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At the risk of sounding to newage-y, I experience the benefits of exercising as energy balancing.

Solving problems, learning and building new things all day can be very mentally exhausting. Cardio, sports, lifting; helps re-balance the physical with the mental. I am sure there are more scientific words and biological descriptions that I lack the vocabulary for. If I get too mentally focused on a project/job/problem and go days without matching it with vigorous physical activity, I end up not sleeping as well, am less tolerant, more scattered and brain fog tends to start rolling in. If I counter it with the physical exercise or physical energy expenditure the mental clarity comes back, I sleep better, and don't have hair-triggered verbal impulse control issues. Otherwise, if I let it go for too long, lethargy sets in - which I attribute to the body/physical and mind/mental trying to rebalance itself. I dont think it cares that it makes me feel like crap overall, more that it's neutral in just wanting a balance however that comes about.

I often refer to exercise as me taking care of my mental health - as opposed to being physically fit. That could be seen as "exercise [being] the best cognitive exercise". Looking at it that way, exercise creates a mental-out imbalance, which causes the stored energy in the mind to be stimulated and need more output creating the mental sharpness. Obviously I have nothing to back up the claims other than decades of experiencing this to be true for me time and time again; though I do believe there are better biological explanations than energy.

> I often refer to exercise as me taking care of my mental health - as opposed to being physically fit.

Same. I don't care about my physical health all that much but my friends/family think i am some sort of health fanatic. It is the only thing that has gotten me through tough times, its my escape.

When I was most stressed and semi-burned out during my career I found that martial arts was the best way to decompress.

I especially preferred the kinds that heavily relied on sparring with partners during the class. It's _really_ hard to ruminate on everything you didn't get done today when the person opposite you will punch/kick you if your concentration falters =)

It's similarly hard to start overthinking when you're too tired to think, HIIT-style circuit training in a group worked pretty well.

Nowadays I'm a bit less stressed and can manage it better - just a walk in the nature and newageyly "being in the moment" is enough, no need for the extremes of youth =)

I have been kind of deep down these rabbit holes of how it works physically. It comes down to some kind of simple principles. Exercise gives your brain more blood. Lifting puts static pressure and conditions vessels and such. Many pro-brain-health hormones get released. The physical actions force a degree of indirect distraction that lets your sub-conscious work as well. These things all combine to promote brain health and problem solving. The brain uses a ton of energy so the blood flow just keeps it well fed.

E: it also makes sure junk from metabolic processes are cleaned up etc.

I don't really know where it came from - but there was this idea that if you are smart you neglect sports - if you are sporty you neglect smarts.

There was jocks vs nerds as a general dichotomy.

Last years we find it more and more to be a false dichotomy.

Just think that you can find "brasilian ju jitsu nerds" or software developers that work out quite a lot.

Not to mention pro-gamers who are not only practicing playing their game - but get physical workout in their training regimen to really go to the top.

Being physically fit IS caring about mental health there is nothing newage-y about it.

There is no mind-body separation, mind is body whether someone likes it or not. If you exercise your muscles to move in a specific way you exercise your mind as well. That is known phenomenon in strength sports - one can build up muscle mass as much as they want but they also have to adapt neural pathways for strength - which is mind.

Sigh. I let myself go weeks without exercising and feel terrible, both mentally and physically.
>> I experience the benefits of exercising as energy balancing.

I find that a lot of fringe stuff like that can be reframed into other fringe or even more "normal" terminology. Which words or metaphors one uses are simply what clicks for them. If "energy balance" is the word that feels right to you, use it. ;-)

i have exactly the same feelings/experiences. i started to ride a bike when pandemic begun and it really improved my comfort of living and ovearll "mental" attitude. its really not about fitness but more like a therapy for a brain to reset. its best to ridea in areas where you can be close to the nature as the presence of nature also contributes
I don't have any references to hand, but drawing from both personal experience and anecdotal stories from places like r/nootropics, the link between cognitive performance and physical exercise is already well established and almost universally accepted. In comparison, brain training games and sudoku puzzles are rarely, if ever, mentioned as beneficial (again, anecdotally). Am I misunderstanding what's being speculated here?

Somewhat related - something that I do find quite curious from my own personal experience is that lifting heavy weights has a far greater impact on my ability to concentrate (and therefore perceived cognitive ability, I guess) than cardio/aerobic exercise does. Like night and day. I've recently started attributing it to creatine supplementation, but I do wonder if there's anything more to it than that.

I think the idea this person has is pretty novel. That physical excercise is great for the mind, not only because it has some nebulous general benefits but because it computationally is a very hard task for the brain. Harder than anything you could throw at it consciously.

It might be wrong but it's interesting and somewhat novel.

Working out makes you more cognitively sharp because it increases the rate of fluid transfer throughout your body and increases metabolism. Ancillary effects of this are calmness, endorphins, and regulated sleep. There I said it, no magic science required. You bring balance in, you get balance out. This ain't the type of cut throat science most of you on HN expect, but sometimes the simple explanation is the one.
The stresses that make body need brains and grow these brains and nervous system as a whole, are stresses that were encountered during evolution: hunger, need to endure (long walk, long work) and need to apply force (run fast, lift heavy).

When body experience these three stresses it produces brain derived neutrotrophic factor [1], which acts as a growth hormone for nervous system as a whole and also grows brain, in areas related to long term memory, higher cognitive functions (language, logic, spatial navigation, etc) and learning.

[1] https://en.wikipedia.org/wiki/Brain-derived_neurotrophic_fac...

It works as if you can build "thinking muscles" which will help in every aspect of life.

E.g., if you barbell squat, you most probably will also run faster and you also will be more stable. Squats are not directly related to running, but they help nevertheless.

If you do endurange training and/or intermittent fasting, you will be more cognitively capable. Endurance training is not directly related to thinking, but it helps nevertheless.

So, yes.

An exercise for general purpose thinking is an exercise.

It's an interesting idea, but I don't think it matches my subjective experience.

I think better when I've been exercising, but it doesn't feel like I've given my brain a workout so much as it feels like I gave it percussive maintenance. It feels like exercise turns the sound of my subconscious from a buzzy rattle to a gentle hum, keeping it out of my way except to help. It very much does not feel like I've given my mind a workout.

Though I also have unmedicated ADHD, so my subjective experience of my subconscious might be different than most.

“Exercise turns out to be the closest thing to a wonder drug that self-control scientists have discovered. For starters, the willpower benefits of exercise are immediate. Fifteen minutes on a treadmill reduces cravings, as seen when researchers try to tempt dieters with chocolate and smokers with cigarettes. The long-term effects of exercise are even more impressive. It not only relieves ordinary, everyday stress, but it’s as powerful an antidepressant as Prozac. Working out also enhances the biology of self-control by increasing baseline heart rate variability and training the brain. When neuroscientists have peered inside the brains of new exercisers, they have seen increases in both gray matter—brain cells—and white matter, the insulation on brain cells that helps them communicate quickly and efficiently with each other. Physical exercise—like meditation—makes your brain bigger and faster, and the prefrontal cortex shows the largest training effect.” - Kelly McGonigal
Cal Newport talks quite a bit in his books (definitely Deep Work, but probably others too) about the linkage between walking or running and thinking creatively and solving hard problems.

In high school, I noted with curiosity that the cross country team had an extraordinary proportion of kids who excelled academically, going to top-tier colleges based on their academic merit alone. I chalked it up to an overlap between the traits required for both distance running and academic excellence: daily persistence, measured in hours, at something that doesn't involve a lot of action or cheering crowds. But there's probably more to it than that.

Military flight training is known to be like medical or law school for many people, spending all day memorizing technical manuals and regulations when not in the cockpit learning to fly. Despite military requirements for physical fitness, and the fact that officers need high fitness scores to get into flight school, many officers let their fitness slide in that environment. I found early on that making time for exercise had a very noticeable effect on my day-to-day performance, both in memorizing stuff and in the cockpit, and I rose to the top of my class. In particular, practicing golf (which involves a lot of finesse, but I also walked and carried my own bag) for a few holes after class every evening seemed to help with learning to execute precise maneuvers on the flight controls.

Trigger warning: Self-promotion here. I'm not selling anything, though.

Your brain is part of your body. It's as simple as that.

I just celebrated 50 years of running: https://albertcory50.substack.com/p/50-years-of-running

I thought long & hard about motivation and how I've kept it up. "Will power" is not it. And I've heard every conceivable excuse about why someone does not exercise. Here's a big one: "people will look at me weird." Or on the flip side, "All my friends exercise, so I have to, too." The great Richard Feynman had something to say about that.

https://albertcory50.substack.com/p/what-do-you-care-what-ot...

And lastly, don't listen to people telling you that you need a regular schedule that you stick to, no matter what. You will never keep that up for long, and if you really hate some exercise, you'll stop:

https://albertcory50.substack.com/p/only-do-exercises-you-li...

Reminder for Hacker News readers to step outside more than once a month so you can realize this naturally instead of applying your booksmart brains to reinvent things that most people not glued to their screens already know.
I believe that the Brain-Computer analogy has been very harmful.

I grew up thinking of myself as a "brain on a stick" - my body didn't really matter and only my brain was important. I think read a bunch of science fiction that made fun of this idea, but I didn't realize it was making fun of it and I took it seriously.

You are not a brain on a stick - your body is important. Developing an understanding of your sensations and emotions is important. Developing an understanding of your deeply held beliefs and assumptions is important. Keeping your body healthy is important.

IME running allows me to solve problems and my theory is that my brain has less capacity to waste because it’s having to concentrate on all those things it needs to propel me safely, leaving my thoughts less cluttered. When I become fit enough I often find myself ‘waking up’ during longer runs, as though I had been in a meditative state. It seems completely plausible that the brain has to do more when running than when solving a puzzle.
This reminds me of something Goggins said, along the lines of working out is almost entirely a mental thing.

You access parts of your brain and your being when you’re giving everything you got to squeeze out that extra rep, or when you are going for a new PR with heavy weight. Or even when you don’t feel like working out, and you say okay I have to get my brain out of this and just do it, similar to life where I have to do work when I sometimes don’t want to.

The physical benefits (muscle mass, testosterone, appearance, strength) for me are entirely secondary to the mental/emotional benefits of working out.

It’s all mental

I’m not sure if going to the gym is more cognitively challenging than sudoku. But something like playing football/socker probably is.
The problem I have with the exercise community is that (usually unintentionally) they made it look complicated and expensive.

A 25 minute walk while listening to a podcast each day has done absolute wonders for everything in my life.

I know plenty of people who exercise a lot and are still idiots. I also used to be very fit, but I only felt cognitively sharper after learning a lot of different complex stuff over time
> So, here’s the speculation / thesis: exercising, that is, operating our bodies at a higher than baseline level, with everything that entails - energy regulation, unconscious balancing, spatial awareness, etc - requires more computing power than crosswords, sudoku, finding relations between measure theory and first-order logic through category theory, etc

Even if this is true (which seems plausible, but I'm not aware of it being proven), I don't think it tells us anything about the extent to which we're looking at "exercise inhibits cognitive decline" vs. "cognitive decline inhibits exercise".

https://en.m.wikipedia.org/wiki/Neurobiological_effects_of_p...

"Neurobiological effects of physical exercise"

Lots of handwavy / subjective comments led me to post this.

Personally I prefer understanding the acronyms as to what's been measured in the body due to regular exercise. No need for anything less than hard detail, imo. BDNF/VEGF expression, etc etc. Worth reading and looking up all the words you don't know yet.

I have found the specific nature of exercise to be very important in this regard.

Moderate cardio is definitely beneficial and helps to maintain some baseline. But, I have never really felt like I "stepped up" to a new level without reaching out to things like HIIT, heavy weight lifting and other forms of plyometrics.

Something about pushing your brain into the "oh shit I don't know if I should be doing this" territory seems to trigger the most powerful effects.

The logic makes sense, especially if you consider sensory negotiation its own special activity using various cognitive tools.

But also, there are some very interesting layers of things going on.

In talking to various athletes about running, the mental process and related result of the activity sometimes seems completely different from person to person to a stark degree.

As an example, some long-distance runners experience running as a de facto journaling exercise, as they are able to benefit from an ongoing internal monologue. So the results are similar to getting free mental wellness care for as long as you care to run.

So, that's also a lot of what we'd call growth and development going on.

They also report that this is unique to running for them, IOW they don't experience this sitting at a desk.

And that's just one example process and outcome, with others being similarly prized, if completely different.

(If this was something I experienced myself, I think I might be a distance runner too... It's pretty cool.)

I’ve got a really obscure personal anecdote. I have cerebral palsy. For all intents and purposes it’s really mild. It only really affects my left hand and slightly my left foot.

I’ve been an average runner at times in my life (10 minute miles up to 15Ks), a part time fitness instructor for slightly over a decade from my mid 20s to mid 30s extra.

What I noticed when it came to anything highly choreographed like dancing or a complex fitness routine and trying to listen to the beat and stay on beat, even though I can physically do the moves, it takes me a lot longer to process choreography than most people. It was mentally much more challenging and tiring than anything I do at my day job (software development).

I don’t see how simple exercise could be cognitive exercise. I could completely zone out while running.

>Robots still have a hard time navigating terrain and manipulating stuff

The author argues that doing things at higher pace should be cognitive intensive. But robots are not bad at doing things fast: if they can do things, they can do them also "fast" (at my understanding)

Single datapoint: I ran 50k per week on average for 1.5 years during Covid. I don’t feel it changed my cognitive ability. I also deeply believe that exercise should make a difference in these areas. I’m at a loss to explain the lack of impact that it had.
There's a recent freakonomics episode that talks about this question (13:18) https://freakonomics.com/podcast/can-you-learn-to-love-hard-...

The host Stephen Dubner sites a piece in psychology today that argues physical activity is strongly connected with cognitive function. https://www.psychologytoday.com/us/blog/the-athletes-way/201...

On a sample of size one. I found that sticking to hard exercise (I am a runner, so intervals, tempo runs, long runs, etc) seems like it is making it easier for me to stick to hard exercise in the future. I have some theories about it (like upping my tolerance for pain) but I think ultimately it all comes down to willpower. If so, it means that willpower can also be exercised and you can increase/improve it to let you do things that are not necessarily pleasurable right now but give you delayed gratification.

Can't tell if it transfers from exercise to my actual work.

The brain is cognitively efficient for physical movements and situations you experience regularly. We experience this subjectively as opportunities to “zone out” or let our thoughts wander as we do the activity. If you run the same route regularly, after a few dozen times you’re probably not thinking much about the running itself anymore.

People learning new activities experience it as the activity “slowing down” subjectively as they learn, giving them more comfort and greater opportunity to think about further improvements. For example learning to ride a bike requires intense thought. But once you know how to ride a bike, it just happens and you can think about where you’re going, or whether you’re in the right aerobic zone, or how fast to take the next jump, etc.

So I would bet that to optimize the cognitive benefit of physical activity, it needs to be somewhat novel. Running on a treadmill or swimming in the same pool or lifting weights in the same gym over and over probably would not do it. You’d need some sort of sport (where other players are constantly creating novel situations) or an outdoor sport where natural conditions are always changing. Or frequently trying new sports or activities.

This is so admirably true. My workout story started at 30. I spent one year doing pull ups, dips, push ups, squats.. various weight training as well. At a certain point I had improved my diet just to change my workouts. I want as many blessings to resonate through me from the universe as possible. I don't even have any preconceptions of what those will be; I have done my best to accept them. The effects of time under tension become remarkable for mental and cardiovascular health if you find a routine you enjoy. Start with a group, friend who goes, many non-national gyms will even have someone let you around if you call in.

For me it was the local park having some shaded calisthenics equipment. Do a search in your area!! There is no pressure there, its outside, there is people of course it improves you! It can teach you all you need to know for atleast 6 months to a year if you let it.

Anyone you come across will either not bother or be very friendly. Most commonly the regulars working out at these parks have a cool and unique mindset and would answer any workout question for you. After a year THEN try all that fancy stuff you would have possibly ego-lifted, struggled/injured yourself on. You will be amazed at your performance.

Exercising is just more honest than using brain, for say, reasoning with words. In the order, I will say 1. Physical Exercise 2. Building Something that stands by itself and works, 3. Solving a well defined problem are all honest undertakings. In real messy world, we deal with ambiguities and people, and it requires some skill reduce them to the above three and be honest about it.
> Recent advances in AI, and less recent advances in computing in general showed that a lot of the things we consider “cognitively hard” - from symbolic manipulation to arithmetic, “drawing” and even reasoning - can be reproduced by computer machinery a lot simpler than we originally thought, at a (likely) higher than human level in the near future Robots still have a hard time navigating terrain and manipulating stuff

...

> So, here’s the speculation / thesis: exercising, that is, operating our bodies at a higher than baseline level, with everything that entails - energy regulation, unconscious balancing, spatial awareness, etc - requires more computing power than crosswords, sudoku, finding relations between measure theory and first-order logic through category theory, etc

I don't buy it. Stuff like "navigating terrain" is something that insects can do often better than robots. It's simply not that hard for animals, which have specialised hardware for this (but on the flipside we lack hardware IEEE compliant floating point units).

Exercise is good because the brain is an organ, and general health is good for organs. And because of psychological factors. General and mental health have a huge impact on cognitive performance.

Cognitive training is not particularly effective because it's a lot of wistful thinking and snake oil (there might be something to it, but I've seen little evidence that it's particularly effective especially when it comes to transfer).

There probably is some cognitive benefit to exercise. Decision making under pressure, discipline, spatial awareness, etc and there would be some transfer to related domains. But I suspect the main effect is just health (which both is better for cognitive performance, and encourages other activities which are good for cognitive performance).

I guess it depends on what one considers "exercise". I don't think lifting weights in disgusting smelly rooms translates improved cognition by itself but I don't mind if people think it does.

That said, I experienced a real physical and mental decline quickly after I gave up my morning routine because it was too hot. I felt it mere weeks into the pause. Pretty ordinary.

Once one has a kid he/she will immediately realize that physical competence is not a luxury but a must-have for basic survival.
Apparently squats are great for mental abilities, compared to other types of exercise.

https://www.bbc.com/reel/video/p09v8wyh/a-simple-exercise-th...

Exercise is healthy. Full stop.

The body / mind paradigm is false. There is no separation. They are deeply - and wisely - entangled.

The brain is an organ, and organs in aggregate benefit from exercise. The result is a healthier system / unit.

Are puzzels and such a bad thing? No. But they're not going to fix a compromised, or too often, broken system.

I’d go as far as to say that the burden of proof is on anybody claiming that regular exercise is not as fundamental as regular eating or regular sleeping or regular breathing. Reductionist, functionalist science has been extremely harmful in shaping how people understand themselves.
Let's suppose for a moment that the numerous studies showing the benefits of exercise don't exist and its influence on cognition is neutral. Shouldn't you move, then? On the contrary - exercise is absolutely necessary for our survival and minimizing the probability of a huge number of illnesses, from cardiac problem to cancers. So a person who is not exercising is basically neglecting their condition.

Now, when you add the numerous cognitive benefits to the equation, you would be crazy not to add some movements to your daily routine. Literally everything counts. I use every opportunity to increase my oxygen and blood flow - and I'm not surprised that the best ideas come when I'm not in front of my computer.

I don't do any workout at all. Nevertheless, I'm very physically active. I work from home, and in general I set my own schedule. Whenever I want, I can open the door, go out, work some in the garden, build something, or do any of the house chores - doing the dishes, making bread, cooking something, fixing something. It keeps me on my feet basically the whole day long.

I've been doing this every single day for the last few months, and it just feels so good, so satisfying. I feel sharp, in form, physically content. I also feel it gives me a solid emotional center, a calmness and a deep feeling of connection to the moment.

The question is, what is the exercise for? We already know from studies that there's very little transfer even between logic-related tasks (say, Sudoku and Chess), so what sort of carry-over could we expect from fitness to logic-related tasks?

I guess the answer will be something like: if you want to be a good programmer in old age, your best preparation is to program a lot and regularly. If you want to be a good mathematician, chess player,...., practice those. If you want to have a healthy body in old age, your best prep is regular exercise. You can do more than one, of course, but you can't substitute one for another.

Socrates love the gym, I cannot recall the exact remarks he said on it but something like this: https://www.artofmanliness.com/health-fitness/fitness/manvot...

Graham (inventor of Graham's number) also juggles quite well. A lot of mathematicians climb. His friend, Erdos do not exercise as much afaik from reading his biography (takes amphetamine...)

I think modern AI or for that matter engineering is fairly broken model for how the human brain or the human body works; and lead to these silly conclusions: It is easy to make a machine that adds two numbers therefor adding numbers cannot be "cognitive hard". Likewise it is easy to make a machine that runs fast, lifts a heavy object or stands one leg therefore ...

As for the most challenging activity for keeping sharp at old age: My guess is directly interacting with other people.

But if you think lifting weights work for you, then I am not going to argue against you.

Interesting piece.

I've heard similar evidence in the past about how physical exercise is "good for the mind". If the author's reasoning about the computational requirements for motion are correct though, perhaps we need to do a bit of digging into why yoga/meditation is also supposedly quite "good for the mind", and yet they are significantly less complex from a motion standpoint than things such as martial arts/dancing/sports - which don't have the same reputation. Would love to see some research done though!

There's a lot of literature on various kinds of cardio (esp HIIT and 'zone 2') and lactate production -> BDNF which is loosely understood to be very important for your brain.

Some more recent stuff on myokine release (from strength or cardio training) and warding off cognitive decline. Similar with training your balance (a parameter in exercise that is often forgotten).

More speculatively: crosswords and sudoku seem fine, but what about something much more cognitively demanding like doing serious mathematics?