Thursday, August 21, 2008

Freaks of nature, or master of their bodies?



The stars of these Olympics are Bolt and Phelps for sure. Their dominance in their respective disciplines have raised questions, and the most selling answer I came across is the "freak of nature" explanation, which tries to explain their dominance by stressing the suitability of different features of their bodies to their disciplines. Phelps is "like a boat" and so "flexible" that he cannot jog, Usain has the "legs of a kangaroo." I not only do not disagree with these explanations, but also think that these explanations which are easier to sell for the media is against the Olympic spirit. Let me try to explain why.

I do not deny that some certain features bring competitive advantages in certain sports. However, this only explains why they are better than the average runner or swimmer, but not why they are so good among the best of the best, against whom they are competing. Those guys have the same advantageous features. So whats the source of their extraordinary performance?

Being an engineer, I will bring a scientific explanation.

Take running for example. Earlier in this blog, I had written about the mechanical explanation of human walking. Basically, upper body behaves like a weight attached to the inverse pendulum of the legs. That was just half of the explanation, as it explains one step only. In order to set up another hinge point and a connected pendulum on the next step, the lover leg also behaves like a pendulum around the knee joint. The lover portion of the leg that is not touching the ground is contracted as the higher part is extended during the step. Therefore walking, and running are actually the result of a mechanical system of 4 bars and 4 joints, which implement 2 dynamic inverse pendulums working in synchronization with each other -note I have ignored the ankle joints the feet, and the hundreds of muscles involved in keeping in balance for simpflifiation. One can model this mathematically, and can find the optimum solution of the angular velocities and accelerations of the joints. The problem would involve so many variables with trigonometric relations that a closed form solution would be impossible, still numeric methods would work fine.

With this modeling in mind, it is fair to explain Usain Bolt' supremacy by his extreme talent which were further honed by intense practice in operating these 4 joints. He can control his joints under changing track and personal condition so that his muscles apply just the right amount of force, that gives his joints a close to optimum acceleration. All of us can control our muscles so that we can walk, but he does it better, owing to practice and his talent. And this is the message of the Olympics, every one is talented in one aspect, and by training and setting your mind on it you can make wonders with your talent!

A similar explanation was given by an American professor and an ex swimmer for Phelps, which was mentioned in my previous post.

This explanation is related to the not so well known physical sense of Propricetion, which is the ability of the body to know where different parts of the body are, without the help of the other well known Aristolean 5 senses. I love the German word for it Körperwahrnehmung. Here is an article in German about it, which also claims this 6th sense might be the origin of our own consciousness.

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