Author(s): HÖLTKE, T., BRINK, M., BUURKE, T., KEMPE, M., Institution: UNIVERSITY OF VIENNA, Country: AUSTRIA, Abstract-ID: 1341

INTRODUCTION:
Load quantification is widely used during elite football matches to guide training prescription and manage injury risk, and is commonly analyzed uniformly across running intensity zones. However, understanding zone-specific variability is important when interpreting whether a player's match load deviates from their individual 'normal load profile'. Previous studies reported variability estimates using small single-team samples [1,2] with statistical approaches that were largely descriptive [1] or suboptimal [2], limiting robust inference and preventing positional comparisons. Therefore, this study aimed to quantify full-season match-to-match variability across running intensity zones and playing positions in elite football.
METHODS:
Match running demand metrics were obtained from 2D tracking data of 150 outfield players (23.8 ± 4.5 matches) across all teams in a full-season professional league. Running demands were expressed as distance covered per minute across six velocity-based intensity zones (km/h): total distance, walking (<7.2), jogging (7.2-14.3), running (14.3-19.8), high-speed running (19.8-25.2), and sprinting (>25.2). Match-to-match variability was calculated using the coefficient of variation (CV%). A linear mixed-effects model examined the influence of intensity zone and playing position on match-to-match variability, including their interaction.
RESULTS:
Mean running demands ranged from 119.0 ± 8.5 m·min⁻¹ (total distance) to 2.2 ± 1.0 m·min⁻¹ (sprinting). CV% was 4.5 ± 0.9% for total distance and did not differ for walking (β = −0.38, p = 0.774). Variability was greater for jogging (8.0 ± 1.7%; β = 3.54), running (12.4 ± 2.6%; β = 8.59), high-speed running (18.2 ± 3.9%; β = 15.99), and sprinting (39.4 ± 13.7%; β = 40.26) compared with total distance (all p ≤ 0.007). No significant main effects of position were observed (all p > 0.80); however, significant intensity × position interactions were found for high-speed running in AM (β = −4.97, p = 0.008) and sprinting across multiple positions (AM, FB, CF vs CB; all p ≤ 0.001), with the largest difference in FB (β = −11.72, p < 0.001). Between-player differences accounted for small variance (ICC = 0.09).
CONCLUSION:
Match-to-match variability in running demands increased substantially with intensity zone, with positional differences emerging only in high-speed running and sprinting. These findings highlight the need for zone- and position-specific consideration in player match-load quantification, given the substantially greater match-to-match variability in high-intensity metrics compared with total distance.

References:
1. Carling C, Bradley P, McCall A, Dupont G. Match-to-match variability in high-speed running activity in a professional soccer team. J Sports Sci. 2016;34(24):2215-2223
2. Teixeira JE, Branquinho L, Leal M, et al. Match-to-Match variation on High-Intensity demands in a Portuguese professional football team. J Funct Morphol Kinesiol. 2024;9(3):120