Internal and external match loads of university-level soccer players: a comparison between methods

Abstract

The aim of this study was to use individualized intensity zones to compare the external (velocity and Player Load, PL) and internal loads (heart rate, HR) of a cohort of university-level soccer players. Thirteen soccer players completed a 40 m maximum speed test and the Yo-Yo Intermittent Recovery Test 1 (Yo-Yo IR1) to determine individualized velocity and HR thresholds. HR values and global positioning system (GPS) data of each player were recorded during five league matches. A large (r = 0.46; p ≤0.01) correlation was found between time spent in the low-intensity (LI) velocity zone (LIVZ) and the LI HR zone. Similarly, there were moderate (r = 0.25; p ≤0.01) to large (r = 0.57; p ≤0.01) correlations between the relative and absolute time spent in the moderate-intensity (MI) velocity zone (MIVZ) and the MI HR zone. No significant correlations (p ≤0.01) existed between the high-intensity (HI) velocity zones (HIVZ) and the HI HR zone. On the other hand, PL showed significant correlations with all velocity and HR (absolute and relative) variables, with the exception of an non-significant correlation between the HI HR variables and PL. To conclude, PL showed good correlations with both velocity and HR zones and therefore may have the potential to serve as a good indicator of both external and internal soccer match loads.