She's healthy so why?

She's definitely healthy! There are all kinds of reasons why your dog is groaning. Dogs groan because they're in pain or afraid (soft groan), excited (gasping), wanting something (continuous groaning), communicating with others (howling), or just sighing of boredom or disappointment. If you're worried that she's groaning because she's in pain or there could be something wrong, take her to her vet -- someone I'm sure would be able to figure out what's so upsetting to her. Best,`k.