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mj_mcgrath
December 22nd, 2006, 10:55 AM
A Learning Channel special on Lance Armstrong showed how he spent hours perfecting his aerodynamic position on the bike. Computers would analyze the drag caused by Lance's different positions on the bike and the bike itself(i.e.his body caused 2/3 of the total drag). All of this testing to save maybe 1 or 2 percent drag. Of course, in the Tour De France the few seconds time differential could be the difference between a win or loss.

So how could you test your own hydrodynamic position in the water and would it be worthwhile? I imagine one could push off the pool wall and try different positions of head,arms,torso,legs, and feet and find the ONE position that allows you to go the farthest. Persumably, that would be your most hydrodynamic or slippery.

Or, I suppose if you had an Endless Pool, you could tether a swimmer to some kind of force gauge that would measure the energy required to keep the swimmer stationary at a certain flow level. Then try different positions of head, arms, torso, legs, and feet to find which position requires the least amount of force to stay stationary.

Intuitively, one would think that a head down, straight torso, hips, legs, and pointed toes would be most hydrodynamic but not necessarily so.
How does that hydrodynamic position change when a swimmer breathes. Again, is one position more slippery than another and is it different for everyone? How would you test it?

I don't have answers--only questions. Any one aware of studies or empirical data?

KaizenSwimmer
December 22nd, 2006, 12:37 PM
So how could you test your own hydrodynamic position in the water and would it be worthwhile?

Quite worthwhile. Simple tests include stroke counting, swim golf, and swim golf with RPE or HR factored in.


How does that hydrodynamic position change when a swimmer breathes. Again, is one position more slippery than another and is it different for everyone? How would you test it?

I don't have answers--only questions. Any one aware of studies or empirical data?

Good questions indeed. I don't have studies, only the results of many empirical experiments with myself and others.

Which stroke does your breathing question refer to. Breathing without affecting hydrodynamic position is far more challenging in free than in other strokes. Certain focal points have proven helpful:
1) Keep top of head down, or head and spine laser-aligned, as you rotate to breathe.
2) Breathe with more body roll than head turn.
3) Follow your shoulder back with your chin.
4) "Get taller" as you rotate into your breath. "Stay tall" as you return back to neutral -- but without introducing a hitch into your rhythm.

Those are my primary. Even more basic -- not increasing hydrodynamism, but allowing seamless breath-and-return -- is active exhale and no interruption of air exchange.

Open water introduces its own set of considerations. And then there are the Short Axis strokes.

geochuck
December 22nd, 2006, 12:46 PM
Glad to see your are back, sorry that I missed the debate on theories. It did look interesting but thought the going was rough. I do like to read all of your posts.

The Fortress
December 22nd, 2006, 12:50 PM
Glad to see your are back, sorry that I missed the debate on swimming theories. It did look interesting but thought the going was rough. I do like to read all of your posts.

Hey, "swimming theories" was an interesting thread while it lasted. Are you calling us lawyers and OW swimmers and Caped Dudes "rough?" Since you are now doing fly, I might be up for a little race down in Mexico. I like reading Terry's posts too. One doesn't always want to read the conventional stuff.

George, you're going to crack 2000 posts soon. I think your posts are generally shorter than Terry's though, so his post # should really be doubled to reflect the length and depth of analysis.

Allen Stark
December 22nd, 2006, 01:40 PM
At the Olympic Training Center they measure your resistance in the flume by having you tethered to a resistance gauge(just like the endless pool idea.)It's great because you can see how small changes in body alignment can make big differences in streamlining.

scyfreestyler
December 22nd, 2006, 02:48 PM
I have been paying a bit more attention to my streamlines off the wall and it has made a big difference in how far I have to actually swim. The beauty of something like this is that regardless of whether or not you improve your conditioning or actual swimming speed, this "skill" can shave time off of your swims. A good streamline will probably allow you to swim faster as your stamina will be less taxed due to a longer period of time spent underwater.

Reducing resistance is every bit as important as increasing propulsion.

islandsox
December 22nd, 2006, 03:23 PM
Allen,

Yeh, I got to experience one of those flume's; all went well until I turned my head to breathe; that tether got a little slack in it.

And SCYfreestyler, I'd give anything if I had a thousand walls to push off of on my 18 miler, and since I can't swim underwater like a fish, I am, sadly, left with a very long stroke length AND propulsion. Doing both for 18 miles should prove for an interesting story at most.

Donna

Superfly
December 22nd, 2006, 03:43 PM
Referring to an interesting article at http://www.breaststroke.info/waynestretch.htm where these pictures are taken from.
/Per

KaizenSwimmer
December 22nd, 2006, 05:49 PM
I'd give anything if I had a thousand walls to push off of on my 18 miler

One of the major factors that differentiates OW from pool swimming is that absence of walls. It's ALL swimming without the few seconds of recovery every 25 yds or meters. That makes economy and relaxation a huge difference-maker.

I'm working on an article on adjusting technique for OW for USMS Swimmer magazine. We tested all the theories and techniques in an OW camp in Eleuthera last week. I related in another thread how all 19 swimmers in the camp completed a 2.5 mile open ocean swim after only 1 1/2 days of instruction, and most of them were true novices, so I am most hopeful that this article will encourage many pool-only swimmers to give OW a try. And the pix we took are out of this world. I hope they'll have space to publish some of the "non-technical" ones to make OW irresistible.

I'll probably post a few more snippets here for reaction as I get deeper into it.

SolarEnergy
December 22nd, 2006, 06:59 PM
One of my spiritual fathers (though he doesn't know he had me as his son though... anyway.... complicated.) invented a tool in '92 to measure swimmers efficiency (http://www.patentstorm.us/patents/5391080.html)

I believe hydrodynamic efficiency was part of the "things" being measured.

I have never seen it. I only remember that everyone would laugh at him in his back. I think he invented that at least 20years too early.

Swimming community isn't there.... yet.

knelson
December 22nd, 2006, 11:29 PM
Yeah, a flume or endless pool would be very useful in evaluating the aerodynamics of your streamline. And, you're right, they'd just need to attach you to something that would hold you still and could measure the amount of force. This is exactly what's done with airplane models in a wind tunnel.

Trying to evaluate how aerodynamic you're stroke is would be much more difficult.

Larry_55
December 23rd, 2006, 10:38 AM
) Follow your shoulder back with your chin.
4) "Get taller" as you rotate into your breath. "Stay tall" as you return back to neutral -- but without introducing a hitch into your rhythm.

It was great to see these principles encouraged by much more experienced swimmers than myself. I had very little in the way of formal coaching in my technique and came to this basic technique more intuitively than by way of instruction.

poolraat
December 23rd, 2006, 11:42 AM
One of the major factors that differentiates OW from pool swimming is that absence of walls. It's ALL swimming without the few seconds of recovery every 25 yds or meters. That makes economy and relaxation a huge difference-maker.


Terry,
Just out of curiosity, are you able to quantify the difference. I've done 3 lake swims (2-1 mi. and a 2.7 mi.) and I've noticed a difference of about 5 min. or more / mile but I'm not sure if it's because of the time gained on turns or if it is just my inexperience in OW swimming or both. And should there be that much of a difference?

SolarEnergy
December 23rd, 2006, 11:43 AM
One thing I might add about hydrodynamic. It's part of my coaching philosophy.

The one big difference between aerodynamics (in cycling for instance) and hydrodynamics, is that it's much easier to get a natural spontaneous feed back helpful to auto-analyse our hydrodynamic efficiency while swimming.

I can't really coach a cyclist to *feel* the drag resistance imposed by the wind on the upper body, or the bike or anything.

But I can coach a swimmer to develop this *feel* for hydrodynamic efficiency. Some have already pointed out the stroke length as a good indicator of this efficiency.

I'm absolutely convinced that good swimmers, in fact most swimmers (intermediate to advance) can also juge the amplitude of their own "acceleration/deceleration/acceleration/deceleration" pattern while swimming. It's also possible to develop this *feeling* of accute drag resistance experienced by most parts of our body. For instance, a good breaststroker can feel more or less resistance during the leg recovery, and will naturally favor a position involving less resistance.

One simple drill to learn to listen to these feelings? Swimming with a pair of pants and long sleeves sweather for a while, and then removing the cloths.... well you may want to keep a bathing suit on :joker:

tomtopo
December 23rd, 2006, 02:34 PM
As a member of a group of coaches, invited to Colorado Springs, we saw how scientists used the swimming flume at the Olypmic training camp. There certainly should be a great deal of data on the hydrodynamics of a swimmer. You can contact the Olympic Training Camp and ask them who you might talk to on the subject of research finding from the testing they do with the flume. I think they'd be glad to help you. Go to this site at the end of this article for contact information.


Reaching SUCCESS THROUGH SCIENCE
at the International Center for Aquatic Research

United States Swimming is proud to announce the Success Through Science program, which is aimed at athletes of all abilities who are interested in improving their swimming performance.

As an adult athlete, you might feel that improving your swimming has been difficult and frustrating, or that your best days in the sport have passed you by.

But at United States Swimming, we see these years as some or your best. No matter your age, there will always be that untapped potential. And whether it's an adjustment to your stroke, your training program, or how you mentally prepare for competition - we are here to help you succeed.

That is why USS has created a program specifically designed to help swimmers continue to excel even after those youthful years are just a memory.

United States Swimming and the International Center for Aquatic Research aim to help swimmers reach peak performance by unlocking the mystery of the science aspect of the sport.

The ICAR is a unique facility which combines both "one of a kind" laboratories and swimming flume with professional staff devoted to swimming science. ICAR scientists asses swimming performance in order to assist athletes - at all levels of the spectrum - achieve greater success in the pool.

Participating swimmers are taken through a battery of tests to assess their strengths and weaknesses in the psychological, physiological and biomechanical categories.

Following this data collection, an ICAR scientist will interpret these results and make recommendations for each athlete for both training and competition.

For more information, please contact Tricia Downing, Marketing Coordinator at: tdowning@usswim.org or at 719-578-4578.


Let me continue, --

When a swimmer is taking a breath, the arm is in the most powerful phase of the stroke. A common error among beginning swimmers is taking the breath too early in the stroke or too late. The following articles on other aspects of streamling are interesting. Good luck to you and Merry Christmas, Coach T.

Here are a couple articles on the subject that are interesting.

http://www.usms.org/articles/articledisplay.php?a=139

http://www.evanscoaching.com/documents/Swimming%20Momentum%20and%20Arc%20Continuum%20-%20Evans.pdf

http://www.fluent.com/about/news/newsletters/04v13i1/a1.htm

nkfrench
December 23rd, 2006, 05:28 PM
I thought USA Swimming dismantled the flume at ICAR/Colorado Springs recently.

I got videos swimming in it back in about 1995 at a Masters swim camp when I was in good shape and going to meets.

geochuck
December 23rd, 2006, 05:50 PM
Forget Hydrodynamics and learn to swim. Most of the swimmers here will never be able to put it to good use. Swim streamline apply force when you get to the catch and finish your strokes you will be fine (nothing is effortless). Use a good 2, 4 or six beat kick. Take advantage of the push off on your turns.

KaizenSwimmer
December 23rd, 2006, 05:54 PM
Terry,
Just out of curiosity, are you able to quantify the difference.

I haven't tried to quantify it. I keep pool swimming in one mental category time-wise and OW in its own category without trying to compare one with the other by any conversion factor.

But I can vividly recall my first LCM training experiences in the late 60s when I had a rapid churn-it-out stroke. I dreaded 400m or 800m repeats because my arms would get so much more fatigued from having to go 45 meters between arm-resting pushoffs, rather than 20 yds, nearly a 250% increase in distance between pushoffs. Move from a 50m pool into a mile of OW and the unbroken-swimming distance increases by a huge factor.

Now I LOVE LCM training -- second only to OW. The frequent interruption of my flow and rhythm in a scy pool is irritating

Dominick Aielloeaver
December 25th, 2006, 03:07 PM
Tomtopo. Tom Read your article hydrodynamic. I thought it was real comical. But informative. I only swim freestyle. I like distances swims ,since I am a very slow swimmer. I once did a swim in Flaggstaff AZ. It was in a 25 YD. pool. The longest race was 100 yds. So I told my wife man what short races these are. Not realizing we were up 7000 ft. But while doing the one 100 Yds. On the thrid lap I was sucking wind and barlleymade the finish. Merry Xmas DOM.:woot: :groovy:

Redbird Alum
December 25th, 2006, 07:41 PM
I was surprised no-one mentioned the overhead draglines they used to use at the Colorado Springs training facility. By dragging the swimmer through the water at speeds approaching Olympic pace, the swimmer very quickly understood where they were not streamlined. (similar to putting your hand out the window of a car at 60mph)

Does anyone know if this is still being used in training Olympic hopefuls?

Dolphin 2
December 26th, 2006, 01:05 PM
Forget Hydrodynamics and learn to swim. Most of the swimmers here will never be able to put it to good use. Swim streamline apply force when you get to the catch and finish your strokes you will be fine (nothing is effortless). Use a good 2, 4 or six beat kick. Take advantage of the push off on your turns.

Very good advice Geochuck.

Being in the science and engineering field, I have some experience with the subject of Computational Fluid Dynamics (CFD) and it is an extremely expensive process that it is economically limited to high end industrial products. Even for hydrodynamic modeling of a simple industrial water pump, the cost of running a CFD program can run $100,000 per second!

Trying to use CFD to analyze swimming techniques is rather superfluous as human behavior cannot be managed by engineering methodology and the cost can’t be justified using an industrial productivity analysis either. Accordingly, I have commented on this questionable research about using CFD with regard to the so called “high tech” suits.

Http://forums.usms.org/showthread.php?threadid=6161
In addition to their obscure purpose, the idea of swimming with your body covered with water proof material is antithetical to aquatic sports and ruins the sensation of being in the water. :mad:

I’ve often thought of “sports technology” as a more a way of glorifying athletics and provide it with some illusory importance in the science/engineering world. Frankly, I wish we could let swimming (and other athletics as well) just be for fun and we could get rid of this hyper competitive techy attitude.

Happy Holidays & Happy Swimming

Dolphin 2