Comment by scotty79
3 years ago
Think about it this way. The rate at which you burn calories is directly proportional to the rate at which you breathe out CO2 because that what happens with carbon you burn.
So if every day you train for an hour so that your breathing is 3 times faster, then you have additional two hours of burning in a day. 23 usual hours plus one worth 3. So you have 26 instead of 24 hours in a day.
It's way easier to put 15% less on your plate every day than to intensly train for an hour each day while keeping portions the same.
You're assuming that breathing rate is proportional to CO2 breathed out, which I doubt. I barely breath any faster while running than while just sitting here, much less than 3x.
It is directly proportional because of how lungs work. The percentage of CO2 in exhaled air is roughly the same regardless of how fast you are breathing (if you don't artificially accelerate your breathing beyond what your body dictates).
Lungs can't put in more CO2 in breathed out air.
If you breath only slightly faster when you are running than when you are sitting that must mean you ran quite a lot and optimized your stride so that you don't burn much more calories running than sitting.
But more likely explanation is that you are not aware how fast exactly you are breathing when sitting and running. Try to measure it. Also take into account that you might be taking shallower breaths when you are sitting.
Just blow up a balloon when you are sitting and when you are running with your normal exhaled breath for few seconds to test it.
Yes but in numbers it is way more. If I bike for an hour I burn 700-1000kcal . Thats not 15 but 50% of the dayli calorie intake… i am no expert btw. My understanding is that the problem is more that after 20 minuts of sport, at a certain heart rate, is starting to burn fat…but not body fat. More free floating fat. And it takes one hour or so to start burning bodymass. So the fuel for one hour sport is what I ate before and not my bodyfat. Another example. I do mountaineering, mostly 1 week walking in the alps for 10h a day. Thats around 4000kcal more burned a day. And there I see instant results with all my friends coming with me . They get thin very fast. Around 500g of body mass a day :)
> If I bike for an hour I burn 700-1000kcal . Thats not 15 but 50% of the dayli calorie intake…
That's estimated and probably impossible.
1000 kcal is 4184000 joules, divided by 3600 it gives you around 1100W
Human at rest burns about 100W. Pro-cyclist can do additional 400W. There's no way you can burn energy at the rate of 1.1kW consistently for an hour unless you literally set yourself on fire.
EDIT:
I was wrong.
Apparently 700kcal burned per hour of cycling is a pretty realistic number. https://www.welovecycling.com/wide/2020/05/14/how-to-convert...
Also resting kcal burn might be around 1800 per day. So 40% increase in of calories burned by hour of cycling per day every day is achievable.
The question is how can you breathe out additional ~10h of CO2 within an hour?
3 times deeper breathes 3 times faster? Because that carbon has to go somewhere.
You are forgetting about the efficiency of the human body. Roughly, only 21% of your power is transferred to the bike. So a professional adding 400W to the bike is actually consuming ~1900W of power. This all matches up with their nutrition [1]. Namely
> They averaged 91 g of carbs every hour across all of the stages.
That's nearly 400 calories worth of sugar simply while riding the bike. In fact, I would say cycling is a clear counterproof of this article. Their equations are literally (calories in)*efficiency = power and they know exactly how much to feed. I don't disagree that 99% of people are better served eating less, but doing cardio for 2 hours a day + diet management will lead to very quick weight loss. "Very quick" here is 2lbs/week but people have some insane expectations.
[1] - https://www.welovecycling.com/wide/2021/07/01/how-much-do-th...
If you are pro-athlete, I think you could, but 1kW is probably about max a human can burn for longer periods. I managed to output 500W for 5 minutes of rowing, but I'm overweight couch potato.
I think you need to account for human inefficiency. I have to burn more than 1 joule to output 1 joule on a bike. The average efficiency of a human on a bike is somewhere around 20 to 25%.
Cycling is only approximately 25% mechanically efficient, so the parent is correct. There's a lot of heat to get rid of.
8 replies →
Also, you don’t absorb everything you eat. Actually, let me be clear: I have no evidence for this. But the fact that my weight is so consistent despite my radically inconsistent eating and exercising suggests to me that my body can regulate digestion. When I’m in a period when I’m overeating, my body just doesn’t absorb so much.
Again, more speculation, but i would imagine that metabolic disorders involve digestive regulation issues, not just lack of exercise and overeating.
You are arguing a different point. They argued that doing exercise burns more calories than sitting idle.
@1_player said: > Your body burns incredibly more energy just "being there" than you burn moving about.
I was objecting to the word "incredibly".