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

Little kids burn so much energy, they’re like a different species, study finds

sciencemag.org

Post reply on HN
Print view View original

51–60 of 118 posts

Re: Little kids burn so much energy, they’re like a different species, study finds

#51

Post by guerby »

tw04 wrote: post #11
Supersam654 wrote: post #8

Personally, I was more surprised by the various groups of people who _don't_ have higher metabolic rates: > Children’s metabolic rates stay high until age 5, but the rate slowly begins to glide down until it plateaus around age 20. Interestingly, adult rates are stable until age 60, when they begin to decline. After age 90, humans use about 26% less energy daily, Pontzer says. > The study also found that pregnant wom…

This seems almost unbelievable to me. Almost everyone I know, with a handful of exceptions I can think of, had a dramatic change in what I can only say was metabolism at 30 declining steeply to 40. I can tell you personally my ability to lose weight when exercising daily has decreased significantly since 30. If it’s not metabolism, then what? Diet and exercise are almost identical.

Insulin resistance slowly builds up with age.

Re: Little kids burn so much energy, they’re like a different species, study finds

#52

Post by [deleted] »

lordnacho wrote: post #47
hprotagonist wrote: post #6

> But children also burn out fast. This is well known in emergency medicine. Not only do kids burn out quick, they also burn out completely because they, unlike adults, don't keep a reserve. This applies to homeostasis, too. Consequently: young trauma victims that "look OK" need to be very closely attended to, because what you might be seeing is a kid burning the very last of their energy reserves just to maintain ho…

I also find the kids can be having a massive tantrum, kicking and screaming for ages, and then moments later they're sleeping like rocks.

[deleted]

Re: Little kids burn so much energy, they’re like a different species, study finds

#53

Post by tw04 »

hansvm wrote: post #26
tw04 wrote: post #11

Earlier quoted context omitted.

This seems almost unbelievable to me. Almost everyone I know, with a handful of exceptions I can think of, had a dramatic change in what I can only say was metabolism at 30 declining steeply to 40. I can tell you personally my ability to lose weight when exercising daily has decreased significantly since 30. If it’s not metabolism, then what? Diet and exercise are almost identical.

Without more details if be inclined to blame "almost identical" as the culprit (not an expert): Making all your meals 5% bigger would cause a weight gain of nearly 10lbs/yr, and the kind of switch in diet that can happen naturally with age (especially including eating out more with friends) can make it hard to spot incremental changes. Moreover, a lot of exercise doesn't actually do much for weight loss (it's still i…

Sure. I’ve got about 20lbs more muscle than I did at 30. I currently lift 3-4 times a week and run 3.5+ miles 5-6 times a week. At 30 I worked out or ran 3 days a week.

I eat out less now and generally pay attention to what I eat vs just eating whatever is in front of me. Nearly identical meaning proportions are the same but I eat less junk food now.

I was a college athlete, but there’s no way I carried the fitness forward ~6 years without maintaining my college level of workouts.

I realize it’s all anecdotal, but based on my personal experience, the study is really tough to take at face value.

Re: Little kids burn so much energy, they’re like a different species, study finds

#54

Post by [deleted] »

tw04 wrote: post #11
Supersam654 wrote: post #8

Personally, I was more surprised by the various groups of people who _don't_ have higher metabolic rates: > Children’s metabolic rates stay high until age 5, but the rate slowly begins to glide down until it plateaus around age 20. Interestingly, adult rates are stable until age 60, when they begin to decline. After age 90, humans use about 26% less energy daily, Pontzer says. > The study also found that pregnant wom…

This seems almost unbelievable to me. Almost everyone I know, with a handful of exceptions I can think of, had a dramatic change in what I can only say was metabolism at 30 declining steeply to 40. I can tell you personally my ability to lose weight when exercising daily has decreased significantly since 30. If it’s not metabolism, then what? Diet and exercise are almost identical.

[deleted]

Re: Little kids burn so much energy, they’re like a different species, study finds

#55

Post by jeffrallen »

edoceo wrote: post #21
InfiniteRand wrote: post #15

They're a different species and they are replacing us

Gotta make way for the homo-superior.

Otoh, if you watch 9 year old boys on the playground, you would conclude that Neanderthals walk among us. Jeesh.

Re: Little kids burn so much energy, they’re like a different species, study finds

#56

Post by riffraff »

hprotagonist wrote: post #6

> But children also burn out fast. This is well known in emergency medicine. Not only do kids burn out quick, they also burn out completely because they, unlike adults, don't keep a reserve. This applies to homeostasis, too. Consequently: young trauma victims that "look OK" need to be very closely attended to, because what you might be seeing is a kid burning the very last of their energy reserves just to maintain ho…

Oh man, I always thought my kid had shitty homeostasis but thought it boiled down to just having little mass, I never considered it might be an energy thing!

Re: Little kids burn so much energy, they’re like a different species, study finds

#57

Post by azeirah »

jjtheblunt wrote: post #39
rubyist5eva wrote: post #20

My 22 month old son wakes up at 5am, and doesn't stop running, climbing, singing and dancing, any possible "activity" you can think of until 7pm when we have to wrangle him for about an hour during "quiet time" until he eventually decides it's time him to sleep. The description "different species" seems apt because I really don't see how it's possible for such a tiny "human" to just have so much energy. All in jest o…

seems invariant across many mammals for toddlers at least: in dogs "the zoomies" for example fits the same description, cats too, unsure what else is comparable

Oh yeah, my two kittens (and any kittens for that matter) were notorious in this matter.

Play like nothing matters for half an hour, run, jump, sprint, crawl, scratch, everything like your life depends on it. And then just fall down on the spot for like an hour or two, followed up by a repeat of the same cycle.

It's cute to watch, but also kind of scary. They just look _empty_ after that intense a playtime.

Re: Little kids burn so much energy, they’re like a different species, study finds

#58

Post by IkmoIkmo »

tw04 wrote: post #11
Supersam654 wrote: post #8

Personally, I was more surprised by the various groups of people who _don't_ have higher metabolic rates: > Children’s metabolic rates stay high until age 5, but the rate slowly begins to glide down until it plateaus around age 20. Interestingly, adult rates are stable until age 60, when they begin to decline. After age 90, humans use about 26% less energy daily, Pontzer says. > The study also found that pregnant wom…

This seems almost unbelievable to me. Almost everyone I know, with a handful of exceptions I can think of, had a dramatic change in what I can only say was metabolism at 30 declining steeply to 40. I can tell you personally my ability to lose weight when exercising daily has decreased significantly since 30. If it’s not metabolism, then what? Diet and exercise are almost identical.

Not sure I noticed anything like this myself. I did see however, around 30, a massive change in work/life balance.

I went from a rather care-free person in my twenties, who took all vacation days he could, worked part-time for stints in junior functions, to becoming a manager and working 55 hour workweeks and less vacation. That tripled my disposable income and reduced my free time by a third.

My caloric intake before this had been somewhat restricted by these two factors: not enough money to have 'eating out multiple meals daily' be an affordable habit. And not limited enough in time to make that habit-of-convenience a necessary one.

Now I can both afford it and time-wise it helps not to have to prepare every single meal anymore. But for my caloric intake this new habit doesn't help.

We're not talking about massive changes here, but even a 5% increased daily intake stacked over the course of years adds up.

Not to mention changes in non-base metabolism caloric expense. Spending so much time on an office chair definitely leaves less time to move the body. Lots has changed about my behaviour. e.g. in my twenties I often spent two nights a month dancing from 1am till 5am, nowadays I'd still go out but it'd be more of a pub-setting, sitting & drinking.

So I do see changes, but I wouldn't necessarily relate them to base metabolism rates. In your case diet and exercise are almost identical but it definitely wasn't for me.

Re: Little kids burn so much energy, they’re like a different species, study finds

#59

Post by vidarh »

tw04 wrote: post #53
hansvm wrote: post #26

Earlier quoted context omitted.

Without more details if be inclined to blame "almost identical" as the culprit (not an expert): Making all your meals 5% bigger would cause a weight gain of nearly 10lbs/yr, and the kind of switch in diet that can happen naturally with age (especially including eating out more with friends) can make it hard to spot incremental changes. Moreover, a lot of exercise doesn't actually do much for weight loss (it's still i…

Sure. I’ve got about 20lbs more muscle than I did at 30. I currently lift 3-4 times a week and run 3.5+ miles 5-6 times a week. At 30 I worked out or ran 3 days a week. I eat out less now and generally pay attention to what I eat vs just eating whatever is in front of me. Nearly identical meaning proportions are the same but I eat less junk food now. I was a college athlete, but there’s no way I carried the fitness f…

People tend to massively overestimate how much the extra muscle mass matters, and how much they burn during exercise, though, and it takes very little to overcompensate with a little extra food here and there.

I lift too, and for many years I wrote down everything I wrote, and weighed myself every morning. I could tell very precisely how much I burnt, and it tended to shock people on lifting forums who were certain they needed to down lots protein shakes to get enough calories.

At my peak lifting I wasn't huge, but I was around qualification levels for competitive powerlifting for my weight class at the time (I squatted about 200kg, benched 150kg), and exercised 5 days a week.

I burned about 2000kcal/day on average. I tested that many times when bulking or slimming down by seeing how much I needed to increase it or drop it down. And it changed a little as I added muscle, but much less than you might think.

I'd have people arguing with me on fitness forums that there was no way I was burning that little, and that I really needed 3000kcal/day or more, and then complain about why they were adding weight.

People in a more active job would burn more than that, and people with a more active life outside of work and the gym as well, but people are notoriously bad at estimating their activity levels and apply calorie level assumptions that are often many decades out of date and based on far more labour intensive daily lives. Basically the only way you'll know is to track and measure.

Re: Little kids burn so much energy, they’re like a different species, study finds

#60

Post by Cyril_HN »

Synaesthesia wrote: post #48

This is why parents are always shouting at their kids to dress warmly, but I remember always being hot in my clothes as a kid and needing to take them off.

In summers I would bathe in cold water until I was blue and then some. My parents said that they used to be worried by it, but they realised I was totally OK. They would keep an eye on me, but if I was out of the bath, pool, or ocean for a couple of minutes I would be right back to warm.

All I remember as a kid is being unusually warm in almost any cold conditions. Even now the cold doesn't bother me much, certainly less than my peers.

I'm sure metabolism isn't everything there, but it probably helps.

Post reply on HN