The Effects of Exercise Training on Recovery of Biochemical and Hematological Outcomes in Patients Surviving COVID-19: A Randomized Controlled Assessor-Blinded Trial

BACKGROUND: No previous research has investigated the direct effects of exercise interventions on COVID-19 outcomes. The aim is to investigate the effect of 8 weeks of home-based moderate-intensity continuous training (MICT), resistance training (RT), and combined aerobic and resistance training (CET) on biochemical and hematologic markers associated with COVID-19 symptoms and severity in COVID-19 survivors. METHODS: A total of 547 male and female COVID-19 survivors were screened, and 296 (aged 20–93 years) were randomly assigned in a 1:1:1:1 ratio to one of four groups: MICT (n = 74), RT (n = 74), CET (n = 74), or non-exercise (NON-EX, n = 74). Blood samples were taken at baseline, at week 4, and week 8 after training. RESULTS: After the intervention, compared with the NON-EX group, all 3 MICT, RT, and CET interventions caused significant improvements in the levels of creatine kinase (CK), lactate dehydrogenase (LDH), C-reactive protein (CRP), troponin-I, d-dimer, creatinine, urea, potassium (K), sodium (Na), white blood cell (WBC), neutrophils, lymphocytes, red blood cells (RBC), platelets, hemoglobin, and hematocrit concentrations (P < 0.05). CET was effectively superior to MICT and RT in the improvements in the biochemical and hematological variables studied (P < 0.05). CONCLUSIONS: Overall, the present study demonstrates that long-term MICT plus RT interventions have a synergistic effect in accelerating and enhancing the recovery in patients surviving COVID-19. Trial registration IRCT20160605028270N3, 6 September 2020. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s40798-022-00546-4.