Your dog may be sleeping on their back with their legs up because they feel safe and comfortable around you. However, it is not always that deep and serious. Here is a bit more insight on why your dog may prefer this sleeping position.
Dogs love to be comfortable and will twist their furry little bodies into whatever shape or position that allows them to enjoy this comfort the most. Therefore if you find your dog sleeping on their back, it could simply be because they feel the most physically comfortable in that position.
Show Their Trust
A dog’s belly is considered to be a vulnerable part of its body. By sleeping on their backs, they are essentially trusting their lives in your hands.
If your dog rolls over onto their back while you are cuddling or while you pet them in their sleep, it is their way of letting you know that they trust you.
To Cool Down
Unlike humans, dogs do not sweat through all parts of their skin when they get hot. The sweating is typically limited to the paw pads.
While they are awake, they rely on panting to cool themselves down. However, while they are asleep, they change their sleeping positions as a way to cool down.
Sleeping on their backs with their legs in the air is one way to cool down as more of their body surface area is exposed to moving air for a cooling effect.
To Avoid Abdominal Discomfort
If your dog is sleeping on their back, it could also mean that they are experiencing some abdominal discomfort. It could be something like being excessively full.
This may not cause enough discomfort to disrupt their sleep but may require strategic positioning like sleeping on the back as opposed to sleeping on the abdomen.