I took up biking after having knee surgery and gave up running. I'm wanting to enter a triathlon but really don't want to spend a ton of time doing the running part of the training due to the impact it has on my knees. My question to you fellow clydes I guess is have you seen enough overall improvement in fitness by cycling for it to help improve your fitness for running. I previously ran 3 days a week and I'm not willing to do that to my body again to get ready for a triathlon. I guess I could always walk the running portion.