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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

#281

Post by ewindal »

y4mi wrote: post #266
ajuc wrote: post #192

Earlier quoted context omitted.

Yes counting calories is essential, I had very similar experience (walk 10 km on the weekend ~= burn 600 kcal, then buy a 1000 kcal snack on the way back and wonder why I'm not losing weight), but still the exercise makes a big difference. Last year in march I started counting calories, recording my weight and all exercises I did and walking/biking every day. I lost 30 kg, walked 2100 km, biked 1000 km, and the sum o…

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.

Re: Scientist busts myths about how humans burn calories

#282

Post by deepnotderp »

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 that less energy is expended in non exercising states, eg the body is trying to conserve energy and either reduces metabolism or reduces fidgeting, walking, etc. This often happens to people trying extreme calorie loss diets.

The implication of this is that somehow the sedentary lifestyle of your average couch potato is the "normal" lifestyle for a body, and the lifestyle of a hunter gatherer is "overactive", and their bodies are chronically tired and trying to reduce their metabolisms. That... seems quite unlikely.

3. Finally, this blog post dives into some methodological issues: https://darrendahly.github.io/post/2012-08-31-hunter-gathere...

EDIT: Increased metabolism due to muscle mass is not as big an effect as you’d think: https://www.unm.edu/~lkravitz/Article%20folder/metabolismcon...

Re: Scientist busts myths about how humans burn calories

#283

Post by ajuc »

y4mi wrote: post #266
ajuc wrote: post #192

Earlier quoted context omitted.

Yes counting calories is essential, I had very similar experience (walk 10 km on the weekend ~= burn 600 kcal, then buy a 1000 kcal snack on the way back and wonder why I'm not losing weight), but still the exercise makes a big difference. Last year in march I started counting calories, recording my weight and all exercises I did and walking/biking every day. I lost 30 kg, walked 2100 km, biked 1000 km, and the sum o…

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.

The article says you can't keep unhealthy diet and get fit just by exercising. Which is true in my experience as well - I was eating over 3000 kcal a day before I started counting calories, and if I haven't reduced that - no reasonable amount of exercise would have helped.

What's tricky is that in early 20s I was eating about as much and it was fine.

Re: Scientist busts myths about how humans burn calories

#284

Post by masklinn »

throwaway09223 wrote: post #118
geoduck14 wrote: post #70

Earlier quoted context omitted.

>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…

> if I go all out on a row machine for 30 minutes, I'll burn 300 calories. A stationary bike at a steady 20mph pace is about 500 calories in 30 minutes. That's really significant. An hour will erase about a third of a normal person's diet. When I used to do heavy training (long distance running, weight training) I would eat close to 8k calories a day and I was in fantastic shape. Eating more was necessary to survive,…

> A stationary bike at a steady 20mph pace is about 500 calories in 30 minutes. That's really significant. An hour will erase about a third of a normal person's diet.

That assumes a “normal person” will not compensate for the effort with a snack.

A “reward” pint of ice cream will re-add more calories than the hour of cycling. A “standard serving” will nearly match your half hour.

And that’s an hour at 20mph, which really isn’t in any way the norm.

Re: Scientist busts myths about how humans burn calories

#285

Post by dpark »

dpark wrote: post #180
dugite-code wrote: post #175

Earlier quoted context omitted.

I can't find the link but I remember reading an article about weight lifting raising the resting calorie use for quite some time after the exercise. Also as you say you retain more muscle, and that muscle requires calories at rest potentially altering the overall calculation. I still agree with the overall premise that fixing your diet is probably the most important aspect of weight loss though. May main take-away wa…

For sure, excess post-exercise oxygen consumption (EPOC) is a thing. It is real and measurable. But it’s not some crazy effect that offsets the fact that aerobic exercise is about 2x as calorie intensive as weight training during the actual exercise. As I recall the best way to drive up EPOC is to engage in high intensity interval training. HIIT has a much larger effect on EPOC than weight training (again, if I recal…

Lol. “40 extra pounds of lean mutant.”

Too late to fix the typos now.

Re: Scientist busts myths about how humans burn calories

#286

Post by watwut »

dugite-code wrote: post #25

> Exercise doesn’t help you burn more energy on average I have a problem with this hard statement based on the data because: > He realized he had to go back to basics, measuring the calories expended by humans and animals walking and running on treadmills. > He backed this up with a new analysis of data from another team’s study of sedentary women trained to run half marathons I've always heard that humans, due to ou…

> I've always heard that humans, due to our upright posture, are extremely efficient when it comes to walking and running and so if you want to increase you calories usage via exercise you should lift weights as we are much less efficient at this.

Weight lifting builds muscles. It does makes you more hungry. In addition, you can end up heavier then originally, because muscles weight more then fat. I mean, yes, it will be good weight, the weight composed of muscle, there is no rational reason to go out of way to avoid it. But, it is not loosing weight.

Re: Scientist busts myths about how humans burn calories

#287

Post by guerrilla »

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…

> If exercise didn't impact caloric burn I assure you I'd be a lot fatter...

Simply having more muscle mass can burn calories too. Most people don't spend most of their time training either, so comparing to elite athletes is fairly irrelevant.

Re: Scientist busts myths about how humans burn calories

#288

Post by deepnotderp »

guerrilla wrote: post #287
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…

> If exercise didn't impact caloric burn I assure you I'd be a lot fatter... Simply having more muscle mass can burn calories too. Most people don't spend most of their time training either, so comparing to elite athletes is fairly irrelevant.

True, but the effect is not as big as you would think, see eg: https://www.unm.edu/~lkravitz/Article%20folder/metabolismcon...

Re: Scientist busts myths about how humans burn calories

#289

Post by ckastner »

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…

> From a simple sniff test, if this were true, then athletes wouldn't need a lot of calories.

That was my first thought as well.

It's even more evident with certain types of sports. Take cycling for example. Lifting mass up a mountain is going to take quite a bit of energy; maintaining a constant speed in the face of wind resistance will take energy. That energy has to come from somewhere.

Re: Scientist busts myths about how humans burn calories

#290

Post by ehnto »

dugite-code wrote: post #40
learc83 wrote: post #7

How do his results line up real world data like soldiers needing about 5k calories a day when active. Or athletes like Michael Phelps consuming 8k-10k calories a day while training?

From my read of the article the data is heavily biased towards running as the exercise of choice, probably because measuring CO2 is easy and non-intrusive to do on a treadmill. They do mention utilizing doubly labeled water but don't say if they only used that for sedentary participants or measured a wider range of exercises. Given I have always heard/read how efficient humans are at running if they didn't account fo…

I can't line up my real world experience with this article, I have to suspect that he may be right for his specific study parameters but that may not actually be applicable to generalized advice as it's being interpreted here.
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