At this point, Apple is wasting a strong health branding component with its Apple TV product. Between the watch, iOS Motion, and Health Kit, Apple TV should be much more proactive than apps limited to logging meals (still easier to do on an iOS device) and offering coaching advice.
Imagine if there was an Apple TV app that communicated with the Watch. It could offer customized workout videos based on how active you are in everyday life and take into account how your body reacts to different exercises to get the best results possible. It would be a bit expensive to get started, but I think a lot of people would get really excited about this type of integration.
(Via Pixel Envy.)