London 2012: Asha Philip on her 'rollercoaster' journey back to fitness

It has taken almost four years for 21-year-old British sprinter Asha Philip to work her way back to competition after a serious knee injury.

Philip, who is Britain's fastest woman indoors this year, talks to BBC Sport's Jessica Creighton about being the woman to beat ahead of the Olympic trials, 22-24 June.