Vek, I agree 100%. If you only rode, and didn't cross-train, you'd create muscle imbalances in your legs that would be a net negative.
It's one hell of a FUN way for middle age guys to get into very good aerobic shape at low impact levels to the joints, though. Did I mention how fun it is? 45 minutes on a stationary trainer? Bleah. 45 minutes climbing a ridge breathing the air of creation and getting bugs in my teeth on the ensuing descent? Sign me UP!!
