Athenaeus of Attalia distinguishes two types of exercise or training (γυμνασία) that are required at each stage of life: training of the body and training of the soul. He says that training of the body includes activities like physical exercises, eating, drinking, bathing and sleep. Training of the soul, on the other hand, consists of thinking, education, and emotional regulation (in other words, 'philosophy'). The notion of 'training of the soul' and the contrast between 'bodily' and 'psychic' exercise is common in the Academic and Stoic traditions Athenaeus is drawing from; however, he is the earliest extant medical author to distinguish these kinds of training and to treat them as equally important aspects of regimen. In this paper, I propose some reasons why he found this distinction useful, and I examine how he justified incorporating it into his writings on regimen, namely by attributing Plato's beliefs about regimen to Hippocrates, a strategy Galen would adopt well over a century later.