Inclusion Criteria:  For cases with COVID-19:  Confirmed COVID-19 infection - For healthy individuals of the same age group who have not had COVID-19: Individuals who have not been diagnosed with COVID-19 as of March 11, 2020 and who have not been in contact and risky according to the "Life Fits Into Home" application  - For all participants; Answering "No" to all questions in the Physical Activity Readiness Questionnaire.  Exclusion Criteria:  Individuals with orthopedic or neurological disabilities that may interfere with exercise testing, Individuals with a fever> 38 ° C and / or resting blood pressure <90/60 mmHg or> 140/90 mmHg and/or oxygen saturation ≤95%, Individuals who have been involved in a physiotherapy and rehabilitation program within the last 3 months, Individuals with insufficient cooperation Individuals with blood coagulation disorders contraindicated for blood lactate analysis, Pregnant women or individuals with suspected pregnancy