You need both.
You need strength for everyday activities such as getting yourself out of a car seat or off the couch. You need endurance to continue doing activities such as walking while carrying grocery bags or a child.
There are three different muscle fibers: fast twitch fibers are for strength, slow twitch fibers are for endurance, and intermediate fibers that do both. You train for strength with up to 6 reps as heavy as you can. Most of Cathe's videos take care of the endurance aspect.