This one is very similar to crazy legs sleeping position. Scientists say the passed out position may be a sign of an overheating. This is because a dog’s paws contain sweat glands, and their belly has the least amount of fur on their body, ultimately making this position super effective for cooling off. Be aware, however; if your dog has their paws curled over their chest while ‘Passed Out”, they are telling you they don’t want to be bothered. So, take the risk if you want to wake them up.
The Belly Curl is similar to the Curly Sue, except the dog’s body isn’t as tightly wound up. If your dog is sleeping using belly curl, they may not be getting the best sleep quality. According to Dog’s Best Life, when dogs are sleeping in this way muscles are not allowed to be relaxed at all, so they can not enter in a deep sleep, REM stage of sleep. Dogs who belly curl tend to be gentle and shy— but some are the most adventurous of the pack!