ABOUT SWIMMING…

FROM Bernoulli TO … Counsilman

Daniel Bernoulli (1700-1782), was a Swiss mathematician and physician interested in fluids and gases who was interpreted by Dr. J. Counsilman in Science of swimming, Indiana, 1977, USA. Starting from Bernoulli’s laws he has observed that the propulsion effect of an airscrew’s blades is alike the correct paddling moves done by a swimmer (each of the blade drives on short distances great volumes of water, air, the same as the paddling movements in swimming).

He also remarked that each paddling is composed of the elements of the moving airscrew – the palms try to apply the force on short, lateral directions in order to get/travel through greater water volumes and this is how it gets a greater support from it. When the force is being applied on a long distance the water will “run out” from the palms and the volume of the water moved will be less and though, inefficient.

In this model you can also find the relation of 3^rd degree levers, which are specific for biomotricity. As a fact, the swimmer is supported by the water and this is how he advances – he doesn’t move more water by pushing it contrary to the advance direction!

Finally, though it seems unexpected, the correct paddling move is not a linear movement but a sinusoidal one, as you can see from the graphics below.

(*graphics Science of swimming, J. Counsilman, Bloomington, Iova,1974)

[ each swimming technique has an arm movement to looks like the airscrew’s movement]

These images show two old interpretations of the paddling movements:

In the first one, the composition of the momentum is the same as the airscrews used in old boats:

(the speed sector is very short while the floating component is big);

In the second one, you can see a caterpillar movement style – like a chain track (where there is no gliding moment but there is a prolonged traction moment). Both of the representations are inexact and reflect the way that swimming was thought 50-100 years ago.

(*graphics Science of swimming, J. Counsilman, Bloomington, Iova,1974)

J. Counsilman’s studies shown up that in fact, paddling movements are parts of helicoidal movement – airscrew movement. This is how you can explain the 3^rd degree levers law (used by human, animal biomotricity) and you can understand that paddling becomes efficient as far as great volumes of water are being moved – on short distances (maximum of efficiency).

(*graphics Science of swimming, J. Counsilman, Bloomington, Iova,1974)