BBC Breakfast presenter Susanna Reid has vowed not to run the London Marathon again because the training – or lack of it – is making her grumpy.

The TV presenter, 42, is taking part in the gruelling event with BBC newsreader Sophie Raworth and Breakfast presenter turned Radio 4 host Sian Williams.

Susanna, who completed the marathon last year in five hours 12 minutes, told Radio Times before the Boston Marathon bombings: “I’m probably the slowest of all the BBC runners… Second time round, I want something with a four, even if it’s four hours 58 minutes, or four hours 59 minutes 59 seconds, I’ll be happy.

“And then I’m not going to do it again.”

She said that running in two consecutive years was ‘a bit crazy’ because of all the training.

“I find it quite stressful when you haven’t done what your schedule says you need to do… the weather has made it much tougher because you have to really motivate yourself to get out the door when it’s so cold – and I’ve struggled,” she added. “Then I feel guilty and grumpy because I’ve missed runs.”

Susanna added: “I’d like to be able to say that I get runner’s bliss and that it’s wonderful. Sadly I can’t. Sometimes I’ll be out there thinking, ‘What on earth am I doing?’ The only good feeling I get from running is when I’ve finished: ‘Oh, it’s over, thank goodness for that’.”

Meanwhile, former Breakfast presenter Sian will be hoping to get over her fears after last time she attempted a marathon she almost died from drinking too much water.

After swearing ‘never to run that far again’, she decided to run the marathon for cancer charity Macmillan following the death of her mother from terminal cancer.

She said of her horrendous day in New York in 2001: “My last memory is crossing the finishing line and having a headache. Various things started to shut down: I couldn’t hear, then I couldn’t see, then my legs went and I couldn’t talk. Two days later I woke up in a New York hospital thinking, ‘Where am I?’ It was incredibly scary.”