My almost 2 year old border collie has typical border collie energy when she plays and when there are people and dogs around, however, she always gets tired quicker than any of my previous bc's. She has a white face so around her eyes get progressively more pink the more tired she gets. She's smart and obedient and loves to have jobs to do. But the interesting thing is the more tired (within 15-20 mins of playing or hiking or running) she gets, and the less obedient she is. Simply because everything goes over her head and she becomes delirious. My two previous border collies had boundless energy until they reached a more mature age, so this is new to me. I wonder if she'll have more energy the more she matures? I know many dogs who sleep most of the day, but for her its very much a need. I have to make sure she is able to have long naps throughout the day so we can do fun things. Anyone have thoughts or experience anything similar?