BASIC PRINCIPLES OF EXERCISE, BODY COMPOSITION, AND TERMINOLOGY USED IN THE REPORT ARE EXPLAINED. A REVIEW OF LITERATURE CONCERNING EXERCISE AND PHYSICAL FITNESS CONSIDERS ASPECTS OF CARDIORESPIRATORY FITNESS, SUCH AS AGE, INTENSITY OF TRAINING, AND MODES OF TRAINING; ENVIRONMENTAL FACTORS (HEAT, ALTITUDE); BODY COMPOSITION AND CHANGES RESULTING FROM EXERCISE; MUSCLE FLEXIBILITY; STRENGTH AND ENDURANCE; AND THE IMPORTANCE OF WARM-UP AND COOL-DOWN PERIODS. THE NEED FOR MEDICAL SCREENING AND FITNESS EVALUATION BEFORE BEGINNING AN EXERCISE PROGRAM IS STRESSED, AND GUIDELINES FOR CONDUCTING SUCH TESTS ARE OUTLINED. FACTORS WHICH SHOULD BE CONSIDERED IN MAKING AN EXERCISE PRESCRIPTION, INDIVIDUAL GOALS OF THE PROGRAM, INITIAL LEVEL AND TYPE OF ACTIVITY, AND MAINTENANCE PROGRAMS ARE DISCUSSED. SPECIFIC EXERCISES ARE DIAGRAMMED AND DESCRIBED. STRUCTURE, ORGANIZATION, EVALUATION, AND SUPERVISION OF A FITNESS PROGRAM, AS WELL AS MOTIVATION FACTORS, ARE CONSIDERED. REFERENCES ARE PROVIDED FOR EACH CHAPTER. SEE ALSO NCJ NUMBERS 44118, 44149, 44815, AND 44817.