We ask a lot of our dogs. We ask them to resist food on the counter, to stay inside when the front door is open and to be quiet when dogs are barking next door. With my new puppy, I’ve been thinking a lot about self-control, which is the foundation for everything from household manners to agility skills.
In humans, research has shown that there’s a relationship between the brain’s glucose supply and self-discipline. A recent study found that this is true for dogs too. 
The experiment, published in this month’s Psychological Science, looked at the length of time a dog worked at an impossible task.
In the study, some of the dogs were put in a sit-stay for 10 minutes to “deplete their fuel reserves” and the rest of the dogs were put in a crate for 10 minutes. The dogs were then given a treat dispensing toy, known as a Tug-a-Jug, altered to make it impossible to get the food out.
The dogs who exerted self-control in the sit-stay gave up after less than a minute, as opposed to the crated pups who gave up after over two minutes.
The scientists hypothesized that the self-control needed for the sit-stay depleted the dogs’ blood sugar supply, weakening their ability to exert “goal-directed effort.”
To test this theory, the scientists repeated the experiment with one difference. Half of the dogs performing the sit-stay got a sugar drink before going on to the Tug-a-Jug task. As a control, the other half got an artificially sweetened drink.
Amazingly, the sit-stay dogs that got the sugar drink performed just as long as the crated dogs. The pups who got the artificially sweetened drink showed no improvement.
Most of us will probably never give our dogs a performance-enhancing drink, but it’s interesting to know how taxing the behaviors are that we ask of our dogs. When I’m training, I usually alternate between practicing impulse control  and playing games like tugging . Now I see why it’s so important to keep training sessions short and fun!