How exercise boosts brain health | Hacker News Reader

How exercise boosts brain health

kurzweilai.net

119 pointsca98am7942 comments

I did some research into when diminishing marginal returns to exercise kick in. I eventually found this excellent study http://ije.oxfordjournals.org/content/40/5/1382.long

which indicated to me that ~1000Cal/week expended in a vigorous fashion should be what I shoot for. This means that stuff that elevates post exercise oxygen consumption like resistance training and interval training for cardio are great bangs for your buck. This jives well with other research on the health benefits of these activities. I'm currently hitting the threshold with 2 days/wk of HIIT and resistance training each.

Remember that the human body is adapted to frequent physical exercise. So the story would really be more accurate to say that lack of exercise impairs brain function due to less release of irisin.

Perhaps a small difference in wording, but I think the change in perspective is important.

Nearly everything about human physiology can be thought about what would have worked for hunter-gathers. We're specialised in some areas, most of which doesn't require a constant practise (e.g. a 60 year old can start training for a marathon). But the one of the basics of that life was daily exercise, it's a shame it appears avoidable to us now.

Of course, "daily exercise" may have simply included what amounts to a long walk, no? Not everything was heavily labor based. Certainly not year long.

More, if you go far enough back (not actually that far, frighteningly) and things like "respect for the life of others" drops out rather sharply.

So.... what, exactly, is the lesson here? My takeaway is that rose colored glasses can make even some of the most horrid of conditions (human history), somehow look good. Me? I'll take the present where I have a reasonable expectation that my kids will not die before me. By a long shot.

My understanding is that we're basically built to be walking ~8 hours most days. So yes, a long walk... but longer than most of us can fit in.

I would find that a little tough to believe. I could see long walks occasionally, but sustained walks of ~8 hours a day just doesn't make sense. Where would we have been walking? Just giant circles?

Wherever food seemed to be, I imagine.

Google "wolf run hours per day". Where do they run?

"... the Hadza, a population of traditional hunter-gatherers living in the open savannah of northern Tanzania. Despite spending their days trekking long distances to forage for wild plants and game, the Hadza burned no more calories each day than adults in the U.S. and Europe. The team ran several analyses accounting for the effects of body weight, body fat percentage, age, and gender. In all analyses, daily energy expenditure among the Hadza hunter-gatherers was indistinguishable from that of Westerners."

http://www.sciencedaily.com/releases/2012/07/120725200304.ht...

From what I've read, I think I'll gladly take the physiology forced upon me by what hunter-gatherers were used to, over what subsistence farmers were used to.

> it's a shame [daily exercise] appears avoidable to us now

Unless you're elderly, sick, or disabled. Then making long walks, jogging, and sprinting optional is literally a life-saver.

There's no question about this personally.

It's why I started exercising about 18 months ago, because I realized my ability to concentrate had faded as my fitness had decreased. I couldn't stand it any more and had to fix it.

It's made a huge difference.

what do you do? What's your routine?

I am not the post to whom you replied, but to share my own routine (similar thing, started seriously pursuing fitness over the past 8 months or so and have noticed a lot of cognitive reward):

- Every morning except Sunday I'll do some form of cardio; first I did C25K, then random biking, now I'm doing a sprint regimen (from half-awake to dead legs in like eight minutes; talk about bang for your buck)

- Lift every other day doing a simple weights program (started off doing Starting Strength, moved to bodyweight stuff, now back on Starting Strength)

- On weekends I do something fun: co-ed frisbee/soccer leagues are a dime a dozen and will give you quite the workout. The past few weekends I've been going to a climbing gym, which has been awesome.

I had this idea in my head that improving my level of fitness was this Herculean task that would take hours a day, but it's really not. I spend roughly thirty minutes a day working out.

I've found starting strength to be a lot of fun and very beginner friendly (apart from the overhead press anyway). I'd suggest anyone who wants to get into lifting follow it, nothing feels better than going from squatting 0 to 200 lbs in the course of a few months.

Ditto for SS, I have no idea how well it compares to other programs but for the sense of progress (weight increases every time) it cannot be beaten.

Good if you have tried and then quit the gym before. I also recommend fitocracy.com (or any other sites of that ilk) to "game-ify" exercise a bit and keep you motivated.

I do mostly cardio. 45 minutes walking 3 miles in the morning, 45 minutes on a stationary bike at night. I do pushups as well, but that's it for anything resembling strength training.

I was completely sedentary before that, and I've lost about 100 pounds since Jan 1 of this year. Eat less, exercise some. Made a big cognitive difference.

cool, this is more my speed. I don't really want to join a gym cause I get bored in them but I live in a city where I can walk or bike to work (by subway it's 30min) and I'll probably try and do stuff like that more often. I also take the stairs to my office 4 flights up instead of the elevator

Does the underlying article, which is not linked to, specify quality and quantity of exercise necessary to experience the benefit?

Can't comment on this one in particular, but the threshold most often set forth for this or that health benefit from exercise is 30 minutes of elevated heart rate a day, aka 3-5 hours a week.

The experiments were conducted on mice so probably have little applicability to humans. For what it's worth, the experiment used mice housed in cages with access to a running wheel for 30 days of voluntary excessive. The control group did not have running wheels.

As the husband of a neuroscience researcher who works with a mouse model, I believe you'd be surprised at the applicability of such research towards human analogues.

What did the other mice do? Just sit around, doing nothing?

John Ratey (http://en.wikipedia.org/wiki/John_Ratey), the professor of psychiatry at Harvard Medical School who wrote Driven to Distration, recently published a book called Spark: The Revolutionary New Science of Exercise and the Brain (http://www.amazon.com/Spark-Revolutionary-Science-Exercise-B...).

Spark details how high-intensity cardio (like sprints or interval training) put your brain chemicals in balance in part by generating BDNF (http://en.wikipedia.org/wiki/Brain-derived_neurotrophic_fact...), which as Ratey describes, it's like "Miracle-gro" for the brain.

Last year my stress levels were getting out of control from working too much. At the time I was running at least two miles every day so it's not like I wasn't exercising. But then one day I changed from running a couple miles to running 50-yard sprints, as fast and as hard as I could push myself. The first day I only ran four sprints, but I felt euphoric the rest of the day -- the best I had felt in years. So I tried it again a couple days later, and sure enough it worked again -- I felt amazing.

So then I had to find out why this worked -- why a few sprints were so much more effective than running several miles. I started Googling and eventually found Ratey's book -- it explains the entire biochemical process of what's going on and why sprinting works.

It's an eye-opening read. Each chapter covers how high-intensity cardio affects things like stress, anxiety, depression, ADHD. I have ADHD but haven't taken anything for it in years (since I was in college), and I can attest that sprints not only fixed by stress levels, but my ADHD symptoms were almost non existent.

Here's a key point that Ratey makes throughout the book that completely changed my perspective on things -- he says that instead of thinking of exercise as something you should do to look good and build a healthy body, you should instead think of exercise as the key to building a healthy brain: "We all know that exercise makes us feel better, but most of us have no idea why. We assume it’s because we’re burning off stress or reducing muscle tension or boosting endorphins, and we leave it at that. But the real reason we feel so good when we get our blood pumping is that it makes the brain function at its best" (http://www.sparkinglife.org).

In the book's introduction he goes on to say, "Building muscles and conditioning the heart and lungs are essentially side effects. I often tell my patients that the point of exercise is to build and condition the brain."

In fact the brain exercise routine he recommends is similar to a weight workout routine, in that you have to push yourself hard one day, and then take a day off to let your brain recover, just like in weight training. Another key is when you sprint, always put everything you have into it. Run as fast and as hard as you can so you are constantly pushing your body and your brain past their limitations -- this is the key to growth.

Reposted from: http://news.ycombinator.com/item?id=5323019

A bit pedantic, but I'd like to defend endurance running - comparing 2 mile runs to really pushing yourself with HIIT is unfair. At 5mph (a slow pace) that's only 24 minutes, which is usually not enough time to even experience a runner's high and about when you get settled into a rhythm as a distance runner.

If you only have 30 minutes you're indisputably better off sprinting.

As a practical matter, very few over 30s can keep up a regular sprinting habit without injuring themselves. HIIT running may be better in theory, but it doesn't work out that way in real life.

I find that even at 20 it's very easy for me to cause joint issues after several years of inactivity. If you do too much too fast it'll cause problems no matter your age - although I'm sure age is something that you should take into consideration.

If you're concerned, there are alternatives like swimming and biking that are lower impact.

You can do HIIT in many low-impact sports. Swimming comes to mind, but there are plenty of great high intensity sports which work with agin bodies.

Most coastal areas probably have outrigger paddling clubs or dragon boats or crew. I can't recommend outrigger canoe paddling enough.

I strongly recommend rowing. Full body, low impact, and you can do it in your home, which lowers the activation cost a lot.

A good alternative is tabata [1] sessions on the rower. 20 seconds as hard as you can 10 seconds very gentle (just to keep the timer going). Do it 8 times for a total of 4 minutes - it starts to get pretty grim around the 4th sprint. It's a great finisher or warm up :-)

[1] http://tabatatraining.org/

This has been absolutely true for me. Both lifting, olympic style compound lifts and cardio have made a measurable difference in my ability to concentrate and problem solve.

I've also measured a marked increase in retention when memorizing GRE words while jogging over memorizing them while sitting. That experiment inspired me to put together this website: http://rungre.com (shameless yet hopefully relevant plug)

Has anyone else tried to combine studying and exercise?

One of my favorite quotes from growing up was from my martial arts class, we had this trainer who would come over a couple of times a year from Israel - and during one session where we were doing particularly interesting movement, he said: "These movements open up dormant brain circuitry" -- it was a statement that always stood out to me.

I'm actually about to shift my workflow in a major way to include more movement. Already use an adjustable desk, standing in the morning and sitting in the evening. And when I'm on calls, I always use a headset and walk-n-talk.

That's good and all, but activity does not replace exercise.

Completely agree, as I do with the comments below. A wide range of "real" exercise, from high-intensity training to endurance and flexibility, has and will continue to be a part of my life.

My comment was just on the narrower idea of making the insane number of hours I (and most people) spend in front of a screen or on calls every day a whole lot less sedentary.

Might want to go so far as to consider a treadmill when you're on your headset when you're doing your walk n talk.

This is very far from exercise but it might feel to you as exercise and an increase of movement because your perspective on the physical abilities of the average human is skewed. One astonishing thing I've learned while becoming more active is what a normal body is really capable of without going into the realm of professional athletes. Running a marathon with a slow pace is really feasible. So is lugging a 15-20kg backpack for 35-40km per day for about a month or rock climbing/bouldering in the lower difficulties. To achieve either of it you wont need a very hard exercise regimen either, rather persistence.

Please don't take this as personal criticism. I just find it important to point out that there is a huge gap between what people unfamiliar with sport perceive as achievements and what actually are achievements. Just put in 4 hours of running and 4 hours of climbing per week and you will see for yourself.

Edit: Or I just failed to see the sarcasm in your post. Entirely possible :)

He just said that he intends to include more movement in his daily routine [0]... nowhere did he say that it was exercise, or sport, or a physical feat.

Seriously. Why do all of you born-again iron men have to come out of the wood-works as soon as people start sharing (not even bragging) their incremental efforts (you said it yourself: persistence) to lead healthier lives? We get it: you are better than them when it comes to fitness (well, the grandparent could be a former Olympian, for all we know. Or he might be an amateur sportsman who also has a sedentary job). Please stop one-upping people that are just getting off their feet when it comes to this.

[0] The importance of which seems to be distinct from exercising regularly, at least if you don't have time to exercise for hours on end each day:

http://www.theguardian.com/lifeandstyle/2012/oct/21/is-sitti...

See my comment above. I've actually been an entrepreneur, teacher, trainer and comptetitor in the health and fitness field for the better part of the last 15 years. But the last few have seen a lot more screen time, so I'm doing what I can to change that.

You're a massive douche.

More and more scientific confirmation of "mense sane in corpore sano"

often translated as, "A sound mind in a healthy body."

http://en.wikipedia.org/wiki/Mens_sana_in_corpore_sano

Distance runner here. This may may not seem medically sound, but I have this theory that mental exhaustion and physical exhaustion are inversely proportional to an extent.

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