![]() ![]() The result is that the hand follows the clock to the 3 o’clock position, moving both downward and forward. The swimmer begins the pulling motion by pushing the hand downward in order to reverse its direction and push it backward. Since the swimmer’s body is moving forward, as the hand enters the water, the hand will move forward also. If we consider the circle as a clock, the hand would enter the water at 12 o’clock. In shoulder-driven freestyle technique, with a relatively higher stroke rate, if one were to map the pathway of the pulling hand from the side, relative to a fixed point in the pool, one would find that the hand moves in nearly a perfect circle of around 2 feet in diameter. Since water is liquid, not solid, in order to create propulsion, the hand or foot needs to be moving backward relative to the water. Some understanding of fluid mechanics is therefore necessary to understand how propulsion is achieved within these two different environments. The propulsion of a swimmer that is derived from the hands and feet differ in that the hands are moving through water that is essentially still (static fluid), while the feet are moving through water that is flowing (dynamic fluid). High energy coupling motions can significantly increase the propulsion of a swimmer in all four strokes, as well as on the start. Neither motion produces any propulsion by itself, but when timed or coupled with a propulsive pull or kick, either motion can make either force greater. Two examples of coupling motions in freestyle are the rotation of the body and the recovery of the arm over the water. ![]() In addition, the propulsion from the kick and pull can be influenced by other motions of our body that produce no propulsion at all. More specifically, except for the up kick, where the entire lower leg and foot can create propulsion, nearly all of the other propulsive forces (down kick and pull) occur at the feet and hands. Outside of the starts and turns, the propulsion forces of a swimmer are derived purely from the kick and the pull.
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