The relationship between changes in interstitial creatine kinase and game-related impacts in rugby union

Abstract

CK increased from pre-game to post-game in a position-specific manner. A large proportion of the Delta[CK] can be explained by physical impact and thus can be predicted using a prescribed number of game statistics. As the Delta[CK] is an indicator of muscle damage, the prediction of Delta[CK] provides a theoretical basis for recovery strategies and adjustment of subsequent training sessions after rugby union games.

The Use of Accelerometers to Quantify Collisions and Running Demands of Rugby Union Match-Play

“…Almost certainly greater differences between forwards and backs were seen for total collisions, similar to findings in elite senior rugby union players (Smart et al, 2008, Jones et al, 2014.…”

“…This finding suggests that scrums may contribute to the overall load sustained by forwards during match-play and therefore unlike in previous research (e.g. Smart et al (2008)), should be considered as part of the over-all collision count when assessing collision activity in this positional group.…”

“…Collisions and impacts during match-play were coded by an expert analyst using the same criteria as Smart et al (2008). The specific collisions coded were tackles made, hit-ups, being one of the first three to an attacking breakdown (first three attack), being one of the first three to a defending breakdown (first three defence), total collisions (sum of all collisions sustained during the match) and scrums using Sportscode (Sportec, NSW).…”

“…A secondary aim was to investigate if accelerometer metrics differed between forwards and backs. Recent research in senior players has demonstrated large differences in both collisions sustained during match-play (Smart et al, 2008) and in PLslow (McLaren et al, 2015) between forwards and backs. However, no current study has investigated this phenomenon in a single study.…”

“…Tackle detection algorithms are available within the micro-technology software, and have been successfully used for detecting and quantifying hit-ups and tackles in rugby league (Gabbett et al, 2010). However, rugby union also involves other types of collisions (e.g., rucks, mauls), which contribute to a large portion of the total collisions during match-play, particularly in the forwards (Smart et al, 2008). Providing accurate information regarding such collisions requires the time-consuming process of aligning raw accelerometer data with video (Gastin et al, 2014), or sophisticated modelling (Kelly et al, 2012), which may not be feasible for many practitioners.…”