"And because the body is in a bad condition, loss of memory, depression, discontent, insanity often assail the mind so violently as to drive whatever knowledge it contains clean out of it. But a sound and healthy body is a strong protection to a man, and at least there is no danger then of such a calamity happening to him through physical weakness: on the contrary, it is likely that his sound condition will serve to produce effects the opposite of those that arise from bad condition. And surely a man of sense would submit to anything to obtain the effects that are the opposite of those mentioned in my list. was also what seneca said
i also wanted to add this other part and mention, it was at a time where being fit was almost certain a guarantee for 99% of the male population as well because a lot of men became soldiers at this time