Answer: It extends the time of the collision
Since then the National Football League has made numerous rule changes to reduce the number of concussions suffered by players while making the game safer. In 2010 the NFL reworded the League’s rules to prohibit a player from “launching himself off the ground and using his helmet to strike a player in a defenseless posture in the head or neck.”
Timeline: The NFL’s Concussion Crisis | League of Denial …
In previous years with less padding tackling more closely resembled tackles in Rugby football with less severe impacts and fewer injuries .’ The comparison with Rugby Union is better because Rugby League is a collision sport without the padding . American Football many years ago tackles were much lower.
Concussions in American football – Wikipedia
Concussions in American footbal…