Why do dogs pant and shiver at the same time?

Dogs do not shiver and pant at the same time. Panting is a normal behaviour of dogs to regulate their body temperature, they do not shiver while panting. Shivering is associated with feeling cold or discomfort. If you observe a dog shivering and panting simultaneously, it might be an indication of an underlying health condition and it would be recommended to have them checked by a veterinarian.