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aerobics aer·o·bics (â-rō'bĭks)
A system of physical conditioning to enhance circulatory and respiratory efficiency that involves vigorous, sustained exercise, such as jogging, swimming, or cycling, thereby improving the body's use of oxygen.
A program of physical fitness that involves such exercise.
Note: The term aerobics usually refers to a specific kind of vigorous exercise, sometimes involving dance steps, that is set to music. Other forms of aerobic exercise include running, cycling, and swimming.