Friday, June 5, 2009

The NEED for SPEED!




I don't know one athlete (triathlete or cyclist) that doesn't want to go FASTER on the bike. Granted there are those that are a little nervous going FAST down steep descents and rather apply the brakes to keep their speed in check. But, for the most part..when you're racing it's all about..the NEED for SPEED...and how to go FASTER!

In order to go faster, especially for Triathlete's (that are out on a course for 5+ hours)..it's not a matter of just exerting raw power on the bike...it's about balancing POWER, COMFORT and AERODYNAMICS. (See Powerpoint Slide above).

This blog, however, is NOT about Power (wow, a break) or Aerodynamics..it's about Comfort. One of the most important aspects of Comfort is "bike fit". That is, properly fitting a bike to your body geometry rather than fitting your body to a specific bike. It always amazes me how athletes just go out and buy a particular bike because their buddys ride one, or their favorite pro triathlete rides one, or they can get a good deal on one at their local bike store (LBS)...not knowing that "geometrically speaking" it could be the worst marriage in the world. So, keep that in mind when purchasing a NEW bike. Demo ride as many as you can (of different make) BEFORE you buy, because some bikes will just fit you better than others..even if they're the same frame size.

If you already have a road bike or Tri bike..and you want to ensure that you're fitted properly..you can either go to your LBS and have them fit you...or do it yourself. A decent "static" fitting will take about an hour and cost approx. $100. A static fitting is one where the LBS will drop a plumb line from the tip of your knee (while your seated on your bike with your foot stationary at the 6 o'clock position) to the center of the pedal axis to check for proper alignment. Then they'll use a goniometer (fancy name for an angle measuring device) to measure knee extension angles. These are the two most important angles that will fit you to your bike properly. A more advanced "dynamic" fitting will take up to four hours and cost approx. $400. A dynamic fitting is one where the LBS will use either a hi-speed camera or video to check for proper alignment, knee extension angles and other important angles. With dynamic fits, the LBS is most often fitting the bike to you. A "dynamic" fit is more accurate/precise than a "static" fit, just like a "dynamic" spin balance of your cars tires is better than a "static" balance. A proper warmup on the trainer is normally required before a dynamic fit is performed.

If you're on a shoestring budget..you can easily do a "quick fit" check at home. All you need is a digital camera, computer, protractor, ruler, black sharpie marker, and some clear transparency film to cover your computer monitor..while you draw lines/angles on it. You just have someone take a photo of you on your bike (on a trainer), in whatever position you want to ride (Aero-bars, on the hoods or drops), and then upload the file into your computer and onto your computer screen. Then, you tape the film transparency over your computer screen image and start tracing the lines with your sharpie. When you're done, you use your ruler and protractor to measure alignment and critical angles. Or, if you have a good Photo Editing Software program, like Adobe Photoshop, you can forget the sharpie and transparency film and just overlay lines through your ankles, legs, hips and shoulders (See photo above). BTW, the photo above (of me) is with a Cannondale road bike with a seat-tube angle of 73.5 degrees. A Tri-bike, with a seat tube angle closer to 80 degrees, would move me more forward, allowing me to raise my seat, thus dropping my arms more and creating a flatter back...and ultimately a more "Aero" position. I was actually able to get my position flatter since this photo was taken. Since I couldn't get a more forward position, based on the 73.5 deg seat tube angle, and the fact that my seat was as far forward as it could go, I bought an off-set seat post that allowed my seat to go MORE forward. Thus, seat height up, creating a more acute angle of the arms where you currently see 110 deg. angle in the photo..and a flatter back.

I'm not going to go into the actual bike fitting procedure for you here, because I don't have the time, but what I am going to do is provide you with a great article on bike fit from Dan Empfield..that will pretty much explain everything you need to know about proper bike fit...so you can either do it yourself at home..or be able to speak intelligently when you take your bike to your LBS to get fit. (Don't sound too smart at the LBS on bike fit, after you read the article by Dan, or you'll fluster your LBS fitter...haha) Here's the link:


Good luck, and if you have any questions..email me: mullerrj@comcast.net Be Aero, Power Up, In-Comfort= Go Fast!

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