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CLIP 13435

Why can’t I run fast?

Why can’t I run fast?

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Key Info
  • Why can’t I run fast?
  • Duration: 5:14
  • Presenter Greg Foot investigates whether humans will be able to run faster and continue to break world records, or if there is a limit to human performance. Greg explains that running involves exerting a force against the ground which in turn exerts a counter-force on the human body. The greater the force exerted by the leg muscles, the faster a sprinter can run. He demonstrates the force exerted by running over a pressure pad and explains the force is measured in Newtons. A top athlete can exert a force of four times their body weight but this force is limited by our genes. Greg explains the difference between slow-twitch and fast-twitch muscle fibres and why sprinters need genes that ensure they have more fast-twitch fibres than most other people. He then explains why four legs are better than two legs and investigates if having longer legs would enable us to run faster. First broadcast on BBC Learning Zone and BBC3 in March 2012 as part of the series The Secrets of Everything.
  • Subject:



    Phys: Forces - Motion

  • Keywords: Sprinter, force, counter-force, Newtons, muscles, pressure-pad, genes, slow-twitch fibres, fast-twitch fibres, pro-jump stilts, TheSecretsofEverything
Ideas for use in class
  • Useful when looking at: human biology and how muscles work. Human biology and genetics of inheritance. Physics concerning how forces work. Students can investigate force and counter-force when a force is applied to an object in relation to Newton’s laws. Cross curricular links – The history of famous scientists i.e. Sir Isaac Newton. Contains examples of ‘How Science Works’.
Background details
  • Clip language : English
  • Aspect ratio : 16x9

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