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Scientist busts myths about how humans burn calories

science.org

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Re: Scientist busts myths about how humans burn calories

#81

Post by taeric »

gameswithgo wrote: post #63
taeric wrote: post #37

Earlier quoted context omitted.

Yeah... I don't know that it is that simple. In the summer when I bike twenty miles a day, I am eating far more, and still losing weight. Don't get me wrong, I know that the easiest way to lose weight is to limit calorie consumption. I also know that a buffet of 1800 calories going to a bike ride helps a ton.

its possible to work out enough that compensative eating is not possible, but very few people work out that much, and some people have amazing eating powers, such that even riding a bike 50 miles a day isn’t enough to stop them being fat unless they also count calories.

I'm guessing there are very few folks getting fifty miles a day in, and still heavily overweight. Possible, to be sure. Just very unlikely.

Re: Scientist busts myths about how humans burn calories

#82

Post by buzzard1 »

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…

[dead]

Re: Scientist busts myths about how humans burn calories

#83

Post by PaulDavisThe1st »

JackMorgan wrote: post #44
themodelplumber wrote: post #2

> Exercise doesn’t help you burn more energy on average; active hunter-gatherers in Africa don’t expend more energy daily than sedentary office workers in Illinois; pregnant women don’t burn more calories per day than other adults, after adjusting for body mass. I love this intro. > His message that exercise won’t help you lose weight “lacks nuance,” says exercise physiologist John Thyfault of the University of Kansa…

Some friends and I are currently doing a thru hike of the Appalachian Trail, and only ten days in the four of us clocked 7, 8, 10, and 17 pounds lost... But we're hiking 6+ hours a day with heavy packs. We've been eating easily ~3000kcal each daily. I think at the extreme edges, nutrition science is a lot less well understood. We were very surprised to see we'd lost anything at all, as we're stopping to eat 300 calor…

6hrs a day @ 3 mph = 18 miles per day, 100 calories per mile without packs = 1800 calories per day on top of basal metabolic needs. Given your user name, I'd guess that you're male, and given that you're hiking the AT and have already started, I'd also guess that you're younger rather than older, so I'd peg your basal metabolism at around 2200-2400 calories. Add in the packs and the hills, and it should be clear why you're losing weight.

Re: Scientist busts myths about how humans burn calories

#84

Post by PaulDavisThe1st »

kevin_thibedeau wrote: post #78
dugite-code wrote: post #40

Earlier quoted context omitted.

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…

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.

Cycling is roughly 5x more efficient than running/walking for similar effort. Thinking you will lose much weight by cycling is generally mistaken, unless you plan to cycle very long distances or are extremely obese already and do very little existing exercise (and this is discounting most of what TFA is saying too).

Re: Scientist busts myths about how humans burn calories

#85

Post by desmosxxx »

voisin wrote: post #8
themodelplumber wrote: post #2

> Exercise doesn’t help you burn more energy on average; active hunter-gatherers in Africa don’t expend more energy daily than sedentary office workers in Illinois; pregnant women don’t burn more calories per day than other adults, after adjusting for body mass. I love this intro. > His message that exercise won’t help you lose weight “lacks nuance,” says exercise physiologist John Thyfault of the University of Kansa…

> Combining this with the fact that Everest climbers are apparently eating 10K+ calories a day and then up to around 20K on summit day, I have to wonder how these facts jive...if they can really temporarily push the limit, for how long, etc. I think a lot of these stats are myths meant to accentuate the difficulty of the task. Pontzer’s book discusses Michael Phelps and the lack of an actual source to the rumours he…

So I'm not sure about everest climbers, 20k sounds pretty crazy.

But I can speak first hand as a former athlete who has had access to NFL players and Olympians. 8-10k during peak active training happens all the time

Long term average might be 4-5k.

You have to remember that these people are often on PEDs that allow them to train all day.

Shit I was a serious powerlifter back in the day and would routinely eat 6-7k calories (weighed) during 2adays depending on how my weight was fluctuating. Add some more height, PEDs, and cardio and I'm almost there.

I think the difference between what is mentioned in the article is #1 obviously PEDs #2 body breakdown and recovery, which might be more in e.g. lifters and swimmers than long distance runners

Re: Scientist busts myths about how humans burn calories

#86

Post by dpark »

josefrichter wrote: post #66
dpark wrote: post #26

Earlier quoted context omitted.

> If you start exercising at the same time, you are throwing your body drastically off current balance and it’s probably much harder to find a new one. This is for sure a [Citation Needed] claim. Exercise has been shown in numerous studies to be health protective and also to be muscle maintaining. I would love to know why you think exercising is not a net positive. I expect that greater than 99% off doctors, nutritio…

The point is don’t try to change everything at once. I am not questioning health benefits of sports. But change of diet is a big change - not only biologically, but also mentally, logistically, practically, financially, etc. Change of exercise is equally massive change. It’s kinda logical that trying to juggle too many things at once is more likely to fail.

This is an entirely different thesis. You said that starting diet and exercise together is harder in terms of your body finding balance. Now you’re talking primarily about logistics and mental impact.

Re: Scientist busts myths about how humans burn calories

#87

Post by snowwrestler »

dpark wrote: post #23
idontwantthis wrote: post #9

Earlier quoted context omitted.

> it never really worked because I’d unconsciously eat to compensate The wild thing is he’s saying that’s not true either. He’s saying you never burned the extra calories in the first place.

Not sure why you’re getting downvoted. That is literally the thesis here, that calorie expenditure is essentially decoupled from exercise.

Total body calorie expenditure seems decoupled.

Exercise obviously must burn calories because work is being done. The body can’t overcome physics.

The nuance, and the surprising thing, is that other parts of the body seem to adjust their energy levels to compensate. If you don’t do a lot of exercise, something else burns calories. If you do exercise, the “something else” burns less.

What is the something else? That’s the mystery that still needs to be solved. And by extension, what are the limits of the something else? After all, there are well-documented examples of extreme athletes who consume lots of calories without gaining mass.

Re: Scientist busts myths about how humans burn calories

#88

Post by lhuser123 »

PaulDavisThe1st wrote: post #72
_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…

> 2) Your hunger will increase to compensate for the calories burned and you'll subconsciously eat more if not carefully tracking. This is also a oft-made claim that doesn't have much backing. Part of the point of the research described in TFA is that humans who face specific periods of energy expenditure during the day may often simply reduce energy expenditure during the rest of the day so that TEE remains roughly…

I have a bias towards the idea that we are very different, and it really depends on many unknown factors that apply only to one specific individual.

Re: Scientist busts myths about how humans burn calories

#89

Post by neltnerb »

dahart wrote: post #61
mannykannot wrote: post #29

Earlier quoted context omitted.

This is purely anecdotal, with a sample size of one even if it is right, but it seems to me, personally, that exercise suppresses my appetite to some extent. I can't say that this is even real, but if it is, my best guess as to why this might be is that the exercise subtly stimulates/irritates my gut such that I am de-motivated to eat, either by feeling full or subliminally 'sick to my stomach'. After running a marat…

You’re so lucky! I wish exercise made me less hungry. I’ve only felt that when going on very long multi-day hikes… being in severe calorie deficit and having almost nothing sound good to eat. Chocolate was one of the only things that I could stomach. Oh and once I went running about an hour after eating tomato soup, and halfway through starting heaving uncontrollably. But normally, running, gym time, weight lifting a…

For me I lose my appetite for about a half hour, I was taught it's simply blood from your stomach being used elsewhere. After a short recovery period I'm definitely extra hungry.
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