How hard do you have to be hit to sustain a concussion? — Dr. Mark

How hard do you have to be hit to sustain a concussion? This will come as a shock to no one: You must be hit very hard to sustain a concussion; not just any bump will do. 

How hard do you have to be hit to sustain a concussion? — Dr. Mark Heisig

How hard do you have to be hit to sustain a concussion? — Dr. Mark Heisig