This study investigated physical and physiological changes of normal young adults, who are cadets of the Air Force Academy, have kept long-term physical activities and healthy behavior. The physical and physiological indices were the blood and body composition. Data were collected at the first year period, and then 4th year period from same group of cadets. The amounts of blood components were not changed, but variation among cadets was significantly reduced in the 4th grade period. The red blood cells(RBCs) were significantly reduced and the concentration of hemoglobin(HGB) were significantly increased. The body weight was significantly decreased in the 1st grade period since the body fat was rapidly decreased after the basic military drill, and then it was recovered with building up of the skeletal muscle in the 4th grade period. Asymmetry of the arms was decreased with the increased physical activities and usage of various equipments. The muscular endurance were significantly enhanced in the 4th grade period. The long-term physical activities and healthy behaviors may keep the physical strength through enhanced blood stream and oxygen supply by reduction of the RBCs and increased HGB concentration, and fat and muscle control.