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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

#171

Post by icedistilled »

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…

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 the extra exercise costs, Pontzer says. Conversely, if you’re a couch potato, you might still spend almost as many calories daily, leaving more energy for your body to spend on internal processes such as a stress response.

Re: Scientist busts myths about how humans burn calories

#172

Post by taeric »

gameswithgo wrote: post #116
taeric wrote: post #81

Earlier quoted context omitted.

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.

I know such a person which is why I mentioned it. That vast range of human physiology is fascinatingly wide. He also is very aerobically gifted, possibly related things. (efficient engine, but not confirmed with testing, maybe just a big engine and loves food)

Completely fair.

Thinking on it, if food is,I eat it. Any pizza is a personal pizza, if you like pizza. :)

Still. Guessing most folks that can ride fifty miles are not overweight.

Re: Scientist busts myths about how humans burn calories

#173

Post by standardUser »

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…

People often conflate body weight with how they want to look, and when they say they want to lose 20 pounds, what they really want is for their body to look different in some specific ways. Exercise is a very effective way to alter the appearance of our bodies, and far more versatile than diet alone.

Re: Scientist busts myths about how humans burn calories

#174

Post by gunshai »

When I want to lose weight I do this one simple thing ... I stop eating as much.

Fasting really isn't all that difficult once you train your brain around it.

You simply can't gain weight if you are consuming less. You don't need a triple PhD to understand the law of conservation of mass.

If you want to read something fairly extreme I suggest the following.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2495396/

Now this isn't a guide on how to lose weight, but it should give everyone some insight into what the human metabolism is capable of.

Re: Scientist busts myths about how humans burn calories

#175

Post by dugite-code »

dpark wrote: post #141
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…

Lifting weights is a poor way to burn calories. It’s a great way to build muscle and be healthier, but lifting weights is less efficient than aerobic exercise in terms of pure calorie burn. e.g. Moderate intensity aerobic exercise burns 200-300 calories in 30 minutes. Moderate intensity weightlifting is 90-130 in the same time. You need vigorous weightlifting to get up to 250 in 30 minutes. Even taking into considera…

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 was from the article it read that they focused on running as the primarily measured exercise. So it might not provide the best full picture when looking at other exercise methods.

Re: Scientist busts myths about how humans burn calories

#176

Post by 1123581321 »

makeitdouble wrote: post #161
1123581321 wrote: post #100

Earlier quoted context omitted.

I wouldn't necessarily advise someone to diet without starting exercise. Exercise encourages healthier eating in a few physical ways, and for many the two are part of a mental lifestyle self-image which admittedly shouldn't exist but can still motivate. I'm also skeptical of that balance theory. A exercised body would produce more reliable eating and satiation signals to aid in balance, if 'balance' is even how the n…

The twist is that if you get healthier by changing your eating habits, it will probably be easier for to start/increase exercise, and will continue to make you healthier while you take on exercising. Better eating is I think the most impacting thing you can do, exercising being the close second.

Absolutely. I think starting with either is totally viable, and it sounds like we agree that the only combination that probably won't work is exercising but never getting around to changing a bad diet.

Re: Scientist busts myths about how humans burn calories

#177

Post by emodendroket »

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 know this isn't rigorous but it definitely matches up with my personal experience -- I'll be hungrier, often ravenously so, after strenuous activity.

Re: Scientist busts myths about how humans burn calories

#179

Post by dahart »

thisisonthetest wrote: post #162
makeitdouble wrote: post #151

Earlier quoted context omitted.

> losing weight happens by eating less To note, when they refer to "diet" it's probably not about "eating less" or popular "on a diet" interpretation. Good and bad diets also aren't as simple as the "CICO" myth

CICO is almost as pernicious and ubiquitous. It really grinds my gears when people try to use “intuition” to understand something super complex with no data at all. People talk about “metabolism” the same way. Say the word “toxins” around me and I will fight you in the streets.

Except we have literal truckloads of data on calories and metabolism. Like a lot of human physiology, these things come with Normal (Gaussian) distributions in the human population. There are averages and deviations we can talk about, without having to understanding anything about the inner workings of the human body, right?

I couldn’t agree more that CICO is a super blunt instrument, but it actually does work, because the alternative we’re comparing to is not tracking input & output at all. You can be a lot wrong, and it’s still better than completely wrong, right? :P Like the amount of noise in my calories estimates is probably at a minimum 10%-15% wrong at all times, same goes for expenditure (maybe even worse) but it seems like the important part isn’t actually the number, it’s the act of establishing and sticking to a budget. For me, mentally, it was the realization that my feelings on hunger and satiety were actually mis-calibrated. This helped me get over the idea of being hungry, and helped me realize the goal wasn’t to overcome hunger, it was to get used to something closer to the correct amount of food.

Re: Scientist busts myths about how humans burn calories

#180

Post by dpark »

dugite-code wrote: post #175
dpark wrote: post #141

Earlier quoted context omitted.

Lifting weights is a poor way to burn calories. It’s a great way to build muscle and be healthier, but lifting weights is less efficient than aerobic exercise in terms of pure calorie burn. e.g. Moderate intensity aerobic exercise burns 200-300 calories in 30 minutes. Moderate intensity weightlifting is 90-130 in the same time. You need vigorous weightlifting to get up to 250 in 30 minutes. Even taking into considera…

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 recall correctly).

Calories burned from extra muscle are not as important as people like to imagine. It’s like cardio. Do enough and it has an effect, but in terms of what normal humans should expect, it’s not going to do much, because normal people are simply not going to build enough muscle to matter much. The average person isn’t going to build 40 extra pounds of lean mutant. Most of the claims about how many calories muscle will burn are also not backed up by any science so far as I can tell.

I do agree that this article doesn’t cover a lot of stuff, though. I’m doubtful about the stuff claimed even about running because it feels so have wavey. The one potentially compelling study was on women who went from sedentary to running half marathons and the claim is that they “barely” burned more calories at the end than at the beginning, but “barely” is almost meaningless. Plus they did burn more so the whole thesis is in question.

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