Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Scientist busts myths about how humans burn calories

science.org

Post reply on HN
Print view View original

41–50 of 753 posts

Re: Scientist busts myths about how humans burn calories

#41

Post by TheSpiceIsLife »

mannykannot wrote: post #29
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…

This is purely anecdotal, with a sample size of one even if it is right, but it seems to me, personally, that exercise suppresses my appetite to some extent. I can't say that this is even real, but if it is, my best guess as to why this might be is that the exercise subtly stimulates/irritates my gut such that I am de-motivated to eat, either by feeling full or subliminally 'sick to my stomach'. After running a marat…

some would argue that running a marathon isn't exercise and shouldn't be considered as such.

Whether any one in particular subscribed to that school of though or not, marathon running is an outlier event, and isn't what most people would consider as part of a regular, healthy, exercise regime that one might do many times a week.

Re: Scientist busts myths about how humans burn calories

#42

Post by libraryofbabel »

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.

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 using the doubly-labeled water method, and at one point (ascent to the polar plateau) it was up to 11k. So it is definitely possible to temporarily push the limit - as the article acknowledges - but these are exceptional circumstances.

Re: Scientist busts myths about how humans burn calories

#43

Post by dahart »

idontwantthis wrote: post #9
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 never really worked because I’d unconsciously eat to compensate The wild thing is he’s saying that’s not true either. He’s saying you never burned the extra calories in the first place.

That’s the part that’s at least slightly exaggerated, or giving a misleading impression. Exercise absolutely burns more than 0 calories, and I definitely was burning some. Calorie burn from exercise is straightforward to approximately measure, and many people walking around with iWatches and FitBits and heart monitors are doing so. What’s well known to many people is that exercise burns far fewer calories than you wish it did, and less than it feels like. ;) The article points out that aerobic exercise adjusts your RMR and it becomes more efficient over time. However, it does not become 100% efficient, even though the article seems to suggest it and doesn’t bother with any fine print. It doesn’t bother to differentiate between running and weight lifting either, and we adjust to those differently.

Re: Scientist busts myths about how humans burn calories

#44

Post by JackMorgan »

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…

Some friends and I are currently doing a thru hike of the Appalachian Trail, and only ten days in the four of us clocked 7, 8, 10, and 17 pounds lost... But we're hiking 6+ hours a day with heavy packs. We've been eating easily ~3000kcal each daily. I think at the extreme edges, nutrition science is a lot less well understood. We were very surprised to see we'd lost anything at all, as we're stopping to eat 300 calories almost every waking hour.

Re: Scientist busts myths about how humans burn calories

#45

Post by giantg2 »

nwiswell wrote: post #24
berdon wrote: post #22

Earlier quoted context omitted.

Anecdotally, I have absolutely ran off a bad diet. I burn ~150-250 calories a mile and have ran off 2000+ calories to eat what I wanted with no discernible increase in weight. Did this for years. In hindsight, it’s much easier on one’s knees to adjust your diet.

Yeah. Cyclists in the Tour de France typically eat 5000 calories a day, often more in particularly difficult stages. Obviously none of them have a weight problem. "Fun" fact: they also shit themselves on the bike. When you eat that much it's inevitable you're gonna have to poop it out, and it's a race -- you can't stop.

I think there's also some other physiological action that trigger defecation as a response during long duration high intensity exercise like marathons and bike races.

Edit: here

"It’s related to the fact that during periods of physical stress, the body shunts blood away from organs that are not necessarily critical at that moment,” Michael Dobson, D.O., a colon and rectal surgeon with Novant Health in Charlotte, North Carolina, tells Mental Floss.

https://www.mentalfloss.com/article/648541/why-marathon-runn...

Re: Scientist busts myths about how humans burn calories

#47

Post by weq »

pverghese wrote: post #38
wesleywt wrote: post #19

Earlier quoted context omitted.

You tracked what you ate was the key difference. Not the exercise. I did an experiment on myself. I deliberately did not do any exercise and changed my diet. I loss 5kg quicker on my diet than I did when I was running 10km regularly. I think its counter productive to see an obese person in the gym or running as this will certainly lead to injury. The narrative around weight loss should always be eat less calories and…

Not sure what was your starting weight. But 5 kg is within the realm of normal weight fluctuations over a week for an average American.

when u weigh 400lbs and eat forty twinkings and hour, sure, 5kg weekly fluctations may be normal.

Your fat because you consume to many caloiries for what you put out. Pretty simple.

I went week on/off vego, from being a meat eater near daily, dropped weight without adjusting anything else.

You are what you ate. You cant hide from it. If you look down and see some rolls, thats not cause you didnt exercise enough!

I went from doing gym weekly in my 20s, to my 30s where i dont touch consciously exercise at all yet im bigger, leaner, and have my abs back. My uncle, who at my ate became a fat bastard and never stopped; used to be a body builder on the roids. He had a sweet phsyic for about 1 year.

The easier way to make money in this world, is to fool fat people into thinking your product will let them have their cake, and eat it to. I say fat people the say way people refer to a drug addict. Its the same thing, cept your comfort blanket is legal and readyly accessible, 24/7/7, being pushed at you constantly whenever you look.

I say this as a child of a mother who was/is fat due to being in an abusive relationship with my father. She cheated through every diet she every did. Until she got her stomach stapled; when overnight she SHED weight, was no longer diabetic, and is currently 66yrs old and going strong (stapled around 49).

Re: Scientist busts myths about how humans burn calories

#48

Post by slt2021 »

basementcat wrote: post #31
nwiswell wrote: post #24

Earlier quoted context omitted.

Yeah. Cyclists in the Tour de France typically eat 5000 calories a day, often more in particularly difficult stages. Obviously none of them have a weight problem. "Fun" fact: they also shit themselves on the bike. When you eat that much it's inevitable you're gonna have to poop it out, and it's a race -- you can't stop.

The reduction in mass undoubtedly makes it easier to complete the remainder of the stage.

It might add some propulsion force if it is diarrhea

Re: Scientist busts myths about how humans burn calories

#49

Post by robotburrito »

nsxwolf wrote: post #36

This is very depressing. I find it incredibly difficult to lose weight dieting. And now it's telling me I just wasted all this money on a treadmill (and the effort it took to get it down into the basement).

It is not a waste. The benefit of being active by using that treadmill is huge in many ways not limited to just weight loss.
Post reply on HN