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Water lost during exercise

ansonrinesmith
ansonrinesmith Posts: 741 Member
edited February 25 in Health and Weight Loss
So I saw a story on BBC (Boom goes the Theory or something like that), that showed during strenuous exercise only a few ounces were lost through sweat. I feel like I sweat WAY more than that, and yesterday I weighed before and after a run (30 min) and was 2lbs less. Thinking I needed to re-hydrate that much. Is this normal? Has anyone else done a pre/post comparison?

Replies

  • DeguelloTex
    DeguelloTex Posts: 6,652 Member
    So I saw a story on BBC (Boom goes the Theory or something like that), that showed during strenuous exercise only a few ounces were lost through sweat. I feel like I sweat WAY more than that, and yesterday I weighed before and after a run (30 min) and was 2lbs less. Thinking I needed to re-hydrate that much. Is this normal? Has anyone else done a pre/post comparison?
    There's no way it's just a few ounces for me. My shirt and shorts are noticeably heavier when I am done and that doesn't even take into account what went into the air. The couple of times I've weighed after exercise I was 1.5 - 2.5 pounds lighter. That's during the summer in Texas, but still... I drink so much water/Mio I forget to log it all.
  • ansonrinesmith
    ansonrinesmith Posts: 741 Member
    https://www.youtube.com/watch?v=f1_i7KiTyDk
    So it was more than I remember (900ml) almost 4 cups. So maybe I'm not that abnormal.
  • 4legsRbetterthan2
    4legsRbetterthan2 Posts: 19,588 MFP Moderator
    it can vary from person to person but weight doesnt lie

    "a pints a pound the world around" I know, annoying, but you will remember it, if you lost 2 lbs of water thats 2 pints (4 cups)
    (this is true of water and not other substances, I am not looking for a density arguement here)
  • _Waffle_
    _Waffle_ Posts: 13,049 Member
    I've lost as much as 6 pounds in a single run. It's perfectly normal. Just make sure you get enough hydration after to make it up.
  • Aaron_K123
    Aaron_K123 Posts: 7,122 Member
    You would have lost some weight from your breath, both water vapor on exhales and CO2/O2 exchange. Not sure how much exactly but CO2/O2 is where genuine, lasting non-water-based weight loss comes from.
This discussion has been closed.