Answer from The Exercist: Low repetitions and heavy weights are the only way to get big. Most cyclists include training with heavy weights to stay strong. Cycling is all high repetitions. A beginner will gain muscle with any strength program as their muscles are adapting to change. Keep the cycling resistance medium to light max and you will be able to enjoy the exercise. Have fun!!

Answer from Ken Moody: Erika, I always tell my clients to look at professional athletes bodies to help them decide what sport they might like to try. And if you look at a physique like, say, Lance Armstrong's, you'll notice that his thighs are not out of proportion to his body. Now, take a look at an athlete like Dan Jansen or Bonnie Blair (Speed skaters) and you'll notice really BIG THIGHS!!! The class I teach primarily here in New York is Spinning and I have to tell you, I have heard so many of the myths surrounding cycling. I have even heard of something called "Spin Butt". And the fact is, being a man, I have always tried to maintain my rather large thighs and butt. (Personal preference, I suppose.) But since I started teaching Spinning my butt and thighs have gotten smaller. (Oh well!) I guess I'm gonna hafta try power lifting to get mine back. But you will have no thigh problems with cycling. I would just try to avoid a lot of hill training. That would, as my colleague said, increase the resistance and lower the reps. (Maybe that's what I'll do to get my thunder thighs back!)