this post was submitted on 28 Sep 2025
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I don’t think you can burn calories without oxygen intake directly proportional to the calorie loss, so it’s actually an excellent measure. Is oxygen not what allows us to catalyze the energy in the first place?
You can burn calories without oxygen (anaerobic metabolism), but it mainly occurs during really intense exercise or loss of blood flow. I think it ends up averaging out in the long run, but I'm not really finding answers at my reading level. At mild exertion levels, the o2-calorie relationship is basically 1:1.
The "true" answer would be a whole-room calorimeter,
but thats a much more significant investment of time and resources.
Even with anaerobic metabolism, the process produces lactate and pyruvate as a byproduct that the body needs to clear that out, which generally involves oxygen consumption. So the energy expenditure might spike in that moment without a corresponding spike in oxygen in that moment, but the amount over time should increase to where the overall amount should still correlate with total calori expenditure.
That's kinda what I assumed, but again: don't read good. What's the time scale to make up the difference?