The application of differential ratings of perceived exertion to Australian Football League matches

Objectives: To investigate the application of differential ratings of perceived exertion for the examination of internal load during Australian Football League (AFL) matches. Design: Single cohort, observational study. Methods: Using the centiMax rating of perceived exertion (RPE) scale, 26 professional AFL players provided ratings for match exertion (RPE-M), along with differential ratings for breathlessness (RPE-B), leg exertion (RPE-L), and technical demand (RPE-T) following 129 matches (5.0 ± 1.6 matches per player). Global positioning satellite (GPS) and accelerometer measures were also collected. Data were analysed using magnitude-based inferences. Results: RPE scores were 93.0 ± 8.2 AU (RPE-M), 89.0 ± 11.0 AU (RPE-B), 91.5 ± 9.8 AU (RPE-L), and 87.0 ± 10.0 AU (RPE-T). There was a most likely small difference between RPE-L and RPE-T (5.5%; ±90% confidence limits 1.9%), a likely small difference between RPE-L and RPE-B (3.5%; ±1.5%) and a possibly small difference between RPE-B and RPE-T (1.9%; ±1.9%). Within-player correlations between RPE and GPS measures were small for RPE-M (r= 0.14-0.28), unclear to small for RPE-B (r= 0.06-0.24) and unclear to moderate for RPE-L (r= 0.06-0.37). Differential RPE's combined to explain 76% of the variance in RPE-M. For all RPE scores, within-player variability was moderate to high (typical error: 7.9-12.4%), and the thresholds for a likely between-match change were 8.8-13.7%. Conclusions: As differential RPE's represent distinct sensory inputs, the collection of these scores facilitate the interpretation of internal match loads and therefore represent a valuable addition to match data collection procedures. Moderate to high within-player variability should be considered when interpreting between-match changes in all RPE scores.