The exercises were conducted at a heart rate of 50-70% of maximum heart rate for 30 minutes. Exercises were included strengthening muscles groups (shoulder flexors, extensors, abductor's muscles, hip flexors, extensor muscles, knee flexors, extensor muscles, abdominal muscles, and back muscles).

Exercises were performed at 40-50% of the maximum heart rate Starting by 15 minutes of Warm-up time included static stretching of upper and lower body muscles.

After that, participants performed 30 minutes of low-intensity aerobic training exercises, which included 20 minutes on the treadmill, followed by 10 minutes of cooling down.

A set of 5-10 exercises was performed by each muscle group, three sets per exercise were performed, and 10-15 repetitions per series were performed 4 days per week

participants will perform different dosage of the same intervention, one group will perform moderate intensity and the other will perform low intensity aerobic training

The 6-min walk test (6 MWT) measures the distance that a patient can quickly walk on a flat, hard surface in a period of 6 minutes (the 6MWD). (ATS Statement: Guidelines for the Six-Minute Walk Test, Am J Respir Crit Care Med, 2002)

This scale measures the functional state and Independence of patients after COVID-19 infection. The scale includes two items scored from 0-4 and 0-5. A high value indicates more restrictions in function and independence during daily life.

All 1-min STS tests are performed according to a standardized protocol by trained study staff. A standard chair is used with a flat seat and no armrests, stabilized against a wall. Patients are asked to sit with their legs hip-width apart and flexed to 90°, with their hands stationary on the hips.