The progression of GPS technology and analysis software has led to many different metrics being measured by the systems commonly used. It is important for coaches to decide which metrics to measure and record for the purpose of monitoring workload. In general, unless the coach is working at a high level of rugby with additional support for analysis of the GPS data, it is advisable to focus on only a few metrics that may provide the most value. The coach should use metrics that can inform their coaching practice and not just record and analyse metrics for the sake of doing so. GPS metrics can also be calculated or analysed differently by different manufacturers or researchers, so it is important that when looking at GPS data the coach understands what that metric is specifically referring to.
Figure 7: GPS monitoring assists in describing and monitoring each player's workload.
Some common GPS metrics that are recorded in rugby games and training are:
- Total distance covered. The distance covered by the player in the game or training session (Hennessy and Jeffreys 2018)
- Relative distance covered or metres per minute. This is expressed as total metres in each minute and as an average during a specified period (Hennessy and Jeffreys 2018)
- High speed running distance/time. Time spent, or distance covered running at speeds above 5.5–6m/s (Hennessy and Jeffreys 2018; Tee et al 2016; Flanagan et al 2017)
- Repeated high intensity exercise bout. A repeated high-intensity exercise bout was defined as three or more sprints, scrums/rucks/mauls, and/or tackle efforts with less than 21 seconds recovery between high-intensity efforts (Gabbett 2015)
- Acceleration frequency or total number. Accelerations are typically calculated as an increase in speed for at least half a second with a maximum acceleration in that period of at least 0.5m/s2. The total number of accelerations in a time period or how often they occur in a time period are often reported (Hennessy and Jeffreys 2018)
- High Metabolic Load Distance. The total distance covered via high speed running (>5.5m/s) and high accelerative actions (2m/s2) (Flanagan et al 2017).
Quantifying player workload requires analysis of all the activities a player undertakes during a training and competitive period. To gain a comprehensive understanding of the workload being placed on a player, both game and training activities such as skills sessions, small-sided games, technical and tactical unit training, interval training etc. could be analysed using GPS data.
Logistically this can be very challenging for a coach to organise and it may not be possible to involve GPS recording in every part of training. It may be advisable for a coach to use GPS during certain more unpredictable, higher intensity training sessions like small-sided games and to use other measures such as RPE for skills sessions. This combination approach to workload monitoring may be more practically feasible.