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Medical Strange questions about language/energy

  1. Jan 20, 2010 #1

    fluidistic

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    Sometime when I'm tired, I'd rather make hand gestures (like an instinct in me) than opening my mouth and pronouncing sounds/intelligible words. I wonder which of the 2 requires more energy to our body.
    As I read that swinging our arms when walking costs us 10% energy less than non swinging them, I also wonder why, in the case that moving hands/fingers costs us less than talking, we didn't develop such a skill.
    A bit off topic: maybe obese people should try not to swing their arms when walking?

    Edit: Have you experienced the same feeling, i.e. wanting to make gestures instead of talking? I do experience it several times a week. I don't know why, but I'm very tired although I sleep about 8 hours a day and in a somewhat good bed.
     
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  3. Jan 20, 2010 #2

    lisab

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    Do you know sign language? Did your parents teach you signs when you were an infant?
     
  4. Jan 20, 2010 #3

    fluidistic

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    I know about it but I don't know it. I never been taught it.
     
  5. Jan 20, 2010 #4

    DaveC426913

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    I assume when you said "obese people" what you really meant to say was "people wishing to exercise and get/keep in shape"? The two groups overlap but they are by no means synonymous. Hmm?

    Something I heard recently is that you can get more exercise out of a walk by - not merely stopping swinging, but swinging your arms in the opposite phase than what is natural. i.e. put left arm forward with left foot forward. Apparently this can nearly double the calories burned.
     
  6. Jan 20, 2010 #5

    fluidistic

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    I meant overweighted people. If they are not willing to change their habits (of not doing exercise) and/or if they don't have time to exercise, they could at least try not to swing their arms.
    This is awesome, I just tried it, it's so funny!
     
  7. Jan 20, 2010 #6

    DaveC426913

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    OK well, I gave you a chance...

    What you have said is ignorant and prejudiced. You have no business generalizing about overweight people.

    The people you should be talking about is people who wish to exercise and get a little more out of their walk.
     
  8. Jan 20, 2010 #7

    fluidistic

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    Ok. I don't mean to offence anyone. Notice the "and/or" part.
    I think that if one needs to do some exercise but for some reason (unwillingness, impossibilities due to time constraints) cannot do it, at least he could change its way of walking, if possible of course. That's an idea. I think that most people aren't aware they can "burn" calories this way.
    Sorry if I offended you or anyone. It's not my goal.

    My goal is to get answers from my bold questions in the first post and to know whether people have experienced the same feeling or not.
     
  9. Jan 21, 2010 #8
    I often make gestures and move my hands around when I talk to people. Usually its because I have some picture in my mind dealing with what I'm talking about and I'm trying to convey that information to the person I'm communicating with. Sometimes hand gesturing helps me to remember the correct words to express my ideas.
     
  10. Jan 21, 2010 #9
    Are you thinking hand gestures might require less energy, which is why you resort to them when tired?

    I think, for you, the hand gestures might well represent less mental effort, which is probably a different animal than less energy.
     
  11. Jan 21, 2010 #10

    fluidistic

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    Yes.
    Interesting. In fact it occurred to me but I discarded it. It's true that when you're tired you don't feel like forming long sentences. You'd rather just answer by "yes", "no", etc. Turning the thumb up and down doesn't seem very hard compared to pronounce sounds.
    But I'm curious, why when we're tired we would avoid to use "mental energy" instead of just physical energy? Although I know the brain uses quite a lot of energy, I don't think that thinking a sentence requires more energy than say, lefting up an arm.
    It does not totally convinces me that I'd use less mental energy since I feel I could start a conversation with gestures (yeah I do think long sentences, but I'm so tired I won't speak), even if I have to form long sentences. But it pisses my girlfriend (I live with her) so much that I don't have the opportunity.
     
  12. Jan 21, 2010 #11

    Evo

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    This doesn't make any sense Dave, can you post a link to the study that measured this?
     
  13. Jan 21, 2010 #12

    DaveC426913

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    Here's a reference to a study:
    http://www.physorg.com/news168027773.html
    OK, only 25% then.

    buuuut ... if holding arms still raises metabolism by 12%, and swinging opposite raises it by 25%... that's sort of double... :tongue2:



    But all you have to do is try it. It's difficult to do, it works many more muscles (because it's not conservative of motion); there's no question that it'll burn more energy.
     
    Last edited: Jan 21, 2010
  14. Jan 21, 2010 #13

    Evo

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    Unfortunately that's not a real medical research study, that's a chiropractic clainm with no science to back it up.
     
  15. Jan 21, 2010 #14

    DaveC426913

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    OK.

    Are you refuting the numbers, or are you refuting (my) claim that swinging one's arms opposite will burn more calories than the more natural walk?
     
  16. Jan 21, 2010 #15

    atyy

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    http://rspb.royalsocietypublishing.org/content/276/1673/3679.long
    Proc. R. Soc. B 22 October 2009 vol. 276 no. 1673 3679-3688
    Dynamic arm swinging in human walking
    Steven H. Collins, Peter G. Adamczyk, Arthur D. Kuo
    Humans tend to swing their arms when they walk, a curious behaviour since the arms play no obvious role in bipedal gait. It might be costly to use muscles to swing the arms, and it is unclear whether potential benefits elsewhere in the body would justify such costs. To examine these costs and benefits, we developed a passive dynamic walking model with free-swinging arms. Even with no torques driving the arms or legs, the model produced walking gaits with arm swinging similar to humans. Passive gaits with arm phasing opposite to normal were also found, but these induced a much greater reaction moment from the ground, which could require muscular effort in humans. We therefore hypothesized that the reduction of this moment may explain the physiological benefit of arm swinging. Experimental measurements of humans (n = 10) showed that normal arm swinging required minimal shoulder torque, while volitionally holding the arms still required 12 per cent more metabolic energy. Among measures of gait mechanics, vertical ground reaction moment was most affected by arm swinging and increased by 63 per cent without it. Walking with opposite-to-normal arm phasing required minimal shoulder effort but magnified the ground reaction moment, causing metabolic rate to increase by 26 per cent. Passive dynamics appear to make arm swinging easy, while indirect benefits from reduced vertical moments make it worthwhile overall.
     
    Last edited: Jan 21, 2010
  17. Jan 21, 2010 #16
    I know that part and parcel of falling asleep is that the brain stem sends the message to the thalamus to lower brain activity in the cortex. It makes sense to suppose that physical activity isn't lowered in lockstep with mental activity because we're often tired before we're in a position to actually sleep and need a bit of physical energy and coordination to get to a place we can let go and "crash". So, I think the physical energy you have left to gesture after your language cortex is already on it's way to sleep mode is probably from the same reserve of physical arousal being allowed for you to get up and relocate to your bed.
     
  18. Jan 22, 2010 #17
    This is a bit off topic, but I love the subject of hand gestures accompanying speech. I am especially entertained by girls who spontaneously pepper their speech with cute and clever illustrative hand gestures in support of, and sometimes in place of, words.
     
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