To test the interchangeability of 2 match-analysis approaches for external-load detection considering arbitrary selected speeds and metabolic power (MP) thresholds in male top-level soccer.
Data analyses were performed considering match physical performance of 60 matches (1200 player cases) of randomly selected Spanish, German, and English first-division championship matches (2013–14 season). Match analysis was performed with a validated semiautomated multicamera system operating at 25 Hz.
During a match, players covered 10,673 ± 348 m, of which 1778 ± 208 m and 2759 ± 241 m were performed at high intensity, as measured using speed (≥16 km/h, HI) and metabolic power (≥20 W/kg, MPHI) notations. High-intensity notations were nearly perfectly associated (r = .93, P < .0001). A huge method bias (980.63 ± 87.82 m, d = 11.67) was found when considering MPHI and HI. Very large correlations were found between match total distance covered and MPHI (r = .84, P < .0001) and HI (r = .74, P < .0001). Player high-intensity decelerations (≥–2 m/s2) were very largely associated with MPHI (r = .73, P < .0001).
The speed and MP methods are highly interchangeable at relative level (magnitude rank) but not absolute level (measure magnitude). The 2 physical match-analysis methods can be independently used to track match external load in elite-level players. However, match-analyst decisions must be based on use of a single method to avoid bias in external-load determination.
Castagna is with the Fitness Training and Biomechanics Laboratory, Italian Football Federation, Coverciano (Florence), Italy. D’Ottavio is with the University of Rome Tor Vergata, Rome, Italy. Varley is with the College of Sport and Exercise Science, Victoria University, Melbourne, Australia. Póvoas is with the Research Center in Sports Sciences, Health Sciences and Human Development, CIDESD, University Institute of Maia, Maia, Portugal.