Tackling a marathon is a real undertaking.

But imagine if you have just 12 weeks preparation and also have to re-learn how to walk.

That’s what paralysed former four-star event rider Claire Lomas has in store between now and 22 April, when she will walk the London Marathon in a special robotic suit.

“The training is physically very tiring but mentally exhausting.

I thought nothing could be as challenging as riding round Burghley five years ago, but this is much harder,” said Claire.

Claire is one of just two people in the UK being trained to use the Re-Walk suit – a powered exoskeleton that allows the wearer to walk with crutches.

And now she’s in a race with her year-old daughter Maisie to see who will be walking first.

“I’m going all out to beat her,” joked Claire. “I’ve had four sessions and managed to put 27 steps together in the last one. I don’t know how many lots of 27 steps there are a marathon…”

Claire thinks it will take her around two weeks to complete the 26-mile course.

She has been confined to a wheelchair since being injured in a fall at Osberton Horse Trials in 2007.

But she is determined to walk again, and although she will undertake the marathon in the training suit, fundraisers have helped her raise the £35,000 to buy the world’s first personal suit – due to be delivered this summer.

The Re-Walk is designed by Israeli company Argo Medical Technologies and distributed in the UK and Ireland by Yorkshire-based Cyclone Technology.

Dave Hawking of Cyclone Technology told H&H: “It’s going to be a huge challenge for Claire.

“I’d rather she had decided to do a 5K, but is anyone is going to complete the marathon in this suit it will be Claire. Her mental attitude is amazing.”

Claire has set herself a target of raising at least £50,000, for Spinal Research with the challenge.

Robin Plowman of the charity said: “It is an incredibly physical challenge for someone with a spinal injury – Claire is a real inspiration.”

To sponsor Claire, go to www.justgiving.com/Claire-Lomas or contact her at clairesfund@hotmail.co.uk.