Dogs quite often sleep in ways that look very uncomfortable from a human perspective. Sleeping upside down with their legs akimbo might look strange, but there are several very good reasons why dogs choose this position.
It helps them stay cool
Relative to many other animals, dogs aren’t great at regulating their body temperature.
Humans can regulate their temperature by sweating from almost every part of their body, but dogs don’t have that luxury. Instead, they cool off by using air to push heat from their body, such as by panting.
Sleeping on their back is another way that dogs can stay cool. The fur on their belly is thinner than other parts of their body, so a passing breeze can more easily blow away excess heat. It also exposes their paw pads, which is one of the few places from which dogs can sweat.
When a dog is sleeping on its back, all of the pressure that would usually be on their leg muscles and joints is relaxed. Sleeping with floppy legs in the air doesn’t look comfortable to us, but dogs find the position extremely satisfying.
Dogs with joint problems or arthritis can get a better quality of sleep when they’re able to find a comfortable upside-down position.
It shows they feel safe
Dingos, wolves, and other wild dogs are never seen sleeping on their backs. In the great outdoors, an animal sleeping in such a vulnerable position would be at significant risk from predators.
When your dog sleeps upside down with an exposed belly, what they’re really doing is telling you they feel safe and secure. They’re sleeping confident in the knowledge that they’re not about to be attacked.
Beds for dogs that sleep on their back
Dogs that prefer to sleep upside down may benefit from a flat-surfaced bed, preferably one with side cushioning (to prevent rolling off) and an orthopaedic mattress for back safety.