The pandemic of COVID-19 has caused public health-related, and economic consequences regarding lifestyles. Due to social distancing strategies, physical inactivity has increased in various societies, which might lead to an increase in the burden of non-communicable diseases in long term. The health benefits of physical activity consist of a wide range, including physical, mental, and social dimensions. Therefore, this book discusses whether engaging in regular physical activity is effective in preventing COVID-19 infection, reducing the severity of symptoms, reducing mortality, or eliminating COVID-19 complications. The book will serve as a practical guideline for public health experts and physicians. It covers COVID-19 and physical inactivity prevalence in different regions, physical activity and risk of COVID-19 infection, physical activity and course of COVID-19 infection including disease severity, hospitalization rate, ICU admission, and mortality, physical activity as a vaccine booster in different populations, post- COVID-19 physical rehabilitation, and strategies for enhancing physical activity in the COVID-19 pandemic.