Osteoarthritis has been held to result from wear and tear. We addressed this hypothesis by analysis of anteroposterior radiographs of the knees of 51 subjects with mean age of 60 years who regularly practiced weight-bearing exercise. Radiographs were assessed for longitudinal changes in spur formation over a two-year period. The results showed a negative association between changes in weight-bearing exercise and changes in the rate of spur development in both males and females. The findings suggest that increasing repetitive impulse loading in the form of regular painless weight-bearing activity does not promote osteophytosis (or perhaps degenerative disease) in knee joints.