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Daily energy expenditure through the human life course

research.brighton.ac.uk

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Re: Daily energy expenditure through the human life course

#231

Post by Jenda_ »

layla5alive wrote: post #221
naijaboiler wrote: post #216

Earlier quoted context omitted.

one possible explanation for me, calories ingested != caloric intake. I ate more, pooped more. So even if my body's metabolic efficiency didn't change, perhaps my ability to extract calories from what i ate changed. Sitting down and eating 6 plates of pasta at Fazolis all-you-can-eat for $4 (or $6) + 12 breadsticks every wednesday evening, is not something you can misremember. i was a broke student, and it was most e…

I believe you, naijaboiler. Posts like Jenda's are depressingly unimaginative. I wish HNers, and people in general, would learn some biology, and use some critical thinking to imagine that when something doesn't fit their very basic mental model, that's probably because there's exponentially more to know/learn(!). Maybe then they would stop thoughtlessly regurgitating such basic misconceptions. Biology has so much co…

> Posts like Jenda's are depressingly unimaginative. I wish HNers, and people in general, would learn some biology, and use some critical thinking to imagine that when something doesn't fit their very basic mental model, that's probably because there's exponentially more to know/learn(!).

That's why I was not disputing the premise (like previous commenters did), but asking for possible explanations!

Re: Daily energy expenditure through the human life course

#232

Post by lm28469 »

m3kw9 wrote: post #52
logicchains wrote: post #34

Muscle burns more energy than fat. As people age, their muscle mass declines without sufficient exercise, so we'd naturally expect the average person's metabolism to decline via this even if "metabolism per kg muscle" didn't change.

A lot of skinny people have high metabolism, how do you explain that?

I have two friends like that, both were diagnosed with thyroid issues

So to answer you question, hormones

Re: Daily energy expenditure through the human life course

#233

Post by _Algernon_ »

glouwbug wrote: post #209
_Algernon_ wrote: post #141

Earlier quoted context omitted.

This. Plenty of times I've been to lazy to make dinner and ate 200g of chocolate and a coke in a single sitting.

The American dream

I believe for this to be the American dream, you have to do this in addition to dinner.

Re: Daily energy expenditure through the human life course

#234

Post by layla5alive »

Jenda_ wrote: post #231
layla5alive wrote: post #221

Earlier quoted context omitted.

I believe you, naijaboiler. Posts like Jenda's are depressingly unimaginative. I wish HNers, and people in general, would learn some biology, and use some critical thinking to imagine that when something doesn't fit their very basic mental model, that's probably because there's exponentially more to know/learn(!). Maybe then they would stop thoughtlessly regurgitating such basic misconceptions. Biology has so much co…

> Posts like Jenda's are depressingly unimaginative. I wish HNers, and people in general, would learn some biology, and use some critical thinking to imagine that when something doesn't fit their very basic mental model, that's probably because there's exponentially more to know/learn(!). That's why I was not disputing the premise (like previous commenters did), but asking for possible explanations!

I apologize, you're right - you were sincerely questioning "where does the energy go?" - which is laudible. I mistakenly read your post as insincere and lumped you in with the others who were being dismissive. I should have directed my criticism at grandparent posters.

There's definitely a heat-loss phenomenon - look for skinny kids in shorts in 40 degree weather - but it's also the case that a variable amount of input calories can be discarded without full digestion by the body - energy not even extracted for use. The religiously calories in : calories out folks assume a linear digestion efficiency relationship between total calories consumed and that this holds unifomally across the population. Given the complexity of biology, they should be unsurprised that there will be myriad outliers

Re: Daily energy expenditure through the human life course

#235

Post by layla5alive »

lkbm wrote: post #206
Jenda_ wrote: post #203

Earlier quoted context omitted.

I don't understand where does the excess basal energy expenditure go. Do persons like the OP when <25 y.o. produce significantly more heat (e.g. wearing only t-shirt and shorts even in winter, and "dying" in the summer)? Does the skinnier body mean way bigger heat losses, even when compared to bigger surface area after getting fat (i.e., way higher surface temperature)? (presumably yes, but to this extent?) The artic…

Skinnier would mean more surface area to volume, but less surface area total. If we're just looking at energy in and energy out, it could partly be less thorough digestion. I wonder if there are poop studies that find more leftover fat or carbs in faeces of children.

Yes - for example: overconsume fat to an extreme degree and watch the color of your stool turn towards white/clay, and watch it start to float, among other notable changes (size, shape, consistency, odor, etc.)

Re: Daily energy expenditure through the human life course

#236

Post by blipvert »

nradov wrote: post #228
blipvert wrote: post #223

Earlier quoted context omitted.

It’s what Strava says I’m burning so I can only go by that. 750 would still be above the low end of the range quoted by the OP. The amount of extra food I needed to start eating!

You shouldn't go by Strava numbers, they are known to overestimate.

Fair enough but it’s still going to be at the low end of the range 700-1000 range given earlier for 100lbs of muscle gain.

I’m ~75kg. Schwarzenegger was ~120kg in his prime. 45kg difference is (2.2lbs to the kg) 100lbs (differences between UK and USA imperial notwithstanding).

The chances of me going from where I am to a AS physique is zero!

Re: Daily energy expenditure through the human life course

#237

Post by naijaboiler »

layla5alive wrote: post #234
Jenda_ wrote: post #231

Earlier quoted context omitted.

> Posts like Jenda's are depressingly unimaginative. I wish HNers, and people in general, would learn some biology, and use some critical thinking to imagine that when something doesn't fit their very basic mental model, that's probably because there's exponentially more to know/learn(!). That's why I was not disputing the premise (like previous commenters did), but asking for possible explanations!

I apologize, you're right - you were sincerely questioning "where does the energy go?" - which is laudible. I mistakenly read your post as insincere and lumped you in with the others who were being dismissive. I should have directed my criticism at grandparent posters. There's definitely a heat-loss phenomenon - look for skinny kids in shorts in 40 degree weather - but it's also the case that a variable amount of inp…

this. Yes the physics of weight is ridiculously straight forward. Its first law of thermo (calories in = calories out). The biology is incredibly complex and that's before we get to the pyschological, to the point of making CICO too overly simplistic to describe actual practical reality. The body is not some perfect energy converting mechanical machine.

People also forget "metabolism doesn't change with age" narrative is a based on a paper that used population-wide statistical model. That approach measures "average treatment effect" and is directionally useful in general but incredibly unhelpful in addressing individual differences and nuances. Something is true on average does not mean it is true "for every" or even "for any"

Re: Daily energy expenditure through the human life course

#238

Post by 0xfaded »

Jenda_ wrote: post #205
0xfaded wrote: post #176

Earlier quoted context omitted.

When I lived in Denmark I was riding 2x 5km to and from work. I then needed to start going somewhere ~80km away, and I was able to do it without special preparation. After a couple of times I was able to do it both ways in a day. Now I live in America need a car :(

I also did a 65km and then 135km ride with similar "training" (2x7km four times a week to school), but it was way slower than 25km/h. They took 4.5 and 10 hours, respectively. I think riding 100km without training is possible, but at 25km/h very difficult. > Now I live in America need a car :( Why? Are there even longer distances?

No, there's just no cycling infrastructure.

I was doing it on a roadbike and could comfortably average 27km which got me there 3h. Driving was about 1.2h.

In the summer, I would start pedalling at 5am and get to a local cafe at 8. The first hour was amazing, broad daylight and you basically had the whole road network to myself.

Re: Daily energy expenditure through the human life course

#239

Post by Jenda_ »

0xfaded wrote: post #238
Jenda_ wrote: post #205

Earlier quoted context omitted.

I also did a 65km and then 135km ride with similar "training" (2x7km four times a week to school), but it was way slower than 25km/h. They took 4.5 and 10 hours, respectively. I think riding 100km without training is possible, but at 25km/h very difficult. > Now I live in America need a car :( Why? Are there even longer distances?

No, there's just no cycling infrastructure. I was doing it on a roadbike and could comfortably average 27km which got me there 3h. Driving was about 1.2h. In the summer, I would start pedalling at 5am and get to a local cafe at 8. The first hour was amazing, broad daylight and you basically had the whole road network to myself.

There is almost none here (around Prague, .cz) too. I ride on the roads.

Yeah, unfortunately, for me, even after some training, it's still hard for me to average over 22 km/h (entire travel including stops; the moving average is about 25km/h, e.g. https://www.strava.com/activities/9688833121).

Re: Daily energy expenditure through the human life course

#240

Post by tuatoru »

eastbound wrote: post #222
ashconnor wrote: post #217

Earlier quoted context omitted.

I was rake thin until I started lifting weights with a buddy of mine at university. However it wasn't until I started GOMAD that I noticed any muscle and weight gain. Before that I was eating crap. Lots of things that I that were high in calories but not enough of them throughout the day to exceed my metabolism or get close to the amount of protein I needed. I think if you could go back in time and count the calories…

Maybe lifting weights => Body actually uses and stores all food => Fat at 40? Whereas a thin man who doesn’t do sports never gets really fat?

N=1, but visceral fat starts building up sometime after age 40 anyway. About 52, in my case.
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