posted on 2017-07-27, 11:09authored byRomain Dubois, Thierry Paillard, MARK LYONSMARK LYONS, David McGragh, Olivier Maurelli, Jacques Prioux
The aims of this study were (1) to analyze elite rugby union game demands using 3 different approaches: traditional, meta-bolic and heart rate-based methods (2) to explore the relation-ship between these methods and (3) to explore positional differ-ences between the backs and forwards players. Time motion analysis and game demands of fourteen professional players (24.1 ± 3.4 y), over 5 European challenge cup games, were analyzed. Thresholds of 14.4 km·h-1, 20 W.kg-1 and 85% of maximal heart rate (HRmax) were set for high-intensity efforts across the three methods. The mean % of HRmax was 80.6 ± 4.3 % while 42.2 ± 16.5% of game time was spent above 85% of HRmax with no significant differences between the forwards and the backs. Our findings also show that the backs cover greater distances at high-speed than forwards (% difference: +35.2 ± 6.6%; p<0.01) while the forwards cover more distance than the backs (+26.8 ± 5.7%; p<0.05) in moderate-speed zone (10-14.4 km·h-1). However, no significant difference in high-metabolic power distance was found between the backs and forwards. Indeed, the high-metabolic power distances were greater than high-speed running distances of 24.8 ± 17.1% for the backs, and 53.4 ± 16.0% for the forwards with a significant difference (+29.6 ± 6.0% for the forwards; p<0.001) between the two groups. Nevertheless, nearly perfect correlations were found between the total distance assessed using the traditional ap-proach and the metabolic power approach (r = 0.98). Further-more, there is a strong association (r = 0.93) between the high-speed running distance (assessed using the traditional approach) and the high-metabolic power distance. The HR monitoring methods demonstrate clearly the high physiological demands of professional rugby games. The traditional and the metabolic-power approaches shows a close correlation concerning their relative values, nevertheless the difference in absolute values especially for the high-intensity thresholds demonstrates that the metabolic power approach may represent an interesting alterna-tive to the traditional approaches used in evaluating the high-intensity running efforts required in rugby union games.
Key words: Rugby union, GPS, heart rate monitoring,
History
Publication
Journal of Sports Science and Medicine;16, pp. 84-92