Pre-binding prior to full engagement improves loading conditions for front-row players in contested Rugby Union scrums

• Published in: Scandinavian journal of medicine & science in sports Vol. 26; no. 12; pp. 1398 - 1407
• Main Authors: Preatoni, E., Cazzola, D., Stokes, K. A., England, M., Trewartha, G.
• Format: Journal Article
• Language: English
• Published: Denmark Blackwell Publishing Ltd 01-12-2016
• Subjects: Adult; Athletic Injuries; Biomechanical Phenomena; Biomechanics; Cross-Sectional Studies; Football - injuries; Humans; Impact biomechanics; injury prevention; Male; Pressure; Rugby; scrummaging technique; sports performance; Stress, Mechanical; wearable sensors; Weight-Bearing; Young Adult; wearable sensors; pressure; injury prevention; scrummaging technique; Impact biomechanics; sports performance
• ISSN: 0905-7188; 1600-0838
• DOI: 10.1111/sms.12592

We investigated the effect of a “PreBind” engagement protocol on the biomechanics of contested Rugby Union scrummaging at different playing levels. “PreBind” requires front‐row props to take a bind on opposing players prior to the engagement, and to maintain the bind throughout the scrum duration. Twenty‐seven teams from five different playing levels performed live scrums under realistic conditions. Video analysis, pressures sensors, and inertial measurement units measured biomechanical outcomes as teams scrummaged following different engagement protocols: the CTPE (referee calls “crouch‐touch‐pause‐engage”), the CTS (“crouch‐touch‐set”), and the PreBind (“crouch‐bind‐set”) variants. PreBind reduced the set‐up distance between the packs (−27%) and the speed at which they came into contact by more than 20%. The peak biomechanical stresses acting on front rows during the engagement phase were decreased in PreBind by 14–25% with respect to CTPE and CTS, without reducing the capability to generate force in the subsequent sustained push. No relevant main effects were recorded for playing level due to within‐group variability and there were no interaction effects between playing level and engagement protocol. Pre‐binding reduced many mechanical quantities that have been indicated as possible factors for chronic and acute injury, and may lead to safer engagement conditions without affecting subsequent performance.