 Taylor, Brožek, and Henschel from the Minnesota Laboratory of Physiological Hygiene traveled to the various CPS units to interview the potential candidates and administer physical and psychological tests to the volunteers.36 men were ultimately selected who demonstrated evidence of the required mental and physical health, the ability to get along reasonably well within a group while enduring deprivation and hardship, and sufficient commitment to the relief and rehabilitation objectives of the investigation to complete the study.The subjects were all white males, with ages ranging from 22 to 33 years old.