AUTHOR=Iwasaki Yusuke , Someya Yuki , Nagao Masashi , Nozu Shojiro , Shiota Yuki , Takazawa Yuji TITLE=Relationship between the contact load and time-loss injuries in rugby union JOURNAL=Frontiers in Sports and Active Living VOLUME=6 YEAR=2024 URL=https://www.frontiersin.org/journals/sports-and-active-living/articles/10.3389/fspor.2024.1395138 DOI=10.3389/fspor.2024.1395138 ISSN=2624-9367 ABSTRACT=Objective

Quantifying and managing the matches and training loads of players is important for injury prevention. As rugby union is a full-contact sport and frequent contact injuries occur, it might also be important to quantify and manage players’ contact loads. This study aimed to clarify the relationship between contact load and injury incidence in elite rugby union players.

Methods

Forty-eight elite rugby union players (27.0 ± 3.5 years) in Japan were monitored during one season (8 months). The contact load, an index of training load, was evaluated as collision count and collision load measured using a global positioning system device, and then calculated using the acute:chronic workload ratio (ACWR) based on the exponentially weighted moving average (EWMA). The association between the EWMA-ACWR of contact load and injury incidence was analyzed using generalized estimating equations.

Results

Of the 58 injuries during one season, 70.7% were contact injuries. Collision counts and collision load calculated by EWMA-ACWR were associated with the risk of injury (p < 0.01 both), with the odds ratios were 4.20 [95% confidence interval (CI): 1.74–10.11] and 4.44 (95% CI: 1.95–10.13), respectively.

Conclusion

Contact load calculated using EWMA-ACWR was associated with injury in elite rugby union players.