The Five Biggest Contradictions in Fitness
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The Five Biggest Contradictions in Fitness

Itís no secret that when people contradict themselves, it has the effect of making the flaws in their actions or statements seem glaringly obvious. But what about when WE ourselves get caught contradicting ourselves by someone else?

By: Nick Tumminello Added: January 6th, 2014
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  1. #1
    Pot-bellied bean pole Big & Tall's Avatar
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    Efficiency of muscle

    I was wondering what is the efficiency of human muscle? For example, how many kilocalories does one burn in order to, say, increase the potential energy of a bar while bench pressing. Of course, simple PE calculations wouldn't quite work--you'd really have to look at an integral of acceleration (~force) over a range of motion to calculate the actual work done, but you get the idea.

    Similarly, when doing cardio, you are essentially working against a brake dynomometer. Is the number of calories burned reported by the machine a direct representation of the work disipated by the dyno, or is it modified by some average efficiency value?

    Yes, I was bored, and yes, I am an engineer.
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  3. #2
    el imposible ectx's Avatar
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    Here's the catch. BIological systems are very different from mechanical systems. Muscular efficiency is calculated on multiple levels with a high degree of variability. this is not a pure science like physics and chemistry. Think about it...what will govern it's efficiency:
    temperature
    fuel source
    efficiency of metabolic enzymes
    cellular permeability
    fiber composition
    rate of nutrient delivery.


    Within each is a series of variables that provide even greater variability...

    ie. for each metabolic enzyme or delivery molecule efficiency will vary because of variation in the molecule's structure.

    or

    ie. The rate of transcription for a particular enzyme or molecule.

    Can you see where this starts to get very complicated?

    It's not a simple formula answer. And this, my friend, is why drugs cost outrageous amounts of money.
    ecDoesIt

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  4. #3
    Maki's parole officer Pudgy's Avatar
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    ouch my brain
    of all the people i ever met , ive had the most trouble with myself.

  5. #4
    One crazy MOFO/Mail man
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    mgh*k
    where k is the coefficient of efficiency which in reality can only be measured on a case bay case basis but in general they just make an estimation.
    w00t

  6. #5
    Baby Seal Clubber ElPietro's Avatar
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    The answer is 42.
    Deadlifts are like women, they'll hurt you everytime, but they'll also make you a man. - Me

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    ElP is the smartest man in the world. - Gyno Rhino

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    I can picture in my mind a world without war, a world without hate. And I can picture us attacking that world, because they'd never expect it.

    Is there anything more beautiful than a beautiful, beautiful flamingo, flying across in front of a beautiful sunset? And he's carrying a beautiful rose in his beak, and also he's carrying a very beautiful painting with his feet. And also, you're drunk.

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  7. #6
    el imposible ectx's Avatar
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    but what is the question?

    *goes and chops up pedrito's brain to figure out the question to the answer the very smart mice requested*
    ecDoesIt

    "You're such a girl carbon. You're strong as hell, making wicked progress, and I post in your journal. WTF more could you want?"
    Anthony

    "When fascism comes to America, it will be wrapped in the flag and carrying the cross."
    - Sinclair Lewis

    My latest (and only) WBB article.

  8. #7
    Baby Seal Clubber ElPietro's Avatar
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    I do not have the time to explain things to those who cannot understand.
    Deadlifts are like women, they'll hurt you everytime, but they'll also make you a man. - Me

    Friends don't let friends do dumbell kickbacks. - Me

    ElP is the smartest man in the world. - Gyno Rhino

    A low voter turnout is an indication of fewer people going to the polls. -- Dan Quayle

    If do right, no can defense. -- Mr. Miyagi

    Deep Thoughts by Jack Handey:

    I can picture in my mind a world without war, a world without hate. And I can picture us attacking that world, because they'd never expect it.

    Is there anything more beautiful than a beautiful, beautiful flamingo, flying across in front of a beautiful sunset? And he's carrying a beautiful rose in his beak, and also he's carrying a very beautiful painting with his feet. And also, you're drunk.

    Current FFFA Enforcer

  9. #8
    Pot-bellied bean pole Big & Tall's Avatar
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    Yeah, 42 is about what I was thinking

    Gonepostal: That is what I figured on for a very rough calculation, but how is it even possible to make an estimation of an efficiency coefficient? How can we really get an internal measurement of calories burned? External work is easy enough to measure, but I have no idea how internal work could be measured.

    As an example of this, how have we arrived at the old standby of burning 3500 calories to lose a pound? One pound (448g) of animal fat, would contain 4032 calories if eaten (at 9 kcals/g). Does human adipose have a higher water content, or is there some measure of efficiency in there? i.e. by doing 3500 kcal of external work, one can reduce fat mass by 1 pound. This would give 3500/4032 = ~87% efficiency, which seems pretty high. Are existing data based on long term changes in fat mass based on measurements of external work?

    Okay, time for me to stop thinking before I hurt myself.
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  10. #9
    Teh kleptomaniac VasDeferens's Avatar
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    Quote Originally Posted by Big & Tall
    Yeah, 42 is about what I was thinking

    6 X 9 = 42

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