Originally Posted by
carpediemracing
I would definitely get your first "serious" bike fit at a shop that knows what it's doing.
I got my first bike from a LBS, but got a poor fit. I think they sold me the size they had in stock rather than the size I really needed. I rode it for a year before ordering online the size I knew I needed, based on competitivefit.com. I could tell I was cramped on my bike, and knew about how much larger size I needed. I went from a 50 cm bike with 535 mm top tube to a 55 cm bike with 555 cm top tube. The bike is SO much more comfortable now. I wish the LBS had done a better job fitting me in the first place. Make sure they really take the time to measure and fit you. Don't be tempted with "this looks about right, try it and see" like I did.