Start any movement practice slowly and build up steadily. If you are following these videos and find some of the movements are difficult, try adapting it to your needs. The key is to feel challenged, but confident!
Pick something you think you will enjoy, as you are more likely to repeat it. Exercise doesn't need to give you a 'buzz' or make you sweat - movement can be relaxing and restorative too.
Muscle soreness is normal following an activity you haven't done for a while. If this happens, keep moving gently, but give yourself a chance to recover before doing another challenging set of exercises.
Gentle Chair Yoga Routine This is from a pain service in Canada.
Chair based exercise These gentle exercises can be helpful to maintain movement during a flare up.
Gentle yoga for chronic pain Mat based Yoga with Adrienne
Overcome pain with gentle yoga - cost involved.
Blogs and information on exercising:
Exercising with persistent pain - a blog from Ann who has persistent pain and is a physiotherapist