 taking a good listen, make sure we don't hear any heart murmurs, any abnormal rhythm changes in the heart. Really make sure his ticker's good. Then the next thing is there are some hormonal problems that can cause weakness and an inability to tolerate what we'd call normal everyday exercise for dogs. And I'd say 30 minutes is pretty normal. So there are diseases like Addison's disease, which is a problem where a dog can have a low cortisone level.