The character is in his mid-thirties, and otherwise in good shape. He has exercised as much as his condition would allow prior to his repair, and has a strong drive to do whatever it takes to restore his mobility. This story is not set in this world, and so modern medical procedures and equipment are not available to him. There are however, other technologies that could assist, if needed, but I'm hoping that exercise (resistance training and stretching exercises, for instance) would be sufficient.
I have googled recovery/rehabilitation for muscular atrophy, and rehabilitation for leg injuries, but have not had luck finding the information I need. If anyone could help out, I'd appreciate it very much! Thanks!