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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

#651

Post by wildmanx »

mardifoufs wrote: post #631
wildmanx wrote: post #572

Irony. A linked article describing a scientist trying to rigorously find out how weight changes and energy expenditure and diet are connected, revealing the little we do know and the vast sea of what we do not know. The discussion here: full of anecdotes and bro science berating one another "that's not how it works, it works like this", "I personally do this-and-that", "you just have to x-y-z, it's that simple".

Yes, but this is one study out of thousands. It's not because it's a paper by PhDs that you just have to take all their results as the new truth and ignore the rest of the literature. It's way way more "bro science"-like to just look at the latest controversial study/paper/research's results while ignoring everything else. Consensus is important and even more so with such a controversial result. Also, how is it bad f…

This article is not a scientific paper. It's describing some effects that are observed in a lab.

The world is not so binary as you make it out to be. The article is not forming a "new truth". Of course elite athletes are eating a lot. Nobody was questioning that. Neither do anecdotes stating "I trained my butt off, it worked" negate what's in the article.

The topic is complex, too complex to be pressed into a simple slogan. The article is not "controversial" to anybody remotely knowledgeable about biology.

You can question that the world is complex, but that won't make it less complex.

Re: Scientist busts myths about how humans burn calories

#652

Post by wbsss4412 »

rob74 wrote: post #349
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…

Congratulations! I would be happy to lose "only" 10 kg (hell, 5 kg would be good for a start), but since Covid and home office my weight has been (slowly, but steadily) going in the wrong direction. Yeah, you can and do burn calories by exercising, but it's depressing how little it is. And it's also depressing if I look at the graph that some 40 to 50 year olds seem to still have the metabolism of a toddler - I'm def…

An important thing to keep in mind is that a substantial amount of calories can be burned outside of formal exercise. Incorporating more walking into your day, general activities that involve movement rather than sitting at a desk, etc

Re: Scientist busts myths about how humans burn calories

#653

Post by wildmanx »

tom-thistime wrote: post #648
wildmanx wrote: post #645

Earlier quoted context omitted.

It's a popular science article. What did you expect? If you want all the details, read the actual published studies. For the general public, scientists need to simplify things.

I'd expect them not to call ordinary long-accepted facts "myths" without some kind of coherent explanation. That isn't simplification.

Which "facts" does the article call "myths"? The word "myth" exists twice in it, one of which is in the heading.

That's just part of phrasing everything in catchy popular science terms. Apparently, if you don't do that, then nobody is going to read your article as it reads too boring. (I also find that sad.)

The "train yourself out of obesity" idea that one of the interviewed scientists calls "zombie idea" is not an "ordinary long-accepted fact". Maybe in bro science circles, where obese people are generally just regarded as lazy who just don't get their act together, but that's now how actual medical experts think about this.

The article is another piece in the puzzle of trying to understand how things work. It's not a "myth buster".

Re: Scientist busts myths about how humans burn calories

#654

Post by everforward »

mmmpop wrote: post #626
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…

I get the impression that cardio affects some people differently. I'm taking some time off from my 30+ miles a week running habit to let my foot heal up. I'm now at about 10 miles + cycling and nordic skiing when I can but overall probably 1/2 to 2/3 the cardio than I've been used to for the past 4 or 5 years. But I've had no problem keeping weight off by just adjusting the amount that I eat. However, if I upped the…

Those "calories burned" calculators are also not very good, so you may just be in the margin of error.

It's easy to calculate how much energy it takes to propel a given weight 5 miles. It's hard to tell how many calories a person burns to produce that energy. Your ratios of aerobic to anaerobic respiration are going to impact that wildly, which will depend on how much oxygen your body can absorb and how quickly you're burning through oxygen. There's a huge gap in the amount of energy cells get from each. Aerobic respiration produces up to 38 ATP per glucose, while anaerobic produces only 2 ATP per glucose.

Running form probably plays into that as well, if you've got some kind of suboptimal gait or you're swinging your arms a lot or something like that.

Re: Scientist busts myths about how humans burn calories

#655

Post by gilbetron »

stkdump wrote: post #277
urthor wrote: post #114

The thing is, exercise still reduces appetite. It raises the blood sugar levels as the body supplies the muscles with carbohydrates, and triggers a complementary response in appetite hormones. Finally, and most importantly: Exercise releases dopamine. Dieting is universally a mood killer, because kilo-joule deficit equals starvation. So whilst it does not directly impact weight loss. It still makes it (a bit) easier.…

For long years I didn't really try to loose weight, because I thought it would require me to work out, which I didn't want to do. I know enough people with joint problems very likely relating to the amount of work out they did/do, even though they never were overweight. Two years back I decided to go against convential wisdom and attempt weight loss without any work out at all. With tremendous success. I understand t…

It's so weird that you feel pressure to feel bad about how you went about it :( I apologize that society is so messed up. Caloric reduction without exercise is totally a valid way to lose weight! There are plenty of people that do it - you get tired when you diet, and so "hibernating" can help. It works for you and that's all that matters.

I know, for instance, Penn Teller lost his weight in the same way - he decided to just eat baked/boiled potatoes with nothing else and just chilled out for a 100 days and lost 100 lbs. That's what worked for him!

https://www.goodhousekeeping.com/health/diet-nutrition/news/...

Re: Scientist busts myths about how humans burn calories

#656

Post by throwawayboise »

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…

> there must be a point at which exercise _does_ increase energy expenditure

Of course there is. The problem is that it's much easier to eat than it is to exercise. You can eat a Big Mac in 5 minutes, and you'd have to run or bike for hours to burn those calories off. A 30 minute jog on a treadmill won't do it.

Most people eat more calories than they need, and would have to exercise much more than they realize to burn them off. So losing weight over a reasonably short period of time almost always requires cutting calories. Few people have enough free time to do it with exercise alone.

Re: Scientist busts myths about how humans burn calories

#657

Post by soperj »

vl wrote: post #262
soperj wrote: post #254

Earlier quoted context omitted.

It's not true though. If you exercise enough you will be in a calorie deficit regardless of what you eat. I knew rowers that couldn't keep weight on during the season no matter what they ate, and they ate a lot. The exercise is what is causing the calorie deficit, not watching what they ate.

It is an exception though. Very few people exercise to this level. Similarly you can eat as much as you can if you nicking across Antarctic, but this is not exactly a typical activity.

It still makes the premise that you can't defeat a bad diet bullshit.

Re: Scientist busts myths about how humans burn calories

#658

Post by soperj »

lordnacho wrote: post #261
soperj wrote: post #254

Earlier quoted context omitted.

It's not true though. If you exercise enough you will be in a calorie deficit regardless of what you eat. I knew rowers that couldn't keep weight on during the season no matter what they ate, and they ate a lot. The exercise is what is causing the calorie deficit, not watching what they ate.

But you can eat the calories you spend in just a few minutes. If you have a pile of Mars bars, that will supply enough energy to compensate an hour on the treadmill. Might not be the typical thing an athlete eats, but it certainly keeps the weight on a lot of people.

My buddy on the rowing team would regularly eat 12 eggs + bacon + sausage & toast for breakfast after rowing. They were eating to excess to try to keep on weight and couldn't actually do it.

Re: Scientist busts myths about how humans burn calories

#659

Post by JeremyNT »

NoboruWataya wrote: post #616
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…

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 role in weight management. There's truth in the "you can't outrun your fork" meme, and it's good to remind people of the greater importance of diet for weight management to counter the widespread myths about exercise being some cure-all here. However, I do worry that overly reductive takes risk swinging the pendulum too far in the opposite direction.

Re: Scientist busts myths about how humans burn calories

#660

Post by artdigital »

Tenoke wrote: post #599
AnIdiotOnTheNet wrote: post #570

Earlier quoted context omitted.

> Write down what you eat for a while and its calories. Weigh yourself daily as well and write that down too. If after a week your weight went up: Your calories are above your TDEE. If it went down: Your calories are under your TDEE. Not necessarily. It is important to remember that water weighs ~1lb/pt and there are a lot of things that affect how much water your body is carrying at any given moment. Depending on yo…

That's why they are telling you (as is common) to compare the results on a weekly basis which reduces the variance. TDEE calculations from scratch are much much more unreliable than empirically finding out and mostly good for a starting point.

Yes, that’s why I suggested weekly

You can of course calculate the TDEE of your target weight but like you implied, unless you know your own, based on your own metabolism and intake, the data is never going to be accurate

For example I eat much less than my bodybuilder friends. When I went with the calories that they recommended to me I gained so much fat with a very active workout schedule and noone had a explanation why. Maybe it’s hormones, maybe medicine I take, maybe something else. I now eat much less than you’d expect from a person with my height and age, but I still gain weight, because my actual calculated TDEE is comparatively low

Having that data on hand as a reference is incredibly helpful to plan my weight progress

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