What makes Usain Bolt’s muscles make him run as fast as he does?

Question: What makes Usain Bolt's muscles make him run as fast as he does?
- Keywords:
  muscle,
  run,
  usain bolt
Asked by hanzhodges to Lucy on 9 Nov 2016.
- Lucy Oldacre-Bartley answered on 9 Nov 2016:
  
  Usain bolt probably has a lot of fast twitch fibres, these are glycolitic and are useful for explosions of power and strength in the muscle. It is likely that Mo Farah for example has the opposite and has a lot of slow twitch fibres which allow him to run for longer.

Question: What makes Usain Bolt's muscles make him run as fast as he does?