Weekly variations of biomechanical load variables in professional soccer players: comparisons between playing positions

Abstract

PurposeThe purpose of the present study was fourfold: (i) to describe the weekly variations of acute external load measures during a professional soccer season; (ii) to analyse the variability of external load measures within weeks; (iii) to analyse the acute:chronic workload ratio of players during the process; and (iv) to analyse the differences of external load measures between playing positions.MethodsTwenty professional soccer players (age: 24.9 ± 3.5 years; body mass: 71.6 ± 18.7 kg; height: 168.8 ± 41.4 cm) from the same team competing in the First Portuguese League (Europe) voluntarily participated in this study. They were daily monitored with a Global Positioning System (GPS) and the following external load variables were extracted per session: (i) total distance; (ii) running distance; (iii) high-speed running distance; (iv) distance at maximal speed; (v) distance at high accelerations; and (vi) players’ training load. The acute load and acute:chronic workload ratio were weekly calculated for each of the GPS measures.ResultsWeek-by-week variations ranged from –57% to +115%, depending on the playing position and the variable measured. The within-week variability revealed coefficients of variation between 48% and 55%, depending on the measure. Considering the differences in mean load between playing positions, significant differences between players were found for the majority of the variables, with the only exceptions being maximal speed and high accelerations distances.ConclusionsGreat between-week variations in the acute load as well as the variability of load within weeks were found. It was observed that acute load was position-dependent.