According to the Daily Beast, the medical journal The Lancet revealed that “headbanging” - described as violently shaking the head in time with the music, most commonly in the rock, punk and heavy metal music genres — can cause damage as the brain bumps up against the skull”.
Apparently some 50 year old guy went totally gonzo at a Motorhead concert and suffered a bad head for a couple of weeks. Most doctors say the chances of longterm brain damage is very remote. And you were concerned about little Johnny heading the ball in soccer or playing other contact sports like hockey & football.
Here is a hilarious “instructional” video to headbanging. I didn’t know there were so many types. See where you fit: