In this post on draft-legal triathlons, I discussed the advantages of riding close to someone else’s rear wheel and how such considerations influence strategy in draft-legal races. Those aerodynamic benefits are also the source of much anger in races that don’t allow drafting.
Cheating is an often-discussed problem in long-course racing and the popular consensus is that illegal drafting is epidemic even at the top levels of the most sacred racecourses in the world. This post will probably do little to assuage the hurt feelings, because it reveals an underappreciated benefit of cheating:
Not only are cheaters getting an unfair advantage, law-abiding triathletes actually get penalized for obeying the rules. You get punished for doing the right thing not once, but twice.
Let’s start by setting up the problem.
Here is USA Triathlon’s “draft box,” which is used as the standard in all USAT-sanctioned races that don’t allow drafting. The rules state that the closest legal distance between two athletes is a 7-meter space between the front wheel of the lead rider to the front wheel of the trailing rider. This is problematic enough in the first place, as any sensible cyclist would gauge their distance off the rear wheel of the person they’re following. Because that’s the wheel they can see! But it doesn’t make sense when you look at it from a scientific standpoint, either.
We’ve already analyzed the merit of this box in our last post, coming at it from the viewpoint of a draft-legal situation. The 7-meter rule certainly keeps the pursuing athlete from cheating. But our analysis in this post showed that you don’t actually start drafting until you get much closer than that. There’s no aerodynamic benefit until the distance between athletes is less than 3 meters (this is distance between rear wheel of the leading rider and front wheel of the following rider, see diagram). Estimating the length of a bicycle to be 1.5 meters, it doesn’t take a geometry whiz to realize that USA Triathlon’s draft box is keeping triathletes much farther back than is really necessary. You could debate exact measurements, but approximately 2.5 meters could be chopped off the draft box without giving anyone an unfair advantage. That’s just a little over 8 feet.
How big a difference can that really make for people who obey the rules?
As it turns out, a very big one when you consider the other half of the problem. Join us next week as we explore: Evil Twins, Triathlon’s Draft Box, and Race Day Interval Workouts.
Does the science of speed interest you? You’ll be fascinated by Jim Gourley’s new book FASTER: Demystifying the Science of Triathlon Speed.
Jim Gourley is an astronautical engineer and triathlon journalist. His new book FASTER takes a scientific look at triathlon to see what truly makes you faster—and busts the myths and doublespeak that waste your money and race times. With science on your side, you’ll make the smart calls that will make you a better, faster triathlete.