Larry - Even in the central south, the winter months make it hard to get out and ride. We ride outside as much as the weather will permit, but supplement saddle time with 'spin classes' at the local YMCA a couple or three times a week.
As you know, spin classes are actually cardio exercises performed on a stationary bicycle led by an instructor to the beat of hard driving music. Done right, it's a real work out. Other than the obvious, there really is not much similarity between riding a stationary bike and being on the road. Still, we can definitely tell that our overall fitness is enhanced by the classes and that certainly crosses over to improved performance on the road. Spinning prepares you for the cardio jumps that go with most club rides. Club rides, at one point or another, always turn into little 'rat races' of who can top the hill first or beat the rest of us to the city limits sign, etc. Whereas tour style riding is more a slow and steady pace that you can sustain for hours/days on end.
One of the surprises that we discovered early on with touring was upon our return after riding hundreds of miles over several consecutive days of riding, that we were out of shape for the club rides! Our hearts were way strong for long and steady, but had temporarily 'forgotten' how to do those sudden jumps that go with club rides. What a bummer for a few rides until we get readjusted.
Back to spin classes. One of the things I miss in the winter time is working up a good sweat. Yuck, but it's true. I can just feel those toxins oozing out of my body when the sweat starts to flow. I guess I'm also looking for those little endomorphs that go with vigorous exercise (runner's high) that make us feel so good. Spin classes definitely get you hot - and for us - they're getting us ready for THE BIG RIDE.
Martha's a spin warrior. Sometimes I'm a little bit of a wuss.