Tai chi is the middle way - you should never push yourself to extremes. If it hurts, stop doing it. Tai chi shouldn't hurt, if you're doing it correctly. If you feel tired, have a rest. It's ok to have time out - you can always start again, when you feel up to it.

When I started tai chi, I had been a couch potato for many years and was extremely unfit. Everything was an effort, especially as I had put on weight through inactivity and unhealthy eating. So I had less muscles to move around more of me;)

A *little* exercise every day (5-15 mins), in between tai chi sessions was quite enough for me back then. However, over time, I gradually got fitter, so that nowadays I can do several hours practice every day. I don't do this to feel virtuous about doing exercise, but because there are so many interesting tai chi things to try out - so much more than I had at first imagined from seeing people do it on TV.

The key to improving is gradual change. Slowly and gently, your body will accustom itself to your new practising, a lttle bit at a time, until you will surprise yourself one day with how much you can do. It's really nice to have that feeling of being able to do more and cope more. Persistence is the secret to progress in tai chi, as in most things!