The TV presenter, 46, went from Edinburgh to London though a combination of cycling, running and swimming and admitted there were times during the punishing challenge she didn’t know if she would make it.
Speaking to a UK magazine, Davina said: “About five or six hours into the first day, I was battling with horrific winds. I got the beginnings of hypothermia.
“They had to get me into a parked car to warm me up, and I just cried non-stop for 20 minutes. I just thought, ‘How on earth am I going to do another six days of this?’”
But she did. She continued for the rest of the 130-miles set for the first day and ended up at the Lake District. By day three, in Lake Windermere, Davina was getting ready to start the swim, despite her fear of swimming in open water.
She said: “I was genuinely quite frightened during those last 15 minutes in the water. I didn’t pass out I just collapsed. I was so cold, I couldn’t move.”
Just ninety minutes later she was back on her bike and heading towards London.
The last day of her challenge saw her run over 27 miles and she said: “That last day I was at such a low. I’d lost it. I was crying non-stop. I ran past Buckingham Palace and I saw the Queen was there and I cried.
“I sobbed all the way down the Mall. I was just carried along by people.”
But despite everything, Davina made it to the end of her challenge. “It has definitely changed me,” she said. “I now know that I am capable of so much more than I ever thought I was. Every time I thought I’d got nothing left – more was in me.”