The decision is really simple for me: we are a single-car family (by choice), so I bike and my wife drives the car.

But beyond that, I would bike even if we had two cars. However, the thought of owning more than one car sends me into fits of financial distress, at the thought of buying, owning, fueling, maintaining, and insuring a second car. It would be a huge financial burden for us to have more than one car.

But the simple truth is that I really don't like cars and driving. They aggravate me. I feel extremely limited and, paradoxically, slow, when I'm driving a car. I have greater freedom of movement on a bike. If I don't ride to/from work, I feel disjointed, stressed, and out-of-sorts.

And I really love cycling. I jumped on a bike for the first time when I was 5 years old (sans training wheels), and I haven't been without a bike since then. Except for this one time when I had my (one and only) bicycle stolen, and it took me a couple of weeks to replace it. I joke with my wife that I'll probably die on my bike. I honestly don't know if I would want to continue living if I lost the use of my legs.

As far as body/weight/fitness goes, I'm probably better off than most guys my age. I spent 12 years working in the natural foods retail business when I was 18-30 years old, and I've carried that diet/lifestyle with me throughout my life. I don't eat much carb-y food: my diet consists of primarily meats, veggies, fruits, nuts, seeds. I follow Michael Pollan's advise: "Eat real food, mostly plants, not too much." Mostly paleo-ish, but as you have seen, I do enjoy a beer every now and again. Wheat and dairy don't agree with me, so I avoid those. We don't eat a lot of pre-packaged foods, and I am very fortunate to be married to an excellent cook. I think Mark's Daily Apple has lots of good info for dietary guidelines, and how to "look good naked."