A conditioning process for the enhanced production of human growth hormone in a human has a first step of application of pressurized cooling to the limbs of a subject, who experiences a ramp-up exertion followed by a series of conditioning cycles, followed by a ramp-down cycle. The condition cycles include an interval of intense exertion followed by an interval of reduced exertion, and during ramp-up cycle, conditioning cycle, and ramp-down cycle, the pressure cooling to the limbs is set as a fraction of systolic blood pressure, with the fraction in the range 33% to 220%.
