Reading this article I'm a little confused by the author's conflation of brain energy and the energy expenditure of the body as a whole. In the beginning they mention:
> "Your brain consumes roughly 20 to 25% of your body's total energy at rest"
while later they say:
> "Even chess grandmasters, who sit for hours in states of intense concentration, burn only about 1.67 calories per minute while playing, compared to 1.53 calories per minute at rest"
That second figure seems to refer to whole-body expenditure, not just the brain. And intense cognitive work doesn't happen in a metabolic vacuum - there's increased cerebral blood flow, elevated sympathetic nervous system activity, changes in heart rate variability, hormonal shifts (cortisol, adrenaline). These all have systemic metabolic costs that go beyond the glucose the neurons themselves consume. So the "it's just a banana and a half" framing might be undercounting by quietly switching between brain-only and whole-body measurements.
Also somewhat related - the link to businessinsider about chess grandmasters is broken, but another very interesting rabbit hole here is how energy expenditure is actually measured. A lot of what consumer devices and even many studies report is based on proxy biomarkers like heart rate, HRV, weight, age, and sex, run through linear regression models. True calorimetry (indirect via gas exchange, or direct in a metabolic chamber) is expensive and impractical outside lab settings. That means the precise calorie figures cited with such confidence - the "100 to 200 extra calories" from a day of thinking, or the per-minute burn rates of chess grandmasters - likely carry wider error bars than the article suggests. We don't really have a great way to measure real-world energy expenditure accurately at the individual level, which makes me a bit cautious about the neat narrative of "thinking is calorically cheap, full stop."
That said, the core point about adenosine accumulation and perceived exertion affecting training quality is fascinating and well-supported — that part of the article is genuinely useful regardless of the calorie accounting.
Can you expand on that please? Because I can tell you as a matter of fact that when I go for a run for an hour I burn well over 800 calories.
Sure - how did you arrive at the 800 kcal figure? Most likely a wearable or an app, and those estimates are based on rough linear regressions from weight, age, sex, and heart rate - not actual calorimetry. The error margins on those numbers are significant, but the devices present them with false precision that makes people treat them as ground truth.
Even setting accuracy aside, the framing is the issue. Your basal metabolic rate - just keeping your organs running, blood circulating, cells maintained - accounts for 60-70% of your total daily energy expenditure. Add the thermic effect of food (~10%) and you're at roughly 70-80% of your energy budget spent before you even lace up your shoes [1]. Exercise typically makes up the remaining 20-30%. So that hour of running, while genuinely beneficial for a hundred other reasons, is a relatively small slice of your total daily burn. And not all calories are equal on the intake side either - your body spends 20-30% of the energy in protein just to digest it, compared to 0-5% for fat, so "800 kcal burned = 800 kcal of anything eaten" doesn't hold up.
That's what I mean by "myth" - not that exercise burns zero calories, but that the popular mental model of "I ran for an hour so I earned X calories of food" is built on inaccurate measurements, treats all calories as interchangeable, and overweights exercise relative to what your body spends just existing. Curious though - do you track your intake with the same rigour, and if so, do you find the numbers actually add up in practice?
[1]: https://my.clevelandclinic.org/health/body/basal-metabolic-r...
I don't have the background to fully evaluate how true that is. I read "Burn" by Herman Pontzer, which at least makes a very good case for it.
So if you view this from a time use perspective, just skipping that sandwich is way better than running for an hour. And many people can't spare an hour a day just to make up for a sandwich. Hence - "not a lot" - Its too expensive time-wise for the caloric balance effect it provides. Just skip the sandwich instead.
Depends on your level of exercise. I often cycle 100km per day and can tell you if I ate only the 2000 kcal I hypothetically need I would go into a strong deficit.
Right, and that's kind of my point - the "2000 kcal" figure is itself part of the problem. It's a rough global average that doesn't account for your sex, age, weight, body composition, activity level, or even climate. It's a number on a food label, not a physiological reality for any specific person.
And even if you could nail down your actual total daily energy expenditure, calorie counting treats all calories as equal, which they aren't. Your body spends 20-30% of the energy in protein just to digest and metabolize it, compared to 5-10% for carbohydrates and 0-5% for fat. So 100 kcal of chicken breast and 100 kcal of butter are not metabolically equivalent - your body nets significantly less usable energy from the protein. This is the thermic effect of food, and it alone accounts for roughly 10% of your total daily energy expenditure.
Speaking of which - basal metabolic rate (just keeping your organs running, blood circulating, cells maintained) accounts for about 60-70% of total daily energy expenditure. Add the thermic effect of food on top and you're at roughly 70-80% of your energy budget spent before you even stand up from bed [1]. Physical activity - including your 100km rides - typically makes up the remaining 20-30%, though obviously that range is wide and shifts dramatically for endurance athletes.
So yes, of course people who cycle 100km need more fuel. Nobody is disputing that. My point is that most people vastly overestimate how many calories exercise burns relative to what their body spends just existing, and they use kcal as a universal unit of nutritional value when the body's actual energy extraction varies significantly by macronutrient composition. People optimizing purely on calorie numbers are working with a model that's far rougher than they think.
And this whole picture gets worse with wearables pushing calorie counts front and center. You see it all the time - "my wearable shows that i burned 300 kcal with that activity so it zero outs that sweet thing I ate earlier that was also 300 kcal" That's wrong on multiple levels - the device estimate is inaccurate to begin with, the thermic processing of that pastry isn't equivalent to the "300 kcal" on its label, and your body doesn't do neat arithmetic like that anyway. But with every fitness app and smartwatch plastering a big kcal number on your workout summary, it's becoming the default way people think about food and exercise, and it's reinforcing exactly the wrong mental model.
[1]: https://my.clevelandclinic.org/health/body/basal-metabolic-r...
Many people tell me I need to lift weights to lose weight.
On mornings when I actually put in real effort, I pay for it with a significant cognitive performance penalty for the remainder of the day. I want to do nothing more than sleep an hour after a workout, which is bad timing, because that's when I need to clock into work.
I stay hydrated, get enough sleep, etc. People tell me that I'm over training, which is ridiculous, because anything less would be easy and contravene the purpose of the workout.
This is why I prefer to exercise in the evening, but there are known negative effects [0] of physical exertion on sleep quality.
If I actually did all the exercise I needed to do at the gym in the morning, then I'd probably have to sleep at 9:00 PM and wake up at 4:00 AM. There's no room to live in that schedule.
Training light is a great way of winding up doing a whole lot of nothing.
Give time to ramp-up. I like to start 2-3 days with things like the "7 minute workout" before dive in into anything more complicated.
Is better quantity than "quality" until you actually can put the discipline and consistency. If not, just walk is good enough
If you're exercising to lose weight, you're probably thinking that more exercise means more weight loss, which means that you could be overtraining.
I recently got a second Apple Watch to wear to bed to track my sleep, and it's given me some really great insights into when I'm hitting the red zone and need to dial back training. For exercise, more intensity is not always better. What matters is consistency, not consistently high intensity.
No you dont. Exercise does help, and has many other benefits but is not the main driving factor for losing weight. Diet is by far the most important one. Calories intake vs expenditure is the only thing you need to worry about if your primary goal is weight loss.
This doesn't mean you aren't over training.
If it's strength training... Without knowing the specifics what you are describing sounds like too much volume (and training for hypertrophy). Lower reps (3-5) & higher weight will have more of a strength stimulus and be less taxing.
If it's cardio... you probably should be at a lower intensity and going for longer.
Exercise a little earlier in the evening?
This is stupid. All you need to do is to get used to being hungry to the point of losing 0.1kg/day and measure yourself a lot (I'm doing the same).
Actually for me working out increases my appetite, and I feel like I have to eat so thar the gym session doesn't go wasted.
The website owner didn't even bother to check for hallucinated links, though https://journals.physiology.org/doi/full/10.1152/japplphysio... does exist and somewhat backs up the clickbait headline, so it would be satisfying comeuppance if the mods could just replace the submission accordingly.
Granted, you don't like to like this style of writing, I don't either. But you don't have to auto-accuse AI writing either. Also, there's nothing wrong with using AI to rephrase a manually written text for better readability, plenty of people use AI for that too rather than writing the entire thing.
I'm worrying that soon, I will have to hunt for non-AI essays by them just being worse written/more 'crude' and not as eloquently written as an AI would do :-/ Basically, seeking out "authentic human slop".
For the record, an AI detector that appears to have put work into reliability and that I trust very much from my own testing, Pangram (https://www.pangram.com), says this is 100% AI generated. I've used it plenty before when experimenting with AI-collab writing, both fiction and non-fiction, and it's frustratingly accurate in identifying what is and isn't my contribution. I have since largely given up trying to do AI-collab writing, because no matter how nice the writing looks in the moment, it always reeks when read closely, or on later days.
(Also have a look at Wikipedia how to identify signs of ai writing.)
> Here's the part that surprised me:
Might as well have said "here's the kicker" and used emojis instead of bullets. Maybe you can share your reading sites as you seem rather undrrexposed to not recognize this immediately lol.
Edit: I mean come on man, how can you not tell?! I'm still cringing from this one:
> The incremental cost of actually thinking hard? Almost nothing.
Edit II
"This isn't one study"
Dum dum dum. Sooo dramatic. 100% slop.
I asked "Can you give me a short essay on the history of fire." Maybe the type of writing requested has a massive effect on the language used?
"Here is one paragraph of an idea, an abstract of a report. Write a blog post."
Whereas a "history of fire" contains no article in the prompt and so might have more material from its own auto complete database to draw from.
Even once is rare unless I've been out drinking for the night.
I can see why every vegetarian should take it. But if you eat meat regularly, your creatine stores will be at a level where you'd probably only see a cognitive benefit at times of sleep deprivation. But if you're regularly sleep-deprived, then you'd do best by addressing your sleep issues.
Most of the computation and learning that occurs is attributable to the relative timing of spiking events. A lot of information can be encoded in the delay between 2 spikes. The advantage of biology is that there is no explicit quantization of the time domain that must occur. Biology gets to do a lot of things "for free". Simulating causality in a computer in a similar way requires a priority queue and runs like ass by comparison.
We end up using 100W (2000kcal/day) for the whole body, or about 20W for the nervous system alone (though a nervous system alone wouldn't be able to survive). That's comparable to what a modern laptop uses. Sure, that laptop can't run a large LLM at any reasonable speed, but it can do basic math far better than my brain. By a comically large margin. Just a consequence of the very different architectures chosen
"Artificial neuron" was a useful metaphor at the beginning, but they really are a very simplified model based on what some people understood of neurology back then. They are not that useful to get insights into how actual neurons work.
I know the metaphor isn't exact, it's just how i thought of it.
The big copy on the front page says:
> Your Apple Watch *tracks* VO2 Max—one...
While you have to read through FAQ where you see:
> The watch *estimates* your cardio fitness during outdoor activities and stores it in Apple Health, which our app reads automatically.
All emphasis are mine.
I think it's a little disingenuous to sell this as "Your VO2 Max, finally visible" when it's actually just an estimate from a watch, based on biomarkers. When the real VO2 is measured in a lab with a more involved equipment.
A 2025 validation study involving 30 participants found that Apple Watch underestimated VO2 max by a mean of 6.07 mL/kg/min (95% CI 3.77–8.38) when compared to indirect calorimetry, the gold standard method. The mean absolute percentage error (MAPE) was 13.31%, and the limits of agreement showed considerable variability ranging from -6.11 to 18.26 mL/kg/min [1]. Another 2024 study found similar results, with the Apple Watch Series 7 showing a MAPE of 15.79% and poor reliability (ICC = 0.47) [2].
[1]: https://journals.plos.org/plosone/article?id=10.1371%2Fjourn...
You don't suffer from a lack of time, but rather a lack of energy. And actually, you don't suffer from a lack of energy, but a lack of activation energy.
We colloquially refer to activation energy as motivation. But maybe that's not the whole story. Some of it is willpower and personality, but maybe some of it is a buildup of adenosine.
This squares with my personal experience. It's harder to start things after day's worth of intense mental effort.
https://www.science.org/content/article/mentally-exhausted-s...
Willpower is limited. Hard workout means intense cognitive effort is much harder to pull off.
It takes at least a week until it gets stored in the brain if you start taking it.
For me as N=1, training after thinking is easier than the reverse.
Found myself practically stop longing for sweets during programming; have more energy during workouts (135 KG bench press and all the other stuff).
5 g daily is what considered to saturate your muscles.
Some report that any additional helps cognitive tasks (but I haven’t seen definitive studies besides the sleep deprivation).
I take 7.5 g
They list a study and more info on that page. Probably why almost all pre-workouts include caffeine. Some push for 300mg per serving.
Yohimbe gives some weird heart effects also.
