COVID‐19 disease in professional football players: symptoms and impact on pulmonary function and metabolic power during matches

<jats:title>Abstract</jats:title><jats:p>This study aimed at: (1) Reporting COVID‐19 symptoms and duration in professional football players; (2) comparing players’ pulmonary function before and after COVID‐19; (3) comparing players’ metabolic power (P<jats:sub>met</jats:sub>) before and after COVID‐19. Thirteen male players (Age: 23.9 ± 4.0 years, V̇O<jats:sub>2peak</jats:sub>: 49.7 ± 4.0 mL/kg/min) underwent a medical screening and performed a running incremental step test and a spirometry test after COVID‐19. Spirometric data were compared with the ones collected at the beginning of the same season. Players’ mean P<jats:sub>met</jats:sub> of the 10 matches played before COVID‐19 was compared with mean P<jats:sub>met</jats:sub> of the 10 matches played after COVID‐19. Players completed a questionnaire on COVID‐19 symptoms and duration 6 months following the disease. COVID‐19 positivity lasted on average 15 ± 5 days. “General fatigue” and “muscle fatigue” symptoms were reported by all players during COVID‐19 and persisted for 77% (general fatigue) and 54% (muscle fatigue) of the players for 37 ± 28 and 38 ± 29 days after the disease, respectively. No significant changes in spirometric measurements were found after COVID‐19, even though some impairments at the individual level were observed. Conversely, a linear mixed‐effects model analysis showed a significant reduction of P<jats:sub>met</jats:sub> (−4.1 ± 3.5%) following COVID‐19 (<jats:italic>t</jats:italic> = −2.686, <jats:italic>p</jats:italic> &lt; 0.05). <jats:bold>“</jats:bold>General fatigue” and “muscle fatigue” symptoms may persist for several weeks following COVID‐19 in professional football players and should be considered for a safer return to sport. Players’ capacity to compete at high intensities might be compromised after COVID‐19.</jats:p>