Regular exercise has become an international pastime, and physicians question if regular exercise will accelerate the development of osteoarthritis (OA). I review current literature about the effect of regular exercise on the risk of developing OA in normal and abnormal joints. With low impact activities, the risk of developing OA in normal joints is not increased. Individuals who participate in sports with abnormal or injured joints or at a highly competitive (elite) level appear to be at increased risk of developing OA. Longitudinal studies of young athletes after elite level performance or after joint injuries will allow us to substantiate these findings.