He'll play indefinitely...at least, he's never asked to come in before my husband decided to throw in the towel himself. No more than 20 minutes to half an hour in this winter's cold. They go out twice a day like clockwork. Since they have no sweat glands on their skin, I don't think wind chill factors apply to dogs. Coby's never once acted cold---shivering or whining or heading for the door. Rather, he gets too warm inside. He always looks for the coolest place to sleep---often the stone tile of the shower floor at night. He does like to be close and will jump up on our bed for a few minutes at night, but quickly gets too hot and jumps back off again.
