The Effect of the Number of Substitutions on Running Activity in Professional Football Matches: An Observational Study from the Swiss Super League

This study aimed to compare the running activity of full-time players when the team made three or fewer substitutions versus when more than three substitutions were made. An observational study was conducted on one professional football team from the Swiss Super League during the 2021–2022 season. Matches were classified into two groups: Group A (≤3 substitutions) and Group B (>3 substitutions). Running activity was assessed using GPS technology, measuring total distance covered, sprinting distance, and acceleration/deceleration patterns. Despite a significantly higher number of substitutions in Group B (4.42 ± 0.51 vs. 2.8 ± 0.42, p < 0.01), no differences were observed between groups for all parameters analyzed (p > 0.05). Both groups exhibited significantly higher running performance during the first half compared to the second half (p < 0.01), except for distance covered > 25.2 km·h−1, which remained unchanged (p > 0.05). No differences in second half running performance were found between groups (p > 0.05). The increase from three to five substitutions did not significantly alter the external load of full-time players. Running performance declined in the second half regardless of the number of substitutions made. These findings suggest that the new substitution rule does not influence the physical performance of players who complete the entire match.