By Jane Elliott
Health reporter, BBC News
Faye Goodwin loves to keep fit. Since childhood, she has enjoyed trampolining, dancing, cycling and swimming.
Faye knows exercise is important
But as the years go by Faye, who has cystic fibrosis (CF), finds she can do less and less.
She is on the list for a double lung and heart transplant and knows it is vital she keeps as fit as possible to maximise its success rates.
But as her lung function deteriorates - she currently has only 15% of the lung capacity she should have - exercise takes more and more effort.
This year she had to give up her cycling; she now finds walking up the stairs unaided a struggle.
The only sport she can now do is swimming. But as she is on oxygen 24 hours a day, she needs to tow an oxygen tank behind her in the pool.
Faye is determined, however, to continue her weekly routine.
"I really enjoy swimming. Just getting in the water and splashing about is enough for me.
"When I had to go on to oxygen about three years ago, I really wanted to keep on swimming and we could not work out how to do it.
"We knew we had to keep the oxygen tank dry and we tried everything from packing it in plastic bags to rubber rings. Now I swim along and it floats behind me in a rubber dinghy.
"I just wanted to be able to swim like everyone else. I know I am disabled, but I don't think of myself that way.
"I know how important it is to keep fit. After all, my life depends on it.
"I need to be fit enough to fight off infection.
"When it comes to exercise my body is saying 'don't do it' but my head says 'you must get as fit as possible'."
CF is a genetic condition which causes chronic lung damage due to the build-up of excessive amounts of sticky mucus.
For most of her childhood Faye, aged 24, was well. She had her first chest infection in her last year in primary school and was hospitalised again in her last year of senior school after her lung collapsed.
Faye has been given an award for her courage
It was not until she was 21 that her problems really started, while she was on holiday in Spain.
"My breathing started to deteriorate and I went from being a well and healthy person to someone in a wheelchair.
"Because I was on holiday with a friend and her family, I did not want to spoil their holiday so I put on a brave face and just got on with it.
"When I got back I was having real difficulty breathing and was going purple in the face. I was put on oxygen at night and then had to go on it during the day as well."
When Faye, from Hornchurch, Essex, was put on the transplant list she was told she had about three years to live.
Two-and-a-half years later she is still waiting for a donor, but says she is refusing to give up hope.
"I do feel weaker and I know that I am getting worse, but I do try and forget about it most of the time.
"When I first went on the list I would jump out of my skin every time the phone went. I don't give up hope now, but I do try not to think about it all the time."
Faye recently won a courage award from the Cystic Fibrosis Trust.
A spokesperson from the trust reiterated the importance of regular exercise for patients like Faye.
"It acts as a form of physiotherapy, helping to keep the lungs clear, and also helps maintain physical fitness.
Chest X-ray of the lungs of a person with cystic fibrosis (CF)
"People with CF should be encouraged to take exercise and participate in sport.
"Swimming is an ideal exercise as it is also a hobby that Faye really enjoys."
Dr Lieske Kuitert, CF physician at Barts and the Royal London, said exercise was very beneficial to patients, helping them clear mucus from their lungs.
She said regular exercise also helped patients build up their stamina, helping make them as fit as possible.
"We do get our physiotherapists to fit regimes round the patients.
"Faye is fantastic because she tries to keep as fit as she can be. She has an amazing spirit and has done a lot better than expected, and that must in part be due to her regular exercise."