Why are we competitive? Is it a natural instinct? Should we nurture competition in our children so they learn that victory is the ultimate goal and that only the fittest survive? Or do we over emphasise the importance of competition at the expense of all else?

Jo Fidgen explores why we are so reliant on competition and what it means for our future success. She finds out how hormones affect our competitive behaviour and whether men are always more competitive than women.

(Photo: two hurdlers competing against each other at the Shanghai Stadium in China, Credit: Getty Images)