How long is the long COVID? a retrospective analysis of football players in two major European Championships.

Objectivesthe goal of this study was to investigate the correlation between SARS-CoV-2 infection and muscle injuries among a large sample of professional soccer players. MethodsA retrospective cohort study was conducted on professional soccer players from the Serie A and LaLiga leagues during the 2019-2020 and 2020-2021 football seasons. The players were divided into two groups based on whether they contracted the Sars-CoV-2 infection (C+) or not (C-) during the 2020/2021 season. Data collection was conducted using the Transfermarkt24 site. ResultsIn the 2019-2020 both championships showed non-significant differences in the average number of muscular injuries between the C+ group and the C- group (Serie A: p=0.194; 95%CI: - 0.044 to 0.215, LaLiga p=0.915; 95%CI: -0.123 to 0.137). In the 2020-2021 the C+ group had a significantly higher number of muscular injuries compared to the C- group in both championships (Serie A: p<0.001; 95%CI 0.731 to 1.038; LaLiga: p<0.001; 95%CI: 0.773 to 1.054). Multiple linear regression analysis confirmed that belonging to C+ in the season 2020/2021 was the variable that most strongly influenced the probability of having a muscle injury in both championships. Survival analysis revealed a hazard ratio of 3.73 (95%CI 3.018 to 4.628) and of 5.14 (95% CI 3.200 to 8.254) for Serie A and LaLiga respectively. ConclusionsThis retrospective cohort study revealed a significant association between SARS-CoV-2 infection and increased risk of muscle injury, emphasizing the importance of carefully considering the infection in the decision-making process for determining athletes readiness to return to sport.