For World Olympic Dreams, Andy Akinwolere travels across Jamaica to find out what makes its athletes run so fast. He visits Bolt's former school, tests himself for the "speed gene" and buys some very special vegetables.

Bolt is the latest - and fastest - in a long line of sprinters from Jamaica who have left the opposition in their wake over the last few years. There are many theories to explain the phenomenon - some scientific and some less so. In this programme, Blue Peter presenter Andy Akinwolere takes a jog across the island to put those theories to the test. Show less