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Daily energy expenditure through the human life course

research.brighton.ac.uk

201–210 of 256 posts

Re: Daily energy expenditure through the human life course

#201

I've always been curious about my own metabolism. When I was a teenaeger / in university I ate pretty badly. Chocolate bars every day after lunch, loads of carbs, not to mention alcohol, etc etc. I was rail thin. I once got a body fat assesment when I joined a gym (I did no exercise at all and this was a brief attempt to get buff) and the person doing the test was shocked and couldn't pinch anything to measure. I had…

I had a similar trajectory. The transition from one to the other was a long course of antibiotics.

Re: Daily energy expenditure through the human life course

#202

Earlier quoted context omitted.

No I legit ate way much much more in my 20s. I'm not misremembering. I ate more

>I'm not misremembering It's the easiest explanation. As a gym bro that regularly cycles weight, it's is remarkably easy over/under estimate intake just going off recollection. I always think I'm dialed in until I write things down (I'm almost always eating way fewer calories than I think).

Okay, so just to be clear: the OP is describing a phenomenon that is extremely widely reported, and is doing so in discussion thread about study that also reports finding this phenomenon, and your claim is that the simplest explanation is that OP is misremembering, and the research is just wrong?

Do you have any evidence for this bizarre dismissal?

Re: Daily energy expenditure through the human life course

#203
post #202

Earlier quoted context omitted.

>I'm not misremembering It's the easiest explanation. As a gym bro that regularly cycles weight, it's is remarkably easy over/under estimate intake just going off recollection. I always think I'm dialed in until I write things down (I'm almost always eating way fewer calories than I think).

Okay, so just to be clear: the OP is describing a phenomenon that is extremely widely reported, and is doing so in discussion thread about study that also reports finding this phenomenon , and your claim is that the simplest explanation is that OP is misremembering, and the research is just wrong? Do you have any evidence for this bizarre dismissal?

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 article states that the basal expenditure increases with "fat free mass", so someone fat but muscular will have this "overheating" problem even stronger?

Re: Daily energy expenditure through the human life course

#204

Earlier quoted context omitted.

No I legit ate way much much more in my 20s. I'm not misremembering. I ate more

I had to supplement with calorie shakes for workout guys in my 20's, just to maintain weight. I ate trash, and a shit load of it. And that's not considering the amazing levels of calories I would've consumed from alcohol. Same activity level now as then. But now if I think too hard about a candy bar I gain weight that never goes away.

> Same activity level now as then.

As you go from untrained to trained you burn less calories doing the same activity.

Re: Daily energy expenditure through the human life course

#205

Earlier quoted context omitted.

Humblebrag? Almost 100% of humans are incapable of doing a four hour 100km bike ride without a lot of prep and training. Nevermind doing this daily.

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?

Re: Daily energy expenditure through the human life course

#206
post #203
post #202

Earlier quoted context omitted.

Okay, so just to be clear: the OP is describing a phenomenon that is extremely widely reported, and is doing so in discussion thread about study that also reports finding this phenomenon , and your claim is that the simplest explanation is that OP is misremembering, and the research is just wrong? Do you have any evidence for this bizarre dismissal?

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.

Re: Daily energy expenditure through the human life course

#207

Earlier quoted context omitted.

Strava tells me I burned 3,3000 calories this morning on my (4 hour)100km bike ride. About the equivalent of drinking 2 cups of melted butter, or eating 50 pounds of lettuce. When I'm doing exercise like that regularly it's hard to eat enough.

Strava’s calorie estimation is awful. Depends on the elevation gains in your 100km ride but I think that 3,300kcal for a 100km/4h ride is generous. 800kcal/hr is hard work and keeping that up for 4h is even harder. 25kph does not sound like 800kcal/hr unless there was some reasonable elevation gains. I’d expect at least 1000m elevation gain over that 100km for those numbers to at least approach something sensible. If…

Yeah, 25km/h requires less than 150W [1], so it's 600Wh total, the efficiency of human metabolism is about 20% [2], so it's 3kWh of total energy input = 10.8MJ = 2600 kcal. (I have been using generous estimates, so this should be an upper bound)

[1] https://en.wikipedia.org/wiki/Bicycle_performance#Total_powe..., https://www.road-bike.co.uk/articles/cycling-power.php [2] https://www.quora.com/How-efficient-is-the-human-body-at-con...

Re: Daily energy expenditure through the human life course

#208

I've always been curious about my own metabolism. When I was a teenaeger / in university I ate pretty badly. Chocolate bars every day after lunch, loads of carbs, not to mention alcohol, etc etc. I was rail thin. I once got a body fat assesment when I joined a gym (I did no exercise at all and this was a brief attempt to get buff) and the person doing the test was shocked and couldn't pinch anything to measure. I had…

25 is about the age you’ve worked a year two after an undergrad. More money means more desk work and more access (speaking funds) to eat out

Re: Daily energy expenditure through the human life course

#209

Earlier quoted context omitted.

I wouldn’t be surprised if most thin people who claim to eat lots of junk food actually just eat a lot less regular food. In other words, they don’t eat many calories, but the calories they do eat are junk.

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

Re: Daily energy expenditure through the human life course

#210

Earlier quoted context omitted.

Muscle tissue burns 7-10 calories per pound per day. This means someone who gains 100 pounds of muscle (e.g. from 150 lbs untrained to a 250 lbs bodybuilder) would increase their metabolism by 700-1000 calories, almost a 50% increase in the average daily male calorie requirements of around 2000 calories.

Putting on 100 lbs of muscle is impossible without steroids for 99% of people even with 10-15 years of constant training. Estimates vary but 50 lbs of lean muscle mass is generally considered the natural maximum for men.

I think 100 was just a nice round number to make their point easier to read
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