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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)

#81

Post by throwaway22032 »

monero-xmr wrote: post #71
hn_throwaway_99 wrote: post #49

Earlier quoted context omitted.

It's not a mystery, but it also sort of pretends that humans are robots. That is, the human body has developed homeostatic mechanisms over billions of years, and a big part of that is that if your body thinks it's starving, it will try its hardest to (a) make you hungry so that you will do whatever you can to eat more, and (b) slow your metabolic rate so you don't die.

Yes you will be hungry but we are sentient beings who can ignore the urge to eat, just as we can control other base urges. You don’t see an attractive person and assault them, or someone with a desirable object and immediately steal from them. It’s called self control.

Agree with this. It's such a strange mindset to me.

I don't like getting up in the morning and going to work. I don't like selling things I no longer use. I don't like economising at the supermarket, and although I enjoy cooking sometimes, doing it all of the time just to survive gets quite tiresome. Etc.

Yet we just have to do those things, because we need money, we need to eat, etc.

Part of being a mature, successful adult is doing things that you might not immediately want to do.

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

#82

Post by mint2 »

alecst wrote: post #68
mint2 wrote: post #59

Earlier quoted context omitted.

Not this again: “Burning 600 calories with exercise means burning 600 fewer later.” No it doesn’t. That work is highly misinterpreted. Because it doesn’t ELI5 how body mass and composition and steady vs unsteady state actually play into it, people take away a meaningless self serving interpretation. If you start running 4-5 times a week, I guarantee you’ll be eating significantly more and burning significantly more.…

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 and focused on the personal story that went along with the hard facts and stats.

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

#83

Post by monero-xmr »

throwaway22032 wrote: post #81
monero-xmr wrote: post #71

Earlier quoted context omitted.

Yes you will be hungry but we are sentient beings who can ignore the urge to eat, just as we can control other base urges. You don’t see an attractive person and assault them, or someone with a desirable object and immediately steal from them. It’s called self control.

Agree with this. It's such a strange mindset to me. I don't like getting up in the morning and going to work. I don't like selling things I no longer use. I don't like economising at the supermarket, and although I enjoy cooking sometimes, doing it all of the time just to survive gets quite tiresome. Etc. Yet we just have to do those things, because we need money, we need to eat, etc. Part of being a mature, successf…

This website is such a fascinating place. Some of the most hyper logical and driven technologists on earth, who then wrap themselves in knots to explain away their lack of physical fitness, when the obvious solution is staring them in the face. People can’t bring themselves to hear the truth

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

#84

Post by mint2 »

Kirby64 wrote: post #73
mint2 wrote: post #59

Earlier quoted context omitted.

Not this again: “Burning 600 calories with exercise means burning 600 fewer later.” No it doesn’t. That work is highly misinterpreted. Because it doesn’t ELI5 how body mass and composition and steady vs unsteady state actually play into it, people take away a meaningless self serving interpretation. If you start running 4-5 times a week, I guarantee you’ll be eating significantly more and burning significantly more.…

I don’t think most people (besides some naive readings of that research) should come to that conclusion. The proper conclusion is that it will offset some of the calories burned by exercise through reduction in NEAT (non exercise activity thermogenesis), but not all of it. So a 600cal exercise may only have an effective net calorie addition of say, 400cal, due to reduction in NEAT. The problem becomes when people do…

The comment I replied to stated that was the conclusion - 600 burned meant 600 saved. So apparently the misinterpretation is common.

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

#85

Post by Jensson »

monero-xmr wrote: post #78
vl wrote: post #67

Earlier quoted context omitted.

The problem is that top-level competitive work takes a lot of mental and emotional effort. So even if I’m spending time on health, I can’t do it work 100% effort, and so result is still suboptimal.

I have trained myself to shut off work when I stop working. This took a lot of time. Very rarely nowadays is my sleep or time outside work disturbed by what is happening at work. It’s a meditative practice, but once you really get in the mindset of work being for work, family for family, sleep for sleep, etc. then you stop being bothered.

That means you probably aren't maximizing your career though, which was the point you have to make a choice there.

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

#86

Post by BeetleB »

monero-xmr wrote: post #36
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.

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.

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

#87

Post by sudosysgen »

paulpauper wrote: post #56
pitdicker wrote: post #43

Earlier quoted context omitted.

On average man burns ca. 2500 kcal per day, mostly in rest. One hour of reasonably intensive cardio burns 500~600 kcal. If you have two such workouts a week it comes down to an increased energy use of 2*600/(7*2500) = 7%. Or a large meal. Just looking at the numbers it seems spending some time at the gym is not going to do much for loosing weight. Or said differently: eating 7% less is easier. Of course cardio and st…

One hour of reasonably intensive cardio burns 500~600 kcal. If you have two such workouts a week it comes down to an increased energy use of 2 600/(7 2500) = 7%. Or a large meal. Just looking at the numbers it seems spending some time at the gym is not going to do much for loosing weight. Or said differently: eating 7% less is easier. Not sure about this. Herman Pontzer's work shows that the body adapts by burning fe…

That's just not possible. You aren't going to be burning less calories during sleep after a workout, you're going to be burning more due to increased protein synthesis as your body recovers (unless the workout was very light).

Reduced fidgeting leading to 600 calories less in a day is not reasonable, either.

To drive this home, just look at professional cyclists : a lot of them have to eat 5000+ calories a day, because they burn 3500+ calories just training, on average, for years and years.

Additionally, if you work out more, you will increase your fat-free mass significantly.

In any case, Pontzer's work never seems to claim you somehow compensate against activity expenditure, it's actually a very strong independent variable in the model of the linked study?

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

#88

Post by sudosysgen »

paulpauper wrote: post #69
alecst wrote: post #68

Earlier quoted context omitted.

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

My own experience matches closer to Potzner's work. I see some initial loss on the after exercising but the rebound is really fast. Perhaps if you keep it up everyday there can be some long-term weight loss but it will not be continuous, and if you stop the weight will come back fast.

Your weight is an equilibrium between calorie intake and caloric expenditure. Increased weight increases baseline expenditure, hence the equilibrium.

If you stop exercising, but keep the same caloric intake as before, yes, it will rebound really fast, because the equilibrium point will stay the same. If you want to move the equilibrium, you either need to do the exercise regularly forever, or reduce your caloric intake, or build significant amounts of muscle (fat free body mass) to increase your baseline. expenditure

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

#89

Post by sudosysgen »

331c8c71 wrote: post #45
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 problem with losing weight without exercising is that it's not only fat but also muscles that are lost.

That's very true, but if you have healthy hormone levels and so long as your body fat percentage is high, you will lose way more fat than muscle, even without exercise. In bariatric surgery patients, for example >70% of weight loss is fat on average, and for 2/3rds of patients in some study there is less than 15% loss in fat-free mass.

On the other hand, if you're a man, then going to a reasonable body fat percentage is likely to make it easier for you to gain muscle.

So, as long as you make sure to eat a lot of protein, unless you have a large caloric deficit, you can expect muscle loss to be minimal (studies show that for extended moderate caloric deficits, muscle protein synthesis doesn't really decrease)

So yes, but if you're overweight, it's still a very good change on the balance, and you'll be way more fit in the end even if you do lose a bit of muscle.

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

#90

Post by jrs235 »

Zambyte wrote: post #19
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…

In a sense I am thankful I graduated into the covid lockdowns. It made this dramatic change obvious to me, and I made a similarly dramatic change in my diet. I went from literally having a buffet every meal in college to having a cup of coffee for breakfast, and what I would consider a normal sized meal for dinner. I realized after about 2 years of this that I was borderline under-weight, so I decided to start eating…

I eat when I'm hungry, not when a clock says I should.

Edit: My family doesn't understand why I haven't gotten the family beer belly most males in my family and extended family have.

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