Data from medical records of 144 COVID-19 patients who had completed inpatient treatment were analyzed, as well as the results of the subsequent survey using a modified questionnaire. The relationship between physical activity level, performance, quality of life (prior to infection and after treatment), age, therapeutic exercises execution rate while staying in the hospital, stool problems, high blood pressure episodes after treatment, and the course of the disease was evaluated. The patients were divided into a control and experimental group in accordance with the the initial subjective level of performance. The moderate form of the disease prevailed (69.44%). The mild form was typical for younger patients, the patients over 50 years of age made up 62.49% of the total number of severe cases. Severe patients reported lower quality of life and performance prior to the disease compared to those with moderate and mild course of the infection. The patients (mild and moderate cases) with more active initial lifestyle and higher initial performance who practiced therapeutic exercises while staying in the hospital had a more favorable course of the disease (reduced length of stay in a hospital, fast recovery of performance, reduced number of CT scans). The higher initial physical activity level contributed to milder course of the infection. It is necessary to raise public awareness, especially among the elderly, about the regular physical activity benefits and the correlation between physical activity level and the course of the disease, as well as to introduce exercise therapy at all treatment stages.