“I have a theory on concussions. I think the reason there’s so much more of them — obviously the impact and the size of the equipment and the size of the player — but there’s another factor: everyone wears helmets, and under your skull when you have a helmet on, there’s a heat issue. Everyone sweats a lot more, the brain swells. The brain is closer to the skull. Think about it. Does it make sense? Common sense?” -Randy Carlyle
Helmet swelling can cause concussions. This is my dark room.