Ah, you'd probably be even sicker if you hadn't gone out and gotten some sun.

100 miles on a mountainbike is somewhat ambitious (even 62 if you're thinking metric century) - but on the other hand, when I was unemployed, I made TONS of progress in riding 'cause I could go out for half an hour in the morning and then go out in the evening for an hour or so. I did my first century that October... more than ten weeks and I had already had 2 years of casual riding under my belt... so go for the goal, but even if you don't get there, you're way ahead of what last year's slothful body could handle! I know that at some point, at dawn, it wasn't my *bike* saying "please, a ride?" it was that strange new body saying "yea! it's dawn! let's ride!" and though I have always had a lot of energy, gettin gout of bed before noon went AGAINST my very nature... my poor brain didn't know what to do except go along with it!