Bigger brains?

[wal]

Does it say in this study that "physical activity" apart from other benefits increases brain size regardless of genetic make up?

http://www.theage.com.au/lifestyle/d...05-13vsz5.html

http://www.ncbi.nlm.nih.gov/pubmed/25003773

Or is it just a load of nonsense?

[Tom Campitelli]

I have not read the full text of the article, so I cannot comment on it beyond what is presented in the abstract. However, the increase in gray matter volume is the observation for which the authors claim the lowest P-value. For those who are not familiar with it, the P-value is a commonly abused test for statistical significance. If we assume the null hypothesis to be that there really is no difference between the brains of the twins, the low P-value would help to eliminate the null hypothesis as true. According to the numbers the authors provided, there appears to be a real difference in their gray matter volumes. The idea that exercise has an effect on the brain is not a new one and, if done correctly, perhaps this study helps to support that. That physical activity appears to be good for us probably is not a big surprise, either.

Medical and statistical peeps may have things to add here.

[tweakxc03]

this explains my recent bouts of telepathy.

[hugenscrawny]

There's some type of correlation to brain size and body mass i believe. Not linear and different between species. But generally we might be able to assume it's a response to increase in body mass since lifting.

[Tom Campitelli]

There's some type of correlation to brain size and body mass i believe. Not linear and different between species. But generally we might be able to assume it's a response to increase in body mass since lifting.

The authors didn't specify that these people were lifting, nor that the twins who exercised had more body mass. They only mention the physically active ones tended to have lower body fat percentages. I don't know that we could assume that an increase in body mass even occurred, nor that it caused a difference in the gray matter volume.

[hugenscrawny]

The authors didn't specify that these people were lifting, nor that the twins who exercised had more body mass. They only mention the physically active ones tended to have lower body fat percentages. I don't know that we could assume that an increase in body mass even occurred, nor that it caused a difference in the gray matter volume.

I'm just throwing thoughts out there.

Although the area of the brain that increased related to motor control etc Brain size to body mass correlation isn't so much to do with mass obviously but gray matter required to operate such large machinery/organs. I was suggesting maybe the inactive twin has less muscular mass his body can operate (due to absence there of or low efficiency).

[wal]

This study appears say that genetics and evironmental factors are not part of the gains made by "physical activity". In other words improvents and I would say also strength gains are not governed by such limitations and you will only get out of any training what you put in to it. Fair enough?

[Tom Campitelli]

This study appears say that genetics and evironmental factors are not part of the gains made by "physical activity". In other words improvents and I would say also strength gains are not governed by such limitations and you will only get out of any training what you put in to it. Fair enough?

I don't understand what you wrote. Does exercise not count as an environmental factor?

[wal]

I don't understand what you wrote. Does exercise not count as an environmental factor?

I don't think so, exercise or training in this case for myself strength training is not the envirionment it is only what I do in the environment wherever or whatever that may be, here or over there, in the heat or the cold, well that's what I mean by envrionment, it should not be a limitation to a predetermeined training goal.

That study to seems to be stating the flaming obvious, that two identical people can get two different outcomes by the the exercise program that they do or don't do, one could run all day the other could do a strength training routine and I bet you would see a difference. The study seems to say genetics and the evironmental background should not be limitating factors.

Look, I can tell you since doing Rippetoe's SS I have got smarter, I now let the Mrs do all the cooking, Ha!

[Tom Campitelli]

Physical activity probably should be considered part of the environment in which an organism lives. If you have two bins that influence how an organism develops, one being "genetics," the other being "environment," physical activity belongs in the latter. It serves as an external stressor which causes the organism to adapt. The hypothesis that exercise has an impact on gray matter volume in certain areas of the brain is neat. This seems to back up that claim.

The study seems to say genetics and the evironmental background should not be limitating factors.

I would argue that genetics and environment encompass ALL of the limiting factors in how an organism develops. The study, which neither of us have read in full, attempted to control for genetics. That is, you have two people with identical genetics. Given the presence or lack of the external stressor of exercise, they found measurable differences in certain physical traits, most of which are not terribly surprising, but are kind of cool.