5 ms·

The standout quote for me: "[immune cells] moved elsewhere, migrating to the animals’ guts or lungs, portions of the body that might be expected to need extra i

The standout quote for me: "[immune cells] moved elsewhere, migrating to the animals’ guts or lungs, portions of the body that might be expected to need extra immune help after hard exercise". Rapidly producing immune cells during exercise, then letting them (and more) die off would be a baffling response. But pumping them into the lungs (because you've been breathing hard through your mouth) and gut (for when you make up lost energy, and maybe eat some raw meat you've been hunting)? That makes a great deal of sense. That effect is unconfirmed in humans, but it would ground our observations in an evolutionarily-sane outcome.

Retric 9y ago
Exercise pushes stuff around in your gut which is probably more directly related to the immune response than the possibility of eating raw meat.
- boris 9y ago
  Why would you go run (hunt) if there is still stuff (food) in your gut.
  - DamnYuppie 9y ago
    Best to hunt when you are loaded up on fuel. Don't want to be hunting when energy is low as you will most likely be less successful as your focus, patience, and response times will all be lower. Hunting isn't like going to the store, success isn't guaranteed.
    - bluGill 9y ago
      That is why you hunt when you are "out of fuel": you can try to hunt just after you eat, but when you fail you get to try again while "out of fuel". (Out of fuel in quotes - presumably the body has enough energy stores for a few more hunts even when it didn't find anything to eat the day before.)
      - DamnYuppie 9y ago
        My comment was definitely taken out of context, I didn't mean to eat and run out the door. The intent was you need to be well fueled and not depleted.
    - donovanh 9y ago
      I think the opposite. People that fast for a period (> 16 hours) report improved energy levels. This may be because after a while the body enters a ketogenic state where it burns body fat, which is a great source of energy and perfect for when on the hunt.
      - Retric 9y ago
        Depending on food type it can easily take over 2 days to digest food. https://www.mayoclinic.org/digestive-system/expert-answers/faq-20058340 https://www.mayoclinic.org/digestive-system/expert-answers/f...
      - naasking 9y ago
        > I think the opposite. People that fast for a period (> 16 hours) report improved energy levels. This may be because after a while the body enters a ketogenic state where it burns body fat, which is a great source of energy and perfect for when on the hunt. Ketogenesis requires over a week of carb restriction IIRC. I think fasting yields energy because the body increases various stress hormones to push you to find food so you don't starve.
        dorfsmay 9y ago
        No, it has to do with insulin levels. Google "Jason Fung insulin".
    - dorfsmay 9y ago
      Have you ever tried fasting? One of the biggest issue while fasting is too much energy and difficulty to fall asleep. Have you ever tried to focus on a hard problem at work after a big lunch?
  - Retric 9y ago
    It generally takes 40+ hours from the time you eat to the time you poo. So, humans always have stuff in their gut. https://www.mayoclinic.org/digestive-system/expert-answers/faq-20058340 https://www.mayoclinic.org/digestive-system/expert-answers/f...
  - naasking 9y ago
    Are fed hunters statistically more likely to successfully hunt than unfed hunters? It seems plausible, so hunters that took advantage of their fed state would have had an adaptive advantage.
    - DrScump 9y ago
      As far as we know, humans' originally competitive advantage in hunting was long-distance running. Game could out-sprint humans but not out-distance human hunters. So, after successfully running down game, they must have had enough in the tank to complete the kill. This practice is still evident in some African tribes.
      - naasking 9y ago
        I've heard of persistence hunting, but I've never seen it suggested that was our primary competitive hunting advantage. Do you have a citation of some sort?
she11c0de 9y ago
Also: "Statistically, their [marathon runners] odds of becoming sick were about the same as for anyone else in the race’s host city."
- Bartweiss 9y ago
  Yep - wasn't mentioned in the article, but I'd imagine the reason post-race marathoners are more likely to mistake coughs for colds is that marathons are also demanding. If your muscles ache and you're lethargic and coughing, that looks a lot like a cold.

Retric 9y ago

Exercise pushes stuff around in your gut which is probably more directly related to the immune response than the possibility of eating raw meat.

boris 9y ago
Why would you go run (hunt) if there is still stuff (food) in your gut.
- DamnYuppie 9y ago
  Best to hunt when you are loaded up on fuel. Don't want to be hunting when energy is low as you will most likely be less successful as your focus, patience, and response times will all be lower. Hunting isn't like going to the store, success isn't guaranteed.
  - bluGill 9y ago
    That is why you hunt when you are "out of fuel": you can try to hunt just after you eat, but when you fail you get to try again while "out of fuel". (Out of fuel in quotes - presumably the body has enough energy stores for a few more hunts even when it didn't find anything to eat the day before.)
    - DamnYuppie 9y ago
      My comment was definitely taken out of context, I didn't mean to eat and run out the door. The intent was you need to be well fueled and not depleted.
  - donovanh 9y ago
    I think the opposite. People that fast for a period (> 16 hours) report improved energy levels. This may be because after a while the body enters a ketogenic state where it burns body fat, which is a great source of energy and perfect for when on the hunt.
    - Retric 9y ago
      Depending on food type it can easily take over 2 days to digest food. https://www.mayoclinic.org/digestive-system/expert-answers/faq-20058340 https://www.mayoclinic.org/digestive-system/expert-answers/f...
    - naasking 9y ago
      > I think the opposite. People that fast for a period (> 16 hours) report improved energy levels. This may be because after a while the body enters a ketogenic state where it burns body fat, which is a great source of energy and perfect for when on the hunt. Ketogenesis requires over a week of carb restriction IIRC. I think fasting yields energy because the body increases various stress hormones to push you to find food so you don't starve.
      - dorfsmay 9y ago
        No, it has to do with insulin levels. Google "Jason Fung insulin".
  - dorfsmay 9y ago
    Have you ever tried fasting? One of the biggest issue while fasting is too much energy and difficulty to fall asleep. Have you ever tried to focus on a hard problem at work after a big lunch?
- Retric 9y ago
  It generally takes 40+ hours from the time you eat to the time you poo. So, humans always have stuff in their gut. https://www.mayoclinic.org/digestive-system/expert-answers/faq-20058340 https://www.mayoclinic.org/digestive-system/expert-answers/f...
- naasking 9y ago
  Are fed hunters statistically more likely to successfully hunt than unfed hunters? It seems plausible, so hunters that took advantage of their fed state would have had an adaptive advantage.
  - DrScump 9y ago
    As far as we know, humans' originally competitive advantage in hunting was long-distance running. Game could out-sprint humans but not out-distance human hunters. So, after successfully running down game, they must have had enough in the tank to complete the kill. This practice is still evident in some African tribes.
    - naasking 9y ago
      I've heard of persistence hunting, but I've never seen it suggested that was our primary competitive hunting advantage. Do you have a citation of some sort?

she11c0de 9y ago

Also: "Statistically, their [marathon runners] odds of becoming sick were about the same as for anyone else in the race’s host city."

Bartweiss 9y ago
Yep - wasn't mentioned in the article, but I'd imagine the reason post-race marathoners are more likely to mistake coughs for colds is that marathons are also demanding. If your muscles ache and you're lethargic and coughing, that looks a lot like a cold.