Do not hurt the brain, especially not repeatedly.

In Brain Injury, Brain Science by Brainy Days Ahead

Cognitive impairment is common after a traumatic brain injury and it often affects quality of life. Researchers at the Center for BrainHealth at The University of Texas at Dallas have identified brain connectivity patterns in individuals having repeated traumatic brain injuries. “If key brain networks cannot interact in a normal way, the brain becomes inefficient.” Interpret that for yourself.