Effects of long-term running exercise on canine femoral head articular cartilage.

After long-term running program (40 km/day) anterior and posterior tissue samples from canine femoral head were labeled ex vivo in the presence of 35S-SO4. Sulfate incorporation rates did not differ between runner and control groups. The statistically significant changes in runners included a decreased uronic acid concentration (p < or = 0.02) and proportion of extractable proteoglycans (p < or = 0.05) as well as increased concentration of tissue uronic acid after 4 M GuCl extraction (p < or = 0.05) in the posterior area. These results support an idea of strengthened cartilage tissue after this kind of motion and load.