[Problem] To provide a living body improvement method with which vital function and/or cognitive function is improved by regularly inhaling, through the mouth or nose, air containing a high concentration of hydrogen using a portable electrolysis-type hydrogen generator. [Solution] In this living body improvement method, for example, air containing a high concentration of hydrogen is inhaled for a prescribed amount of time at least 5 times per day at intervals of approximately at least 15 minutes, and this inhalation is continued for approximately 4 weeks or more. An electrolysis-type hydrogen generator used in this method is portable, and comprises: a positive-negative electrode pair； a transparent or semi-transparent electrolytic cell into which the electrode pair is inserted and which is capable of storing water； a mixing unit that establishes a fluid connection between the electrolytic cell and a nozzle which enables oral or nasal inhalation while being gripped with one hand, and that has a fluid passage which takes in environment air； and an operation means which can be operated while the electrolysis-type hydrogen generator is gripped with one hand. A control board controls, through a single operation of the operation means, the supply and cutoff of power from a battery to the positive-negative electrodes.Le problème décrit par la présente invention est de fournir un procédé d'amélioration du corps vivant avec lequel la fonction vitale et/ou la fonction cognitive est améliorée par inspiration régulière, à travers la bouche ou le nez, de l'air contenant une concentration élevée d'hydrogène en utilisant un générateur portable d'hydrogène de type électrolyse. La solution selon l'invention porte sur un procédé d'amélioration du corps vivant, par exemple, de l'air contenant une concentration élevée d'hydrogène est inspiré sur une durée prescrite au moins 5 fois par jour par intervalles d'approximativement au moins 15 minutes, et cette inspiration est poursuivie dura
