Q: I'm a 41-year-old man and have been keen on sport all my life. However, I've suffered discomfort in my knees since my late teens but always run or played through the pain. Two years ago I was diagnosed with osteoarthritis in both knees. Now my doctor recommends I stop any high-impact sport to prevent having knee-replacement surgery in the next 15 years. So I've stopped running, playing rugby and going to the gym - and I've struggled to find activities that deliver the same competitive buzz. My fitness has deteriorated and I've put on weight. Can you suggest any activities which will give me the same kick without pain? And is there something I can do which will postpone surgery for as long as possible?

The consultant

Osteoarthritis is a disease that happens when the connective tissue between your joints starts to degenerate and the bone grows back thicker to compensate. There are many causes: it can run in families, and repetitive high-impact loads (from certain jobs or elite sports) put joints at risk. A normal level of sport shouldn't bring it on; there is, however, a link with injury. Many over the age of 55 have some form of osteoarthritis. At 41 you are young, but you can avoid surgery. The most important thing is to strengthen the big, supportive thigh muscles above your knees, the quadriceps. This has been proven to reduce pain. The easiest way to do it is with a simple leg lift - there's a diagram in the booklet Osteoarthritis of the Knee at www.arc.org.uk. You should feel an improvement in four to six weeks. Also, make sure all your shoes have shock-absorbing soles and good arch support.
· Philip Conaghan is professor of musculoskeletal medicine at Leeds University and spokesperson for the Arthritis Research Campaign (0870 850 5000)

The fellow sufferer

I developed osteoarthritis in my knees in my mid-forties. I was shocked to be diagnosed at such a young age. Now I work for Arthritis Care, and 60 per cent of our calls are from people aged 20-65. It's frustrating: I've always been an active person and I hate the way the pain slows me down. Sometimes it feels like a red-hot needle being grated around inside my knee joint. But I want to avoid surgery, and I find the key to managing the pain is exercise. I have a static bike in my bedroom I use for 30 minutes every evening. When the pain is bad, paracetamol tablets or ibuprofen gel work very well - you can buy both in pharmacies. There's also been good research on creams that contain capsaicin, the active ingredient in chilli peppers. This helps block the 'pain' message in your nerves by replacing it with 'heat'. Osteoarthritis doesn't have to mean the end of being active: you just need to manage it properly.
· Jo Cumming is helplines manager for Arthritis Care (www.arthritiscare.org.uk). For the free booklet Living with Osteoarthritis, or for free advice, call 0808 800 4050

The physiotherapist

Your osteoarthritis seems unfair - there will be other 41-year-olds out there who've played rugby or run for years with no problem. But that doesn't mean you should stop exercising. The latest evidence shows that the right kind of physical activity reduces pain, protects against further damage and is vital for keeping off excess weight. You may not be able to play the same kind of competitive sports, but the trick is to build up slowly with low-impact activities. Start with walking a short distance daily, building up to 30 minutes. Once you're feeling confident, move on to swimming to increase strength without strain. If either of these activities causes pain, apply a hot-water bottle or a bag of frozen peas wrapped in a towel for 10 minutes, then try again. You may not be able to play the same kind of contact sports, but for the competitive buzz try to think of non-contact, low-impact activities, like sailing or golf (use a trolley).
· Mike Hurley is professor of physiotherapy at King's College, London

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