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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

#141

Post by dpark »

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 consideration post-exercise burn, weight lifting will at best get you too the same efficiency as aerobic exercise.

Example data from: https://www.medicalnewstoday.com/articles/323922#calculating...

Weightlifting is great but it’s not better for burning calories. It’s much better for retaining muscle while dieting, though.

Re: Scientist busts myths about how humans burn calories

#142

Post by happytoexplain »

urthor wrote: post #114

The thing is, exercise still reduces appetite. It raises the blood sugar levels as the body supplies the muscles with carbohydrates, and triggers a complementary response in appetite hormones. Finally, and most importantly: Exercise releases dopamine. Dieting is universally a mood killer, because kilo-joule deficit equals starvation. So whilst it does not directly impact weight loss. It still makes it (a bit) easier.…

>exercise still reduces appetite

This was one of the big surprises for me. When I'm exercising regularly, food tastes better, and yet I'm satisfied with less of it.

Re: Scientist busts myths about how humans burn calories

#143

Post by dpark »

throwaway09223 wrote: post #130
dpark wrote: post #99

Earlier quoted context omitted.

I would really like to see raw data because it feels like the story being told can’t possibly be complete. This in particular feels really hand wavy: “After weeks of training, they barely burned more energy per day when they were running 40 kilometers per week than before they started to train.” What does “barely” mean? 40km/week isn’t that much in terms of calorie burn. The 100 calories/mile rule of thumb says this…

40km/wk is only 3.4 miles/day. It's only a half hour of moderate exercise a day. It sounds like the study didn't actually measure a significant exercise workload.

It was measuring women who were sedentary and trained for half marathons. For someone who was previously sedentary, 3.4 miles/day is an enormous amount of exercise. It’s certainly far more than the average American gets.

It’s not that much in terms of calories. It is a lot of physical activity for a modern human in a developed nation.

Re: Scientist busts myths about how humans burn calories

#144

Post by quantified »

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…

Some levels, yes, appetite-suppressing. When appetite returns, it can be with a vengeance.

Re: Scientist busts myths about how humans burn calories

#147

Post by nu11ptr »

onethought wrote: post #131
nu11ptr wrote: post #93

Earlier quoted context omitted.

If you fall into a routine CICO isn't that difficult in practice. First, while sleep/stress definitely impact the equation unless you are at an unusual life crisis, the ups and downs mostly balance out over time. Second, I don't recommend counting calories, at least not in the traditional way. Instead, eat a fairly standardized diet at least on a weekly basis, so roughly the same meals (doesn't have to be exact). Eat…

> Now, to lose weight simple subtract 500 calories per day from what you eat I appreciate you are trying to be helpful. But most of what you said assumes a certain level or privilege (resources time/money/ableness) that the vast majority of people don't have. People working long hour jobs, or double jobs, or balancing kids/parent responsibilities. Often fast food is the only obvious option, and people aren't buying i…

Fair point, and and definitely some truth to that. I almost added "This works for me, your mileage may vary" disclaimer.

I will say that what I said above is _relative_, so if you go out for fast food "more than you should" than that becomes your baseline. Anything can be a baseline, even if not a healthy one.

I also know at least one person who has tried it and swears up and down it just doesn't work for them.

Re: Scientist busts myths about how humans burn calories

#149

Post by libraryofbabel »

PaulDavisThe1st wrote: post #80
libraryofbabel wrote: post #42

Earlier quoted context omitted.

> 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. An interesting source here is the Fiennes and Stroud expedition to cross Antarctica in 1992. Stroud (a physician) actually tested how many calories they were burning each day usi…

Another related extreme case was the first person to solo-ski to the north pole. They pre-loaded, mostly on olive oil, packing on tens of kg in body fat, all of which (and more) was gone by the time they were done. I don't recall the daily calorie expenditures but it was gigantic. They did this because there is some mechanical advantage carrying a good chunk of one's energy supply directly on your own bones rather th…

Fiennes and Stroud lost about 25kg each crossing Antarctica; I don’t know if they pre-loaded beforehand (hopefully they did, losing that much!) but they certainly ran a deficit as a strategic trade-off against their sled weight. Hauling a kilo of fat on a sled is definitely less efficient than carrying it on your own body.

Supposedly their calories during the expedition were primarily from butter, which they mixed into every food and even ate on its own. Apparently you get used to it.

Re: Scientist busts myths about how humans burn calories

#150

Post by nu11ptr »

timr wrote: post #137
nu11ptr wrote: post #93

Earlier quoted context omitted.

If you fall into a routine CICO isn't that difficult in practice. First, while sleep/stress definitely impact the equation unless you are at an unusual life crisis, the ups and downs mostly balance out over time. Second, I don't recommend counting calories, at least not in the traditional way. Instead, eat a fairly standardized diet at least on a weekly basis, so roughly the same meals (doesn't have to be exact). Eat…

I have also done almost exactly this process, and it worked for years to regulate my weight. But then I hit a plateau (a high plateau, not a low one) where I was unable to drop weight no matter how low I cut my calories. I started at a range that I knew had worked in the past, and lowered it over the course of weeks, well past the point where I was miserable. I even tried more complicated things, like varying my inta…

I've only used this to go up/down +-10 lbs seasonally (although I did permanently drop 40lbs on a one time calorie restriction diet about a decade ago, but not exactly this method). One thing to keep in mind (you probably thought of this already) is your calorie burn goes down as you lose weight. So a 160lbs person takes in less calories to maintain even weight than a 200lbs person, thus you may need to reassess baseline for longer cuts. Beyond that, no idea, and yes, everyone is individual.

I will say the whole time I have used this I have trained with weights extensively (5 days/week standard 3x sets per exercise body building routine). I do not know how much or little this plays into it, but definitely helps with the fat/muscle ratio (obviously).

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