Based on his heart rate monitor, he thinks that burned about 100,000 calories, which if stored as body fat would be about 30 pounds. A pound of fat is roughly equivalent to a pound of gasoline in terms of energy stored. A gallon of gasoline weighs about 6 pounds, so call it 5 gallons of gasoline. Which implies about 340 mpg.
Pretty cool. People say that bicycling costs no gas, but of course you do have to eat to fuel yourself. We're not counting tires, because we don't count tires on cars either.
If you've seen the recent media coverage on how much exercise you need to do per week to maintain weight loss, you know it confirms what has shown up time and time again: a little over 2000 calories worth of exercise a week (about an hour a day most days of moderate exercise, 3 miles of walking per day, etc -- it all works out roughly equivalent). This implies that R. got enough over the course of the year bicycling to work out about right per week for the whole year -- just from bicycling, which he can only really do 8 months a year or less. Also, in 2007, he had a pretty bad fall and broke his collar bone which took about three weeks to recover from enough to ride again.
No wonder he's in good shape.