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"The anatomy of bike position" article discussion
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http://www.cyclingnews.com/...s/2008/bike_position

I found some interesting points in the above bike fit article, specifically the approach to bike fitting from a neurological basis.

A few excerpts:

"90% of brain activity is tied up in relating the body to gravity" (quote: Roger Sperry - 1981 Nobel Prize Winner for brain research)."

"Our external musculature works in one of two ways, posturally or phasically. If beset by a challenge, the brain will ALWAYS prioritise the muscles acting posturally as they are the ones that allow us to resist gravity, maintain an erect position and play a major part in breathing. In contrast muscles acting phasically are the muscles that generate power to propel bicycle and rider. Yet the brain gives them a lower priority because there is greater evolutionary value in being able to breathe than there is in being able to move.
The postural / phasic split is a generalisation but an accurate one. Some postural muscles like the hamstrings and gastrocnemius act phasically on a bike because they are relieved of the need to help maintain an erect posture such as they are when standing."

"...there is a neurological basis to an optimal bike position. To be most efficient, we need to sit on a bike in such a way as to enlist the minimum amount of postural musculature. If we achieve that, we can devote the greatest effort, both neurologically and physiologically, to switching on and off the muscles acting phasically that generate power, and the minimum effort to controlling the higher priority postural muscles that allow us to hold a position on a bike relative to gravity. When needlessly enlisted, these postural muscles rob heart beats, blood flow and oxygen from the muscles that propel the bike and by doing so, diminish performance."
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Re: "The anatomy of bike position" article discussion [WiScott] [ In reply to ]
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Read the article earlier this morning. I have nothing to contribute to this thread other than to state I am eagerly awaiting responses and replies.

David K
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Re: "The anatomy of bike position" article discussion [WiScott] [ In reply to ]
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Does that mean I'd be quicker if I added some carbon training wheels?
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Re: "The anatomy of bike position" article discussion [WiScott] [ In reply to ]
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There seems to be a fair amount of common sense to the above notions. Of course, someone will now ask for all the research that backs this up!
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Re: "The anatomy of bike position" article discussion [WiScott] [ In reply to ]
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Perhaps an oversimplified paraphrase would be: "Don't recruit unnecessary muscles, it will increase your cycling efficiency".

He said something that, if I understand correctly, seems wrong.
He indicates that it's better to involve core muscles for your stability on the bike rather than shoulder complex muscles. I think the core muscles are bigger and would use more oxygen as well as restrict breathing more (we breath from the bottom, not the top ala diaphragm).
I find it good to have most of my body weight on my elbows so that I can relax my core rather than trying to hold myself light on the handle bars by recruiting my core.
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Re: "The anatomy of bike position" article discussion [devashish_paul] [ In reply to ]
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Dev, you read my mind!

Seriously, it sounds like a mixture of common sense and unsupported handwaving. Which parts are which, and whether any of it is actionable ... well, who knows?
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Re: "The anatomy of bike position" article discussion [MuffinTop] [ In reply to ]
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I think a number of items that he claims as fact are oversimplified and could be disputed. If he said that common sense and logic would suggest....xyz...then I think the reader can then do some educated analysis and synthesis of the brain body connection and how it applies to the bike fit. Being a big fan of eastern philosophies I'm very supportive of any approach that places the brain and neural efficiency as an integral part of the "performance paradox".

The other day to analyze the role of blood sugar decline to the brain, I tried the simple task of calculating the tangent of each 30 degree increment around the circle during a 3 minute hill repeat...this is something that is pretty simple to do when doing nothing else (tantheta = opposite over adjacent......), but when blood sugar drops during exercise its almost impossible to do this type of math. The amount of processing that the brain does to sustain high intensity physical exertion is really underestimated.

If I can't do simple math like calculating mile splits early in an event, then this is a good indicator that I am likely using up way too much blood sugar too early....
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