Statistically significant lower risk is seen for mortality, ventilation, ICU admission, hospitalization, progression, recovery, and cases. 51 studies from 51 independent teams in 24 countries show statistically significant improvements.
Meta analysis using the most serious outcome reported shows 39% [34‑44%] lower risk. Results are similar for higher quality and peer-reviewed studies.
Results are robust — in exclusion sensitivity analysis 54 of 66 studies must be excluded to avoid finding statistically significant efficacy in pooled analysis.
Results are consistent with the overall risk of all cause mortality based on cardiorespiratory fitness — Laukkanen show RR 0.55 [0.50-0.61] for the top vs. bottom tertiles.
Most studies analyze exercise/physical activity levels before infection, comparing regular/moderate exercise and lower/no exercise. Risk may increase with more extreme activity levels.
No treatment or intervention is 100% effective. All practical, effective, and safe means should be used based on risk/benefit analysis.
All data to reproduce this paper and sources are in the appendix. Other meta analyses show significant improvements with exercise for mortality Ezzatvar, Halabchi, Liu, Rahmati, Sittichai, ICU admission Rahmati, hospitalization Ezzatvar, Halabchi, Li, Rahmati, severity Ezzatvar, Liu, Sittichai, and cases Ezzatvar.
6 meta analyses show significant improvements with exercise for mortality
Ezzatvar,
Halabchi,
Liu,
Rahmati,
Sittichai,
ICU admission
Rahmati,
hospitalization
Ezzatvar,
Halabchi,
Li,
Rahmati,
severity
Ezzatvar,
Liu,
Sittichai, and
cases
Ezzatvar.
Covid Analysis et al., Mar 2024, preprint, 1 author.