Using GPS-generated physical metrics
Matthew Blair, Simon Body and Hayden Croft have been using GPS technology to analyse the physical performance of elite Rugby Sevens players.
The global emergence of this form of rugby union brings with it a need for improved understanding of the physical requirements. Strategies to enhance team performance need to be evidence-based.
Data were collected from six tier two rugby unions. During four 2013 World Series tournaments 40 players wore a heart rate strap and a GPS tracking device. Anthropometric data was measured during the first two tournaments. All the variables were visually represented using self-organising maps (SOMs). Points differences (positive for a win, negative for a loss) were also mapped this way but no single physical metric predicted winning. The SOMs for metabolic power, high-speed running distance, high-speed running time, total distance, accelerations, decelerations, and sprinting showed similar patterns, indicating a strong relationship between these physical metrics. The similarity in the patterns of the SOMs for body composition and dimension variables also demonstrated a strong relationship. Other physical metrics showed no strong relationship with any other metrics.
The average total distance travelled by players in this study, and their body composition and dimension data, together indicate that the tier two players studied did not achieve the work normally required to compete physically at a World Series 7s tournament. Increased effort is needed in pre-tournament physical preparation for tier two players.
No relationship emerged between high-speed running and high intensity heart-rate, possibly because other factors like anxiety contribute to higher heart rates. Likewise no relationship was observed between heart rate and rate of perceived exertion (RPE) during the games, which suggests caution is needed when using RPE. However the relationship between high-speed running and metabolic power is important and relevant for the preparation of 7s specific training schedules.