20 March 2012 Last updated at 10:42

London 2012: World Olympic Dreams in Rio

Matthew Pinsent travels to Rio - host city of the 2016 Olympics - to meet young athletes hoping to compete there, and at London 2012. He meets a young man whose father's death at the hands of drug lords spurred him to take up boxing.

Also, four brothers tell of their dreams of playing rugby at the Rio Olympics and a young judo fighter from the north of Brazil explains why it is not always best to listen to mum.