Influence of endurance and sprinting exercise on plasma adiponectin, leptin and irisin concentrations in racing Greyhounds and sled dogs

Objective: The objective of this study was to assess the effects of both short-term anaerobic exercise and long-term aerobic exercise on leptin, adiponectin and irisin concentrations in both sprint and endurance canine athletes. Design: Prospective field trial repeated measures. The 25 racing Greyhounds were run over 400m, with blood samples collected prior to exercise and at 10min and 120min after exercise. The 16 sled dogs were run an average of 3.5-5h/day on 5 out of 8 days of stage stop racing competition, with assessment on days 0, 2 and 8. Results: Baseline leptin concentrations were found to be lower than previously recorded values of domestic dogs, possibly because of a lower body fat content in athletes, with concentrations in sled dogs being slightly higher than those in Greyhounds. Baseline adiponectin concentrations in both groups of dogs, on average, were lower than most previously recorded values in domestic dogs; although unexpected, these findings may be attributed to differences in body fat content of the study population. Conclusion: Endurance exercise in sled dogs resulted in a persistent decrease in leptin that appears to be independent of race-associated weight loss, with no appreciable changes in adiponectin or irisin concentrations. The anaerobic exercise of Greyhounds produced no detectable changes in leptin and adiponectin concentrations; however, a significant rise in irisin 10min post-exercise may be a compensatory mechanism for restoration of ATP homeostasis in skeletal muscle.