The purpose of this study was to determine the effect of Aviation Officer's Candidate School (AOCS) on the aerobic and anaerobic fitness of the candidates. Thirty candidates were tested prior to and post-AOCS. Anaerobic measures included vertical jump and seated shot-put throw. A 1.5-mile run was used as an aerobic measure. Timed push-ups and sit-ups were used as overall strength and endurance measures. Body fat was assessed by OPNAV 6110.1 standards. Statistically significant increases were achieved in all areas, except for body fat and push-ups, which produced no significant changes.