The study evaluated the effects of the use of interval running training techniques instead of the traditional physical training methods employed at the U.S. Marine Corps Officer Candidate School. One platoon was trained by use of interval running techniques while a control platoon employed the continuous running method. Both methods improved the candidates' ability to run a distance of three miles, but there was no significant difference between the results of the two programs. It was suggested that the physical activity required in the overall program may have obscured the effects of that portion of it. Further studies employing different programs are indicated. (Authors/PT)