The effect of creatine monohydrate supplementation on blood lactate and performance in agility dogs

Creatine (Cr) is widely used as supplement in human athletes. Its effect is to increase the muscle storage of phosphocreatine (PCr) and enhance the restoration of adenosine triphosfate (ATP) during short and high-intensity exercise. Anaerobic energy release results in depletion of phosphocreatine and accumulation of lactic acid, which set an upper limit of anaerobic ATP production that can influence the performance. The exclusive use of conventionally dry diets seems to lead to a low availability and intake of Cr especially for sport dogs. Since we have very few information about the effect of Cr supplementation in dogs, the aim of this work is to evaluate blood lactate and performance after 15 days of Cr monohydrate supplementation in dogs performing an agility test. Six adult Border Collies were used for the trial. The dogs were regular competitors, well trained and at the same level in agility official competitions. The animals were fed a dry commercial diet (27% protein, 17% fat as fed) and remained with their owners without any changes in their life and habits. The dogs performed a simulated agility competition consisting in 18 obstacles and 156 m long. The course was performed twice with the same handler and 1 minute rest between the two runs was set (Test 1). Time was measured with wireless photocells at the end of each run. Blood lactate was evaluated with a portable device (Accusport, Boheringer) at rest, after the first run, at the end of second run, and after 1 hour rest. After a period of 15 days of Cr monohydrate supplementation (0.2 g/kg BW), all dogs performed the same test again (Test 2). Results of the Test 2 showed speed improvement during R2 compared to R1 (22.70±0.45 s vs 23.19±0.38 s). Differences between the first (R1) and second (R2) run, before and after the supplementation period were analyzed by Anova. Significant difference (p<0.05) between R1 and R2 runs was found before and after the supplementation periods (+0.07 s vs -0.49 s respectively). Furthermore, the difference between R1 and R2 in lactate production was lower in the Test 2 but not significantly different from Test 1 (0.87±0.33 mmol/L vs 1.82±0.28 mmol/L). The 0.2 g/kg BW Cr monohydrate supplementation for 15 days improved performance in dogs submitted to a high and fast agility exercise, but further and more exhaustive studies should be carry over to better understand the metabolic effects of Cr supplementation in dogs.