Former college varsity athletes were surveyed by questionnaire to determine if long-distance running can be implicated as a factor in the future development of osteoarthritis of the hips and knees. Subjects were divided into two groups. One group consisted of 504 former varsity cross-country runners. A control group consisted of 287 college swimmers. Follow-up periods ranged from two to 55 years, with a mean of 25 years. In former runners there was a 2% incidence of severe pain of the hips and knees. In former swimmers there was an incidence of 2.4%. Additionally, 2.1% of swimmers eventually had had a surgical procedure for relief of pain. Only .8% of runners eventually required surgery for osteoarthritis. There is no association between moderate long-distance running and the future development of osteoarthritis. Furthermore, the evidence suggests that neither heavy mileage nor the number of years running are contributory to the future development of osteoarthritis.