I think his body and mind were both worn out.
My only strength is being of sound mind and body.
Yoga is excellent for the health of your body and mind.
Technically this kanji is heart and somebody, but think about it this way. Where does everything come from inside somebody? The heart! It keeps things going by pumping blood, providing the foundation for both a good mind and body.
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.