The Challenge

In June 2015, Alex Smith completed a long distance triathlon - a 3.8km swim, 180km bike ride and 42km run - known as the toughest single day challenge you can undertake, carrying his 40kg disabled son the whole way. An epic achievement for his son, who is dying from a fatal muscle wasting disease: Duchenne muscular dystrophy.

• Peter WilliamsDirector

• Kay DaviesSelf
• Alex SmithSelf
• Donna SmithSelf
• Harrison SmithSelf