Saturday, March 03, 2007

A Lesson Learned!

We just worked with Tina Pic in her home in Buford, GA. Tina has just gone through our fitter, Eddie O'Dea, and as a follow up, I was to provide our Myo-facts sEMG/Dartfish for her review.

I arrived on Saturday afternoon, but my bag did not show up until Sunday night, about 9:30pm. Tina was to leave the very next day for a World Cup down-under.

That Sunday morning, I checked a few measurements and set the bike up according to the CAD solution. Later I had the chance to ride with her husband, Chris, in the back of their Jeep. Before long we were hitting speeds of 55-60mph.

The temperature was about 40 Farenheit and I captured most of her riding. Up and down the road we went, uphill and downhill. After we got back to their home, Tina pointed out that she was able to make more watts, up to 40 watts more! I looked at her husband and said, "Are you sure?" I then asked how long she had used her SRM and she said a few years! Tina did say at that point, "I don't know if I could do that for 4 hours." She knew she had worked different muscles.

As I understand it, Tina got to her races and had very little time to adapt to the new fit. The lesson here is the new fit was too much, too soon. We threw the dice and she was not able to adapt to the new fit that soon. Tina pointed out that she was able to make more power, but was not able to go like she needed after about two hours. She had many more hours with her old position.

The explanation for this is in the length-tension and force-velocity properties of the skeletal muscle. Changes in saddle height will alter the range of motion of the legs, and subsequently the length changes experienced by the leg muscles.

Obviously the range of motion that each leg must go through influences the force-production capabilities. Additionally, leg position affects the muscle movements at each joint. Joint torques are generated by the muscles in the leg.

The reality here is a cyclist has the ability to change the working range of the legs. This force can be read by using EMG. As saddle height is increased, the leg muscles turn on earlier in pedaling and stay on longer. They are on longer for a longer period of time and your body needs time to adjust.

Tina did take 4th on the 3rd Stage with the new fit, a super effort. She then decided to move it back to her old saddle height, and won the last Stage. This goes to show you that it's best not to adjust your bike immediately prior a Major race.

Serious cyclits are searching for the competitive edge - one based on fact rather than on tradition or guesswork. They hit the wind tunnels, use powermeters, etc...

So the next time you wish to change your fit, give it some time. We even point this out on our Solution page. It takes time for muscles to get use to a new saddle height, more power or not!

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