Unfortunately, you cannot train to take a harder hit.
i have a theory about this, actually. I wonder how many people have considered this :
way back when, before the gov't put rules in place regarding certain things, people lived a little differently.
we didnt have to wear helmets while riding our bicycles and skateboards, there wasnt a seat belt law until the mid 70's
there were no baby seats for cars either, kids were allowed to eat peanut butter in school ( and throw snowballs )
and so on.
now those kids grew up fine, and maybe went on to play professional sports. The Kids from that era would now be at retirement age from the game, or getting close to it.
the ones we see playing today, are from the age of mandatory helmets on bikes , and pro-active safety, no contact timbit hockey etc.
they are not used to getting their bell rung as a kid.
the reason there are so many concussions nowadays, is because they grew up wrapped in bubblewrap.
and for those that say the players are bigger,faster, equipment is harder etc..
take any player from the NHL or NFL in the 60's, 70's, or 80's and put em against todays wimpy players. and we'll see who was tougher.
players nowadays take a week off from a blister, or a cut, and even a hangnail !
im not saying every single player from now is a wimp, but the majority are. and i bet all the oldtimers that watch just shake their heads in shame