The research by SU’s Department of Sport Science was conducted in partnership with the Department of Health at the University of Bath in the UK and published recently in the open-access journal Frontiers in Psychology.
A ruck is a phase during the game where one or more players from opposing teams, who are on their feet in physical contact, close around the ball on the ground.
The team enlisted the help of an international referee and rugby injury specialist analysing video recordings of 120 round robin matches, supplied by the Western Province Rugby Union video analysis department.
Dr Wilbur Kraak from the Sport Science department said it was the first time the non-sanctioning of dangerous illegal clean-outs at the ruck by on-field referees during a game had been investigated.
“Our study revealed that 2111 (9%) of these clean-outs were deemed illegal according to the 2018 World Rugby laws of the game at an average of 18 per match. Referees did not penalise 1953 (93%) of the illegal ruck clean-outs at an average of 16 per game,” Kraak said.
He said their findings should concern rugby referee stakeholders from an error rate perspective.
Kraak said that of the total illegal ruck clean-outs not sanctioned by referees, 1087 (57%) were considered dangerous at an average of 10 per match. The researchers found there were 22281 ruck clean-outs during the 2018 Super Rugby competition at an average of 186 clean-outs per game.
Using the video editing tool Nacsport Basic plus, the researchers coded and analysed video recordings to determine the rate at which illegal and dangerous ruck clean-outs were penalised by referees.
The experts found that the majority of the dangerous illegal clean-outs not penalised were “shoulder charge,” “neck roll” and “contact above the shoulder”.
In South Africa, rugby has the highest incidence of concussion amongst collision team sports. Up to 50% of high school rugby players would have suffered a concussion in their high school playing careers.
The researchers encouraged coaches to invite referees to officiate contact training sessions and drills according to rugby’s current laws to provide clarity to both players and coaches, with input from the referees.
Kraak said the findings of the study could lead to the development and implementation of further injury prevention strategies to make the game safer for all involved.