Short-term effects of SARS-CoV-2 infection and return to sport on neuromuscular performance, body composition, and mental health - A case series of well-trained young kayakers

Abstract

Purpose: This study aimed to examine the short-term effects of SARS-CoV-2 infection and return to sport (RTS) on neuromuscular performance, body composition, and mental health in well-trained young kayakers.

Methods: 17 vaccinated kayakers (8 male, 9 female) underwent body composition assessment, peak power output bench press (BP), and 40-s maximum repetition BP tests 23.9 ± 1.6 days before and 22.5 ± 1.6 days after a SARS-CoV-2 infection. A linear transducer was used to examine the BP performance. The perception of training load and mental health were quantified with Borg's CR-10 scale and the Hooper questionnaire before and after infection. The difference and relationship of variables were used Wilcoxon test, Student t-test, Pearson's, and Spearman's r correlation coefficients.

Results: There was a significant increase in body mass, fat-free mass, and skeletal muscle mass, but no significant changes in body fat, fat mass, and all BP performance after infection (p < 0.05). There was a significant reduction in training hours per week, session rating of perceived exertion (sRPE), internal training load (sRPE-TL), fatigue, muscle soreness levels, and Hooper index, but no changes in sleep quality and stress levels after infection (p < 0.05). The training and mental health during the RTS period was significantly correlated (r = -0.85 to 0.70) with physical performance after infection.

Conclusion: A SARS-CoV-2 infection did not appear to impair the upper-body neuromuscular performance and mental health of vaccinated well-trained young kayakers after a short-term RTS period. These findings can assist coaches, and medical and club staff when guiding RTS strategies after other acute infections or similar restrictions.

Keywords: Acute respiratory infection; Athletes; COVID-19; Physical performance; Rehabilitation; Return to play.

Fig. 1

Timeline and data collection. The number in circles denotes sequences of the testing procedure. Number 1, body composition analysis; Number 2, neuromuscular performance test; Number 3 and 6, daily collected training load and mental health; Number 4, COVID-19 specific questionnaire; Number 5, blood pressure and SpO₂. Each colored block denotes different periods. Abbreviation: SARS-CoV-2, severe acute respiratory syndrome coronavirus 2; RTT, return to training; RTS, return to sport.

Fig. 2

Training routine followed by the kayakers during the pre- and post-infection RTS period. Abbreviation: END, endurance training; HIIT, high-intensity interval training; RT, resistance training; BFR, blood flow restriction, 1-RM, one-repetition maximum, RTS, return to sport. Note: no difference in compliance with the training sessions during two periods (97.2 ± 5.8 vs 96.8 ± 9.0 [%]).

Fig. 3

The prevalence of self-reported symptoms in athletes infected with SARS-CoV-2.

Fig. 4

The perception of training intensity (session rating of perceived exertion [sRPE]) performed during the pre- and post-infection RTS period (A); Pre- and post-test BP performance data (B). Bars denote mean values, and dots and lines denote individual changes. sRPE (AU) were divided into 3 zones as low (≤4), moderate (5–6), and high (≥7). Abbreviation: RTS, return to sport; Δ%, relative changes, ES, effect size; BP, bench press; 40-s, 40-s; PP, peak power output; MP, mean power output. ∗p < 0.05.