Thanks for asking the question. Ankylosing spondylitis is a chronic condition that has genetic origin. It is important to stay active and mobile. Do regular exercise, yoga, Pilates to help you with this. Regular stretching will also help. Taking painkillers is  important but take them as and when you need them. Medical management of the other conditions associated with AS is also equally important. There are times when the condition becomes worse and flares up and there are times when it is not too bad. Such is the nature of the disease. You may be in the flare up phase now. Any regular activity is worthwhile and in due course of time you will be able to run, but with limitations. There are no restrictions on food or sleeping posture. Make sure you use a firm mattress to support your back well. Dr Vinu Raj MBBS MRCS FRCS (Trauma&Orthopaedics) Consultant Orthopaedic Spinal Surgeon