Katier Clark is perched high aboard Racing Demon as she prepares to take the totesport Cheltenham Gold Cup contender out for his daily exercise.

The eight-year-old gelding is very much on his toes at Henrietta Knight's West Lockinge stables, near Wantage.

And his rider takes a firm hold before directing him out on to the country roads to stretch his well-tuned muscles.

It's a chilly morning as a brisk, icy breeze whips across the all-weather gallop on the south Oxfordshire downs.

A red kite hovers overhead before Clark and Racing Demon appear in the distance at the foot of the steady incline, and set off around the railed-off one-mile loop.

Moments later, horse and rider sweep past in perfect harmony before pulling up on the crest of the hill.

Watching from his Range Rover, Terry Biddlecombe, Knight's husband, is there to greet them, and check that everything has gone according to plan.

It's a scene that will be repeated each day many times over at stables up and down the country.

But the remarkable thing in this case is that Clark is able to carry out the role at all.

In November 2005, the 28-year-old's world was turned upside down when she was diagnosed with cancer.

Her life for the next 15 months was spent between trips to - and spells - in Oxford's John Radcliffe and Churchill hospitals, with a visit to London's Harefield hospital thrown in for good measure.

"To start off with I just thought it was a bad back," says Clark as she sits at the table in the conservatory back at Knight's farmhouse.

"When I eventually had a scan they found I had a huge tumour in my chest.

"I was terrified. You are devastated - it is like your whole world stops.

"I had to tell my parents (John and Elaine) which I found really hard. You are angry and ask 'why does it happen to me'.

"I was taken straight into hospital and the scans diagnosed lymph cancer. I was in hospital for nine weeks and everything they tried, nothing went right.

"Then they diagnosed aggressive Hodgkin's lymphoma, which they thought I had had for three years.

"They found it because the tumour got to such a size, and I had to have chemotherapy every fortnight for eight months, and that wiped me out."

But all the time the thought of returning to work with Knight's horses spurred her on.

The trainer would take her racing when the horses she used to look after, including her old favourite Easter Present, ran.

"When my horses ran Hen was brilliant. She would take me in the car to the races. I was so weak and very poorly," says Clark, who joined Knight's yard in 2001 following a spell at the late Geoff Hubbard's and three years working at her local riding school in Suffolk.

"I got in the car and felt I shouldn't be going. I felt so ill, but I wanted to be with my horses and see them run."

She did odd jobs in Knight's office, before returning to work in late 2006 only to then suffer a massive setback.

"I must have been back at work for a couple of months when I went back for a routine check and scan and was told that I had relapsed," she says.

The tumour had returned and she was prescribed a longer, stronger course of chemotherapy.

Doctors decided that she should undergo stem-cell treatment, but before that could take place, at Christmas time, she was diagnosed with depression.

"I had coped for a year, and got through it," she says. "But then everything became too much. I collapsed and couldn't deal with it any more.

"They were really dark days. I would wake up in the morning and think how many hours stretched ahead, and I didn't know how I was going to get through them.

"No matter what anyone said nothing seemed to help. I was put on medication and my parents, bless them, would come up and take me back to Suffolk to try and put me in a different situation.

"But you just lock yourself away in a different world and don't let anyone in."

Stem-cell treatment followed in January last year when Clark spent a month in isolation in hospital.

A course of radiotherapy followed, which saw Clark going to hospital in Oxford each day for around a month.

But the desire to work with Knight's horses continued to burn inside her, and she again started to turn the corner.

"They are like a medicine themselves - nothing like the doctor can prescribe," she says. "It is just what you want to be doing.

"It isn't the easiest job in the world - there are early mornings and it is freezing cold. It isn't like being in an office.

"But you do it for the love of the game and love of the animals and the pleasure they give you.

"When I tell my doctor I have gone back to work he is still shocked with what I am doing, but they are not going to stop me. As long as I can do it I will do."

Appreciating that Clark's love of horses was driving her on, Knight let her lead up Aztec Warrior at the Cheltenham Festival last March for the Jewson Novices' Handicap Chase.

"He is one of my horses," says Clark. "He is a big horse, but he was an absolute poppet.

"I think he led me round and helped me, but it spurred me on and made me think I will get back and I will get better."

It was only in June last year that Clark returned to work full-time - and Knight gave her a huge lift by entrusting her with looking after stable star Racing Demon.

"I love him to bits," she says. "He is cheeky. He never sits still - he is like a hyperactive kid. When he is in his box, he gives you a playful nip.

"He likes to show he is the boss, but there is no nastiness in him at all. He is a real character."

Clark returns to hospital every two months, and is now described as being in 'good partial remission'.

"I have a scan to see there is no abnormal activity and that it has not spread anywhere else, so they are all quite pleased with me," she says.

"If you had told me a year ago I would be riding Racing Demon out every day and looking forward to leading him up in the Gold Cup I would have said you were stupid.

"I am just so happy to be back to normal."

And she says that without the help she's received she doesn't think she would have made it back - giving special mention to her brother, Ian, and his wife, Claire.

"I can't say enough about my friends and family and the yard and all the owners," she says.

"Everyone has just helped so much. I just don't think it would be possible without them."

Now her remarkable courage in the face of such adversity has been recognised by those in the sport.

At the fourth annual Stud and Stable Staff Awards at London's Café Royal, she received the Special/Merit Hero prize - for those who have shown bravery, courage or outstanding achievement in the course of their work - from three-times champion jump jockey Richard Dunwoody.

"It was so exciting," she says. "I was up against one girl (Katie Whyte), who had been so brave, and Jerry (Walsh), who has done so much for others.

"When they called my name out out to say I had won I was speechless. I was just completely shocked. It is just thanks to Hen who nominated me."

Clark received separate cheques of £3,000 for herself and her West Lockinge colleagues.

"I was really chuffed about that because they raised money to help me when I was struggling, and it is really nice to give them something back," she says.

And now she can't wait to lead up Racing Demon in Friday's Gold Cup when he will face reigning champion Kauto Star and his big rival Denman.

"Every stable lad and lass wants to lead a horse up at the Grand National or the Gold Cup," she says.

"It is an absolute dream. I have been involved with the yard with Best Mate winning three Gold Cups, but taking your own horse to the Gold Cup and leading him up is really exciting.

"Kauto Star and Denman are absolute machines. They are amazing horses the pair of them. I am a bit of a Denman fan, but nothing in racing is a certainty.

"I know everyone says it is the wrong way round as he jumps right-handed, but if he can keep it together and keep his cool he has a good outside chance."

With those thoughts fresh in her mind, Clark is off to ride out Aztec Warrior. Happy to be normal, as she says.

But in the eyes of a the racing world, a special stable groom.