Every serious gun dog owner or trainer—whether concentrating on hunting, field trials, hunt tests or other gun-dog related activity—seeks to get the very best performance possible in the field. And, in order to get that peak performance, a dog has to be at his very best physically.

While most of us might call that getting a dog in “great shape” or “peak physical condition,” there’s another, more scientific phrase that you might not have heard of that relates to performance of both humans and canines: VO2 Max. And according to Dr. Kurt Venator, even if you don’t remember the phrase, understanding the concept can help all gun dog owners get the most from their canine companions.

But first a little about Dr. Venator. He has been with Nestle Purina for 17 years and currently serves as the company’s Chief Veterinary Officer. Venator earned his Doctor of Veterinary Medicine degree from Cornell University, and he earned a PhD in Zoology – Behavior & Physiology from the University of Texas at Austin. In his current position, Venator speaks across North America on the topics of small animal nutrition and veterinary medicine. He works closely with U.S. veterinary schools in order to create partnerships that foster nutrition education and professional development for the veterinarians of tomorrow. He also works actively with veterinary clinics across the country to enhance the role of nutrition in clinical practice and help pets live long, healthy lives. Lastly, he directs the Purina Advisory Council, a 20-member group of world-renowned veterinarians from various medical specialties who help us to advance pet nutrition, health, and wellness across the globe.

So when Venator talks about getting peak performance out of a working dog, wise dog owners listen. And concerning VO2 Max, he has a lot to say. “The key thing is to define what VO2 Max is,” Venator said in a recent interview with Gun Dog. “It’s not some odd scientific term. It’s simply the rate of maximum oxygen use. And obviously that’s important because oxygen is going to fuel endurance, performance, and energy. That’s both in dogs and in humans.

“As I like to describe it to people, the higher that VO2 Max, the more intense a dog can exercise and the longer it can maintain higher running speed. Why is this? It’s due to the supply of energy from fat that is going to the muscles. What you’re doing is you’re sparing the liver and the muscle energy stores stored as glycogen. What you want to do is give them a lot of protein and give them a lot of fat, appropriately, and you give them the energy to get to that high VO2 max. The more rate of maximum oxygen use goes up, then the higher the VO2 Max. And you have basically a higher capacity for both energy and endurance.” Before we get much deeper, it’s interesting to note that when comparing VO2 Max in dogs and human athletes, there is actually no contest, according to Venator.

“Canine athletes have a higher VO2 Max than average family dogs,” he said. “If your dog is an athletic dog—a high-performance dog—then he will have a higher VO2 Max than say a couch potato dog. In addition, all dogs, whether couch potatoes or canine athletes, actually have a higher VO2 Max than humans, even human athletes. “Dogs’ metabolisms and their capacity to be a performance athlete are essentially higher from a VO2 max standpoint than even your highest trained humans.” To understand VO2 Max, you first need to understand canine metabolism. And it’s completely different from the way human metabolism works.

“What we’re trying to do, whether a human athlete or a canine athlete, is efficiently consume more oxygen when exercising at your maximum capacity,” Venator said. “That’s going to fuel the aerobic energy and endurance. But the difference between dogs and people is that dogs are based on how well their body can use fat as energy. They’re not primarily relying on the limited energy stored in muscles and liver as glycogen. That’s what humans do. “So in dogs, it’s all about fat metabolism and what we call fat oxidation. And that provides most of the dog’s energy for the expenditure.”

Those athletes reading this will recognize how different that is from human performance. Human endurance athletes carb load ahead of time because they are dealing with carbohydrate oxidation. “For dogs, it’s the activation of fat metabolism,” Venator said. “And it’s also about high protein, not just fat, and conversion of amino acids, which are the building blocks of protein. “Those two things—that high fat and high protein—result in increased aerobic capacity and endurance. And that’s why when you’re working with a canine athlete and a sporting dog, beyond just conditioning and the proper training, nutrition is so important.”

Increasing VO2 Max  

Based on Venator’s information so far, it’s easy to see that we can increase the endurance and performance of our gun dogs by increasing their VO2 Max. Doing so takes not only conditioning, but proper nutrition so the dog has the right fuel to burn when working.

Which is most important—conditioning or diet? That’s a question I posed to Dr. Venator. “Without question, diet alone can actually change a dog’s athleticism,” he said. “Same with conditioning. But if you skip either one, you’re not going to be able to achieve what I’d call peak performance for that particular dog. If you’re doing the training, conditioning and pairing that up with a high-protein and high-fat formula, then you’re going to meet those metabolic needs. And that’s what we’re really talking about here.

“They have increased need for calories and increased protein metabolism that occur with the exercise. And that’s why it’s a combination of the protein and the fat. If you have that higher protein and fat food, it’s going to actually metabolically prime their muscles and their metabolism. So they’re going to be better at exercise and have better endurance.” Dr. Venator said while many gun dog owners understand the importance of fat in their dog’s diet, since dogs’ metabolisms are so different from humans, the protein aspect can be forgotten by some. “You can’t overlook the importance of protein,” he said. “You want high-quality, highly digestible fat and protein. As you know, after you exercise and during exercise there is a lot of protein turnover—you’re building up the muscle and breaking down the muscle. So that’s where you do want a high level of high-quality, digestible protein. So that way, after the exercise—and even during exercise—your protein turnover is going to increase. “And that’s exactly what you want. Because it’s the muscle, what we call metabolically active tissue, that’s resulting in the performance of that working dog. If you have highly digestible proteins, then you get the amino acids available and you’re going to get that muscle growth. I kind of see it as two things. You’ve got the combination of the muscle growth due to protein, and that fat, which is the energy source, that leads to performance.”

What’s Your Dog’s VO2 Max?  

So, how do you determine the VO2 Max of your hunting or field trial dog? Of course, we all want to know so we can compare it to the VO2 Max of our hunting buddy’s dog, just for bragging rights. In truth, however, the actual number, which sounds mostly like scientific mumble jumble, isn’t important at all. The key to increasing your dog’s performance is to push that maximum rate of oxygen use as high as you can.

“If you do proper conditioning and high quality food, you’re good to go,” Venator said. “You don’t need to worry about the numbers or even need to know what that VO2 max is. What you can feel comfortable about is knowing that because you are having proper training and conditioning and feeding of a high protein and fat diet, that will then get them to that high VO2 Max. And that’s the key for metabolism and endurance.”

Venator advocates owners of hard-working gun dogs use a 30/20 formula—30 percent protein, 20 percent fat—like Purina Pro Plan Sport 30/20, in order to give their hard-working dogs both the fat and protein they need. Other reputable companies make similar formulas; just make sure you pick one that has high-quality, highly digestible protein and fat.  

Such a recommendation brings up the topic of feeding during the off season. Most gun dogs have some down time each year, usually from late spring to the end of summer, when they aren’t participating in peak workload activities like they do during the hunting or trial season. When they are burning fewer calories, should an owner move to a different formula? Venator has heard that question many times.

“The good news is, gun dog owners know their dogs better than anybody else,” he said. “It’s a matter of balancing their conditioning program—how active are you being with them—with their diet. It could be a matter of just cutting back on overall caloric intake if they’re not working as much during that period. But I would say most folks, when it comes to the canine athletes and hard-working dogs, they should be fed that high-fat, high-protein performance protein year-round because it’s going to allow them to do that training and that conditioning. What you might want to do is just increase that amount when they’re at their peak and really performing.”

Pitfalls to Avoid  

While we shoot to achieve maximum VO2 Max in our working dogs, we’ve got to keep that relationship between diet and conditioning, or exercise, in mind. Too much food or too little exercise is likely to result in an overweight dog, not a high-performance canine athlete. Also a practicing veterinarian, Venator frequently sees overweight dogs at the clinic. And there are a number of reasons so many dogs suffer from that performance-dampening condition. “Dealing with general veterinary practice, the number one thing we see when people bring dogs in is obesity,” Venator said. “It’s a combination of three things. Part of it is feeding too much. The labeling on the bag is based on science and on feeding trials. So, when it says one cup, it means a measuring cup. It doesn’t mean a Slurpee cup. Sometimes vets will hand out measuring cups just so people will measure their food correctly.

Venator said another important part is activity. “If they’re not active, they’re going to tend to put on pounds,” he said. “There’s just no way around it.” Lastly is a factor that most gun dog owners will likely find surprising. And many will have to admit they’re at least partly guilty. “The third one, honestly what I see a ton in the exam room is treats,” he said. “People don’t realize how high rawhides or all these other treats are in calories. They can be wonderful, and I use treats, too, in training. The key is you’ve got to keep treats at no more than 10 percent of the daily caloric intake. So you have to look at the treats and figure out what your dog should be eating. But a lot of people don’t consider that.”

For many readers, VO2 Max might have been an unknown term before today. And honestly, you can forget the term right now, if you want. That’s because it’s not the term that is most important—it’s the overall concept and its relationship to canine performance. If you’re serious about getting peak performance out of your gun dog—and if you read this magazine I bet you are—move forward by helping increase your dog’s rate of maximum oxygen use. Between proper feeding, training and conditioning, you can have your dog running harder and longer than ever before. What’s not to like about that?