Charity fundraisers often risk their lives to capture the public's imagination. But are extreme challenges worth the pain for the sums such efforts raise?
"I am not an attention seeker - if I did not fundraise I would go mental with grief."
This is the emphatic response from marathon fundraiser, "Run Geordie Run" - aka Mark Allison, to a suggestion that ego may partly spur him on to carry out his epic cross-continent runs.
His most recent was across the Australian Outback when he raised £54,000.
The run took months to prepare and was so gruelling he almost gave up. So was it worth it?
He admits the three-month challenge was "overwhelmingly hard" and he will be lucky if all sensation returns to his feet by the autumn.
But he is adamant. "It was absolutely worth it," he insists despite the legacy of damage to his feet.
The list is a long one - the fatty balls of tissue in his soles have been displaced, his tendons and bones are damaged and there are also pockets of painful fluid in his ankles.
He also had to contend with a limp for months.
In fact, if it was not for a local podiatrist giving him hours of free treatment a week he would have a medical bill of thousands of pounds.