Monday, December 13, 2010

Triathletes: How those perverted top-tube humpers can teach us a thing or two

Dear BRH:

I do all my training on the hoods, but when I get in races, I'm often in breakaways and doing leadouts where I'm in my drops. Is there any benefit to training in the drops?

Maude Lebowski

Thanks for your question, Maude.

My first thought is that this is a really douchy, petty kind of concern, especially in relation to truly important question such as "Is there a God?" and "Which is better: Philly cheese steaks or Italian beefs?"

But we spend way too much money on aero "weaponry" and time in basements on trainers watching "Hong Kong kung fu movies" (as the Dutchman recently confessed to me) to ignore body position on a bike. So I guess, relative to the severity of our other doucheyness, it's actually a reasonable question.

The way to improve your aerodynamics on a road bike, it turns out, is fairly simple: train in an aerodynamic position.

This is what a 2004 study concluded. The study compared the power outpute of triathletes who train in the aero position (AT, shown in blue below) and regular road cyclists (CT, shown in red below). The study tested peak power and mean power in two positions for both groups.

Check out the red CT group--the guys who ride (and walk) upright, like you and I. Peak power is around 750watts in the upright position, but falls off to less than 700 watts in the aero position. Mean power shows the same effect: lots of power in the upright position and a big drop going to the drops.

Now look at the aero-trainers (AT), the guys who train in the aero position. You'd think that everyone, even triathletes, put out more power in the upright position, but this turns out not to be true. For those who train in the aero position, they can actually put out more power in the aero tuck than they can in the upright position.

You'll also notice, however, that roadies crush triathletes when in the upright position.

The authors conclude: "it is recommended that athletes train in the position in which they race."

This is, I think, a vast oversimplification. It completely ignores other physiological factors at play--for example, maybe triathletes are simply perverted freaks of nature who should not be encouraged to train their perverse way. There are a lot of problems with how this study is organized (among them, the problem of comparing two groups as different as they two are).

On the other hand, I think the study does affirm what Joel Friel calls the principle of specificity--"Basically, the specificity principle says that if you want to become good at something you need to do that thing."

If you're a breakaway specialist, Maude, practice riding in the drops. That's my advice.


Tim Rugg said...

I hate it when you try to protect my identity.

Nick said...

you are what you eat?

practice what you preach?

train how you race?

the answer is italian beef. which there is none of in DC.

Calvini said...

Nick, I'm happy to point you to Chidogo's on 14th and U, where there are decent Italian beefs. Your choice of pepper, and they'll even let you watch them dunk it in the "meat juice."

Rugg, you're like fish left under the car seat on a hot summer day. All the pine fresheners in the world can't hide the scent of Rugg.

Nick said...

oh, that place opened recently, didn't it? i may have to look into it.

Anonymous said...

I am unconvinced by the aero-power study. If they tested on triathletes, they are likely to be on Tri/TT bikes, meaning a steeper seat tube and lower headtube. If I sit upright on my TT bike, I simply can't generate much power since the bike was designed around being in the aero position. So, rather than the lesson being specificity, it could be that using equipment the way its meant to be used yields greatest results.

Calvini said...

Anon, your point would be right if the subjects performed the test on their own bikes (triathletes on TT bikes, roadies on road bikes), but they don't.

Here's the exact description from the paper:
"Both cyclists and triathletes were asked to bring in their cycling shoes and pedals to be outfitted on the ergometer in order to better simulate racing conditions. A 30 s Wingate test was used to determine power output on a cycle ergometer (Monark 824 E, Sweden). There is a strong relationship between ergometer performance and racing performance (8). During the aero trial, the ergometer was fitted with Syntace aero bars (Scott, US). Resistance was set at 0.075 kp/kg body mass (12). The subjects were required to pedal at an all out effort for 30 s. The Sports Medicine Industries (SMI) computerized program (Sports Medicine Industries, St. Cloud, MN) with an infrared sensor was used to record peak power (PP), mean power (MP), and % decrease in power (%D). Subjects were given a rolling start to break initial inertia and then given a 10 s countdown before resistance was applied. Saddle height was set at a knee angle of 25-35° (13) using a goniometer (LeMond Fitness Inc.). Participants were required to conduct two Wingate tests with at least one day of rest between for recovery. One trial was completed in an aero position, and the other was performed in an upright position."

All subjects performed the test on the same bike, and in the same position. Therefore, the differences had to be THEM (and, presumably, how they trained) not the bikes.

Anonymous said...

that does alleviate some external variable, but I would assume the ergometer was set up to replicate their own riding position. Obviously they did not make them all ride with the same seat height, stem height or arm reach. Using the ergometer only eliminates questions of consistent power measurement.

Not trying to be a naysayer, just pointing out an area of improvement for the research method. Interesting stuff, just not completely convinced.

Calvini said...

Yep, I think you're right, Anon. I think there's a lot of little things wrong with how the study is set up, but nothing that outright disqualifies the results.

Foremost, I can't imagine generating more power wrapped around aero bars than I do standing up. But maybe that's because I'm not a perverted triathlete. I almost think that result alone points to what my stats professor would call an "f'd up" study.

Peter Warner said...

Study aside, I'm in agreement with your conclusion.

Now bring back Analogy Friday! (or whatever day it was)