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Medical Isotonic drinks

  1. Sep 6, 2009 #1
    Hi guys, i am not sure if its here i should post this but couldn't find a better category.

    Just wondering, after exercising, we're often thirsty and drinking isotonic drinks is better than drinking normal water, why is that so?
  2. jcsd
  3. Sep 6, 2009 #2


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    During exercise you loose electrolytes through transpiration, by drinking isotonic drinks with electrolytes you restore your body's supply. Also, the isotonic drink will maintain the osmolality of your blood, so that less urine is produced (making the rehydration more effective).
  4. Sep 6, 2009 #3
    Then would normal water with additional of salt have the same effect ?
  5. Sep 6, 2009 #4


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    Bottom line is if you're engaging in light to moderate exercise for under an hour or so, an isotonic sports drink is unnecessary. There is also evidence that overconsumption of sports drinks (exacerbated by their pleasant flavor) can contribute to excess hydration resulting in a potentially dangerous condition called hyponatremia:


  6. Sep 7, 2009 #5
    Thanks for the info :)
  7. Sep 7, 2009 #6


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    If it usually a good idea to add some juice to the water to give it some taste. The reason is simply that it will make you drink more; most people will simply not drink enough fluid to get properly re-hydratet otherwise.
    The fact that sports drinks make you drink more (and sometimes even make you a bit thirsty) is one reason why they are often more efficient than water.

    But other than that I agree with what has been said above; unless you are exercising for over one hour isotonic drinks are probably not necessary. The one exception might be if it is really warm and you are sweating a lot.
  8. Nov 19, 2009 #7
    Thanks. very helpful post. I read a few of your other posts and they all helped me.
  9. Nov 19, 2009 #8

    Andy Resnick

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    Not yet mentioned, there is a sodium-glucose transporter. So, in order to more efficiently absorb glucose, it helps to add some salt.
  10. Nov 19, 2009 #9


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    That's generally a myth. Most people drink plenty, and often far more than they need to drink to remain hydrated. Unless you're ill, or working out for a long time in the heat, as long as you drink when you're thirsty, you'll be fine.

    Here's a simple test if you're concerned you may be dehydrated. Pinch the skin on the back of your hand into a little tent. If it immediately returns to normal when you let it go, you're hydrated. If it stays tented when you let it go, or returns to normal slowly, you're dehydrated.
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