To keep the body in good health is a duty... otherwise we shall not be able to keep our mind strong and clear. - Buddha
Thus to keep oneself healthy is a sacred duty, to ward off delusion and error on the mental plane as well. This is important in terms of cultivating viveka and discrimination between the real and unreal.
Nicholas, have you read Yogananda's book 'Autobiography of a Yogi' !
I read it as a teenager, and it helped me to get rid of the fear of death and loss, and brought me closer to the spiritual path. The Bhagavad Gita also had a similar influence on me.
Yes indeed, many years ago of course ( my age is over 70). It is a spiritual classic!