This is a very short podcast about setting up Apple Fitness + on an Apple TV. The process is slightly different than that of an iPhone and iPad. The software update menu item is under Settings -> System -> Software Update.

If you don't already have the Fitness app installed on your Apple TV, then you will have to go into the App Store and search for the app and install it. Then, if you haven't already activated the trial on your iPhone or iPad, you can do so within the Apple TV app.

Using the TV app is a great experience for working out in your living room.