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Bodies in motion…

  1. Nov 9, 2009 #1
    Why can’t a 300lb NFL lineman accelerate off the line and maintain equal speed with a 180lb wide receiver? I realize there is more mass to set in motion, but there is also a greater amount of muscle to move that mass. If the ratio of muscle to mass is the same in both men, shouldn’t speed be equal? Thanks.
  2. jcsd
  3. Nov 9, 2009 #2


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    Gold Member

    Because not all muscle works towards running speed.

    Having a lot of upper body strength might as well be like wearing a heavy backpack for a runner.
  4. Nov 9, 2009 #3


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    Staff: Mentor

    Is the ratio of muscle mass to body mass ever equal between a lineman and a wideout?

    I believe the answer to that is no, which answers your question.
  5. Nov 9, 2009 #4
    Well, no. The 300 lb lineman will not be able to keep up with the wide receiver because they both have the same lung capacity. Therefore, both players' muscles are receiving the same amount of oxygen. Thus although the heavier player can exert a greater force than the lighter player, he/she will have more difficulty maintaining a constant rate of acceleration and will tire out faster than the lighter player.
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