You may have heard of carpal tunnel syndrome (CTS) at one time or another. To put it in layman's terms, this is a condition in which one of the nerves running through the wrist to the hand becomes compressed, leaving the hand in pain or with weakness.
Did you know that potters can be one of the groups that is in a higher risk bracket for CTS? This is because we use our hands, wrists, and forearms so very much. For example, wedging and throwing are two activities that set us up for this form of repetitive motion injury.
Remember that working with clay is a physical effort, as well as being a source of satisfaction and fun. Before working, take five minutes to warm up your muscles, including the ones in your hands, wrists, and arms, with stretching exercises. Take plenty of breaks during your clay time and stretch out again. Several periods of doing these stretches can help reduce fatigue as well as stress on your joints, ligaments, and nerve bundles.
To help you better understand (and hopefully avoid) CTS, I've gathered together some helpful links.