However , the injury rate was unchanged in senior players over the same time period .
In the four years after its implementation , there had been a nationwide reduction of , on average , 2.5 catastrophic injuries per year in junior players over a four - year period .
The injury rate was unchanged in senior players over the same time period .
In the four years after its implementation , there had been a nationwide reduction of , on average , 2.5 catastrophic injuries per year in junior players over a four - year period .