To investigate the patterns and performance of substitutions in 18 international 15-a-side men’s rugby union matches.
A semiautomatic computerized time–motion system compiled 750 performance observations for 375 players (422 forwards, 328 backs). Running and technical-performance measures included total distance run, high-intensity running (>18.0 km/h), number of individual ball possessions and passes, percentage of passes completed, and number of attempted and percentage of successful tackles.
A total of 184 substitutions (85.2%) were attributed to tactical and 32 (14.8%) to injury purposes respectively. The mean period for non-injury-purpose substitutions in backs (17.7%) occurred between 70 and 75 min, while forward substitutions peaked equally between 50–55 and 60–65 min (16.4%). Substitutes generally demonstrated improved running performance compared with both starter players who completed games and players whom they replaced (small differences, ES –0.2 to 0.5) in both forwards and backs over their entire time played. There was also a trend for better running performance in forward and back substitutes over their first 10 min of play compared with the final 10 min for replaced players (small to moderate differences, ES 0.3–0.6). Finally, running performance in both forward and back substitutes was generally lower (ES –0.1 to 0.3, unclear or small differences) over their entire 2nd-half time played compared with their first 10 min of play. The impact of substitutes on technical performance was generally considered unclear.
This information provides practitioners with practical data relating to the physical and technical contributions of substitutions that subsequently could enable optimization of their impact on match play.
Lacome, Piscione, and Hager are with the Research Dept, French Rugby Union, Marcoussis, France. Carling is with the Inst of Coaching and Performance, University of Central Lancashire, Lancashire, UK.