This is a fun article about Oregon, riding bikes, and being more fit:

CNN.com – Experts: Bikes help Oregon check obesity – Aug 24, 2005: “It’s not a marathon, nor is it a grueling hike. Yet diet experts say it’s the kind of daily activity that could hold the secret to why Oregon is the only state in the nation where the obesity rate did not increase in the past year.”

I’m sure there are other variables, but it’s a start.