
Does extra mental effort burn more calories? - robg
http://www.nytimes.com/2008/09/02/science/02qna.html?ref=science
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ars
I don't think he's right. At least what he said doesn't match every other
place I've researched this topic. For example:
<http://answers.google.com/answers/threadview?id=381608>

Which says it goes up by 50%, i.e. an extra 125 calories per hour. He says
"But you do not engage that long in such an activity" - maybe he doesn't. But
I think most of the people here do.

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xiaoma
"...so the brain uses roughly 300 calories.

“There are good, sophisticated studies that show that concentrated mental
activity, like doing a difficult multiplication problem in your head,
increases the glucose uptake to the brain,” he said. By how many calories?
Less than, say, 20 calories of the 300, he estimated."

If it's an _increase_ of 20 calories, then why is the total still 300?

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pasbesoin
Maybe I'm fooling myself, but I definitely notice/perceive the need for
glucose after extended concentration. Whether from a longer respite and a good
meal, or from a modest intake of something like soda. With the latter, though,
it is difficult to keep from overindulging and inducing a sugar buzz/crash
cycle.

~~~
pgebhard
Yeah, I agree. When I took long tests like the SAT or college final exams, I
definitely noticed the drain. I needed some sugary drink/candy (or just beer)
afterward, for sure.

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ryanmahoski
In a way, it depends on how we define mental effort. If you concentrate on
raising your heart and breathing rates - which are physical, but then so in a
sense is mental effort - you can significantly affect calorie burn.

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byrneseyeview
Right, and if you decide to run a marathon or become an Olympic athlete, that
mental effort is going to burn even _more_ calories. So I think it's clear
that they're talking about calories burned by the mental activity, not
calories burned by physical activity that was the result of mental activity.

~~~
imgabe
I don't think that's what he meant. There is some evidence that with training
some people can raise their heart rate or body temperature purely by thinking
about it.

<http://www.hno.harvard.edu/gazette/2002/04.18/09-tummo.html>

~~~
stcredzero
I had one girlfriend who became like a furnace when she slept. She slept with
no covers with the window open in January in Ohio. I had to strip down to just
one sheet. Literally, it was like sleeping next to a space heater. So it is
possible for the body to increase its metabolic rate.

~~~
LogicHoleFlaw
For the purposes of temperature control in places with _extremely_ tight
environmental requirements, the modelling assumption is that a human being
gives off the same amount of thermal energy as a standard 100-watt
incandescent lightbulb. When you check into the clean room, you turn off your
bulb. When you leave you turn it back on. The bulbs also serve as a handy way
to tell who is in the lab that day :)

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deathbyzen
No wonder I'm so fat. I'm suing the LOLCats for mental anguish/physical
distress.

~~~
river_styx
I'd actually like to see a controlled study on the effect of LOLcats on IQ.
And the effect of reddit/digg/4chan (reddiggchan?).

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hooande
If I have to decide between doing algebra or jogging to burn calories...I'll
take a lap

