Sara Cox has confessed that she hasn't been "sleeping well" after completing her arduous five-day run for Children in Need. Sara, the host of BBC Radio 2's drivetime show, recently finished a 135-mile run over five days — the equivalent of five marathons — raising more than £11 million for the charity.

She started her mammoth journey in Kielder Forest, Northumberland, and ended it in Pudsey, West Yorkshire, on Friday, November 14, but admitted that it was the "hardest thing" she’d ever done after she crossed the finish line.

Since completing the distance, Sarais apparently still struggling with the after-effects as her body continues to recover from the gruelling challenge. In fact, the 50-year-old presenter was "shocked by how much it hurt".

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Sara told The Times: "Since finishing the Children in Need challenge, it's been really tough. I am not sleeping well. I am so stiff and sore, especially my knees and shins, because they took a pounding."

In a further admission, Sara explained how walking her dogswas a difficult task: "Normally I am so fast, but I took the dogs out this morning and I was hobbling. They were like, 'What is wrong with you?'

She added: "I thought I had a high pain threshold, but I was shocked by how much it hurt. They kept promising me it would be undulating. This was not undulating; this was steep hills. Going down was the killer. I had to go backwards because each step was agony."

Over the course of her journey, reportedly the longest ever undertaken by Radio 2(co-hosts Paddy McGuinness and Vernon Kay undertook their own challenges in previous years), Sara received messages of support.

One such message, from the future king Prince William, was played by Scott Mills on his Radio 2 breakfast show. In his message, William offered his "massive congratulations", reports The Guardian.

He said: "You're so nearly there – just a little bit further and I know the people of Pudsey will all come out and welcome you with huge open arms, big hugs and, hopefully, lots of your favourite crumpets.

"Keep going – you've done fantastically well and the nation's so proud of you."

In the aftermath, Sarasaid she'd "never known pain like it", but had also never had eye contact with "so many amazing women", who she explained had "powered" her through the feat.

Sara, who started on Monday, November 10, carried a Pudsey Bear backpack (Pudsey being the charity's symbol) and spanned four counties — Northumberland, County Durham, North Yorkshire and West Yorkshire — during her journey.

As of November 20, Sara had raisedan incredible £11,501,637, according to The Mail, as she continued to be inundated with generous donations following the airing of Sara Cox: Every Step of the Way last week.