In a study from 2011, a survey of students at National Taiwan University will show most participants browsed a few paragraphs online before printing it out. When someone can choose if they want to read digitally or physically most people pick printed material.
The very nature of print materials is to target those who prefer visual and tactile physical encounters.
A person willing and wanting to take martial arts class has an affinity to visual and tactile physical encounters. That's exactly what a martial arts class is.
You watch things and then do things with other people and objects. It would make perfect sense why print is still a cornerstone of martial arts marketing.
And it's going to get better. People are becoming more attracted to value and good will than straight selling. Yes, it takes longer but it makes for a lasting tribe.
One that will stick around.