Pengembangan Model Telerehabilitasi untuk Pasien Long COVID: Efektivitas terhadap Kapasitas Fungsional, Kualitas Hidup, Stres Oksidatif, dan Disfungsi Endotel = Development of Telerehabilitation Model for Long COVID Patients: Effectiveness on Functional Capacity, Quality of Life, Oxidative Stress, and Endothelial Dysfunction