Spin out from a FaceBook conversation.
There's two weird ideas about martial arts instructors that are both interconnected. The first is that being a teacher means that you must spend a lot of time training. The second is that you are exhibiting a great deal of dedication by spending so much time at the gym. Neither is necessarily true.
Teaching is teaching. Training is training. If you're doing it right, the two will rarely coincide. If you're teaching, you're focused on the students, which means you are providing instruction, supervising drills, and taking care of the hundreds of other major and minor tasks that go into running an effective martial arts class. Rarely does that leave you any time to train yourself. Depending on the class and the circumstances, you may get to work in for a drill or a round of sparring, but even then, you are (or should be) focused on developing your students, not yourself. It's not your time.
That means that, as an instructor, you need to carve out your own time to train. That can be challenging, bordering on impossible. It means that your training needs to take place not during class time, but during odd times that don't coincide with your classes. Many instructors I know train during the middle of the day, or do what training they do mostly through seminars or the occasional odd session with an advanced student. How much of this you can do will depend on your resources, but bottom line--teaching time isn't training time.
The level of dedication is arguable. For instructors who have other jobs, and teach for the love of the art or the love of coaching, I would agree that there is a great deal of dedication there. There is dedication in the life of a professioanl instructor as well, but it's really just the dedication of showing up for your job. No one says "Man, you're in the office five days a week! You're so dedicated!" You show up because it's your job. Granted, the life and schedule of a professional instructor, particularly a school owner, can be more hectic and harried than that of someone punching the clock in a cubicle, but it's still a job. Dedication only goes so far.