In my previous blog, A Year of Centuries, I had a memorable entry in which I compared a hummingbird's power output to that of a cyclist. The inspiration came from - of all things - a Nancy Drew mystery. I revisited these favorite books from my childhood as I highlighted a wonderful Georgia charity, the Ferst Foundation, which promotes childhood literacy by providing free books to any Georgia child from birth to five years of age. Here's my hummingbird/cyclist analysis:
Also, I found that Nancy Drew can be educational even for adults. One of the characters in The Double Jinx Mystery is a man with an aviary of rare birds. He tells Nancy and her friends George and Bess lots of interesting things about the birds. For example, he says, “When a hummingbird is hovering he has an energy output per unit of weight ten times that of a man who is running nine miles an hour.” This reminded me of the power to weight ratio that we cyclists often use, and so I made a comparison between hummingbirds and cyclists. A nine-minute mile is a very moderate running pace. A 150-pound (68-kg) man running at this pace probably puts out about 125 watts. Therefore, estimate that his power to weight ratio is about 2 watts per kg. That means that a hummingbird’s power to weight ratio is about 20 watts per kg. For comparison, a Tour de France racer has a threshold power to weight ratio of about 5 watts per kg. That’s only ¼ the power to weight ratio of a hovering hummingbird!
Just imagine how fast a hummingbird's metabolism must be! Even when I was training for RAAM a couple of years ago and the critter was always after me (i.e., I was hungry all the time because I was training so much), I wasn't burning nearly the relative number of calories that a hummingbird does.
Randonneuring also involves very long journeys. It's critical to fuel properly for these rides. I try to eat mostly healthy, "real" food on brevets, but I do enjoy the occasional treat. For example, Little Debbie oatmeal cream pies (OCPs) are outstanding bike food. Even on the longest brevets, however, one still should take care not to eat like a hummingbird.