The results of
at least two recent studies, however, suggest that reductions in
full - contact practices can be accompished safely without putting players
at additional risk, while researchers continue looking for the head trauma «holy grail»: a threshold - whether it is number of hits per week, over the course of the season, of a certain
force, or to a certain part of the helmet (e.g. facemask, top of the head) above which players are
at an unacceptably high risk of permanent
brain injury.