Friday, April 11, 2008

A Beginning and an Advanced Player Are Very Different!

To look at them both, the eye would see that they are demonstrating the same contributions to the pedal stroke. Nothing could be further from the truth!

The effects of acceleration and deceleration of the many segments and how they are traveling are, for the most part, so fast that the muscles cannot keep up, let alone accelerate the segment further. Nor can the brain process the information to better understand the axis or the acceleration of the segment.

Think of a kicking pattern or a throw-like pattern in which the proximal segments initiate the movement forward, causing a lagging back of the distal foot segment. The knee extensor muscles and the surrounding tissues prevent the leg and foot from lagging back too far. The pattern of motion is consistent with the "link" principle.

We know how important the hip muscles are and in the advanced player they put out, perhaps, 90% of the work done by the leg muscles. The beginner attempts to control the distal part of the stroke. This is a very delayed feedback process, rather than being more proactive. The hip muscles are responsible for both the thigh's motion and the knee's extension.

The knee is extending so rapidly that the knee extensors are incapable of exerting a forceful contraction due to their inherent force-velocity limitations. Meaning, the distal segments are also traveling so fast that the muscles cannot keep up or provide good feedback to your brain...as in the case of being on a trainer and adjusting the distal segment to record power, let alone accelerate or refine the segment further.

The acceleration of the thigh flexion about the hip joint should take place as long as possible because the acceleration of knee extension tends to decelerate the thigh segment. Your saddle location is key. Thus the longer the thigh can accelerate, the greater the angular velocity of the foot as it is attached to the pedal e.g. of the foot when it reaches a ball.

As the leg accelerates, the thigh either begins to decelerate or its acceleration is reduced. This is due to the hip joint that acceleration moves about.

If you care about getting this right, go see one of our Wobble-naught & Myo-facts sEMG/Dartfish dealers!

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