I think what I might do is try spinning. It can't be as fun as exploring the world out there on two feet, but at least it can provide the exercise needed. Today I'm resting on doctors orders, though. So far, no there's no life after numb toes, sadly.
What would you do if you had to stop running? Interesting horror story to tell yourself. But it turns out there are a few OK things out there to take its place. For instance today I went to the local swimming pool, and just sort of wallowed around there (either because I'm resting, or because I'm lazy; I'm not so sure which). When the water is only 18 degrees Celsius, it's actually quite handy being a bit fat. Blubber really does insulate nicely. (And I think that's scientifically proven - your cross Channel swimmers try to put on a bit of padding before that race, even today, AFAIK).
Should I post some loud and inappropriate spinning music then? I think I shouldn't, but I probably will ... YES! ...
I reckon one could get legs like Arnold Schwarzenegger spinning to that.