Winter gym exercises for building cycling muscles?

[velo]

You will probably find that in addition to spin classes and exercises you will need to spend quite a bit of time on an indoor trainer. Mind numbingly boring and maddening as it is, there is nothing like your own bike and bike seat in a stationary trainer to use to build up TITS (time in the saddle) endurance. In this case,extended time at a comfortable cruising speed, resistance and a lot of good music or videos to keep you occupied are suggested.

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Riding the bike is primary exercise between twice weekly training sessions with a trainer at the gym so don't get to heavy handed with it but do try to build up at least a 2-4 hour TITS time with no speed onus or penalty but simply riding in the saddle in time extended blocks before you really ramp it up outdoors in the spring.

I couldn't agree with this more. You may get the aerobic fitness needed to ride a century, but if you don't spend LOTS of time in your own saddle, your bottom will not be able to endure the time in the saddle. I have seen and heard so very, very many stories of people who are fit enough to ride a century, but they didn't get their butts accustomed to being in their own saddle... and couldn't do the miles. Lots of good advice here, but paramount to success is being comfortable on your bike for 100 miles... and as marni says... the only way to do that is saddle time. Good luck on June 7th!! Have fun!

[jyyanks]

You've already received some great advice but definitely take advantage of spin class. I really got into it this year when a little mom and pop opened in my town and I started going regularly. It's made me a much better cyclist as I really polished up on my endurance and resistance. Granted, I'm not exactly a great cyclist per se, but spin class just prepared me for the past season and I'm still going. Definitely, heed the advice of the experts and get to know your own saddle/bike. Best of Luck!