When I had my thyroid removed, I asked if I would be able to play the violin afterwards. When the doctor said yes, I said that was great 'cause I never could play the violin before.
Actually I have no idea but I hope a little humor helps you feel better - sounds like you'll be able to weather this without a problem, best of luck.
LOL! Actually I've never run a marathon before, but I've been training for the Cherry Blossom 10-miler (looks like I won't make it this year). After the last 5-miler I thought, well, I could do that twice. So if I can run 10 miles, I can run a half marathon. And if I can run a half, I can run a whole one. It's just math!