Kinetics of Rugby Union scrumming in under 19 schoolboy rugby forwards

Abstract

Two hundred and eight male rugby players from 13 high schools, whose ages ranged from 16 to 19 years, were used to examine the kinetics of Rugby Union scrumming. Force application, by each playing position, was recorded with the use of a force platform in the vertical (Fz), horizontal (Fx) and in the transverse horizontal (Fy) directions. The direction of force application in the vertical (Az) and horizontal (Ay) planes as well as the resultant force application (Fr) were calculated from the three orthogonal force components. The mean angle of force application during scrumming, in the horizontal plane (Ay), was 1.3o directed towards the tight head prop. During the initial shove and sustained scrumming phases, the front rows' direction of force application in the vertical plane (Az) was significantly greater (p < .01) than that of the second and back row forwards. No statistically significant difference (p > .01) was found between the various angles of force application (Az) produced by the second and back row forwards. The various resultant force applications (Fr) produced by the front, second and back row forwards during the initial shove and sustained scrumming phases however proved to be significantly different (p < .01). The greatest force application, in all directions, was achieved by the front row, followed by the second row and finally the back row. During the initial shove the average resultant force application (Fr) for the entire scrum was 8.6 kN and 1062 N per player. During sustained scrumming the average ground reaction force application for the entire scrum was 11.2 kN and 1400 N per player. Furthermore the results show that a significant correlation (p < .01) exists between the mass of the scrum and the resultant force application (Fr).



Keywords: Kinetics of rugby union scrumming, Force application, Direction of force application


South African Journal for Research in Sport, Physical Education and Recreation Vol.26(2) 2004: 33-50