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thewookiee
October 22nd, 2008, 09:03 PM
The talk lately has been about getting a "EVF" at the front part of the stroke. With so much focus there, is there still a slight/any/some accleration(sp?) of the arm after it achieves an "EVF" or should we try on keeping the arm as still as possible until the finish

geochuck
October 22nd, 2008, 09:37 PM
Some believe we apply pressure but is it acceleration?

Are we actually moving the hand and forearm thru the water?

Are we just grabbing the water and holding on to it?

Does the forearm move very far with the pressure applied?

tomtopo
October 24th, 2008, 03:48 PM
I'll bite ---

Let’s use a paddle /oar and a boat as an example. To start the boat moving nearly any movement of the paddle backward will do the trick. To accelerate to the fastest speed, getting the paddle into a vertical position as soon as possible and maintaining the vertical position as long as possible will help accomplish that task - TO A POINT. When water begins to travel around the paddle a vortex behind the paddle creates a force that negates some of the drag force. To maintain optimum drag force on a paddle that’s moving backward the paddle must move toward or away (or both) from the boat so the vortex can be reduced. So, the length and size of the oar will determine how deep and the amount of pressure the oarsman can apply to it. How much leverage or force that can be applied by the oarsman is dependent and their range of motion, strength and skill (keeping drag forces at their highest potential).

So a swimmer who can apply the most force for the longest time with everything else being equal will swim faster. This means that swimmers who can get their forearm / hand into the earliest vertical position with the most force and maintain that position over a longer distance will swim faster. The vortex and turbulence created behind the hand as it moves backward must be combated by moving the hand into less turbulent or “still” water (pitching the hand no more that 45 degrees / sculling / lift force accomplishes this task) The EVF starts in the first quadrant and moves into and out of the second quadrant (the 3rd quadrant is when the hand exits or recovers and the 4th quadrant is where the hand enters the water after the recovery). It gets more complicated than this but it is what it is.

Success consists of going from failure to failure without loss of enthusiasm.
Winston Churchill

abc
October 24th, 2008, 03:56 PM
Dude, forget the sci-fi and just swim.

geochuck
October 24th, 2008, 03:59 PM
Tomtopo I knew you would have a good answer.

thewookiee
October 24th, 2008, 04:45 PM
Dude, forget the sci-fi and just swim.

Just swimming is fine at times but it is always good to know the current thinking. Otherwise, just swimming doesn't help one improve or help someone that is in a position to help others improve.

daveindc
October 27th, 2008, 09:37 AM
I just wanted to chime in and say EVF works wonders. I just started doing it a week ago and dropped my 50 free from 25.20 to 24.45.

pwolf66
October 27th, 2008, 10:54 AM
Dave,

Sorry I didn't chase you down yesterday. Hopefully we'll meet up somewhere down the road and introduce ourselves.

daveindc
October 27th, 2008, 11:00 AM
Sounds good, Paul. Looks like you had some pretty good swims yesterday.