Tuesday, October 02, 2007

Bones vs. Muscles!

Basic Biomechanics: The Spinal Elements

You'll hear everything about the functionality of the body and how software measuring is not used in determining an optimal bike setup. Many dismiss the facts, considering them hype for money and voodoo, simply because they do not have the software. Perhaps one should ask a fitter about his/her education, including the subjects studied, a number mechanical classes taken, degrees held, and how current these qualifying factors are. Perhaps the questions should be about their models, and how they came to terms with the mechanical demands placed on the bone structure during cycling.

Think about it: the industry wants to move bikes, specifically their brands, and they are not interested in changing parts for you, only selling them to you, such as stems and seatposts for example. The industry doesn't make money by fitting you. This fact allows for other companies to move in. The bike store only wants to sell the bike that they've already payed for! You can't blame them, it's simple retail.

Most of us know that muscles will adapt to a certain range of motion and a line of pull. The pulling direction is the key; if miss on this, your game is over.

The next time you visit your local pro shop, or pro bike fitter, ask yourself these important questions: How did they arrive at the fit they are using now? Is this just another basic fit or am I getting the real deal? You don't have to waste your game on guess work, because we have the software and the results. After all, it's your money.

A few facts about bones.

The bony vertebral bodies are the primary load-bearing structures of the spine. Bone is a two-phase composite material comprising of `mineral salts (making the bone harder than muscle) and a matrix of collagen and ground substance (giving the bone flexibility and resilience). Bone is an anisotropic material, exhibiting different mechanical properties when loaded in different directions. It is strongest and stiffest in compression, so you had better get your cockpit right.

Bone fractures usually occur due to complex loading conditions, involving combinations of tension/compression, bending, shear or torsion. Like ligaments, bone exhibits some viscoelastic behavior and is stiffer, can sustain higher loads before failing, and stores more energy (correct fit) when loaded at higher rates.

Bone remodels in response to the mechanical demands placed on it, which are affected by the external loads, as well as the muscle loading. The next time you ride, allow for the compression of the mechanical demands on your spine to adapt, and it will make a difference. Any stem or handlebar setup that extends you too far can hurt you, and also decrease the energy transfer to the drive-train. Cortical bone is the outer dense bone of the vertebral body. Within the cortical bone is a complex structure of cancellous bone, referred to as trabecular bone.

Next time you go into a building, look at its structure, for it is what holds the building up.

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