There are key differences in the nutritional requirements of human athletes and canine athletes. Most notably, dogs obtain 70% to 90% of their energy for work from fat metabolism, unlike humans who obtain the majority from carbohydrates. Studies have also shown that the dogs’ ability to use fatty acids through aerobic pathways is more important than the use of muscle glycogen through anaerobic pathways during hard work. What does this mean? Dogs that eat a high carbohydrate diet do not perform as well and are more susceptible to injury than those fed a higher fat, lower carb diet.
While dogs do use muscle glycogen during high energy, high intensity work such as sprinting, studies show that dogs who have been better conditioned more efficiently use the muscle glycogen. Thus, it is more important that a dog be adequately conditioned and exercised in a long-term program, and fed a diet higher in fat, than any type of human-esque carb loading.
With that said, there is a time and place for carbohydrates. Specifically, studies indicate that for both sprinting and endurance dogs, a carbohydrate supplement is good to give after bouts of strenuous exercise to enhance repletion of glycogen stores. For example, for a schutzhund dog competing in three phases in one day, giving a carbohydrate snack immediately after the 1st and 2nd phase will help the dog replenish muscle glycogen levels quickly and have optimal energy available for the next phase.