Despite my insistence that bike commuting is not a sport and does not require a special wardrobe, the first few votes in my reader poll suggest that a major reason people don’t bike commute is that they don’t want to get their work clothes sweaty. Apparently people are less worried about the dangers of biking in NY than they are about showing up to work with a bit of sweat on their brow. By now I’ve heard this excuse several times from good friends so I feel compelled to dispel this myth once and for all.
A short, “no-brainer” bike commute will not make you sweat. In fact, you might even use less energy biking to work than you already use walking to the subway. Often when I tell people that I bike for transportation they say, “What good exercise.” I’ve always kind of shrugged this comment off because my primary reason for biking is convenience, not physical fitness. But the more I think about it, I think that statement is just plain wrong and misleading. It’s often cited that cities with a strong biking culture are less obese and that cycling is a great way to improve public health. The health benefit is usually stressed in bike advocacy campaigns, but I think that promoting “biking as exercise” discourages more cyclists than it attracts.
The fact is, you don’t have to be in terrific shape to bike short distances, and biking to work might not help you lose weight. Granted, increased cycling can probably make a difference in cities where most people drive from their homes directly to their destination, but New York is not that sort of city. Most people here walk and take public transportation, and boy do we walk a lot. I can’t tell you how many exhausted tourists I’ve heard say, “Man, we walked everywhere today.” To which I’ll I usually say, “Welcome to New York, it’s a walking city.”
A couple of weeks ago my old bike was getting fixed and my new bike hadn’t yet arrived, so unfortunately I found myself walking, taking the subway, or hailing a cab. Not only did that hurt my wallet, it really hurt my legs. I’m not used to walking and I found myself chafed and tired by the end of the week. Oddly enough when talking with my co-worker Wallace he made the same observation. Walking is hard and the last time he had to do it, he too got tired. You see, Wallace and I both bike from door to door most places we go, and walk very little. Which made me wonder, “Does it require less energy to bike than to walk?” And the answer, somewhat surprisingly, is yes, much less.
A bicycle is perhaps the world’s most energy efficient device and it takes roughly 1/3 the energy to bike than it does to walk the same distance. According to this chart from the Worldwatch institute, biking uses just 35 calories per passenger mile, compared to 100 calories by foot (and 1,860 by car).
The book Comparative Biomechanics says, “legged locomotion…wins no prizes for efficiency. At 4.5 miles per hour, going a given distance by cycling takes 2.2 times less energy than walking. At 9 miles an hour, cycling takes 3.7 times less energy than running. Put another way, investing 15 watts of metabolic input per kilogram of body weight can move you at 19 miles per hour if cycling, but only 9 miles per hour if running.” The problem is our limbs “reciprocate rather than rotate” and the back and forth motion requires repeatedly starting and stopping the legs. That’s why when you “add a bicycle to a person you reduce threefold the work needed to go a given distance.”
The chart below shows the calories burnt per pound per minute for different exercises. A person biking 15 mph burns roughly the same calories as someone walking at 4.5 mph. This means that expending the same energy over the same time you can bike over three times further cycling than walking.
When I used to take transit to work, I walked .2 miles from Bleecker St to W4th, and then .7 miles from Penn Station to 37th and 11th Avenue. Walking .9 miles at 4.5 mph takes 12 minutes and burns 109.4 calories. Biking the 2.3 miles from Bleecker St. to work at 15 mph would take 9 minutes of actual cycling, and burn 85.6 calories. For this commute, I actually burned fewer calories by biking the full distance.
Now I realize I had a very short commute to begin with, but there are many people that walk about a mile each way using transit but live within 3 miles from their place of work. A person living in Chelsea and working on the Upper East Side, for example, would probably burn less energy biking to work. Someone living in Williamsburg or Greenpoint and working in Downtown Brooklyn or Lower Manhattan, can choose a one transfer commute that would require a lot of walking, or a quick 3 mile bicycle ride. I’m not trying to say that biking isn’t good for you, it’s just that you’re not going to be burning a lot of calories biking on flat ground for less than 5 miles. In fact, in some cases you’ll probably burn less (and sweat less) than if you walk and take transit.
Finally, not only are you expending less energy, but you are traveling in a much more pleasant way. When biking at slow speeds you generate a nice breeze without raising your heart rate or breaking a sweat. Compare that to waiting underground for the subway in August, then cramming into a packed car filled with similarly sweaty and stinky straphangers. And you say you’ll sweat more on a bike? Uh, I think not.
Filed under: Why bike?