Waxing Aerodynamically Didactic

I just made a bike discovery yesterday, I’m really proud of myself for it, and I’d like to share this little tidbit with you. So if you came to the blog today in search of answers to life’s problems, zen, or the pathway of the bodhissitva, you’ve come to the wrong place. If you’re fascinated by wrenching on your own bike, read on.
 
The challenge of time trialing position, and cycling position in general, I suppose, is finding the right balance of aerodynamics and muscular leverage. You must supply the power against and choose the gearing for that leverage yourself. But if you’re trying to find the most powerful aero set up for yourself, here are some ideas:
 
People pay the big bucks for aerodynamic tests in wind tunnels, and while I’m certain there are benefits to be had there that you can’t find on your own, I think you can usually figure out a pretty optimal position for yourself without shelling out much cash. The more aerodynamic position will almost always involve lower handlebars. Handlebar angling is another issue. Some aerobar fitters will tell you that you don’t want to angle your aerobars up because that will force air into your legs and slow you down. On the flip side, look at Levi Leipheimer’s position at the Tour of Cali or Floyd’s position last year–steep angles. Obviously if you’re going to be in that position for a while, you’ll have increased fatigue, but it seems like a steeper upward angle moves the elbow pads a little closer and might even make things a little more comfortable.
 
But there are lots of places you can read about aerodynamics. The bigger question for us is, "How do you become aerodynamic without losing power?"
 
First off, do an aerobic ride for at least an hour and a half in your current position. Then, on another day when you’re fresh and ready for another ride, give your bike the most aero set up you can imagine–Chris Boardman-type aero. Then hop on on the trainer, and try riding in that position for an hour and a half with a heart-rate monitor strapped to your chest. Of course, you have to be familiar with your own HR before you delve into this, but I’m assuming you’ve already done either a max HR test or an LT test (to determine the approximate 90 percent range for your heart rate). Then look at your HR in your new position and compare it with your previous HR. This is going to sound counterintuitive, but if your position is too bent over for you, as in, you’re not flexible enough for it, you’ll struggle to get your HR into the right range–it won’t get high enough, but your perceived rate of exertion will be higher–even on an aerobic ride like the 1.5 hour. You’ll feel fatigued and have the urge to get out of that position and sit up. If you substitute an intensity ride, you’ll find your HR is simply higher than usual, but that you can’t sustain it as long.
 
After that, it’s just a matter of raising your stem until you reach that point where your heart rate responds normally. This is all operating on the assumption that a poor power position will manifest itself in heart rate changes. Of course, if you’re like me, you just get tired of it and put your stem right back where it was.
 
Yeah, my wife thinks I tinker with my bike position too much. She might be right, but at least I’m learning a thing or two along the way.
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