Canine athletes burn energy at a tremendously higher rate than sedentary dogs. Their potential to maximize performance often relates to receiving an appropriate balance of energy nutrients based on the energy demands of the sport in which they compete.
“Dogs that perform endurance sports generally need a food in which fat makes up more than 50 percent of the energy in the diet to help increase stamina and maximize energy production,” says Richard Hill, M.A., Vet. M.B., Ph.D., assistant professor of clinical nutrition at the University of Florida. “Dogs that sprint also appear to require increased fat in the diet, but the energy needed for sprinting is small and it is unclear whether sprinting dogs require more than about 32 percent of the energy in the diet from fat.”
Though their sports and training programs vary, canine athletes typically are hardworking dogs that average more than 20 minutes a day in strenuous exercise four or five times a week, says Purina Nutrition Scientist Arleigh Reynolds, D.V.M., Ph.D. “Hardworking dogs have a different metabolic makeup than other dogs. To begin with, they have more lean muscle, which leads to an increase in their basal metabolic rate. Endurance dogs rely heavily on fat for energy and can become very deficient in utilizing fat. Even lean dogs store 50 times as much energy in fat as carbohydrate.”
Owners of competition dogs generally strive to feed diets that not only satisfy nutritional and energy requirements but also provide nourishment for physical stress and optimal performance. Regardless whether a dog competes in endurance sports, such as bird dog, coonhound or beagle tracking events, or sprint sports, such as lure coursing or racing, owners must consider several variables in their effort to give their dog a competitive edge.
Environmental conditions can have a dramatic effect on body temperature and a dog’s energy expenditure. “In warm environments, the heat generated by work must be dissipated to maintain body temperature within acceptable limits,” Reynolds says. “This results in panting, which takes significant energy.”
Maintaining energy balance in dogs that exercise in warm environments can be challenging due to the cost of cooling and the fact that warm weather decreases food intake. Because a large portion of energy use goes toward maintaining a constant body temperature, changes in ambient temperature affect the amount of energy needed for warmth or cooling. Generally, an increase in air temperature of 10 degrees Fahrenheit is associated with a 5 to 7.5 percent decrease in food intake.
However, the greatest energy expenditure measured in dogs was observed in Alaskan huskies performing in a long-distance race in temperatures averaging minus 35 degrees Celsius. These dogs consumed about 10,600 kilocalories a day, while their energy expenditure was estimated at about 11,200 kilocalories — seven times greater than their maintenance energy requirement.1
Energy Nutrient Distribution
Optimal dietary energy nutrient distribution is different for hardworking dogs, Reynolds says. Endurance dogs benefit from high-fat diets — those containing from 50 to 70 percent fat — because fat increases energy intake due to its density and palatability. In addition, high-fat diets fed during training help to alter a dog’s metabolism so that it is better able to utilize fat and spare limited carbohydrate sources.1
Protein is important to help reduce the risk of training anemia. One study showed that endurance dogs fed 19 percent of their calories as protein suffered significantly more injuries, had decreased oxygen uptake and fewer red blood cells than dogs fed diets containing 24, 32 or 40 percent protein. Dogs fed 40 percent protein had the highest circulating plasma than any group throughout training, showing that the increase in nutrient needs associated with exercise cannot be met with a low-protein diet.1
In a study of racing greyhounds, Hill found that a diet containing higher fat and protein and lower carbohydrate increased performance. “We compared a 32 percent fat, 25 percent protein and 43 percent carbohydrate diet to one with 25 percent fat, 21 percent protein and 54 percent carbohydrate,” he says. “These greyhounds ran an average of 0.2 seconds faster — the difference between winning and losing a race — when fed the diet containing higher fat and protein and lower carbohydrate.”
Feeding only fat and protein as energy sources is not enough. Without adequate carbohydrate, hardworking dogs could be at risk for depleting stores of muscle carbohydrate known as glycogen. “It is questionable whether dogs running in multiple heats on a single day or over several consecutive days adequately replenish their muscle-glycogen stores,” Reynolds says. “We determined that an immediate post exercise carbohydrate supplement helps to promote more rapid muscle glycogen repletion in the first four hours of recovery.”
Achieving Top Performance
Regardless of the sport in which a dog competes, an owner can help his or her dog handle physical stress by feeding a complete and balanced diet that provides an optimal mix of energy nutrients. Dogs generally are able to channel energy demands in a positive and healthy way if they are provided adequate nutrition and the right energy balance to help them achieve top performance. Highly active dogs benefit from a diet with a high percent of calories from fat. Less physically active dogs may respond better to carbohydrate as a primary energy source. ©
1. Reynolds AJ. Energy Metabolism and Substrate Utilization in Dogs. Purina Nutrition Forum Proc., St. Louis, 1998, p.126-128.