Friday, September 3, 2010

Teck Beng's Question on body rotation

Hey KK, thanks for letting me write in your blog.


I would like to take this opportunity to post one question that I have been thinking for a while. It’s a little complicated to do this in facebook or SMS, explaining in person lacks the video and pictures, so I thought blogging about it is best, and the rest can read and think about this as well and offer their views.


So, my question is about body rotation, or body roll in freestyle.


I remember you say this before:

“…the body should rotate from side to side, about 45 deg. And this rotation should be the whole body, from the shoulders to the hips to the legs and toes. Basically, think of the body as one single plank, and they should rotate together.


I think this is pretty much the universally accepted method….here’s one blog talking about the importance of body rotation (whole body).


http://effortlessswimming.com/freestyle/technique-why-it-should-not-be-front-crawl/


and I quote:

“Your shoulders should rotate with your hips and should move at the same time. It can work best by concentrating on moving your hips first and your shoulders second….”


I was thinking….ok this must be correct then…(KK, I don’t double check everything you say, I only look up things that I find it hard to do…like this one)


But to my surprise, I also found this….


http://effortlessswimming.com/freestyle/body-position-in-freestyle-swimming-technique-video/


and I quote:

“To move more easily through the water in freestyle, you must rotate your shoulders. No doubt you’ve been told to rotate in the water, but too often swimmers are told to rotate the entire body as they take each stroke. This is incorrect. Elite swimmers work on keeping their hips relatively still with only minor rotation….”


Bloody hell, these 2 posts are both from the same website…


I got a little excited as someone thinks that body roll need not extend below the hips and the hips and legs can remain more or less flat.


Surely, the next thing is to look for video confirmation.


Here is Phelps:

http://www.youtube.com/watch?v=ax77_hHq9Dc


He seems to rotate (below hips) more on the breathing side. The other side is much less, surely less than 45deg


Now, to be clear, I agree that shoulder rotation is important because:


1) helps your recovery arm to clear the water surface without suffering a dislocation in the process

2) reduce the total projected frontal surface area, reducing drag

3) Help breathing, you don’t have to turn your head like an owl to take in a lung full

4) As the shoulders rotates, to keep the head still, the neck needs to turn in relative to the shoulders…this prevents stiff neck


But how many of the above 4 points can be said for hip and below hip rotation?


From what I can imagine, rotating the hips and everything below will


1) use more energy

2) complicates the kicking (at least I find it so)

3) Disturbs the water more.


So, my question: Is the question on body roll a settled issued in freestyle swimming or is the jury still out on this one?


Unlike the straight pull and the S pull, I think the argument is pretty much settled, but for the rotation, seems to me there a still much controversy. Maybe we can all look at this critically and not confuse what is familiar with what is necessary.


Comments please.

3 comments:

  1. this is an easy one. Using the hips to help drive body rotation involves the entire core, which is much less prone to fatigue than the shoulder muscles. Nearly every one swims with too much "arm" and not enough "body". You can debate the very fine difference between the angle of rotation of the shoulders & hips in phelps video that you post...but do you think that your body can tell the difference between a 35 degree rotation of the hips and a 40 degree of rotation of the shoulders? It takes less energy to roll the body when you can tune into using gravity to help shift weight from one side to the other..and when that happens the shoulder rotation takes no energy at all.

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  2. As I update myself, I have a final conclusion for this discussion.

    And I think I already shared it with you guys personally. Since Tri coach mentioned it here, I'd just post it here to share what we studied.:)

    I think the technically correct way to answer this is to go through the 2 main objectives of a body roll.

    Quoting SWIMMING FASTEST,

    1) body roll is for firstly, the better threading of a straight push back phase of the arm stroke which leads to..

    2) A body position more primed for easier recovery of the arm without causing the humerus to get internally rotated or jammed into the shoulder socket.

    Large amount of Body roll essentially causes lateral drag. Just take a kickboard, put it on the surface and flip it side to side continuously and you'll see the "turbulence" it creates beside the board. 

    But too little of it means those who have less flexibility in the shoulders can't recover the arms without dragging it under the water.

    Thus I conclude that the body rotation should be individually set to minimum according to the swimmer's shoulder flexibility and his/her push back angle of the am stroke.

    If there is a need for body rotation, it has to be coordinated and thus the term "driving from the hips" comes because that's the mid point between the torso and the legs. Moving the hips side to side instead of starting the movement at shoulders help reduce the "lag time" that the legs has to follow. However, if you keep your body in a plank position when you swim, it doesn't really matter where you start turning first as long as the whole body from top to toes moves together.

    Lastly, we have to note that body rotation does not contribute to power increment because unlike land sports's corking motion(e.g baseball bat swing), there is no point of anchorage and the body is essentially moving through the medium as the pull and hip rotation occurs. 

    Cheers
    KK
    Enquiry@sapphireswimming.com

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  3. Oh yes, last add on: body roll has to be done w the whole bod as a plank because twisting of torso and legs also cause drag.:)

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