SHE has been left exhausted almost to the point of collapse by a swim in the freezing waters of the Lake District and has run her heart out to raise money for charity.

Last night, TV presenter Davina McCall could barely believe that she had succeeded in completing a gruelling 500-mile journey from Edinburgh to London.

The presenter crossed the finish line outside the Tate Modern gallery in London after running through the UK capital to conclude the final leg of her arduous physical challenge for Sport Relief.

Her efforts in the challenge, sponsored by BT Sport, have so far raised £760,000.

McCall, 46, ran a full marathon distance to round off seven days of running, cycling and swimming for charity, and was watched by a crowd of 100 on the last lap.

She said: "I can't believe it was me. Thank you to everybody who has donated - that is why I did it - the team that got me here, they carried me through the threshold.

"My kids and my husband were amazing."

She joked: "I have got to stop crying!"

McCall was greeted by her children and her husband, Matthew Robertson, just before the finish line. He gave her wedding ring back to her, which he had been looking after during her journey.

McCall has won over the public with her resilience over the past few days, with TV viewers seeing her sobbing and barely able to enter the water during a 1.5-mile swim across Windermere on Monday.

Her body was limp by the time she was dragged from the lake at the other side and she then had to continue her journey in the saddle for the rest of that day.

The TV star has also been battling with the pain of being in the saddle for so long, as well as struggling to take in enough nutrition after losing her appetite despite needing to take on board at least 8000 calories daily to tackle the challenge.