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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

#151

Post by makeitdouble »

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

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

Re: Scientist busts myths about how humans burn calories

#152

Post by dpark »

KallDrexx wrote: post #139
djtango wrote: post #60

Earlier quoted context omitted.

Which is laughably ridiculous when you start considering the extremes like Michael Phelps eating 10kcal for breakfast. The issue is the uptick in energy burn is unintuitive especially in the world energy dense high-processed food As an ex once put "you have to run 5 miles to earn a cupcake - totally not worth it!"

> Which is laughably ridiculous when you start considering the extremes like Michael Phelps eating 10kcal for breakfast I think you are missing the fundamental part of the article about the calorie expenditures being adjusted based on non-fat body mass. So, yes Michael Phelps eats a lot of calories, but him (and other pro athletes) have spent their lives building muscle and keeping fat reserves down. Michael Phelps I…

> Michael Phelps I think is at a 5% body fat

No way. 5% is well below optimal for athletic performance. At 5% you’re looking at developing health problems. This is the range bodybuilders aim for on stage because they care about looking shredded more than they care about having joints that work.

Phelps was reportedly 8% when he won all those medals in Beijing.

Re: Scientist busts myths about how humans burn calories

#153

Post by twoWhlsGud »

PaulDavisThe1st wrote: post #74
gameswithgo wrote: post #63

Earlier quoted context omitted.

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.

Riding a bicycle? It's roughly 5x more efficient than running or walking. If you want to lose weight from cycling, you're going to have ride significantly further than 50 miles a day.

Or live somewhere where you can climb hills on the way to the grocery store... : )

Re: Scientist busts myths about how humans burn calories

#154

Post by joeld42 »

PaulDavisThe1st wrote: post #74
gameswithgo wrote: post #63

Earlier quoted context omitted.

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.

Riding a bicycle? It's roughly 5x more efficient than running or walking. If you want to lose weight from cycling, you're going to have ride significantly further than 50 miles a day.

Depends. I can do 15 miles at a leisurely pace on a social ride and not burn very many calories. I can do those same 15 miles at a fast pace and burn 2-3x as many calories. And then you can throw in some hills too.

I lost 80 pounds over the last couple years with riding average of 12 miles a day.

Re: Scientist busts myths about how humans burn calories

#155

Post by EGreg »

OK, so then, what does make people lose weight? And all those pounds come off? How do you help someone who is mildly obese go to having a bikini body?

I read you lose calories by breathing heavily, as the CO2 leaves your body, etc.

In my opinion, it's not about aerobics, but building muscle mass. Women who pack on muscle burn more calories at rest than women who don't. They may weigh the same but the fat is replaced by muscle. (Women need fat, though, so too much of this can be bad.)

Re: Scientist busts myths about how humans burn calories

#156

Post by EGreg »

neltnerb wrote: post #89
dahart wrote: post #61

Earlier quoted context omitted.

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.

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)

Re: Scientist busts myths about how humans burn calories

#157

Post by nradov »

_9omd wrote: post #65
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…

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…

You have a few correct points but are mostly spreading misinformation. Repeated exercise will only improve efficiency by a few percent at most, and then only for certain activities. For cycling, efficiency hardly improves at all. The calories shown on gym equipment are often nonsense but the latest generation of fitness trackers are reasonably accurate and can be worn 24/7.

You have to get into really long cardio sessions with no carbohydrate supplements before that has any significant catabolic effect. This is not a concern for casual athletes.

Strength training is great, but it should be combined with some form of cardio in a comprehensive fitness program.

Re: Scientist busts myths about how humans burn calories

#158

Post by ngngngng »

throwaway09223 wrote: post #118
geoduck14 wrote: post #70

Earlier quoted context omitted.

>A lot of people know this already, so it’s not busting everyone’s myths It is still worth mentioning - because it is so easy to overlook. Some simple math: if I go all out on a row machine for 30 minutes, I'll burn 300 calories. If I eat 2 extra slices of pizza, it is easiely 300 calories If I swap a turkey sandwich with healthy options, I can reduce my linch calories by 300 - and I can save even more during dinner…

> if I go all out on a row machine for 30 minutes, I'll burn 300 calories. A stationary bike at a steady 20mph pace is about 500 calories in 30 minutes. That's really significant. An hour will erase about a third of a normal person's diet. When I used to do heavy training (long distance running, weight training) I would eat close to 8k calories a day and I was in fantastic shape. Eating more was necessary to survive,…

An hour will replace a third of a healthy persons diet.

Fats are the secret to obesity, hands down. I have a remarkably small appetite and I can easily down 1000 calories of ice cream in a single sitting (a single pint of Ben and Jerry's. You can row like crazy for 30 minutes, but if you have two extra candy bars, it's meaningless.

Re: Scientist busts myths about how humans burn calories

#159

Post by wyldfire »

makeitdouble wrote: post #151
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 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

It seems to me that CICO is less of a myth and more of an "incomplete model." Having a model is an improvement over no model at all, even if it's oversimplified IMO. For very overweight people it probably doesn't matter quite as much.

If you had an accurate & sophisticated model for how the foods one eats contribute to their fitness / health / appearance, it probably would be too unwieldy to apply. A daily sum of calories, however, is simple enough to keep in your head or paper or an app.

Re: Scientist busts myths about how humans burn calories

#160

Post by darksaints »

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…

I believe him. As a nowhere-near-olympics division 1 swimmer, I had developed a major weight loss problem my freshman year. I actually was required to log my calories and meet with a sports nutritionist weekly. After 6000 calories a day, I was shoving so much food in my mouth, I felt like it wasn't possible to eat any more than I did. She prescribed Snickers bars as a way to top off my calories every day without contributing too much to feeling full. I was targeting 7000 calories a day, and I don't think I ever consistently reached that goal, but around that time my weight stabilized.

There are a lot of people who maintain a high degree of fitness, and for them I can imagine 4000 calories is about right. But there are some types of training that are consistently pushing your physical limits. I don't have any sort of data to back this up, but it has long been my theory that the reason why elite athletes can burn so many calories is because they aren't actually burning them in the traditional sense of cells oxidizing chemical energy to create work...they've crossed over into the territory of muscle tissues being torn up and resynthesized so much that your body can no longer do so efficiently.

As an analogy, typically in manufacturing there are always efficiencies that can be extracted. But in very mature industries where there aren't any easy efficiencies to eek out of the system, you have to start making tradeoffs. One common tradeoff is throughout vs yield. You can increase your throughout, but in order to do do so, you have to cut corners on processes and subsequently increase the total amount of waste in the process.

And as a "maybe this is related" data point: 82% of marathon runners suffer from Acute Kidney Injury. Your kidneys have one job: waste disposal. It would be easy to infer that at the boundaries of human conditioning, the kidneys aren't up to the task of processing all of the waste that the body is producing.

https://medicine.yale.edu/news-article/marathon-running-and-...

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