Improvements in Physical Fitness Associated with a Course of U. S. Navy Underwater Trainees, with and without Dietary Supplements

Abstract An evaluation of the U. S. Navy's program of training for underwater swimmers, at Key West, during one typical course of six weeks, shows muscular, cardiovascular, and fat reduction improvements. The program of intensive physical conditioning, both in and out of the water, totaled about five hours of vigorous exercise per day, five days per week. In addition to swimming, the 30 men took land calisthenics drills, ran on an outdoor track, carried scuba packs weighing about 60 lbs., and took many test exercises to virtual exhaustion. Improvements equalled those obtained in wartime university programs but appear to be proportional to time spent, and were better than peacetime programs. Improvements in the cardiovascular area are considered handicapped and were probably hampered by insufficient sleep and the fatigue which accumulated during the course of the experiment. The time was considered inadequate to make the fullest cardiovascular adjustments. Fatigue showed especially in quiet cardiovascular ...