Introduction The first aim of this study was to compare synchronous and asynchronous telerehabilitation programs in COVID-19 survivors with classes 4–6 and determine the more appropriate telerehabilitation approach. Methods Thirty-six COVID-19 survivors with class 4–6 severity were randomly divided into two groups. Telerehabilitation programs were an 8-week exercise program that comprised pulmonary, aerobic, and strengthening exercises. Patients were assessed at the baseline, post-treatment, and follow-up for the incremental shuttle walk test (ISWT), short physical performance battery (SPPB), health-related quality of life (HRQoL) and hospital anxiety and depression scale (HADS) Results The overall mean age of the study population was 54.06 (SD 10.50), and 15 (46.8%) were male. There were no significant differences between the two groups in any of the demographics and clinical characteristics at the baseline (p > 0.05), except for physical function (p < 0.05). There was a significant improvement in exercise capacity (p < 0.001) and lower extremity function (p < 0.01) within both groups in the short term and long term. There was a significant improvement in some subparameters of quality of life in both groups. As the synchronous group's short-term and long-term psychological status improved significantly, the asynchronous group's short-term psychological status improved significantly (p < 0.05). Telerehabilitation programs had similar effects, and only synchronous telerehabilitation outperformed asynchronous telerehabilitation in terms of physical function, role-emotional, and long-term anxiety. Discussion Asynchronous telerehabilitation was as effective as synchronous telerehabilitation in developing clinical and functional parameters when properly planned and implemented.