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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

#681

Post by nradov »

throwaway09223 wrote: post #672
nradov wrote: post #661

Earlier quoted context omitted.

High aerobic fitness evaporates pretty quickly. The training you did a decade ago will not carry over to today. However, there are a few genetic outliers who can quickly build up a high level of fitness with just a short training program. You could be one of them, but it's more likely you're just getting bad data. Absolute heart rate doesn't tell us much about calorie consumption because there's a huge variation betw…

It seems doubtful the measurements would be far off. The numbers fit with the expected 50 or so calories per mile biked.

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.

What is the actual power output in watts? Has it been properly calibrated? If not then you're just fooling yourself.

Re: Scientist busts myths about how humans burn calories

#682

Post by obpe »

JeremyNT wrote: post #677
coryfklein wrote: post #671

Earlier quoted context omitted.

The article seems to indicate that, counterintuitively, your Total Energy Expenditure (TEE) wouldn't have changed much after you stopped the regular cycling (see the section about how hunter gatherers walking 8-14 km a day had the same TEE as average US), so your weight gain may have been from second-order effects of coming back to your diet. Do you remember whether your diet changed at this time as well? Some other…

I am pretty sure my diet stayed pretty tight, as I monitor my caloric intake using my smartphone and it remained pretty consistent. Obviously this could be skewed for other reasons so it's not gospel. The "much" is carrying a lot of weight, so to speak, in your comment. As a reference I went from running ~25 miles a week to just walking a fraction of that as I've recovered. I did keep up my other non-cardio calisthen…

That's very interesting because with some more napkin math...

If we assume 3500 additional calories is 1 lb of fat stored on your body, then 3500/300 = 11.6 days you gained 1lb

Assuming 6 months is 180 days, then 180/11.6 = 15.5 lbs over 6 months

Re: Scientist busts myths about how humans burn calories

#683

Post by dahart »

MuffinFlavored wrote: post #235
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…

> losing weight happens by eating less If your BMR is say... 1,800 calories a day and you exercise 300 calories worth... do you just get 300 calories hungrier to offset the exercise?

Yeah more or less exactly right. It’s maybe not hungrier per se, but I was eating until I felt “full”. I found out there are a couple of different problems with that. Waiting until “full” means I’m not stopping early and not able to put myself into calorie deficit, which is a longer-winded way of saying yeah I just got 300 calories hungrier. But I also have discovered that I’m a little miscalibrated on what “full” should feel like. I was eating a little past full and into a deeper level of satiated. Meaning, in short, slightly overeating.

And to add a little color, my exercise routines have usually involved more than 300 cals of workout, probably closer to 700-1000. This is important, because when not tracking the extra food, it’s really easy to overshoot 1000 calories by 300. The exercises have varied a lot over the years, from running and biking to weight lifting and sports like soccer & ultimate frisbee. I’ve been aiming for around 3 days/week workouts for like 10-20 years. I have periods of less, and occasionally more (especially in the summer) and have managed to keep it up more or less consistently. I eat more when exercising, but never lost weight consistently until I learned the open secret, that for me monitoring intake is what makes exercise work as a weight loss tool.

Re: Scientist busts myths about how humans burn calories

#684

Post by naasking »

alistairSH wrote: post #624
naasking wrote: post #620

Earlier quoted context omitted.

Running doesn't burn as much as you think because your muscles store energy elastically on the eccentric phase of each step. This removes a lot of energy needed for the subsequent concentric part. Contrast this with cycling which is pretty much all concentric contractions.

Interesting, hadn't considered that aspect. Just goes to show how complicated and counter-intuitive this can be.

Evolution is great at optimizing! Running is so efficient for humans that some human tribes use it to hunt (persistence hunting). They literally run their prey to exhaustion then just walk up and kill them.

Re: Scientist busts myths about how humans burn calories

#685

Post by dahart »

csee wrote: post #317
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…

This misses the point of the article, it isn't that you unconsciouly eat more when you exercise, it's that moderate exercise simply doesn't burn that many calories (if any) once your body is accustomed to it.

Yeah, that’s not really true, because physics. The article’s “myth busting” is overstating the evidence. Human metabolic systems do have some adaptation. It slows down a bit when we’re not eating enough to maintain status quo, and it speeds up a bit when we’re exercising more. But it doesn’t come anywhere close to compensating for all of the effort. If you read more carefully, you will find that the article is talking about compensating behaviors, in fact quite similar to what happens to me when I overeat. The other compensating behavior mentioned in the article is becoming more sedentary after exercise, this has some of the same effect as eating, however it’s far easier to accidentally over-compensate by eating than by following exercise with couch time.

I absolutely unconsciously eat more when I exercise. I know because I measured it. And once I measured it and focused on exercising while also eating a constant amount, surprise surprise, I actually lost weight. This is well known to many many people, well studied and understood, and has a metric ton of actual data to back it up. If this article is claiming to challenge that, then this article is wrong. (But IMO it’s not actually challenging known physics, it’s just written in a misleading way.)

Re: Scientist busts myths about how humans burn calories

#686

Post by coryfklein »

obpe wrote: post #682
JeremyNT wrote: post #677

Earlier quoted context omitted.

I am pretty sure my diet stayed pretty tight, as I monitor my caloric intake using my smartphone and it remained pretty consistent. Obviously this could be skewed for other reasons so it's not gospel. The "much" is carrying a lot of weight, so to speak, in your comment. As a reference I went from running ~25 miles a week to just walking a fraction of that as I've recovered. I did keep up my other non-cardio calisthen…

That's very interesting because with some more napkin math... If we assume 3500 additional calories is 1 lb of fat stored on your body, then 3500/300 = 11.6 days you gained 1lb Assuming 6 months is 180 days, then 180/11.6 = 15.5 lbs over 6 months

Also the article did say specifically that the hunter-gatherers were within 10% TEE of the average US person. That's order-of-magnitude in line with the 300 calories/day, given that the NHS recommended calories/day for men is 2500 and 10% of that is 250 calories.

Re: Scientist busts myths about how humans burn calories

#687

Post by wolverine876 »

rhinoceraptor wrote: post #625
wolverine876 wrote: post #190

Earlier quoted context omitted.

> It took me several decades too long to understand the obvious, that exercise is for building strength, and losing weight happens by eating less. Exercise does much more, and does have some impact on weight, according to the next paragraphs of the article: But Thyfault warns that message may do more harm than good. People who exercise are less likely to gain weight in the first place, and those who exercise while th…

> People who exercise are less likely to gain weight in the first place People who exercise are inherently more health conscious in the first place, so that's not surprising. That doesn't mean the exercise is responsible for that.

Did the research control for that?

Re: Scientist busts myths about how humans burn calories

#688

Post by icedistilled »

NautilusWave wrote: post #259
icedistilled wrote: post #171

Earlier quoted context omitted.

I'm baffled by the take away from the study. If a sedentary person and an athletic person burn about the same, doesn't that just mean the sedentary person's energy is being spent on maintaining and accumulating fat mass? But why is that waffled about instead of stated? Major Edit: more concise example >As the athletes’ ran more and more over weeks or months, their metabolic engines cut back elsewhere to make room for…

If storing fat burned calories, it would make for a pretty poor way to store calories...

Cells don't live for free and fat is stored in cells. So yes storing fat burns calories, just far less than muscle. And that's just the direct expenditure.

I see a few numbers thrown out for how many calories a pound of fat burns a day, but that direct burn is only one way additional fat would lead to energy use. A heavier person while less "active" will burn more during day to day due to carrying a heavier mass. I'm sure there's plenty more ways but I'm not going to go do a deep dive.

Re: Scientist busts myths about how humans burn calories

#689

Post by francisofascii »

TulliusCicero wrote: post #391
elvis10ten wrote: post #224

Earlier quoted context omitted.

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 bi…

My girlfriend, who was not trying to diet, lost about 20 lbs when she studies abroad in Italy, because she had to walk everywhere.

Re: Scientist busts myths about how humans burn calories

#690

Post by throwaway09223 »

nradov wrote: post #681
throwaway09223 wrote: post #672

Earlier quoted context omitted.

It seems doubtful the measurements would be far off. The numbers fit with the expected 50 or so calories per mile biked.

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.

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