6 ms·

How Exercise Affects Our Memory

86 points by erickhill 7y ago

jdhn 7y ago
I wonder if those who primarily benefit from exercise based are primarily older people. If it's not, then either I need to see a neurologist, start exercising harder/more frequently, or both.
opportune 7y ago
Sample size: 26. Confounding variable: all older people. Also the exercisers did not perform significantly better in the memory test! They only had higher activation in the regions of the brain associated with memory! Really a garbage conclusion from the actual article
- yjftsjthsd-h 7y ago
  ... Isn't increased brain activity a sign of worse performance? Because when your brain is actually operating efficiently, it doesn't need to light up very many neurons to do what it needs to do.
  - ip26 7y ago
    On the other hand, forgetfulness and memory loss is associated with simply losing access to the neurons. If your memory bus was faulty, DRAM would be pretty quiet.
  - antris 7y ago
    This is literally what is said in TFA: > Less activity suggests that the brain had become more efficient at semantic-memory processing as a result of the exercise, requiring fewer resources to access the memories.
    - maxerickson 7y ago
      It's clear in the paper that their result is the other way around, exercise was correlated with higher activation intensity. https://www.cambridge.org/core/services/aop-cambridge-core/content/view/07DE0F919CEFBCE268A95474DFA1BC47/S1355617719000171a.pdf/semantic_memory_activation_after_acute_exercise_in_healthy_older_adults.pdf https://www.cambridge.org/core/services/aop-cambridge-core/c... The activation intensity isn't necessarily a measure of efficiency anyway. There wasn't a difference in blood flow, so energy use would have been similar.
  - jfoutz 7y ago
    Not hard to imagine the degenerate case though. Hey, remember X? Nope. Checking more things before returning the negative result might be better.
- maxerickson 7y ago
  The memory test was designed not to measure performance (the names presented were preselected so that performance with each of them exceeded 90%). For a real effect, a sample size of 26 is going to show it just fine.
  - mruts 7y ago
    Depends on the effect size.
- sonnyblarney 7y ago
  Surely. But I know that this is true for me. I can tell at the end of the day whether I worked out or not just by how I feel. Without workouts I feel foggy, slow, unmotivated. Doing cardio I feel 25. Same for others so I hope they continue this research.
bumby 7y ago
I think there's decent evidence that low intensity exercise can increase BDNF which helps increase neural connections. Not really the same as this study, but a different effect of exercise on the brain
- pishpash 7y ago
  Methinks sleep increases memory performance more.
  - hinkley 7y ago
    If exercise helps you sleep better, A -> B -> C
    - LeonB 7y ago
      Sleep helps you exercise better moreso than the inverse.
- 0xcde4c3db 7y ago
  As I recall there is such evidence, but there's also evidence that commonly encountered concentrations of particulate air pollution drastically reduce that increase in BDNF. So it's not entirely clear what mechanisms all have to be working well to see that particular benefit.
hawaiian 7y ago
Anecdotally, long periods of exercise (cycling 50+ miles in a single session, once a week) seem to nuke my short-term memory for a few hours, but over time this habit seems to have improved my short-term memory for things such as phone number extensions.
- brian_cunnie 7y ago
  I have the same experience after rugby matches and open water swimming — my short-term memory is shot for the next few hours, but then it recovers. I have no evidence for the long-term effects.
interfixus 7y ago
Hardly even anecdotal, just my personal experience: I always disliked sports, and I would't dream of entering a 'fitness center' or whatever they're called. I do a minute or two with hand-weights every morning, I walk my dog, and I bike [pedals, not motor] a bit - the oldfashioned way, nothing fancy or spandexed about it. But am often puzzled by everyone's physical passivity: I don't really get the point of escalators, for example. I tend to trot up the stairs if they are available, in the process generally overtaking the stand-still folks on the conveyor. It seems to work: I'm sixty and in very decent shape and excellent health. As for kickstarting my brain when it goes mushy, honestly I find driving at least as efficient as walking or biking. Change of scenery, not having to think, seems to do the trick for me.
x11 7y ago
It might sound dumb, but whenever I'm stuck and I need to solve a hard coding problem, a long walk does the trick.
- agumonkey 7y ago
  Do trips also work (car, train, or else) ? Also being in a different location unleashes a lot of inspiration very often.
sriram_malhar 7y ago
IIRC, I exercised yesterday.

86 points by erickhill 7y ago

jdhn 7y ago

I wonder if those who primarily benefit from exercise based are primarily older people. If it's not, then either I need to see a neurologist, start exercising harder/more frequently, or both.

opportune 7y ago

Sample size: 26. Confounding variable: all older people. Also the exercisers did not perform significantly better in the memory test! They only had higher activation in the regions of the brain associated with memory! Really a garbage conclusion from the actual article

yjftsjthsd-h 7y ago
... Isn't increased brain activity a sign of worse performance? Because when your brain is actually operating efficiently, it doesn't need to light up very many neurons to do what it needs to do.
- ip26 7y ago
  On the other hand, forgetfulness and memory loss is associated with simply losing access to the neurons. If your memory bus was faulty, DRAM would be pretty quiet.
- antris 7y ago
  This is literally what is said in TFA: > Less activity suggests that the brain had become more efficient at semantic-memory processing as a result of the exercise, requiring fewer resources to access the memories.
  - maxerickson 7y ago
    It's clear in the paper that their result is the other way around, exercise was correlated with higher activation intensity. https://www.cambridge.org/core/services/aop-cambridge-core/content/view/07DE0F919CEFBCE268A95474DFA1BC47/S1355617719000171a.pdf/semantic_memory_activation_after_acute_exercise_in_healthy_older_adults.pdf https://www.cambridge.org/core/services/aop-cambridge-core/c... The activation intensity isn't necessarily a measure of efficiency anyway. There wasn't a difference in blood flow, so energy use would have been similar.
- jfoutz 7y ago
  Not hard to imagine the degenerate case though. Hey, remember X? Nope. Checking more things before returning the negative result might be better.
maxerickson 7y ago
The memory test was designed not to measure performance (the names presented were preselected so that performance with each of them exceeded 90%). For a real effect, a sample size of 26 is going to show it just fine.
- mruts 7y ago
  Depends on the effect size.
sonnyblarney 7y ago
Surely. But I know that this is true for me. I can tell at the end of the day whether I worked out or not just by how I feel. Without workouts I feel foggy, slow, unmotivated. Doing cardio I feel 25. Same for others so I hope they continue this research.

bumby 7y ago

I think there's decent evidence that low intensity exercise can increase BDNF which helps increase neural connections. Not really the same as this study, but a different effect of exercise on the brain

pishpash 7y ago
Methinks sleep increases memory performance more.
- hinkley 7y ago
  If exercise helps you sleep better, A -> B -> C
  - LeonB 7y ago
    Sleep helps you exercise better moreso than the inverse.
0xcde4c3db 7y ago
As I recall there is such evidence, but there's also evidence that commonly encountered concentrations of particulate air pollution drastically reduce that increase in BDNF. So it's not entirely clear what mechanisms all have to be working well to see that particular benefit.

hawaiian 7y ago

Anecdotally, long periods of exercise (cycling 50+ miles in a single session, once a week) seem to nuke my short-term memory for a few hours, but over time this habit seems to have improved my short-term memory for things such as phone number extensions.

brian_cunnie 7y ago
I have the same experience after rugby matches and open water swimming — my short-term memory is shot for the next few hours, but then it recovers. I have no evidence for the long-term effects.

interfixus 7y ago

Hardly even anecdotal, just my personal experience: I always disliked sports, and I would't dream of entering a 'fitness center' or whatever they're called. I do a minute or two with hand-weights every morning, I walk my dog, and I bike [pedals, not motor] a bit - the oldfashioned way, nothing fancy or spandexed about it. But am often puzzled by everyone's physical passivity: I don't really get the point of escalators, for example. I tend to trot up the stairs if they are available, in the process generally overtaking the stand-still folks on the conveyor. It seems to work: I'm sixty and in very decent shape and excellent health. As for kickstarting my brain when it goes mushy, honestly I find driving at least as efficient as walking or biking. Change of scenery, not having to think, seems to do the trick for me.

x11 7y ago

It might sound dumb, but whenever I'm stuck and I need to solve a hard coding problem, a long walk does the trick.

agumonkey 7y ago
Do trips also work (car, train, or else) ? Also being in a different location unleashes a lot of inspiration very often.

sriram_malhar 7y ago

IIRC, I exercised yesterday.