A method of promoting secretion of a growth hormone includes the step of applying a thermal stimulus to specific sites on a body surface of the subject. The step of applying the thermal stimulus includes the steps of placing two or more guide elements made of two different kinds of metals respectively on at least two different sites of the specific sites, and controlling a temperature of the guide elements to be a range from 40 to 50±5° C., thereby applying the thermal stimulus to the specific sites according to a thermal stimulus pattern so as to increase a rate of blood flow in the subject by 60% or more by the application of thermal stimulus.