The study, published in the Canadian Medical Association Journal, says prohibiting things like bodychecking would reduce the amount of brain and spine injuries suffered by young players.

"We found that interventions based on rule changes showed the greatest likelihood of making ice hockey safer for youth," said neurosurgeon Michael Cusimano, of the Injury Prevention Research Office at St. Michael's Hospital and the University of Toronto.

Cusimano said there's been an increase of brain and spinal cord injuries among young hockey players during the past 15 years. Brain injuries account for 15% of all injuries in players ages 9 to 16.

The study says aggressive acts are responsible for one-third of injuries. Findings show students who play varsity hockey to relieve aggression are four times more likely to experience a concussion than other players.

"These findings highlight the association between aggressive behaviour and injury in ice hockey. Rule changes essentially alter the culture of a sport and clearly define acceptable behaviour for all stakeholders (players, coaches, parents and officials) simultaneously," the study says.