Hi there, I need a new form of cardiovascular exercise. I just got back from a 6 mile run and my knees are killing me, so I think I gotta switch sports. It was either this or swimming and I suck hardcore at swimming. I have pretty much no idea what I'm doing with a bike. I mean I can ride one (who can't?) but I have no idea how to do it correctly. Google told me that a road bike suits runners best, and honestly an occasional competition (like 6 or 8 a year) would be kinda fun, but they didn't tell me why. So I guess my one major question is where do I start? A bike obviously, but do I really need to spend $700 at the bike shop or will last years $250 eBay version work? That and any other tips would help. Thanks!