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tomtopo
December 22nd, 2006, 06:19 PM
The paddle wheel idea that pushing water straight would make something (a vessel) go forward, worked for paddle-wheel boats. Moving water straight back is a great way to show how drag forces can propel a swimmer forward.

In the early 70's the great swimming researcher, James E. Counsilman showed underwater video of great swimmers as they moved through the water. He showed that the hand moved in a sculling (back and forth) motion as it moved backward. Moving water with a hand that is pitched, toward the midline of the body from a position outside the shoulders, is a great way to show how lift forces (Animated Demonstration of Bernoulli's Principle) >
http://home.earthlink.net/~mmc1919/venturi.html#animation

It's important to note that Dr. Counsilman's underwater video showed that great swimmers entered and exited their hands near the same point. This demonstration showed that great swimmers were able to catch water more effectively than slower swimmers. Great swimmers moved their body over their hands vs. pushing water at high velocities past their bodies (swooshing water isn't good).

Doctor Counsilman also showed that every fast swimmer tended to look as if the hand and arm were moving over a barrel during the first quadrant of each stroke. This "over the barrel" motion is now called the catch or Early Vertical Forearm (EVF) position. The EVF is common and has been common among long course, short course, and open water championship swimmers. The under water video given at the end of this thread, shows all four competitive strokes from champion swimmers with an EVF.

There has been discussion about Drag vs. Lift forces and which one predominates in competitive swimming. It seems that not only lift and drag forces are common during fast swimming but eddie currents (turbulence all around a moving body), frontal resistance, air turbulence (on the hand and caused by the feet), and vortexes (tunnels of swirling air and water) behind the hand as it pushes water back.

Now, I'll try to give my two cents and show how these theories can be used to help you swim faster (not necessarily in order but I'll try).


Eleven coaches at the Senior Nationals in Irvine California were asked, "what would they teach first when coaching the freestyle. Nine of the eleven said the "catch" or EVF. The ability to reach and acquire a hand that is below the elbow as early as physically possible, will help you swim faster. The fact of the matter is that this skill is difficult to teach and was once thought of as a gift only talented swimmers could acquire. Today, not only do we know that's not true but new EVF equipment and training strategies are proving that anyone able to learn can improve their EVF.

Next, streamlining is another skill that allows swimmers to reduce frontal resistance. TI is wonderful at helping swimmers combat frontal resistance and thus helps them attain body position while swimming and in and out of walls that will help them swim faster.

Next, Lift vs. Drag. Drag can be thought of a couple of positive ways. Drag is the ability to leverage water or hold it at any given time. The time however when drag forces are exerted can be help or hinder a swimmer. So, knowing when and where to leverage water during the stroke is critical to swimming fast.

Most swimmers exert pressure with a straight arm in the first quadrant of the stroke. This pressure lifts the body up and not forward, so the use of drag forces during the transition from the fourth quadrant to the first is not good according to this coach. There has been more than a few good coaches that contend otherwise so I'll let you decide. Let me use the example of someone with "swimmer's shoulder" putting on the largest set of hand paddles and trying to swim. The injured swimmer would be exerting pressure at the start of the stroke and the fulcrum area would be so close to the shoulder (head of the humerus) that more injury is likely to occur. I know this is a gross example but swimmers who love to feel that pressure at the start of their stroke aren't developing good habits (just my opinion)

Next, as the hand enters the water, just outside the shoulder it moves into an EVF for good swimmers, a late vertical position for mediocre swimmers, and the slowest swimmers would be so late, they would drop their elbows so the hand catches very little water.

After an EVF position is reached the hand begins to gain unwanted vortices of turbulence behind it and must move toward the midline and into water that is more still so it can maintain drag forces. This is where the appearance (my opinion) and wrongfully so, that sculling or lift forces begin to contribute to freestyle propulsion. I believe drag forces play a predominate role during the freestyle, backstroke, and butterfly. I also believe that drag forces play more of a propulsive contribution during the breaststroke than most coaches are lead to believe. So, if you want to swim faster, work to maintain an EVF and keep leveraging the water by moving the leveraged water into still water via a sculling motion. DO NOT scull toward the midline too quickly and most definitely not until an EVF is acquired.

Next, the need to remove air from the hand is important and this process occurs during the transition from the fourth quadrant to the first. At this time I should describe the quadrants and what each includes.

Each competitive stroke can be separated into various parts. If we use four parts or quadrants we can dissect each stroke into a front quadrant where propulsion occurs, a second quadrant where the finish or completion of the stroke occurs, a third quadrant where the recovery is initiated, and the fourth quadrant where the recovery makes the transition to the entry.


An over the water recovery during the breaststroke should be encouraged when the swimmer effectively cleans all the air from their hand before the begin pulling in the first quadrant. When swimmers show coaches that they can't effectively remove air bubbles from their hand, they should be told to use an underwater breaststroke recovery.

Moving water into the wall can be attributed to the movement of a swimmers body and the turbulence that body brings to the wall. I tell swimmer to take the width of their body and double it (really a little less) and during a turn, they should get under that distance to avoid the turbulence and resistive force they brought to the wall. So getting deep during a turn is important.

Next, the distance the hand moves toward the body during the sculling motion as it moves backward and to the finish of the stroke is important. The eddie currents moving around the body are currents and that's not "still" water. So, if the hand moves too close to the belly or the hips, they reduce leverage or the ability to effectively leverage water. I tell swimmers, especially butterflyers to scull away from their hips as they finish their stroke.

I will often catch novice freestylers moving their hand to quickly toward the mid-line and too close to their body.

I've enjoyed talking about theories and applications of those theories as it relates to faster swimming. I'd enjoy to talk more but I've decided to write an article on the topic of propulsion and hope to have it worthy of this forum.
Good luck to you and to you in the New Year. Coach T.

islandsox
December 22nd, 2006, 07:22 PM
Coach T,

I so enjoy reading your findings on the constant search for helping swimmers to swim faster with the best possible technique possible.

I, too, learned EVF but learned it from George Haines and Don Easterling. And they both used the example of swimming crab-like or over the barrel. Drills were setup to help us swimmer swim EVF (catch) without harm.

When you discuss lift vs. drag, one Olympic swimmer comes to mind. Mary T. Meagher. She was a butterflier and held one of the most long-standing records of all times: 1979-1999. The one thing she was infamous for was the ability to be able to constantly change her hand/forearm position as drag increased or released. She spoke of this "feel" for the catch more than anything else. This, more than all of the records she broke, was the basis for her success. The ability to "feel" when changes needed to be made before they needed to be made.

Now, this is out of my league now, but I understand what she is referring to. But as more swimmers who learn how to feel the water as pressure changes, it will enlighten them to experiment with hand/forearm/stroke changes. And in open water, changes are happening all the time.

I always enjoy your threads. Keep them coming for I am listening and as I am listening, I am also reminiscing.

Donna

Allen Stark
December 22nd, 2006, 09:08 PM
Coach T,that was one of the best,concise descriptions I have ever read. I think lift forces are somewhat important in the insweep of breaststroke pull,but I agree not as important as was taught a few years ago when the "windshield wiper" drill was in vogue. I used to think lift was predominant in the whip kick,but I am re-thinking that and am experimenting with different angles of pitch of the ankles. What do you think about optimum foot position in breast.

tomtopo
December 22nd, 2006, 11:04 PM
One of my Christmas wishes is to be able to sit down after a dinner with my forum colleagues and simply chat like this. I'd love to see all of you in person!!! Anyway, back to the thread.

The ability to maintain constant pressure on the water is indeed important and Olympic swimmers like Mary T. had it. I think everyone can keep working to improve it. I'd like you to try maintaining a stiff and less flexible wrist throughout your stroke and tell me what happens. It's extremely difficult to maintain a stiff (less then a 12% bend throughout the entire stroke cycle) but try it.

Swimmers assume that by bending or flipping water toward their feet or bending the hands at the entry of the stroke, they're setting themself up for more power. On the contrary, actions have reactions, and when you bend your wrist anytime at the beginning, middle, or end of the stroke, your feeling of power that you thought you gained was lost when you re-bent your wrist.

A good example of what I'm talking about is when backstrokers bend their wrists away from the mid-line in an effort to "scoop" water. If scooping makes them feel great at the beginning of the stroke (not a power phase anyway) guess what happens when they must straighten the wrist out when they're catching water during the power phase? -- They lose pressure and leverage.

So, keep pressure on the hand my reducing as much of the bend in the wrist as possible. It's not easy if you've been pulling over 16,000 times a week for ever but you can try and I think you'll feel a significant difference in your stroke and drop time as well.

I believe the acquisition of an EVF can be a learned experience that everyone can enjoy. I don't thing eveyone will be an Olympian but for goodness sakes, I certainly believe a significant improvement can be achieved by everyone without increase yardage (training smarter not farther is my motto or a motto that I stole from someone - it's a good one).


The optimum angle of the foot in breaststroke will be determined by the flexibilty in the knees and ankles. Drag forces are predominately at work here and the ability to get the feet as far away from the knees while maintaining a flat foot parallel to the opposite end of the pool, allows more water to be pushed back and thus power. The width of the feet from the knees is important because pushing water back increases the vortex and to reduce the vortex (on the opposite side of the bottom of the foot) it must move in an eliptical pattern (if the knees are really close together and the feet really far apart the pattern looks more round). I hope you get it. In other words, if you're really flexible you can keep your knees closer and feet farther apart and it'll allow you more power.


I can go on and on but I won't unless you have another question or I haven't been specific enough. I enjoy answer questions and I don't consider myself an expert but I've studied from the experts and am regurgitating what they've told me. I don't believe everything the experts tell me but when they tell me things that have a logical and scientific foundation, I'll go with it. Take what I'm saying with a grain of salt. Please keep in touch, and Happy Holidays.