Whitehead is a natural marathon runner but turned to sprinting because there was no marathon for him to compete in at the London 2012 Paralympics. He not only stormed home to 200m gold but also to a world record.
This charity challenge is also a million pound fundraising quest as he hopes to raise at least that amount - through donations and sponsorship of people who want to run alongside him - for the charities Sarcoma UK and Scope.
More top news
Michael Fallon has received reassurances from his US counterpart that security ties with Britain will "endure" following a vote for Brexit.
On Friday, police said it appeared the girl had shot herself in the face with the weapon.
The showers will be slow-moving, heavy and thundery at times, particularly in central and eastern areas.