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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

#701

Post by rootusrootus »

What always gets lost in discussion about weight control, IMO, is that it is a mental game. The biological aspects are pretty easy. CICO works. Diets are a strategy for achieving CICO. And ultimately whether you can stick to it is largely a mental thing.

So if you want to lose weight, figure out first why you have a problem to begin with. Because if you don't, then you will lose for a while purely through motivation, and then gain it back when your focus changes to something else.

Of course, there are physiological inputs to the state of mind, as well, which may very well be uncontrollable and largely genetic, so even if you achieve your personal ideal it may not be the body you dream of.

Re: Scientist busts myths about how humans burn calories

#702

Post by Angostura »

JeremyNT wrote: post #659
NoboruWataya wrote: post #616

Earlier quoted context omitted.

It's definitely true that eating less/healthier is the most important part of weight loss. However, perhaps because exercise played a big role in my own weight loss journey, I do feel like people go too far in dismissing it as a weight loss aid. First of all, while a 3k run isn't going to do much to burn off that slice of cake you had with lunch, if you transition from a generally inactive lifestyle to a generally ac…

My own anecdote: I've been a cyclist and/or a runner pretty consistently for the last 20 years. This year I moved to a place where cycling wasn't an option (without driving a long way), and at the same time I injured my knee by overtraining on hills. So I was benched from my typical cardio. The results are unsurprising... I gained 15 pounds over the next 6 months, and am now overweight. Exercise obviously plays a rol…

My own anecdote - when I started cycling about 6 miles to work each, I was ravenous by lunchtime and had much larger lunches than previously - put on a lot of weight.

Re: Scientist busts myths about how humans burn calories

#703

Post by makeitdouble »

dahart wrote: post #670
makeitdouble wrote: post #292

Earlier quoted context omitted.

> truckloads of data on calories and metabolism We have, but most of it seriously flawed because of many issues. For instance this pretty serious study on diets ( http://www.dishlab.org/pubs/MannTomiyamaAmPsy2007.pdf ) had to rely on BMI for segmenting the subjects because the whole field had standardized on BMI. Yet we know for decades that BMI based segmentation is meaningless, BMI itself being a clunky relic of th…

Those statements are technically true, but I’m not exactly sure what you’re trying to say. There’s nothing flawed about observational data that ignores the inner workings of the system, that’s how all of science works. Like you say, it’s physical observations. There’s nothing flawed about measuring wattage output of exercise while keeping food intake constant and noting that most humans lose weight under such conditi…

Science work by repeating experiments: I give you a protocol, you repeat it controlling for the same conditions, and validate my results.

As you say ignoring the inner workings would be fine if we had consistent, culture independent widely reproduced results. Thing is, we don’t.

For anything beyond a clinical trials on specific subjects that stay there for days/weeks to be fully studied, we might not even have valid control groups.

This is why I see comments on us having a vast body of studies to look to be more or less a “look a my library, there’s a lot of books” kind of statement that doesn’t really point at us having actual vast knowledge about the subject.

> It works as a tool for weight loss.

Does it ? to get back to the above point, do you see any consistently reproduced studies on large cohorts of people pointing at it working in the long term?

Re: Scientist busts myths about how humans burn calories

#704

Post by jimmygrapes »

goda90 wrote: post #622
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…

Don't forget Phelps also spends most of his exercise time in water. The body expends energy to maintain thermal equilibrium, and water absorbs heat much more quickly than the air. With several hours of swimming each day, that energy will add up.

Very relevant point. They sure as hell don't make the "Olympic tier" pools at my gym anywhere near body temperature; I probably spent the first few minutes psyching myself up for the shock then another few minutes getting used to the temperature and recovering from that shock. I don't know for sure but based on my understanding, based on the size of the pool my body would expend energy at a tremendous rate even if I just grabbed the ladder rail and stayed still.

Re: Scientist busts myths about how humans burn calories

#706

Post by AngryData »

isitmadeofglass wrote: post #356
_9omd wrote: post #65

Earlier quoted context omitted.

I think a big part of the issue is that popular fitness and weight loss advice has perpetuated the wrong way to exercise to loose weight. When most people think about exercise for weight loss, they imagine long exhausting sessions on the treadmill, dripping with sweat, and a high calorie burn number. While the short term results may seem great based on the immediate calories burned, it's actually a terrible strategy…

> You'll build muscle which will increase the resting metabolism This is another myth. Even if you put on a serious amount of muscle, the change to your daily calorie burn is insignificantly increased in the larger scale of things. Don’t to strength training to lose weight, so Strength training to get strong.

I don't know if I can accept that offhand because high levels of muscle atrophy is a human adapted trait specifically to save calories for the brain. If muscle maintenance costs were so insignificant why would we have adapted a trait to make us physically weaker?

This is anecdotal but the difference between what I can eat working on a farm with having lots of muscle mass and sitting around on a computer with that same muscle mass was not really significant. But the difference between sitting at a desk with a lot of muscle mass and sitting at a desk with noticeably less muscle mass is night and day in how much I have to eat. With small and inconsistent amounts of strength exercise to maintain a bit more muscle mass again, my caloric expenditure went back up, far beyond what is lost from the exercise itself.

Re: Scientist busts myths about how humans burn calories

#707

Post by dahart »

makeitdouble wrote: post #703
dahart wrote: post #670

Earlier quoted context omitted.

Those statements are technically true, but I’m not exactly sure what you’re trying to say. There’s nothing flawed about observational data that ignores the inner workings of the system, that’s how all of science works. Like you say, it’s physical observations. There’s nothing flawed about measuring wattage output of exercise while keeping food intake constant and noting that most humans lose weight under such conditi…

Science work by repeating experiments: I give you a protocol, you repeat it controlling for the same conditions, and validate my results. As you say ignoring the inner workings would be fine if we had consistent, culture independent widely reproduced results. Thing is, we don’t. For anything beyond a clinical trials on specific subjects that stay there for days/weeks to be fully studied, we might not even have valid…

Still not sure what you’re trying to say. Are you skeptical that reducing caloric intake works? Or skeptical that counting calories helps to reduce caloric intake? Are you skeptical about whether calories are a metric? What exactly do you think doesn’t work, and why? Why are you claiming that we don’t have culturally independent results? I don’t believe that’s true.

If you’re asking whether calorie counting has been studied and controlled enough to know if it works as a weight loss tool in practice, the answer is yes. You don’t need a study for this part; it’s physics. If you are maintaining weight and then stop eating you will die. If you are maintaining weight and then cut your diet in half you will lose weight. I posted a link to one survey on this somewhere in this thread that should be easy to find that demonstrates the rate of metabolic adaptation to caloric restriction (it’s about 15%). But you can Google this and find out for yourself, there are many many papers in many many languages, and you looking for your own sources will be better than being skeptical of anything I suggest. The health agencies of every developed country in the world publish caloric recommendations and have resources and research information available.

Literally millions and millions of people globally have successfully used CICO to manage weight, and the primary complaint is not that it doesn’t work, the primary complaint is that it’s difficult to implement and make habitual, it requires too much work and/or control. When most people say “it doesn’t work”, what they mean is “it doesn’t work for me because I couldn’t establish a working routine, the habit doesn’t stick easily.” There are no studies showing normal people reducing their caloric intake significantly and failing to lose weight.

Re: Scientist busts myths about how humans burn calories

#708

Post by zargon »

dahart wrote: post #670
makeitdouble wrote: post #292

Earlier quoted context omitted.

> truckloads of data on calories and metabolism We have, but most of it seriously flawed because of many issues. For instance this pretty serious study on diets ( http://www.dishlab.org/pubs/MannTomiyamaAmPsy2007.pdf ) had to rely on BMI for segmenting the subjects because the whole field had standardized on BMI. Yet we know for decades that BMI based segmentation is meaningless, BMI itself being a clunky relic of th…

Those statements are technically true, but I’m not exactly sure what you’re trying to say. There’s nothing flawed about observational data that ignores the inner workings of the system, that’s how all of science works. Like you say, it’s physical observations. There’s nothing flawed about measuring wattage output of exercise while keeping food intake constant and noting that most humans lose weight under such conditi…

> If I want to control mass, therefore, tracking and controlling my input and output is more or less guaranteed to work.

It's wonderful that your physiology is aligned with your goal of doing this. But in this control pathway there are billions of neurons, trillions of bacteria, I don't know how many biochemical signals, all feeding back into each other. Reducing all of this to "controlling input" is one of the most harmful ideas in public health. For people who struggle with weight it is just setting them up to fail and blame themselves for it. Repeated over, and over, and over.

Re: Scientist busts myths about how humans burn calories

#709

Post by nradov »

throwaway09223 wrote: post #690
nradov wrote: post #681

Earlier quoted context omitted.

It's doubtful that your measurements are even close to accurate. If you're on a stationary bike then the distance displayed is completely meaningless. The equipment manufacturers just show those numbers to make their customers feel good. In terms of calories they are in no way comparable to real outdoor cycling. You can get a great workout on a stationary bike but you need to be realistic about the true power output.…

"Completely meaningless" and "in no way comparable?" These statements are rather extreme and seem impossible to support. Energy output per mile with real world cycling has enormous variance as well. Why so much concern for precision regarding one and not the other? I don't think there's much point in continuing here.

I'll continue with one last comment just for the sake of others who might be reading. The "distance" displayed on most stationary bikes is calculated by counting flywheel revolutions and multiplying by some arbitrary factor. It has no real correlation with the actual distance you would cover by pedaling a real bike with the same effort. It's a totally pointless number that tells you nothing useful about caloric expenditure, but some customers want to see it so the manufacturers put it on the display.

You can get an accurate calculation of real world cycling calories with a power meter. Everyone's cycling efficiency in terms of power output per calorie burned falls within a fairly narrow range so converting from time and watts to calories is simple. A good power meter accurate to within a couple percent can be added to any bike for about $700.

Smart trainers like a Tacx Neo or Wahoo Kickr also have accurate power meters built in. Those are substantially different from typical stationary bikes.

Re: Scientist busts myths about how humans burn calories

#710

Post by makeitdouble »

dahart wrote: post #707
makeitdouble wrote: post #703

Earlier quoted context omitted.

Science work by repeating experiments: I give you a protocol, you repeat it controlling for the same conditions, and validate my results. As you say ignoring the inner workings would be fine if we had consistent, culture independent widely reproduced results. Thing is, we don’t. For anything beyond a clinical trials on specific subjects that stay there for days/weeks to be fully studied, we might not even have valid…

Still not sure what you’re trying to say. Are you skeptical that reducing caloric intake works? Or skeptical that counting calories helps to reduce caloric intake? Are you skeptical about whether calories are a metric? What exactly do you think doesn’t work, and why? Why are you claiming that we don’t have culturally independent results? I don’t believe that’s true. If you’re asking whether calorie counting has been…

> If you’re asking whether calorie counting has been studied and controlled enough to know if it works as a weight loss tool in practice, the answer is yes. You don’t need a study for this part

This is the shortcut I am pointing at.

You're bringing in a pure assumption. I need an actual, well designed study that shows that your inntuition is in fact correct (to reiterate we're talking weight loss, and in particular stable loss, not some blimp in a three weeks trial)

Can you point to a rock solid study on it? There are countless studies on the most obvious things. Take any of what you call "physics" and you'll have large studies from reputable research labs analysing the long term impact on stricly controlled groups. CICO is not some hippy unknown strategy, the press turns around "obesity crisis" headlines year long, there is no shortage of funding for research."It's obvious so nobody tested it" isn't a valid argument.

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