Scientist busts myths about how humans burn calories

> 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 Kansas Medical Center, who says it may nudge dieters into less healthy habits.

This is funny to me because my own logs reflect this going back to about 2015. I can more easily drop 10, 20, or however many pounds when not exercising than I can when exercising. That was a really weird one because it opened up a bunch of other problems.

One follow-on problem that came up quickly: How to develop skills requiring fitness during those times, or how to maintain endurance levels when you're intentionally lowering your exercise exposure so you can lose weight. That kind of situation is pretty interesting.

> Azy, a 113-kilogram (249 lb.) adult male (orangutan), for example, burned 2050 kilocalories per day ... When adjusted for body mass, (humans) burn ... 60% more than orangutans

Oh and

> “She burned 40% more energy per minute in the math test and 30% in the interview,” Pontzer says. “Think about any other process that boosts your energy by about 40%.”

This is really curious and fascinating stuff. Thanks op for posting.

PS:

> He calculates that the ceiling for an 85-kilogram man would be about 4650 calories per day.

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.

> “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 exercise my fat off, and it never really worked because I’d unconsciously eat to compensate. Once I tracked what I ate, exercise actually became more effective.

A lot of people know this already, so it’s not busting everyone’s myths, but we also do have a strange narrative surrounding exercise and weight loss that I bought into. It makes me wonder if we’re physiologically wired to be allergic to the idea of less food, from an evolutionary perspective, because being hungry is literally risking death to our alligator brains.

> 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.

Yeah, I'm not convinced the article passes the smell test.

Michael Phelps discussed his diet extensively, suggesting he ate 10k a day while training. Other athletes talk about similar meal sizes. This suggests that once they stop exercising (thus eventually losing lean muscle mass and requiring less calories) that they would not see a change in their weight, yet there are a lot of old fat athletes (possibly just of a certain generation) out there.

> 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 was eating gargantuan amounts during training.

I always wonder how much of what we consume is actually absorbed, specially when factoring gut microbiome and non-soluble fibers.