My thinking is that a problem in the head would present itself in more ways than traveling pain. Perhaps a visit to the doctor is in order, as suggested. Perhaps self analysis can pave the way.
While it is assumed living is a great gift, it can be a pain to some and that pain can settle anywhere. The treatment can vary in any number of ways, self administered or otherwise. You mention leg press. The gym can help us live. So can walking, biking, yoga, meditation, learning, journaling, doing for others, music, hobbies, work, etc.
This is an interesting mystery for us to ponder.