budge, one time. It is possible to have muscular strength in one area, say your arms, while lacking strength in another area such as your legs.
4. Flexibility The ability to move a joint through its full range of motion; the elasticity of the muscle. This is how limber or supple you are.
5. Body Composition The proportion of fat in your body compared to your bone and muscle. It does not refer to your weight in pounds or your figure.
