Saturday, August 1, 2009

position check

An eye infection has me sleeping poorly and feeling generally crappy. In these situations, I prefer to take a few days off from worrying about training (except for stretching), get plenty of rest, and focus on getting better.

A good chance for a sanity check on my position.

CyclingNews did a nice article about the Saxo Bank Squad team getting fitted by Andy Pruitt. Specialized, who sponsors the team, likes to represent itself as experts in ergonomics, and so really play up their relationship with Andy Pruitt, a respected bike fitter who wrote a nice book on the subject (not as "complete" as the title would imply, but definitely worth the read).

In the cyclingnews story, there was this side shot of Frank Schleck, showing a side view. I'll take this as an example of, for Frank, a relatively exemplary position.


Frank Schleck fitted by Andy Pruitt (CyclingNews).


So, how do I compare?

Leaning the bike against the wall (not the best: a trainer would be better) I took photos of myself in various positions, extracting angles with Gimp.





Well, a few observations:
  1. My leg angle of 33.5 degrees is within the range recommended by Pruitt, which is 25 to 35 degrees, but near the upper end. I tend to ride with my toe down, though: 26.8 degrees in the photo.
  2. My knee is slightly more forward than Pruitt suggests. But rotating the body forward shouldn't make much difference as long as all the angles are good. I like being in a slightly more forward position. Compensating for an extra cm on the stem length? No big deal in any case. Christopher at PK Cycling established my present set-back, and I trust him.
  3. Frank appears to be a lot lower than I am (he's on the tops and he's already fairly low). Well, he's a pro and I'm not... I clearly am more aero in the drops than on the hoods. Were I to lower my bars I wouldn't be comfortable in the drops, and would spend more time on the tops and less on the hoods. This position seems about as aggressive as I can go and still be comfortable.
  4. li>My head position looks okay. I've been focusing a lot on relaxing my shoulders, even shrugging a bit (not doing that here), and letting my head drop as I look up to see the road. I had a tendency to ride with my face perpendicular to my direction of motion, which increases wind resistance.

Conclusion: nothing seems terribly broken here.

2 comments:

Ron said...

Dan,

Pretty cool. See, you can also use a long Goniometer. Another option is a video analysis software free for download called Kinovea. Visit kinovea.org. Latest version is out. Hope eyes feel better over time.

djconnel said...

Wow -- that is really cool software. Thanks for the link!