562 EP060 – Shed Light on the SARS-CoV-2 Infection decreases cardiorespiratory fitness and time-trial performance – insights from a longitudinal case series of well-trained young Kayakers

Background The effects of acute respiratory infections (ARinf) on cardiorespiratory fitness (CRF) and sports performance still mixed outcomes and remain significant methodological heterogeneity. The current situation has become more unclear by elements encompassing vaccination, the appearance of new variants, and more open guidelines for return-to-sport (RTS). Objective The aims of this study were to verify the causality of SARS-CoV-2's effects on CRF and 1000-m time-trial (TT) performance in vaccinated well-trained young kayakers. Design Longitudinal observational study. Setting Professional training center, well-trained, nation-level. Participants 16 (56convertpEsc2Char: error FE! male) vaccinated sprint kayakers (17.6 ± 1.6 yrs, 175.8 ± 7.2 cm) underwent maximal graded exercise test, and 1000-m TT tests 21.9 ± 1.7 days before and 66.0 ± 2.2 days after the SARS-CoV-2 infection (Omicron variant). Independent variables:1) CRF: peak oxygen uptake (VO2peak), peak oxygen/heart rate (peak O2 pulse), peak heart rate (HRpeak), peak minute ventilation (VEpeak), minute ventilation/carbon dioxide production slope (VE/VCO2 slope), peak end-tidal carbon dioxide pressure (PETCO2peak), and peak respiratory exchange ratio (RERpeak); 2) 1000-m TT performance: completion time (CT), mean power output (MP), mean speed (MS), stroke rate (SR), and stroke length (SL) analyzed as the entire 1000-m, and per 250-m splits. Main Outcome Measurements CRF & 1000-m TT test (MetaMax 3B, Cortex, Leipzig, Germany) & (Dansprint ApS, Hvidovre, Denmark). Results 1) There were significant decreases in VO2peak, peak O2 pulse, and HRpeak as well as no significant changes in VEpeak, and VE/VCO2 slope, but PETCO2peak and RERpeak were significantly increased after infection. Parameters of the TT performance were significantly impaired after infection. Conclusions Even mild SRAS-CoV-2 infection significantly decreased CRF and TT performance in vaccinated athletes. This is mainly attributed to impaired peripheral/mitochondrial mechanisms, rather than central mechanisms (cardiopulmonary). These results were beneficial in developing more targeted treatment prescriptions, preventive interventions, and RTS strategies in athletes after Arinf.