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It's not your age that's slowing your metabolism, new research says (2021)

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Re: It's not your age that's slowing your metabolism, new research says (2021)

#91

Post by alecst »

mint2 wrote: post #82
alecst wrote: post #68

Earlier quoted context omitted.

So is your rebuttal to Pontzer et al that it doesn’t match your personal experience?

So we’re focusing on the anecdotal part to ignore the part where I point out the naive reading of his conjecture literally defies thermodynamics? I pointed out it’s literally impossible for it to work for a subset of the population. Over a hundred thousand endurance athletes in just the USA would have to literally defy the laws of thermodynamics for the naive reading to work. I can see why the question ignored that a…

Pontzer's work isn't about napping. It's about your body having a set point for how many calories it burns, independent (up to a factor of +/- a few hundred calories) of how much exercise you do. For most people this is true, as their work shows. It may not be true for extreme athletes. I don't think Pontzer's team of dozens of people working over ten years misunderstood basic thermodynamics. Their work clearly points to "compensation" -- the body making up for energy it burned during the day by gently lowering the metabolism later on.

Saying "burning 600 calories now means burning 600 less later" gets the point across. It's pretty much on the money for some people. For others compensation may not be total. I guess I'm not really sure where your beef is.

Re: It's not your age that's slowing your metabolism, new research says (2021)

#92

Post by lotsoweiners »

8f2ab37a-ed6c wrote: post #7

You see this often with middle class city people in their late 20s and 30s. You go from being athletic in high school and walking all day in college to suddenly being in your prime dating age, regularly out eating and drinking with friends or dates, hitting 2-3 cocktails a few nights a week. You start investing more into your ultra-sedentary career, which you drive to, which constantly requires more of your time to g…

Your version is a little low on the drinking calories in my opinion. I was skinny as a rail until my wife and I got together when I was 23 and started going to reverse happy hour at TGIFridays, Applebees, etc pretty much every night. Add drinking roughly another six pack most nights after the reverse happy hour along with smoking weed + more munchies and I never had a chance no matter how much exercise I did. I probably put on around 30-40 lbs in my first year of that lifestyle.

Re: It's not your age that's slowing your metabolism, new research says (2021)

#93

Post by lotsoweiners »

mint2 wrote: post #62
paulpauper wrote: post #14

Earlier quoted context omitted.

I don't think it's a s simple as inactivity. IF this were true, then being active would reverse the weight gains, but it does not, at least not for me and others. I was still as active in my 30s as I was in my late teens and 20s but still gained weight. Likewise, gyms are full of people in their 30s and 40s who are not losing weight despite regular attendance. Despite the popularity of fitness apps, people keep getti…

2 to 3 hours in a gym, (especially casual weights) does not even come close to scratching the surface of all the reduced activity that comes with office jobs, commutes and screen oriented amusement.

2-3 hours how often?

Re: It's not your age that's slowing your metabolism, new research says (2021)

#94

Post by yunwal »

WalterBright wrote: post #50
monero-xmr wrote: post #36

Earlier quoted context omitted.

If you want to reduce weight, then lower your caloric intake. You don’t even need to workout. Just measure your calories and keep decreasing them until the weight falls off. If you want to add in exercise, that’s great too, and then you can eat more calories. But if you studiously count calories and reduce them, you will lose weight - it’s guaranteed. If I put you on a desert island and starved you, you would lose we…

The most productive way to lose weight is to cut out the soda, juice, cookies, ice cream, donuts, Captain Crunch, pie, cake, candy bars, pastries, etc. Not the easiest thing to do, I know.

This list is missing alcohol

Re: It's not your age that's slowing your metabolism, new research says (2021)

#95

Post by Rury »

BeetleB wrote: post #15

This is from 2021 and was widely reported at the time. I see a lot of know-it-all comments, but the reality is they do not yet know why people gain weight in their middle age. No - the data doesn't show that it's merely due to being sedentary or changing diets.

Evidence suggests it's because lipid turnover decreases with age: https://www.sciencedaily.com/releases/2019/09/190909193211.h...

Re: It's not your age that's slowing your metabolism, new research says (2021)

#96

Post by mint2 »

alecst wrote: post #91
mint2 wrote: post #82

Earlier quoted context omitted.

So we’re focusing on the anecdotal part to ignore the part where I point out the naive reading of his conjecture literally defies thermodynamics? I pointed out it’s literally impossible for it to work for a subset of the population. Over a hundred thousand endurance athletes in just the USA would have to literally defy the laws of thermodynamics for the naive reading to work. I can see why the question ignored that a…

Pontzer's work isn't about napping. It's about your body having a set point for how many calories it burns, independent (up to a factor of +/- a few hundred calories) of how much exercise you do. For most people this is true, as their work shows. It may not be true for extreme athletes. I don't think Pontzer's team of dozens of people working over ten years misunderstood basic thermodynamics. Their work clearly point…

For hundreds of thousands of people it’s not true. That is not an exaggeration in numbers.

Handwaving away large numbers data points that disprove a theory is not how science is supposed to work.

And as we have seen in this thread, the lack of clarity on the nuance discourages people from making exercise.

Over simplifying it to 600 burned, 600 saved later is harmful and also inaccurate. (and yes More inaccurate than my loose choice of saying nap which you pointed out that led you to the wrong conclusions on my understanding, please consistently apply that critical standard)

Re: It's not your age that's slowing your metabolism, new research says (2021)

#97

Post by nradov »

BeetleB wrote: post #86
monero-xmr wrote: post #36

Earlier quoted context omitted.

If you want to reduce weight, then lower your caloric intake. You don’t even need to workout. Just measure your calories and keep decreasing them until the weight falls off. If you want to add in exercise, that’s great too, and then you can eat more calories. But if you studiously count calories and reduce them, you will lose weight - it’s guaranteed. If I put you on a desert island and starved you, you would lose we…

The mystery isn't how to lose weight but why weight increases despite no change in activity and diet.

But it doesn't. Weight only increases if energy input exceeds output. People lie about how much they eat.

Re: It's not your age that's slowing your metabolism, new research says (2021)

#98

Post by thefz »

nradov wrote: post #61
thefz wrote: post #46

Earlier quoted context omitted.

Mostly bullshit as fat is the primary source for energy in the body and hard to earn protein are not. It's a myth mostly, do fast, do exercise, you will not lose muscle.

Fat is only the primary energy source at lower output levels. As power output increases, metabolism shifts increasingly away from fat and towards glycogen. The shape of that curve is different for everyone, but ironically the people who most need to lose fat typically have the least ability to metabolize fat (not fat adapted) and so with any exercise they're mostly running on carbs. Once the glycogen stores run low t…

So you are proving wrong the reply that I prove wrong.

Ah, this site sometimes.

Re: It's not your age that's slowing your metabolism, new research says (2021)

#99

Post by rojeee »

mint2 wrote: post #96
alecst wrote: post #91

Earlier quoted context omitted.

Pontzer's work isn't about napping. It's about your body having a set point for how many calories it burns, independent (up to a factor of +/- a few hundred calories) of how much exercise you do. For most people this is true, as their work shows. It may not be true for extreme athletes. I don't think Pontzer's team of dozens of people working over ten years misunderstood basic thermodynamics. Their work clearly point…

For hundreds of thousands of people it’s not true. That is not an exaggeration in numbers. Handwaving away large numbers data points that disprove a theory is not how science is supposed to work. And as we have seen in this thread, the lack of clarity on the nuance discourages people from making exercise. Over simplifying it to 600 burned, 600 saved later is harmful and also inaccurate. (and yes More inaccurate than…

Also an endurance runner and read Pontzer's book. I do enough running for my wife to get pissed off! I agree with you that there's definitely more work which needs doing to understand metabolism in the context of endurance athletes. I don't think his work is outright nonsense though. Here's something to think about...

I ran 21 km yesterday, in zone 2, in a fairly glycogen depleted state. That was about 4:30min/km for 21km, with 600m of elevation - about 1500kcal of energy. I didn't eat or drink anything throughout the run. I'm a big nerd, so I took a lactate sample at the end. I didn't hit the first ventilatory threshold for the whole run and that indicates I'm burning a large proportion of fat compared to a normal person (and probably a normal recreational runner).

Afterwards, I ate a banana and had a couple of spoons of peanut butter + honey. A few 100kcal. Fast forward to the evening. I didn't eat any more than I usually would do if I had a few days off running. I went on with my day as normal and recovered fine the next day. I didn't feel hungrier than usual. Fairly standard. My body is well adapted to this kind of exertion. I think my body is quite efficient at doing every day things. I don't get out of breath walking up stairs, for example. Maybe it's fair to say I'm more energy efficient than a regular person. Perhps, I don't need to eat any more than usual immediately after running because I'm burning a high proportion of fat and my metabolism is quite efficeint anyway.

Someone who has a poor aerobic system wouldn't be capable of doing that. They'd likely be running at a much higher heart rate and bonk after 10km having not eaten any carbs the day before. They'd also likely need to eat a huge bowl of pasta afterwards just to feel OK. I suspect this person would feel like crap for the rest of the day (maybe even multiple days... Imagine.. they've likely just done a 10km at VO2max untrained) and I could completely imagine them having a nap or watching TV for the rest of the day as they'd have no energy to do anything else. Their bodies are not adapted to this kind of exertion. They are not efficient. Their body needs to rest to get back in equilibrium.

The energy requirement is the same in both cases but it comes from a different source. In my case the high fat oxidation is acting as a battery/buffer. In the average person, those fat stores are not really accessible when doing anything more than sitting or light walking. Both examples are in equilibrium but present in different ways.

Re: It's not your age that's slowing your metabolism, new research says (2021)

#100

Post by alecst »

mint2 wrote: post #96
alecst wrote: post #91

Earlier quoted context omitted.

Pontzer's work isn't about napping. It's about your body having a set point for how many calories it burns, independent (up to a factor of +/- a few hundred calories) of how much exercise you do. For most people this is true, as their work shows. It may not be true for extreme athletes. I don't think Pontzer's team of dozens of people working over ten years misunderstood basic thermodynamics. Their work clearly point…

For hundreds of thousands of people it’s not true. That is not an exaggeration in numbers. Handwaving away large numbers data points that disprove a theory is not how science is supposed to work. And as we have seen in this thread, the lack of clarity on the nuance discourages people from making exercise. Over simplifying it to 600 burned, 600 saved later is harmful and also inaccurate. (and yes More inaccurate than…

What is your interpretation of Pontzer’s data, then?
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