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Could water chemistry be altered to make swimmers faster?

  1. Dec 18, 2016 #1
    At swim practice last week I started thinking about how the composition of the water was affecting how fast my teammates and I were able to swim. The mechanical properties of the water--viscosity, density, surface tension, etc.-- are what determine how much force swimmers are able to generate by pushing on it and how much drag they experience moving through it. And different substances, like surfactants in the case of surface tension, are able to alter those properties. So if it's possible to change water's mechanical properties by adding different substances to it, might it also be possible to develop an "ideal water" that would make swimmers faster?

    My initial guess is probably not, since any reduction in drag would result in a corresponding reduction in the force a swimmer would be able to generate by moving the fluid, and vise versa. (Am I correct in assuming that?) But then again, maybe there is some "perfect" set of properties that would strike an ideal balance between reducing drag and maximizing power?
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  3. Dec 18, 2016 #2


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    What would be the point? For fair competitions, all swimmers would have to be using the same modified water so why not just have them all use regular water?
  4. Dec 18, 2016 #3
    Just a hypothetical question about the "how's," not so much the "why's."

    Also, define "regular water." All pools have various chemicals for bacteria control, so it's not pure water by any means. And in other sports, namely track, this variable isn't even considered. Some tracks are much faster than others, and a few that are so fast that athletes, especially sprinters, are virtually guaranteed a PR. To make it truly fair there would have to be national rules governing the chemistry of the water in swimming or the track surface in running, but these don't exist to my knowledge.
  5. Dec 18, 2016 #4


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    Fair enough.
  6. Dec 18, 2016 #5


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  7. Dec 18, 2016 #6


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    If you increase the density of the water (by for example adding a lot of salt) that the swimmer would displace less water, ride higher in the water, and presumably, as a result have less drag.
    I'm not sure if it would affect viscosity which could affect the drag, but also the swimmer's propulsive force.

    In gymnastics, floor exercises are often (maybe always?) done on a surface of mats, but with a springy underneath, which gives them more bounce for flips etc.
  8. Dec 18, 2016 #7


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    In some styles rules say that you can't swim under water for longer than few strokes - from what I remember that's because swimming under water is generally faster.

    Reducing drag was researched by military, take for example a look here: http://www.dtic.mil/cgi-bin/GetTRDoc?AD=ADA397790
  9. Dec 18, 2016 #8


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    Oh yeah.
    They mentioned this a lot in the recent Olympics broadcasts.
    I also recall resistance is lower for submarines (completely underwater). Something about the surface of the water affecting drag.
    So this might negate my comment.
  10. Dec 18, 2016 #9
    I'm pretty confident that increasing density would make swimmers slower. IMG_4904.JPG
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