I didn't mean it offensively, they literally wear skirts and the majority of schools only have it as a girls sport lol.
But comparing the contact in american NFL football to football (not soccer) anywhere else isn't even comparable. Without those helmets all of them would have PCS and would have dementia by their 50's. I assume Australian football is more like rugby where most of the contact is being dragged down as opposed to head on head, head on shoulder collisions.
Rugbys- highest force for a tackle was recorded at approx 1600lbs
Nfl- 4600lbs
nhl- i assume is much more due to faster velocity and more room to accelerate usually. The unstable surface also makes the impact bigger.
Hockey wins just based on this video
http://youtu.be/-5xkMNIt-5k