14 janv. 2013

SWIMMING IN TRIATHLON II



It is refreshing to know that numerical research is behind 15 years and not further behind.
Emphasis on technique started when coaches and athletes decreased training from 30k a day that the elite swimmer used to do, to 15 a day.  We cut it in half the time training per day; but athletes needed to be smarter, better educated and clever to stick with the technique program.  I will emphasize technique using the principle of the airplane.  Do we have anything faster and better in the earth for moving than the airplane?

Drag
Figure 6 Movement through water is resisted by the water immediately in front and around the hydrofoil. This water resistance is called drag. Drag force always acts in the direction of flow. Due to its shape the water speed above the hydrofoil is greater than below. The pressure above the hydrofoil is less than below, resulting in a net upward force called lift. By definition, lift acts perpendicular to drag. The nature of the lift force is similar to that experienced by an aircraft wing.

Interestingly, 15 years back, Glenn Mills spoke of swimming with the “body,” instead of swimming with the arms and hands.  This is huge difference.  See the explanation of Counsilman (coach and researcher with numbers).  The nature of the lift force is similar to that experienced by an aircraft wing. As Counsilman (56) explained: "A wing provides aerodynamic lift through the camber (curvature) of its surfaces. Because the upper surface is more highly cambered than the lower surface, the air moving over the top surface is forced to move more quickly. This results in a lower pressure on the upper surface as compared with the lower surface and results in aerodynamic lift (Bernoulli's Principle)". (p. 61) Thus the pressure differential results in a lift force directed at right angles to the line of motion of the propelling surface (see Figure 6 and 7).  
It is clear to me that the plane is the entire body and by changing the shape, (technique and position) of the body we can get the effect of the lift force.  By using the lungs as buoys to keep the weight in front of the subject (swimming downhill), the lift force IS WHAT MAKES THE SUBJECT MOVE FORWARD, it is just like the plane.

Where are the hands in this equation?  The hands are used to keep the weight in front as a support to keep the body moving forward.  This is what is called swimming with the core.  Unfortunately, the direction of research took a different turn:  Subsequently, numerous papers were published (57-63) to support the notion that the total propelling force acting on the hands is composed of both a lift and drag component.
They did not notice that the core was the part of the body doing the lift force.  Researchers saw just the hands because they did not how swim!  That is problem with research done by somebody not familiar with swimming or the sport they research.

Why not to swim like an airplane!  It is just a matter of learning the proper technique that gives that advance.

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