Ok this isn't so much a coaching tip and more of a bit of advice for your well being. Over the years I have seen many cases of tennis elbow (or lateral epicondylitis as it is technically known). And it doesn't just affect your tennis - it affects your routine daily life from knocking in a nail to ironing your clothes. So what is tennis elbow. Well if you hold you playing arm out with your palm facing downwards and then put your on playing hand on top of your elbow, then clench and un-clench your fist you should be able to feel the muscles on your elbow tensing and un-tensing. This is the area where tennis elbow occurs. So if you are playing and you feel a pain or an ache in that area of your elbow STOP. Seek advice. It can be caused by poor technique especially on the backhand, or maybe a racket grip that is too small, or simply holding the racket too tightly. But whatever, don't wait till its too late because once you get it, it is a devil to get rid of.