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Scientist busts myths about how humans burn calories

science.org

531–540 of 753 posts

Re: Scientist busts myths about how humans burn calories

#532

Last thing I saw was "The son of two high school English teachers, Pontzer grew up on 40 hectares of woods in the Appalachian bla bla bla..." You know that sentence. So many articles have that sentence. The one where it veers off course to talk about the (usually uninteresting) person who found the thing the article is ostensibly and nominally about. Am I alone in being perfectly happy reading about science for the d…

Indeed I find a lot of NYtimes articles are filled with fluff like this and I find myself skipping to the core info.

Re: Scientist busts myths about how humans burn calories

#533
post #4

> “You can’t exercise your way out of obesity,” […] “you can’t outrun a bad diet.” While this article is being a bit dramatic and possibly understating the impact of exercise slightly, I feel a little dumb that I didn’t know this earlier. It took me several decades too long to understand the obvious, that exercise is for building strength, and losing weight happens by eating less. I tried for way too many years to ex…

Everybody is 100% responsible for what they eat. There is no excuse.

Re: Scientist busts myths about how humans burn calories

#534
post #406

Earlier quoted context omitted.

Yeah, I thought this. There's clearly an amount of exercise that will cause you to lose weight. An interesting question is whether your body prevents you from achieving that. Cycling was always interesting to me in this context because it seems easier to burn energy on a bike than other forms of exercise.

When cycling there's this "wall" you hit after a few hours. At least I do. After that it's much harder to keep pace or go uphill.

Indeed, but you can keep going just about. I've properly hit the wall once, and that was an unpleasant experience - nearly fainting and seriously in danger of falling off my bike, but I think that was largely a hard removal of all accessible glycogen, and it was years ago when I was relatively green. Now I just tend to eventually find it hard and unpleasant.

Re: Scientist busts myths about how humans burn calories

#535

Earlier quoted context omitted.

I don't get it, how is that a myth or controversial. Cutting empty calories is the easiest to remove calories from daily total. Exercise further decreases the ratio of calories in calories out. Bottom line is: calories in - calories out. There are caveats there for sure, like increasing muscle mass increases idle caloric burn. Different types of food have different effect promoting or impeding metabolism.

calories in - calories out was debunked a while ago. Different types of food and diet cause different degrees of weight gain or loss. For an extreme example compare 100 calories of glucose to 100 calories of fibre, both are types of sugar. The fibre contains an extra electron that acts like a shell, and the body has to expend energy breaking that bond to make it digestible. So most fibre passes through you without af…

> calories in - calories out was debunked a while ago.

No, it wasn't. It's the generally accepted model of human weight gain. It's what most scientists who study this topic believe to be true. (And really, it's the only model that makes any sense, and is incredibly easy to test)

They only people who disagree with this model are considered to be outside the mainstream of science. They might be right (I don't think so though) - but it's certainly not debunked.

Re: Scientist busts myths about how humans burn calories

#536

Earlier quoted context omitted.

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 befo…

> 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.…

Cycling is only approximately 25% mechanically efficient, so the parent is correct. There's a lot of heat to get rid of.

Re: Scientist busts myths about how humans burn calories

#537

Last thing I saw was "The son of two high school English teachers, Pontzer grew up on 40 hectares of woods in the Appalachian bla bla bla..." You know that sentence. So many articles have that sentence. The one where it veers off course to talk about the (usually uninteresting) person who found the thing the article is ostensibly and nominally about. Am I alone in being perfectly happy reading about science for the d…

Could machine learning could help with this? Could some algorithm be created to strip the padding from such articles just leaving the useful stuff?

I would expect machine learning to be more useful in generating this kind of fluff.

Re: Scientist busts myths about how humans burn calories

#538
post #450

Earlier quoted context omitted.

Isn't it anaerobic exercise, though, and from what I remember to lose weight you want aerobic exercise?

Thats correct. Yes it burns much fuel but also the wrong one

I'm confused. I'm being downvoted but you're saying I'm right?

Re: Scientist busts myths about how humans burn calories

#539
post #384

Earlier quoted context omitted.

> If I start lifting 20lbs and 3 years later I still lift that of course I won't lose weight. This example is kind of bad :-) You don't lose weight by lifting weights, in general. And amusingly, if you did want to lose weight by lifting weights, your example is precisely how you > lose weight. You lift 10kgs over and over and over again, or even better, incorporate the extra weight into some sort of cardio routine. I…

This is not accurate, weightlifting with a reasonably difficult weight for your strength level is one of the most effective ways to burn calories.

I used to think this too, it's a popular talking point in favor of strength training.

But as far as I know it's wrong.

A one hour session of strength training will involve some amount of work, and a lot of rest. Compared to doing cardio, where an hour of work is an entire hour of elevated energy expenditure, you're effectively burning a lot less during strength training.

In addition, the "after burn" effect is very minor (in the extra tens of calories only range).

Re: Scientist busts myths about how humans burn calories

#540
post #483

"You can't burn calories. Calories is a measure of heat. You can't burn heat." - Bart Kay CICO, Calories in/Calories out also doesn't work like that in the human body, because the human body is not a closed system. https://www.youtube.com/watch?v=crA0MLKleBQ

In that case, explain to me how my house gets warm from burning caloric gas

... calories are obviously the measure of how much heat you get from burning something, not the heat itself that you're "burning"

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