Covid-19 transmission in fitness centers in Norway - a randomized trial
AuthorHelsingen, Lise Mørkved; Løberg, Magnus; Refsum, Erle; Gjøstein, Dagrun Kyte; Wieszczy, Paulina; Olsvik, Ørjan; Juul, Frederik Emil; Barua, Ishita; Jodal, Henriette C.; Herfindal, Magnhild; Mori, Yuichi; Jore, Solveig; Lund-Johansen, Fridtjof; Fretheim, Atle; Bretthauer, Michael; Kalager, Mette
Methods: In a two-group parallel randomized controlled trial, fitness center members aged 18 to 64 without Covid-19-relevant comorbidities, were randomized to access to training at a fitness center or no-access. Fitness centers applied physical distancing (1 m for floor exercise, 2 m for high-intensity classes) and enhanced hand and surface hygiene. Primary outcomes were SARS-CoV-2 RNA status by polymerase chain reaction (PCR) after 14 days, hospital admission after 21 days. The secondary endpoint was SARS-CoV-2 antibody status after 1 month.
Results: 3764 individuals were randomized; 1896 to the training arm and 1868 to the no-training arm. In the training arm, 81.8% trained at least once, and 38.5% trained ≥six times. Of 3016 individuals who returned the SARSCoV-2 RNA tests (80.5%), there was one positive test in the training arm, and none in the no-training arm (risk difference 0.053%; 95% CI − 0.050 to 0.156%; p = 0.32). Eleven individuals in the training arm (0.8% of tested) and 27 in the no-training arm (2.4% of tested) tested positive for SARS-CoV-2 antibodies (risk difference − 0.87%; 95%CI − 1.52% to − 0.23%; p = 0.001). No outpatient visits or hospital admissions due to Covid-19 occurred in either arm.
Conclusion: Provided good hygiene and physical distancing measures and low population prevalence of SARS-CoV-2 infection, there was no increased infection risk of SARS-CoV-2 in fitness centers in Oslo, Norway for individuals without Covid-19-relevant comorbidities