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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

#621

Post by tom-thistime »

koheripbal wrote: post #602
tom-thistime wrote: post #581

Earlier quoted context omitted.

Yes. And no. Bro science is more or less useless. But the article isn't super useful either. Calories burned are "adjusted for nonfat body mass." Adjusted how? Fat stores energy. Food adds energy. Exercise uses energy. Those aren't "myths." The article (not talking about the scientist) is very difficult to understand, but it seems to come down on the "myth" side of that dilemma. Mostly. Kind of.

When you do the math, your body turns out to be extremely efficient. Two full hours of very hard exercise burns the equivalent of one average sized lunch meal. Skipping meals/cutting calories is, by far, the easiest way to lose weight.

Let's get specific.

Maybe your suggestion might be a cataclysmic -1000 calories per day, either by (a) skipping a large lunch completely and not changing exercise, or (b) by doing those two hours of hard exercise and not changing diet. That person will tend to lose around two pounds a week either way over the long term. (Of course I don't really know what numbers you have in mind.)

But losing two pounds a week is insane.

So let's look at safer, more normal behavior. Call it -300 calories per day: either cutting diet by a medium order of fries each day (and keeping exercise fixed) or doing 40 minutes of moderate exercise (and keeping diet fixed). Then the person will tend to lose a pound about every 12 days over the long term. That is still rapid weight loss either way.

If the same person starts riding a bike 40 minutes a day but doesn't count calories, the results could be anything. They could easily put on weight. Who knows?

Re: Scientist busts myths about how humans burn calories

#622

Post by goda90 »

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.

Re: Scientist busts myths about how humans burn calories

#623

Post by jnsie »

mrleinad wrote: post #594
artdigital wrote: post #378

Earlier quoted context omitted.

My advise: (as someone who does a lot of working out and calorie control) 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. And that's basically it, once you know what your TDEE is, eat under it to create a caloric deficit and you will lo…

I'd love to count calories. I'm just too lazy to measure and research everything I eat, and the alternative is to have only processed foods that are labeled. It's too bad that we can't just live on Soylent (the actual beverage, not the thing from the book)

I was very excited about Soylent years ago...until I tried it. I really disliked the flavor, so wouldn't have stuck with it regardless, but what really surprised me was how much I enjoy the act of sitting down and eating a meal. Soylent filled me up, but it never satiated me. Regardless of the time savings and predictability, I missed the act of eating, if that makes sense.

Re: Scientist busts myths about how humans burn calories

#624

Post by alistairSH »

naasking wrote: post #620
alistairSH wrote: post #585

Earlier quoted context omitted.

seems easier to burn energy on a bike than other forms of exercise I'm not sure this is true. Cycling isn't weight-bearing (you're sitting down) and only engages the large leg muscles. Running and rowing likely provide more calorie burn for a given RPE (rate of perceived exertion) over a fixed time period. Running because it's weight-bearing; rowing because it engages more muscle groups. That said, you can probably c…

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.

Re: Scientist busts myths about how humans burn calories

#625

Post by rhinoceraptor »

wolverine876 wrote: post #190
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 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.

Re: Scientist busts myths about how humans burn calories

#626

Post by mmmpop »

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…

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 cardio, I'd be able to (and want) to eat an extra 500-600 calories to compensate, and still lose weight.

I swear I can maintain weight eating more than what I supposedly burn while active, which could make sense if you buy into the whole "your metabolic rate can be work-hardened" concept.

Re: Scientist busts myths about how humans burn calories

#627

Post by xzel »

mrleinad wrote: post #594
artdigital wrote: post #378

Earlier quoted context omitted.

My advise: (as someone who does a lot of working out and calorie control) 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. And that's basically it, once you know what your TDEE is, eat under it to create a caloric deficit and you will lo…

I'd love to count calories. I'm just too lazy to measure and research everything I eat, and the alternative is to have only processed foods that are labeled. It's too bad that we can't just live on Soylent (the actual beverage, not the thing from the book)

With a 10 dollar scale and an App like Lose It, it is pretty easy. They have both things with UPC codes for easy look up and standard foods, for example brown rice or salmon. I keep track and probably spend less than 5 minutes a day getting everything down. Obviously it will be difficult at a restaurant unless you want to bring a scale with you or beg the wait staff but largely they won't mind and if you're order grilled chicken and veg most likely they won't mind measuring the chicken for you. Anyways, the stuff on labels are estimates so the whole process has some moderate error so as long as you estimate fairly you don't have to worry about being crazy accurate.

Re: Scientist busts myths about how humans burn calories

#628

Post by ClumsyPilot »

mantas wrote: post #458
1_player wrote: post #382

Earlier quoted context omitted.

> What's so controversial about it? Your body burns incredibly more energy just "being there" than you burn moving about. Exercise certainly increases your calorific expenditure, but it's much easier to ingest less fuel than to run 5 more miles because you had a portion of fries. There are benefits in exercise, apart from the obvious ones the raising of the baseline metabolic expenditure, because muscles are expensiv…

> Your body burns incredibly more energy just "being there" than you burn moving about. Bullshit. My body goes through 1600-ish kcal on an idle day. If I go out on a 4h steady bicycle ride (= 100km), I go through 2000 kcal on ride alone. That’s much more than my body burns just being there.

"If I go out on a 4h steady bicycle ride (= 100km), I go through 2000 kcal on ride alone."

What do you mean 'on that ride alone', are you doing more than 4 hours of excersise a day, every day? Because that's like 0.1% of the population, most can't even fit that in their diary, let alone have the stamina/etc.

Average bloke goes to the gym for an hour couple times a week, at that level you calorie consumption is basically unchanged - its withing an error margin of natural variability of food you eat.

Re: Scientist busts myths about how humans burn calories

#629

Post by etc_etc »

mrleinad wrote: post #594
artdigital wrote: post #378

Earlier quoted context omitted.

My advise: (as someone who does a lot of working out and calorie control) 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. And that's basically it, once you know what your TDEE is, eat under it to create a caloric deficit and you will lo…

I'd love to count calories. I'm just too lazy to measure and research everything I eat, and the alternative is to have only processed foods that are labeled. It's too bad that we can't just live on Soylent (the actual beverage, not the thing from the book)

MyFitnessPal does a pretty good job. You can scan barcodes and it'll (usually) have the calories and macros. Also just having a set of scales on hand makes it a lot more accurate!

Re: Scientist busts myths about how humans burn calories

#630

Post by amanaplanacanal »

EGreg wrote: post #156
neltnerb wrote: post #89

Earlier quoted context omitted.

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.

Intermittent fasting can help repair a lot of things in your body, make you live longer, etc. Vegans live on average 10 year longer! The hunger you feel the first day btw is not "real" hunger, it's just your stomach growling and you being used to eat. After you ignore hunger for 3 days, your body stops wanting food. That's if you want to do a cleanse. (I've never done one though)

> Vegans live on average 10 year longer!

Interesting if it's actually true. I doubt there are any good studies about that, though.

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