Conor D'Arcy has always loved sport – everything from soccer to swim-ming. He has even done a sky dive and works in a job where he is on his feet, moving around fast for up to 10 hours a day.
At the age of 20, Conor does not fit the popular image of someone who has arthritis.
"People believe it only hits retired people and old labradors," says Conor, a barman in Dublin's Shelbourne Hotel.
Arthritis is the single biggest cause of disability in Ireland, affecting almost one million people from newborn babies through to the elderly. Conor was first diagnosed at the age of seven.
There is still a common view that people with the condition should not move around, but doctors now advise that patients should take plenty of exercise.
That was the key message of Arthritis Ireland's recently launched campaign, 'Moving is the Best Medicine'.
"I have found that doing lots of exercise has benefited me because it strengthens the muscles and that is good," says the Dubliner. "If you don't keep active, your joints tend to stiffen up."
Conor, whose family comes from Beaumont in Dublin, was in first class at primary school when he noticed pains in his legs.
"At first when I went to the doctor they thought I had growing pains," he says. "I had to go two or three times and then I was admitted to hospital."
He had to spend a month in Temple Street Children's Hospital before he was finally diagnosed with juvenile arthritis.
It is estimated that 1,000 children in Ireland have the condition. Most can continue to lead an active life if they are given proper care.
"I was a rare case in that I had full-body arthritis," says Conor. "It affected all my joints and at times I was in a lot of pain. The worst pains were in my hips, knees and ankles."
Conor believes that his diagnosis and the treatment that followed were probably more stressful for his parents than they were for him.
"I suppose when you are a child you don't know anything different, and you just get on with it, whereas my mum and dad had to worry about me."
When he was a boy, Conor went for hydrotherapy – special exercises in a swimming pool – at the Central Remedial Clinic in Clontarf. "I found that was a great help for relieving the pain." Conor has spent many weeks in various hospitals, and travelled to Great Ormond Street in London regularly for treatment. He played for Artane Beaumont Football Club until the age of 18.
The effects of his arthritis can fluctuate wildly.
"It comes and goes. One morning you could be in excruciating pain, the next you could be out playing a 90-minute football match."