When David Walliams began his gruelling 120-mile journey along the Thames, perhaps he wasn't aware of just how much he would suffer.
Just a few hours into his eight-day swim, the comedian suffered his first setback.
He was forced to put on a wetsuit after his skin turned blue – a sign of hypothermia.
The Little Britain star then came down with "Thames tummy" after swallowing water full of bacteria.
He continued on his journey though despite bouts of vomitting and diarrhoea.
And now, since completing the Herculean task it has been revealed that he has torn a disk in his back and is still suffering from the bug.
A Comic Relief spokeswoman said:
"We understand David has contracted a bug that has caused a stomach upset.
"He is being treated for this and has been advised by medical professionals that it is not serious and that he will soon be back to full health. David has not been tested for Weil's disease."
David raised over £1 million for Sport Relief.
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