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To Gu or not to Gu (Read 765 times)

LedLincoln


not bad for mile 25

    What recent info are you refering to?

    I have a feeling that that statement is correct if you have a clause at the end of it. 
    For example....

    Recent info makes me doubt that the salts in Gatorade are beneficial if you're running less than "x" (4) hours

     

    I'm not sure that Koolaid or juice would have any added benefit over Gatorade.

     

    Physiologists who are not paid by the sports drink industry found that the concentration of salts in you sweat is a good deal less than the concentration in your bloodstream.  Therefore, as you sweat, the amount of salt in your blood is actually increasing.  Adding more via sports drinks or salt tablets is not going to help.  The sugar may help.

     

    The Science of Sport

     

    There's also a British Medical Journal article on this, but now you have to register with them to get it in full.

    zonykel


      There's a theory that by not using them during training runs, you can train your body to tend to use fat as a fuel source first, since you aren't continually getting carbs to use as a fuel source instead.

       

      The other part of that is you can bring your body closer to glycogen depletion by not using GUs, which should help you deal with the last miles of a long race (marathon or longer) when you'll almost certainly be nearing or reaching a glycogen depleted state.  

      Note that you're burning fat as fuel when your speed is relatively slow. I think it has to do with the oxygen you're taking in and how long it takes to break down fat vs. glycogen (I'd have to read the appropriate chapter of "Lore of Running" again, since I can't remember exactly). Therefore, if you're going relatively fast during a long run and you're burning glycogen vice fat, you're just going to bonk faster.

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