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Scientist busts myths about how humans burn calories

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Re: Scientist busts myths about how humans burn calories

#391

Post by TulliusCicero »

elvis10ten wrote: post #224
dahart wrote: 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…

I think we have fitness wrong in this side of the world. I grew up seeing 60 year olds that were as fit as youths in the west. They didn’t have a treadmill or did keto diets. My take away was fitness should be a lifestyle and to avoid lots of western food (sugar, processed, empty calories, I drink only water, etc). I don’t count calories and can eat twice in the morning. If I counted, both morning meals are less than…

> My take away was fitness should be a lifestyle

There's only one way this actually happens for a majority of the population: exercise being built into daily habits, in a way that's so natural that it almost seems unavoidable.

The Netherlands seems to have the right of it: their urban design strongly supports walking and biking, and indeed, their rates of 'active transportation' are very high.

As a bonus, walk and bike infrastructure is quite cheap to build and maintain compared to car infrastructure.

Re: Scientist busts myths about how humans burn calories

#392

Post by hgomersall »

Elte wrote: post #321
y4mi wrote: post #266

Earlier quoted context omitted.

And yet the article you're commenting on says that you don't burn more calories by exercising... If it is true, it definitely changes the narrative.

I'm a bit confused by this point in the article, because it also states: > There seems to be a hard limit on how many calories our bodies can burn per day, set by how fast we can digest food and turn it into energy. He calculates that the ceiling for an 85-kilogram man would be about 4650 calories per day. Given that "regular" people clearly do not burn 4650 calories per day, and it is possible to burn 4650 calories…

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.

Re: Scientist busts myths about how humans burn calories

#393

Post by [deleted] »

michalu wrote: post #352
rdiddly wrote: post #312

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…

Whenever there's insignificant science making "controversial" claims like "you can't lose weight with sport" journalist will provide storytelling instead of science. The whole premise of that "You can’t exercise your way out of obesity" is that you burn more calories when you start running than later on as you continue. What's so controversial about it? It's normal that body optimizes for energy expenditure that's wh…

[deleted]

Re: Scientist busts myths about how humans burn calories

#394

Post by tpoacher »

rdiddly wrote: post #312

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…

I had a very similar outburst recently :p

https://news.ycombinator.com/item?id=30344510

Re: Scientist busts myths about how humans burn calories

#395

Post by FrankyHollywood »

michalu wrote: post #352
rdiddly wrote: post #312

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…

Whenever there's insignificant science making "controversial" claims like "you can't lose weight with sport" journalist will provide storytelling instead of science. The whole premise of that "You can’t exercise your way out of obesity" is that you burn more calories when you start running than later on as you continue. What's so controversial about it? It's normal that body optimizes for energy expenditure that's wh…

> If I start lifting 20lbs and 3 years later I still lift that of course I won't lose weight.

I don't understand, your body optimizes, and uses 20% less energy. However, you are still using the 80% which is more than not doing anything at all don't you?

Re: Scientist busts myths about how humans burn calories

#396

Post by ajuc »

hnbad wrote: post #389
verytrivial wrote: post #369

Earlier quoted context omitted.

In the context of nutrition the word calories always means dietary calories, so the kilo- prefix is redundant unless discussing physics, or commenting on HN...Ooooh, ok.

The practice of indicating kcals as "Calories" always seemed to be an American thing to me. I don't know how widespread this is outside the US but there are plenty of countries that use "kcal" in nutritional tables and such. People will still colloquially confuse calories and kilocalories a lot but that's largely due to bad translations (similar to mistranslating short billions).

In Poland you write "100 kcal" but say "100 kalorii" unless it's in scientific context.

Re: Scientist busts myths about how humans burn calories

#397

Post by Broken_Hippo »

pawelmurias wrote: post #366
dahart wrote: 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…

You can totally loose weight by exercising, it's just regular people don't exercise hard enough. If you do pro athlete levels of exercise it will start affecting your weight a lot.

I've never met someone doing pro-athlete levels of exercise that doesn't stick to some sort of regimented diet. Have you? And even if you do meet those folks, chances are they simply don't eat as much as before due to spending more time, well, exercising, and it makes for a caloric deficit, albeit accidental.

And that's the thing: Once you start changing your diet - the stuff you eat or the timing of your food - to do the exercise, you can't really say it is the exercise affecting your weight.

Re: Scientist busts myths about how humans burn calories

#398

Post by tempestn »

aixi wrote: post #375
Elte wrote: post #321

Earlier quoted context omitted.

I'm a bit confused by this point in the article, because it also states: > There seems to be a hard limit on how many calories our bodies can burn per day, set by how fast we can digest food and turn it into energy. He calculates that the ceiling for an 85-kilogram man would be about 4650 calories per day. Given that "regular" people clearly do not burn 4650 calories per day, and it is possible to burn 4650 calories…

out of context, that quote is really funny; what happens once you reach 4650 calories? you start violating the rules of thermodynamics? (i know your body starts compensating for it and burning less calories, but still)

Long term, yes. Short term you might be able to get some from fat stores. But the claim is that ~4650 is the most you can persistently get from food intake per day.

Re: Scientist busts myths about how humans burn calories

#399

Post by csee »

skohan wrote: post #381
csee wrote: post #320

Earlier quoted context omitted.

Well that's what the article says. The Hazda who walk 8-12 km a day burn the less calories as an average American (or the same after adjusting for body weight). Also that Phelps thing is highly questionable. He says he "probably" burns 8-10k, not 12k. Not the type of statement you want to rely on to dismiss all this work.

I just have a hard time believing it to be true that no amount of exercise will increase the overall caloric expenditure. For example, I've done a few multi-week bike tours, and we ate an enormous amount of mostly pasta every day, and managed to peel off a few pounds each by the end of it.

The article mentions a study that tracked energy expenditure of runners over many weeks, and found that the energy expenditure was much lower at the tail end of the experiment, suggesting the body gets accustomed to the activity somehow and burns less energy.

Re: Scientist busts myths about how humans burn calories

#400

Post by tempestn »

Elte wrote: post #321
y4mi wrote: post #266

Earlier quoted context omitted.

And yet the article you're commenting on says that you don't burn more calories by exercising... If it is true, it definitely changes the narrative.

I'm a bit confused by this point in the article, because it also states: > There seems to be a hard limit on how many calories our bodies can burn per day, set by how fast we can digest food and turn it into energy. He calculates that the ceiling for an 85-kilogram man would be about 4650 calories per day. Given that "regular" people clearly do not burn 4650 calories per day, and it is possible to burn 4650 calories…

Yeah, the article isn't very clear on this. ISTM the claim is not that exercise doesn't increase energy consumption at all, but just that it increases it by much less than the amount of energy expended in the exercise, because the body (partially) compensates elsewhere. Whether the degree of compensation varies based on amount of exercise I'm not sure, and I wish it had explained. I expect it probably would, as presumably there would only be so much 'low hanging fruit' for your body to use when compensating.
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