That's right, and once you're into a routine and have developed or regained quite a bit of fitness, don't worry if you take a few days or even WEEKS off now and then. It's surprising how little you lose and how quickly you get back to the level you were at. Sometimes there's a tendency to think "I gotta keep this up or I'll be right back where I was." But the reality isn't that pessimistic. I quit riding for a variety of reasons sometime in 1997, and had to have a third of my stomach removed in August 1999 due to a benign (thank goodness) tumor. I decided to ride again, and started up in April 2000. No luck! I couldn't go more than a mile without almost passing out. Once I had to lie on the ground for several minutes because I couldn't even stand.

But it turned out it wasn't because I was out of shape, it was because the surgery took longer to heal than I reckoned. It takes sometimes a whole year--with me, it took a little over a year.

After that, I got back on my bike again and within a couple of weeks (not months!) I was at the level I enjoyed when I was commuting every day. So what you hear about losing fitness is sometimes a bit exaggerated, and the cause of unnecessary worry.