Resources:
http://www.biography.com/people/usain-bolt-20702091
http://www.justrun.org/JR_for_kids/fitness_and_running_tips_for_kids/showsection367a.htm
http://www.sports-reference.com/olympics/athletes/re/derek-redmond-1.html
http://www.nhs.uk/Livewell/c25k/Pages/running-injuries.aspxhttp://www.infoplease.com/biography/var/usainbolt.html