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2 questions about muscle growth from a boilogical/evolutionary pov

  1. Mar 12, 2007 #1
    hey, i've always wondered this and couldn't find an answer for it:

    1) suppose you're a person who works out, and then you stop. how long does it take for your muscles to go "back to normal." and does this deterioration begin as soon as muscle repair after the workout has stopped (24-36 hours after workout), or does it take a few days/weeks for your body to stop maintaining that muscle?

    2) from an evolutionary standpoint, why is it that our bodies are told to build muscle only if we ingest food right after the workout/muscle damage.
    if you work out, you know that you are supposed to eat large amounts of protein and carbs right away after the work out, preferably before an hour has passed, or else you won't grow and the workout will be a waste.
    I don't understand how this would make sense from an evolutionary standpoint? ... if a caveman works hard for hours to hunt for food, why the small, one hour window of opportunity to reward him with muscle repair and growth?

  2. jcsd
  3. Mar 12, 2007 #2

    jim mcnamara

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    Staff: Mentor

    1. This isn't a one-line-answer-question. As you extend physical capability (it ain't just size of muscle, it's how the muscle "wiring" has changed, and how effective it is at doing work) muscles will do more work and be used in new ways, ways that were not part of the the "before resistance training" snapshot of activity for the muscle group.

    2. I'm not sure this statement is correct. It sounds more like an ad for a protein supplement. Protein does speed up mucle growth, but it is not the whole picture like those whey protein supplement companies would have you believe.

    If this topic really interests, you consider reading 'Paleolithic Prescription' by Eaton, Shostak & Conner. While the book emphasizes diet, it also deals with a lot more.
  4. Mar 12, 2007 #3
    true, I guess it could be a rumor started by protein-shake companies that has turned into an urban legend... but pretty much every place you read on weight lifting tells you to ingest high amounts of protein/carb before that magical one-hour window is up.... i've always thought it would make no sense for an animal to evolve with such a small window for muscle growth...
  5. Mar 12, 2007 #4

    jim mcnamara

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    Those drinks do impact muscle and weight gain to some degree. However, when being strong and fast meant not being eaten by the local pride of lions, there were no whey supplements.

    It's a little like the "perfect" plant fertilizers we've developed. They get max results more quickly than more "natural" means. And we've genetically altered plants to do netter with those fertilizers. Maybe we could do the same with humans, but other than cosmetic and impatience reasons I dunno what the real benefit would be. We might live or die on the presence of daily whey milk shakes in our diet :)
  6. Mar 12, 2007 #5


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    One question to ask yourself when considering things from an evolutionary point of view is what is the physiological basis for this? In other words, it's not part of normal physiology to grow giant muscles from normal amounts of work. What body builders are pushing their bodies to do has no particular evolutionary advantage (other than potentially mate selection), and involves growth of muscles to an extreme that one would not expect without pharmacological assistance.

    There is no "1 hour window" for eating protein to gain strength. Just doing the same activities day after day will develop enough muscle to do those activities. The type of extreme workouts that body builders go through would be considered a waste of energy from an ecological standpoint. It doesn't help acquire food, it doesn't help provide shelter, and it doesn't help chase down a mate and reproduce any faster.
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