Design sprints with people not from the field

I'm planning to do a design sprint on an app centered around Non-violent Communication with a group of volunteers not familiar with the concept.

I know there's an "Understanding" stage at the beginning of the sprint, but I'm wondering if that's going to be enough and how much time should I devote to it.

I've been thinking of preceding the sprint with a 4-hour workshop on the basics of NVC and then doing the sprint.

Do you have any experience with doing design sprints with people unknowledgeable about the field? How do you get them up to speed effectively?