Then came a grueling series of physical and psychological tests at the Lovelace Clinic and the Wright Aerospace Medical Laboratory. Carpenter was considered the most physically fit by his peers; he had the lowest body fat, scored highest on the treadmill and cycling tests, and was able to hold his breath the longest. This was despite the fact that he had smoked a pack of cigarettes a day since joining the Navy in 1943, and did not quit smoking until 1985.