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Medical Human physical limits

  1. Jun 20, 2009 #1

    Mentallic

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    I was reading on the net about 800m distance running to try and improve myself in the event, and then happened to come across this ~
    Yes I know this is common sense and again backed up by medical science's experiments on lactic acid build-up and also since the professionals are far from completely sprinting the entire 800m leg.

    However, I had also heard (quote unsourced) that many years ago (probably 50+) it was said that the 4 minute mile is physically unbreakable. The current world record in that event is 3:43.

    So what I'm trying to say is, it is evident that with better technological advancements in athlete training they are now able to vastly outdo the athletes 100 years ago. Does this mean it may some day be possible to sprint the entire 800m? And thus achieve what wikipedia is calling 'impossible'?
     
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  3. Jun 20, 2009 #2

    Astronuc

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    The speed at which the leg muscles move is determined by the metabolic rate in the muscle tissue. There is a finite capacity.

    The record for the 400 m is held by Michael Johnson, with a time of 43.18 seconds, the record for the 800 m is by Wilson Kipketer at a time of 101.11 sec in Colognon e 24 August 1997.

    http://en.wikipedia.org/wiki/400_metres#Top_all-time_athletes_-_men
    http://en.wikipedia.org/wiki/800_metres#Records
    http://en.wikipedia.org/wiki/Mile_run_world_record_progression

    The records for various races seem to have reached a saturation limit or asymptote. The speeds increased with techique and training, and perhaps physiological development, but we now seem to have reached physiological limits.
     
  4. Jun 20, 2009 #3

    Mentallic

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    But what I'm thinking is that these limits can be broken through, or at least the limits themselves are extended due to technological enhancements. e.g. new aerodynamic and muscle-supporting clothing, new shoes etc. (not counting drugs).

    Correspondingly, the racing cars had gone through a similar experience. Now I know a car isn't biological, and of course much more susceptible to become better through tech advancements, but I think it follows the same structure. It was said (again, unsourced quote) that the racing cars had a limit at the speeds they could round a bend due to traction issues. That limit has been vastly surpassed simply due to the redesign of the car's wheels and weight (carbon fibre allowed for lighter weight) and possibly other factors.

    Couldn't it be possible that such redesigns can be made to enhance the athlete's limitations? But of course still staying within the guidelines of what is a legitimate enhancement i.e. nothing ridiculous like pogo-stick like shoes.
     
  5. Jun 21, 2009 #4

    Astronuc

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    I'm not sure that one would want to go too much faster, i.e., movement of the legs. But perhaps if one could store more energy in the shoes or support hose/pants, and recover more force per stride. We'd probably have to start banking the curves, which has been done for some tracks.

    There's almost no limit to the energy and forces that can be applied to a vehicle, but there is certainly an limit to what the human body can endure.

    One could bank a trank to vertical, but how practical would that be. People already race planes, and presumably one could race at supersonic speeds.
     
  6. Jun 22, 2009 #5

    Mentallic

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    I doubt this would be allowed. If we could theoretically harness other forms of energy release (I'm imagining artificially placed chemical reactions charging us internally or externally) then there should also be no limit to what a human can do. It would just depend on the amount of energy that can be released and harnessed.

    Yes this would be the main way to increase the possible limits of the athlete. Imagine such gear that is so aerodynamically sound it begins to approach the same effects of running through a vacuum. No air resistance, much higher limits.

    Well, the top speeds achieved are 40km/h and this has been achieved for a couple of seconds at most by the best sprinters. Even at those speeds there are no problems with traction as can be seen in the 200m sprints. If they were to bank the tracks, it's just an attempt to create the same effect as running in a continuous straight line. Not so necessary in my opinion.

    Yes thats true and this is what I meant by:
    But who is to say that the limit the human body (mind you, with the aid of technology) can endure makes the idea of sprinting 800m absurd? As far as the present athletes have advanced and surpassed their ancestors, if this is to be kept up, I wouldn't be making any assumptions on the human's limits.

    I have no clue how this is relevant :tongue:
     
  7. Jun 22, 2009 #6

    Andy Resnick

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    There are some physiological limits to how much power a muscle can produce.

    Skeletal muscle has enough ATP on hand (5 umol per g muscle) to last about 10 contractions. After that, the muscle must regenerate ATP, which ultimately sets a limit on when exhaustion sets in:

    1) dephosphorylation of creatine phosphate is the most rapid form of ATP regeneration, and will supply power for 10-20 seconds (a 100 or 200 m race)
    2) On a slower timescale is anaerobic glycolysis
    3) even slower is aerobic oxidation of glucose

    The first two processes, combined, will provide about 40 seconds of effort before the production of lactic acid leads to fatigue. The 'endurance limit' of aerobic activity is about 370 W.
     
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