Apple TV goes to sleep while playing movies or shows

I've had this problem for a while. When I set my Apple TV to sleep in say, 1 hour, I assume that is 1 hour after no activity, but no it goes to sleep after 1 hour even if I am watching a movie or a show, is this how it is designed to work? The only work around is to set the sleep to the highest setting, but after I'm done with the device it stays on for the next 4 hours, which isn't a big deal but it does waste electricity.