Hardee was ahead after seven events and going into the final 1, 500m he was so comfortable that he could afford to clock a time about six seconds outside his personal best and still capture the title.

BBC: Walker storms to 400m hurdle gold

Travellers on long-haul flights, for example to California, which is eight hours behind UK time, take about a week to recover as the body clock can only adjust by one hour a day, he said.

BBC: Body clock reset clue discovered