Time-motion analysis via Global Positioning Systems that discriminate between successful and less-successful South African, U/18 provincial sevens Rugby teams

Abstract

Despite the popularity of Sevens Rugby, due to its Olympic status, very limited scientific research exists to date. Such knowledge may shed light on the physical demands that this sport places on the participants during match play. The purpose of this study was to determine if movement velocities discriminated significantly between the successful (top eight teams) and less successful (bottom eight teams) South African, u/18 provincial Sevens Rugby teams. The movement velocities, frequencies, distances and duration of hundred and sixty players who represented sixteen provinces at the 2011 South African Sevens Rugby Tournament were recorded using the Catapult Minimax (Catapult 10Mhz). The movements were categorized according to the velocities as determined by Castagna and D’Ottavio (2001). Finally work to rest ratio’s were determined. The effect size results of the differences between the successful and less successful teams indicated that walking efforts, walking time and high intensity running efforts displayed a moderate practical significant difference between teams compared to walking distance which obtained a small practical significance value. The results of the forward stepwise descriptive analysis revealed that the percentage time spent on walking, distance and high intensity running distance together with the number of high intensity running efforts significantly discriminated (p ≤ 0.05) between successful and less successful Sevens Rugby teams. The classification matrix showed that the discriminant analysis prediction functions were 77.5% accurate in classifying the different teams back into successful and less successful groups. The average work to rest ratio for all the matches, was found to be 1:18. Furthermore, the results showed that the percentage time spent walking, walking distance and high intensity running distance together with the number of high intensity running efforts, discriminated significantly between successful and less successful Sevens Rugby.

Keywords: Time motion analyses, Sevens Rugby, rugby, work rest ratios, GPS sport tracking.