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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

#301

Post by zmmmmm »

geoduck14 wrote: post #70
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…

>A lot of people know this already, so it’s not busting everyone’s myths It is still worth mentioning - because it is so easy to overlook. Some simple math: if I go all out on a row machine for 30 minutes, I'll burn 300 calories. If I eat 2 extra slices of pizza, it is easiely 300 calories If I swap a turkey sandwich with healthy options, I can reduce my linch calories by 300 - and I can save even more during dinner…

But what if I like pizza?

The thing is, the 300 calories from rowing shouldn't be compared to the absolute calorific requirement (say 2500 calories) but the surplus. So Maybe I'm overweight because I need 2500 and I eat 3000. Thats 500 too much, but take out 300 and that's 60% of what I need to at least reach equilibrium. It makes a huge difference to how much I need to sacrifice out of my diet.

Re: Scientist busts myths about how humans burn calories

#302

Post by bsder »

sizzle wrote: post #298
bsder wrote: post #210

Earlier quoted context omitted.

> But then I hit a plateau (a high plateau, not a low one) where I was unable to drop weight no matter how low I cut my calories. Fat cells "remember" their metabolic environment when they were created--ie. they "remember" your weight and fight you when you try to reduce it. It's one of the problems with dieting to large weight losses. It is somewhere around 3 years for a fat cell to die off and be replaced. You prob…

I thought you never lose fat cells, they only shrink? Got a citation for that assertion?

It's been a while. IIRC, it was from an article discussing the fact that radioactive fallout allows critical measurements of cellular lifetimes and that in about 25 years the fallout levels will be too low to do the experiments. I'll see if I can cough it up.

Sorry, medium link: https://prosetech.medium.com/what-nuclear-bombs-tell-us-abou...

> The carbon-14 fat-cell study also revealed that fat cells don’t last forever. Fat or thin, your body replaces roughly 10% of your fat cells every year. If you have more fat cells to begin with, you’ll have more fat cells to replace.

I can't seem to find the study talking about how fat cells remember the chemical environment when they are created.

Re: Scientist busts myths about how humans burn calories

#303

Post by irrational »

deepnotderp wrote: post #282

The conclusion is almost certainly wrong: 1. From a simple sniff test, if this were true, then athletes wouldn't need a lot of calories. This obviously isn't true, eg Phelps eats 8-11K calories a day. I personally eat around 3.5K calories a day. If exercise didn't impact caloric burn I assure you I'd be a lot fatter... 2. The only plausible mechanisms for why exercise wouldn't result in more overall caloric burn is t…

But, surely the researcher is aware of people like Phelps. It wasn’t addressed in this article for the masses, but I wonder if he addresses people like Phelps in his actual research papers.

Re: Scientist busts myths about how humans burn calories

#304

Post by kart23 »

TheSpiceIsLife wrote: post #54

On the matter of food and weight... What of the people who tend toward being thin or lithe? I'm 181cm and 68kg (5'11.26" and 150 pounds) at 40 years old. I can eat and quantity of any food in perpetuity and not gain weight. Although they doesn't mean I don't feel unwell if I were to, say, eat way too much of something. If I lift weights I gain a small amount of muscle mass, but not much. What's the theory(ies) of wha…

I thought I was like this. Track your calories. Eat 3000 calories a day, and a gram of protein per pound of bodyweight (150 grams for you). And I promise you'll gain weight, unless you have something wrong with your digestive system. It's actually pretty hard to eat like that consistently for many skinny people.

Re: Scientist busts myths about how humans burn calories

#305

Post by jordanbeiber »

deepnotderp wrote: post #282

The conclusion is almost certainly wrong: 1. From a simple sniff test, if this were true, then athletes wouldn't need a lot of calories. This obviously isn't true, eg Phelps eats 8-11K calories a day. I personally eat around 3.5K calories a day. If exercise didn't impact caloric burn I assure you I'd be a lot fatter... 2. The only plausible mechanisms for why exercise wouldn't result in more overall caloric burn is t…

About Phelps - he need to build, maintain and condition a whole lot of muscle mass.

He’s incredibly far from a normal human - he’s a true specialist.

Lots more energy goes in to that, compared to losing excess fat and living a “normal” human hunter gatherer existence.

The whole system change once you go google scale, so to speak, and phelps is gmail.

In the words of Ido Portal: we’re human first, movers second and specialists last.

I see relevance in this research in the human/mover perspective.

Re: Scientist busts myths about how humans burn calories

#306

Post by [deleted] »

xurukefi wrote: post #299

"You can’t outrun a bad diet" seems to be the party line among fitness people these days. Anecdotally speaking that's not really true for a lot of people. I run > 100km/week pretty much all year round (most of it on extremely hillly trails) and despite my bad diet consisting mainly of pancakes, white bread, nutella, pizza, fries and burgers, I am not overweight with 78kg at 190cm. Before I picked up running I was mod…

[deleted]

Re: Scientist busts myths about how humans burn calories

#307

Post by ehnto »

octodog wrote: post #136
kevin_thibedeau wrote: post #78

Earlier quoted context omitted.

Running isn't efficient at high speeds. The same with cycling. It's funny to see people buy a bike for exercise and then roll along at a crawl, expending less energy than walking.

It's more exercise than driving a car though, which is why I think people do that.

You're right, cycle commuting falls in a great niche. It's still fast enough to cover decent distances in a reasonable amount of time, you can still carry your grocery shopping, and it's healthier than driving while still achieving most of the same things.

Re: Scientist busts myths about how humans burn calories

#308

Post by __MatrixMan__ »

ewindal wrote: post #281
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.

You’re reading that wrong. Of course you burn more calories through exercise. Michael Phelps couldn’t have eaten 12k cals a day if exercise didn’t burn calories.

Is it certain that we absorb all of the calories we consume? I went on a backpacking trip with my friends recently and despite similar activity levels everybody was surprised when they noticed that I eat twice as much as anybody else in the group.

Maybe I should bring it up with a doctor, but I feel fine, I just also spend more on food than most.

Re: Scientist busts myths about how humans burn calories

#309

Post by 8bitsrule »

I've a question I've never seen addressed. It's likely that some of what you consume is actually utilized ... and that some, if it's not needed, is just 'ignored' (excreted). Oxygen needed? Very little.

Also some people can eat and eat, whatever they want, and not gain a lot of weight. Genetics has to be part of it.

Re: Scientist busts myths about how humans burn calories

#310

Post by noduerme »

deepnotderp wrote: post #282

The conclusion is almost certainly wrong: 1. From a simple sniff test, if this were true, then athletes wouldn't need a lot of calories. This obviously isn't true, eg Phelps eats 8-11K calories a day. I personally eat around 3.5K calories a day. If exercise didn't impact caloric burn I assure you I'd be a lot fatter... 2. The only plausible mechanisms for why exercise wouldn't result in more overall caloric burn is t…

>> somehow the sedentary lifestyle of your average couch potato

What I got out of the article wasn't that sitting still and not thinking can somehow burn calories; just that strenuous mental activities can burn a great deal more energy in humans than in apes. This is believable to me. I'm a person who falls asleep doing math in my head every night. I got a chance, during a year of pandemic lockdown, to experiment with my own body in this way.

I only eat once per day. I don't keep fixed hours; sometimes I'll stay up for 24, sleep for 16; other times I'm regularly 8/16 sleep/wake. I don't have a set bedtime. I try to maintain 16/48 sleep/wake over any given period.

No matter what, I only eat one meal every 24 hours. I've been doing this for about 20 years.

This makes it easy to measure when I get hungry in relationship to my last meal. My body is well trained to expect about a 24 hour delay; I have no appetite and don't think about food until around 22 hours post-dinner.

Under lockdown conditions, I began to notice that I wasn't hungry as expected on days where I hadn't spent >= 6 hours working on strenuous code. If I took a day off and "couch potato'd", I might not eat at all for 48 hours. But if I focused on code for 8+ hours, I would be hungry on time or early.

I started to experiment with this. I figured out that if I took a 1 hour walk, plus 4 hours programming, it made me hungry right around where 6+ hours of code did. A 1 hour walk - to me - seems about equal to 2 hours of writing code in terms of what my body feedback gives me about my calorie burn.

I don't walk very fast, and I code very intensely.

But that's just it - this article is about solving math problems as a way to burn calories. I have a nice new M1 Mac that only ever turns its fans on or gets warm when I'm using all 10 cores. Last night my task falling asleep was to calculate randomly chosen x/128ths as percentages to five decimal places. My daytime task was harder; and now I'm hungry. And I haven't walked anywhere today.

However: Couch potato, this ain't. And the point about the body's reduced expectation of physical output is probably accurate as well.

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