Diet plays an important role in the endurance potential of canine athletes. The Alaskan sled dog might be considered the ultimate canine athlete, sometimes pulling a sled more than 1,000 miles in subzero temperatures. Providing a well-balanced diet is essential to meet the special needs of dogs in such nutritional-stress situations. Not only should the diet fed to these dogs be high in protein, but it also should be high in fat, which serves as the major energy source for exercising muscles.
A high-fat diet can help muscles burn fat more efficiently. During sustained exercise, fatty-acid oxidation is the primary source of energy for the muscles. Increasing the efficiency of fat metabolism spares the body’s use of carbohydrates, and because most dogs have in excess of 10 to 50 times more energy stored in fat than in muscle glycogen (carbohydrate), this might boost the animal's exercise performance.
IAMS™ studies1 have shown that in trained sled dogs as in ordinary dogs, exercise performance was enhanced by switching from a low-fat to a high-fat diet (from 25 to 65% of calories from fat), as indicated by increased:
When dogs were switched back to a low-fat diet, all of these criteria decreased to their previous values.
These results indicated that by increasing the availability of fat stores and capacity to metabolize fat for energy, a high-fat diet promotes exercise endurance in canine athletes.
1 Reynolds AJ, et al. “The effect of diet on sled dog performance, oxidative capacity, skeletal muscle microstructure, and muscle glycogen metabolism.” Recent Advances in Canine and Feline Nutritional Research: Proceedings of the 1996 IAMS International Nutrition Symposium. Carey DP, Norton SA, Bolser SM, eds. Wilmington, OH. 1996. 181–198.
Does your mature dog sniff at his bowl and walk away instead of digging in? You may think he’s just being picky, but it’s important to keep an eye on how much he’s eating — especially if he’s a senior. While age-related diminishment of the senses of smell and taste may account for some of his disinterest in food, appetite loss can also indicate a serious medical problem.
“It’s important to give your dog enough calories because weight loss can be debilitating to senior pets,” says Wendy Brooks, D.V.M., who warns that a loss in appetite should be mentioned to your vet. A good rule of thumb: If your pet hasn’t eaten in a day, make a visit to the vet. Here are six ways to entice your canine friend with a nourishing meal.

Many animals find canned food more palatable because they like the taste and texture, Brooks says. You can top their favorite dry food with room-temperature wet food.
Dogs like a warm or room-temperature (not hot or cold) meal. Avoid serving him day-old wet food from the refrigerator, and keep his food away from heat. Another reason he might not be eating: It's too hot outside.
Dogs prefer consistency when it comes to their food. Don't change every day, but try a new flavor, such as lamb or chicken, and see if he responds (it may trigger his sense of smell). To avoid an upset stomach, introduce a new food by mixing it with his old food in equal increments each day.
Common mature-dog health issues, such as arthritis or joint pain, can make it difficult for him to access his bowls. Keep food and water where he spends most of his time. Put a water bowl on all floors of the house, too.
Older pets are at a higher risk of dehydration. Provide a clean bowl with fresh water at all times. It will help prevent disease, such as a kidney condition, and aid in digestion.
Dogs are people pleasers. If you see him eating, give him a little verbal reward. He'll know it makes you happy and will repeat the behavior.