Energy demands of playing positions in rugby union

Aims of the study - The objective of this work is to investigate the energy requirements of the different playing stations of play in rugby. Materials and methods - We collected the heart rate, and the nature, the frequency and the duration of the actions (video) of 40 players during matches. Five groups of stations were made up: prop and lock, hooker and loose forwards, scrum half, fly half and centre, wing and full back. The recordings of heart rate were carried out over all the duration of the matches, and were gathered in four zones (> 95%, 85-95%, 75-84%, < 75% FCmax). The actions taken into account during the analysis of the videotapes were waiting, the functioning, the jogging, the run, the sprint, the maul and the scrum. Results - The cardiac data showed that the forwards significantly spent more time carrying out intense exercises (higher than 85% of maximu heart rate) that did not the backs (p < 0.0005). The video data show differences of frequency and nature in the actions carried out according to playing position. The analysis of the succession between the rest and working periods shows that times of recoveries are rather similar to the working time for the forwards, and much higher for the three-quarters. Conclusion - Energy requirements of differents playing positions of play differ from one to another. Different physical and energetic conditionning programs should be build for each playing position. (C) 2002 Editions scientifiques et medicales Elsevier SAS.