August 31, 2012

Strava Just Called Me Fat

I recently started uploading ride data to Strava, the online competitive social site for cyclists and runners. You go out and record a ride with your GPS enabled device and then upload it to the site. Then, in a split second, you can see how you stack up against other cyclists who have ridden the same segments of road.

I've always known in the back of my head that the extra pounds I'm carrying have impacted my cycling and that I have to work a little bit harder in order to keep up with a skinnier cyclist of comparable fitness. It's simple physics. Friction and gravity resist you as you go up a hill, so having more mass means gravity pulls you more, meaning you need more power to go up the hill. Being bigger also causes more surface area, which creates friction as air drags around you.

I knew this. I understood it cognitively, but I had never seen it quantified before. How big of a difference could a few pounds make, really? What I kept noticing in the leader boards over and over again was people with less power output besting my time. Again and again I would see things like this example below (my time shaded pink).

At first I was thinking, how is it possible that I put out more power but yet have the slower time? Then I realized that the pics of these people who bested me were all of people 50 to 100 pounds lighter than me. They were going faster because they didn't have as much gravity and friction counteracting their power. So, they required less power to go faster.

It's unrealistic for me to aspire to the ideal cyclists form because I just don't have the frame for it. However, I can still do a lot to improve my performance by shedding the extra pounds. And now I've got just a little bit more motivation to do so. Ironically, that motivation comes in the form of laziness. I don't want to work that hard (over 50 watts harder in the example above) for my slower results. I want it to come easier. 

1 comment:

  1. Probably the suggestion to just ride down hill more where the extra gravity will help isn't what you're looking for? I hear you though--I don't ride, but I've been a runner and keep trying to get going again, but the extra pounds are making it so much harder!