Introduction:Post-COVID rehabilitation has favourable effect in terms of cardiovascular response, metabolism, peripheral muscle function and lung mechanics. The length of rehab is questionable.
Patients and Methods: 15 post-COVID patients (AVE±SD, male:female= 8:7 , age: 53.2±11.6 years, BMI: 31.4±7.7 kg/m2, FEV1: 82±3 ref% performed cardiopulmonary exercise testing 2 and 3 months after the start of rehabilitation treatment. The post-COVID patients initially received respiratory exercise, learning controlled breathing techniques and chest mobilization in a day hospital program, and endurance training in the form of bicycle conditioning or treadmill conditioning for 1x10-30 min daily, after which they continued the learned exercises at home according to prior instructions. The physiological changes of the patients were monitored by cardio-pulmonary exercise testing of maximal exercise capacity, oxygen uptake, lactate threshold and minute ventilation response.    
Results: Exercise physiological parameters changed as follows (IQR, 2 vs. 3 months): peak work capacity (WR) 113 (86-140) vs. 141 (101-155) W, p=0.306; VO2: 1192 (1093-1283) vs. 1403 (1175-1731) ml/min, p=0.395; VCO2: 1457 (1296-1555) vs. 1667 (1442-2063) ml/min, p=0.474; metabolic ratio (RER): 1.21 (1.13-1.26) vs. 1.16 (1.13-1.22), p=0.244; VEmax: 46.3 (42-59) vs. 55.6 (46-71) L/min, p=0.582.
Conclusion: Extension of post-COVID rehabilitation from 2 to 3 months showed a positive trend in WR and VO2, further case number and data analysis is needed to assess the exact physiological response.