Jamie will be running across Canada during part of their winter, so will encounter Arctic temperatures he has never experienced before.
We took him to Gloucerstershire University's Sport & Exercise Laboratory where they have a chamber in which the temperature can be lowered to minus 20C.
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The actor who plays The Incredible Hulk visited Patchway Police Station in Bristol today - Lou Ferrigno was in the city for his new film.
Bristol City Council is set to debate its controversial 20mph speed limits - after thousands signed a petition to calling them 'ludicrous'.
A runner from Bristol is about to embark upon a marathon challenge around the UK, running 26 miles every day for more than a year.