Davina McCall revealed she woke up in tears this morning as the gruelling back to back feats of endurance take their toll during her 500-mile challenge.

The presenter had to contend with howling winds yesterday which meant the latest cycling leg of her journey yesterday took two hours longer than planned and was like going "through treacle".

The force of the winds she faced between the Peak District and Birmingham were so strong she had to actually pedal downhill and left her spilling with anger, she said this morning.

She told BBC Breakfast: "It was awful, misery yesterday, like cycling through treacle.

"I was just going a little bit mad - The Mistral in France sends people 'aaaargh' - I felt like yesterday I was talking to myself, I had to chivvy myself along, I was talking to my sister, saying 'this is what the Mistral is like in France, it's driving me mad'."

During one of her scheduled stops en route, she found herself telling the support team: "I'm really angry, I'm just really angry with the wind."

The presenter is undertaking the BT Sport Relief Challenge: Davina - Beyond Breaking Point, travelling from Edinburgh to London under her own steam by cycling, running and swimming.

McCall, 46, said she was in tears as she awoke today but had a visit from comedian friend Mel Giedroyc first thing who brightened her day.

"I cried this morning, I opened my eyes and started crying and then there was a little knock at the door and Mel walks in - and I was laughing," she said.

The severe weather has also meant that day's stage of the journey is still slightly uncertain because of the flooding in the Thames Valley.

She is due to cycle 112 miles to Windsor but areas close by, such as Datchet, have sizeable areas underwater.

"We're not quite sure how it's going to pan out because obviously we are trying to get to Windsor and ... the country is under deluge of tons and tons of water.

"Our route was down by the Thames so we're just going to have to look at the route a bit today. Sort of take each section as it comes and try to get to Windsor. We're going to get to Windsor."

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 Lake Windermere on Monday morning. Her body was limp by the time she was dragged from the water 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 8,000 calories daily to tackle the challenge.

Tomorrow she is due to round off her seven-day journey with a marathon distance which will bring her to the finish at Tate Modern in London.

McCall said it was the thought of being reunited with her children which was keeping her going.