Lower rugby tackle height linked to drop in head collisions – study

Lowering the tackle height in men’s community rugby has cut the rate of head collisions among players, a study suggests.

The research assessed the impact of the lowered tackle height law, which was introduced for community rugby by World Rugby in the 2023/24 season as part of efforts to improve safety for players.

It recommended an opt-in international trial of lowering the tackle height from the shoulder to below the sternum or breastbone – also known as a belly tackle.

Researchers at the University of Edinburgh used video analysis to study 18,702 tackles from 60 men’s community matches in Scotland to compare the 2022/23 (pre-trial) and 2023/24 (trial) seasons.

Our findings show lowering the maximum legal height of the tackle in men’s community rugby proved effective in altering tackling behaviour

They found lowering the tackle height was linked with a 45% drop in head-on-head contact – one of the main causes of sports-related concussion.

It was also linked to a 29% reduction in head-to-shoulder contact for the tackler and ball-carrier.

The study’s lead author, Hamish Gornall – of the University of Edinburgh’s Moray House School of Education and Sport, said: “Our findings show lowering the maximum legal height of the tackle in men’s community rugby proved effective in altering tackling behaviour in line with the aim of the recommendations.

“Collecting prospective injury data, as well as continued monitoring of player behaviour across subsequent seasons would be beneficial to further investigate the implications of the change.”

The researchers analysed footage from Scottish Rugby which recorded players’ activity including tackle type, body position, contact point and head contact.

This data was then coded according to guidelines developed by World Rugby.

Researchers found that during the 2023/24 season, players were 22% more likely to tackle bent at the waist, the recommended technique to reduce player head proximity and contact.

Researchers also found the change in tackle height was linked to a 19% drop in the rate of head and upper torso contacts to the ball-carrier and an increase in frequency of tackles to the ball carrier’s lower torso and upper legs.

The study is part of an international project led by World Rugby to assess the effects of lowering the tackle height in Scotland, England, France, Ireland, Italy, Japan, New Zealand, Scotland, South Africa and Wales and Australia.

Dr Debbie Palmer, of the Institute for Sport, Physical Education and Health Sciences at the Moray House School of Education and Sport, and co-director for the UK Collaborating Centre on Injury and Illness Prevention in Sport IOC Research Centre, said: “As a collision sport, head injuries in rugby are a reality, and in an effort to protect players this is one of the biggest law changes the community game has seen in recent years.

“These initial results are very encouraging. The team are also evaluating the impact of the law change in Scottish women’s and youth community rugby.”

Researchers found no significant increase in tacklers’ heads coming into contact with the ball-carriers’ hips or knees, which is associated with an increased risk of head injury assessments and concussion diagnosis.

The trial was adopted by Scottish Rugby and made compulsory across all amateur playing levels.

Scottish Rugby chief medical officer Dr David Pugh said: “At Scottish Rugby we strive to reduce the incidence of concussion in as many ways as we can.

“We are also working with the university on an injury surveillance project, and we hope that this will see a significant drop in concussion rates due to the lower tackle height trial.

“Hamish’s research clearly demonstrates that player behaviours have changed, reducing head-to-head and head to shoulder contacts which should lead to reduced numbers of concussions in our players.”

The study is published in BMJ Open Sport and Exercise Medicine.