Movement and impact characteristics of South African professional rugby union players

Abstract

Background. Global positioning system (GPS) technology can provide accurate, non-invasive, real-time movement analysis of playersparticipating in team sports. The application of this technology to rugby union will improve training practices by allowing improvedunderstanding of movement characteristics and more individualised programmes.Objectives. To characterise the movement and impact patterns of South African professional rugby union players during match play andcompare these to previously reported data.Methods. Nineteen professional rugby players were tracked using GPS systems during 24 matches during the 2013 rugby season. Playerswere grouped as (i) backs or forwards and (ii) tight forwards, loose forwards, scrumhalves, inside backs or outside backs. Movements werecategorised in speed zones corresponding to walking (0 - 2 m.s-1), jogging (2 - 4 m.s-1), striding (4 - 6 m.s-1) and sprinting (>6 m.s-1). Walkingand jogging were classified as low-intensity and striding and sprinting as high-intensity movement zones. An inbuilt triaxial accelerometer(sampling frequency 100 Hz) measured the total impacts >5G and high-intensity impacts >8G. All data were normalised to time on fieldand reported as mean (standard deviation).Results. There was no difference between forwards and backs in relative distance covered. Backs reached higher maximum speeds thanforwards (backs 8.8 (1.1) v. forwards 7.6 (1.3) m.s-1, effect size (ES) 1.0, and outside backs were the fastest positional group (9.4 (0.9)m.s-1, ES 0.4 - 2.2). Players in all positions spent the majority of time walking (79 - 84%). Backs covered more distance than forwards inhigh-intensity speed zones (forwards 11 (5) v. backs 14 (4) m.min-1, ES 0.7). Tight forwards covered the most distance in low-intensityzones (63 (6) m.min-1, ES 0.3 - 1.7) while scrumhalves ran the most distance in high-intensity zones (20 (5) m.min-1, ES 1.2 - 3.6). Highintensity: low-intensity running ratios ranged from 1:13 (tight forwards) to 1:3 (scrumhalves). Loose forwards and inside backs exhibitedsimilar movement patterns. There was no difference in impact variables between forwards and backs. Inside backs sustained the least totalimpacts (6.5 (1.2) >5G.min-1, ES 0.9 - 2.0) and high-intensity impacts (0.7 (0.2) >8G.min-1, ES 0.5 - 1.4).Conclusions. There were notable differences in the movement of professional rugby union players in different positions, and effectivetraining programmes should reflect these variations.