Age isn't as bad as disability. Everyone ages—that is, if they're lucky enough to keep their health and can avoid accidents.
Is it better to have loved and lost than never to have loved? Substituting walk for love, does the same apply? I still glide without an impediment in my imagination.
Does Stephen Hawking think back to his youth—walking young and free with his friends at university? These same thoughts must drift in and out of everyone's mind.
I hark back to the Desiderata. 'Gracefully surrendering the things of youth'. Enjoy this depiction.
Desiderata video: http://youtu.be/2yNJaKF9sXA