Effects of Respiratory Muscle Training in Individuals With Long-term Post-COVID-19 Symptoms

Effects of Respiratory Muscle Training Combined With an Exercise Training Program in Individuals With Long-term Post-COVID-19 Symptoms

The main objective of the present study is to observe the short-term effects of respiratory muscle training combined with an exercise training program on quality of life and exercise tolerance in individuals with long-term post-COVID-19 symptoms. As secondary objectives, the effects on respiratory muscle function, physical and lung function, as well as on the psychological state of these individuals.

It is a double-blind randomized clinical trial study. Each participant will be randomly assigned to one of the following groups: 1) Exercise training program + Inspiratory muscle training + Expiratory muscle training, 2) Exercise training program + Sham Inspiratory muscle training + Sham Expiratory muscle training. The exercise training program will be delivered in hospital and will be applied 2 sessions per week during 8 weeks. The exercise component will be lasted for 1hour and it consisted of cardiovascular exercises. The respiratory muscle training program will be applied twice a day, 3 sessions per week during 8 weeks by a threshold device. The evening sessions will be supervised by a physiotherapist through a virtual platform. Participants received baseline assessments at the beginning of the intervention and post-intervention assessments at the end of the 8th week.

Participants will perform a cardiovascular exercise program 2 days per week during 8 weeks in the hospital, combined with an inspiratory and expiratory muscle training by a threshold device at home, twice a day, 3 days per week, for 8 weeks supervised by a physiotherapist through a virtual platform.

Participants will perform a cardiovascular exercise program 2 days per week during 8 weeks in the hospital, combined with an inspiratory and expiratory muscle training by a sham threshold device at home, twice a day, 3 days per week, for 8 weeks supervised by a physiotherapist through a virtual platform.

Participants will perform an inspiratory and expiratory muscle training including warm-up, recovery between intervals and return to calm.

Participants will perform an inspiratory and expiratory muscle training including warm-up, recovery between intervals and return to calm.

Participants will perform a cardiovascular exercise program including warm-up, recovery between intervals and return to calm by cycloergometer.

Change in quality of life between baseline and post-intervention, as measured by the EuroQol-5D questionnaire which consists of 5 dimensions with 5 response options based on severity level, ranging from 1 to 5. An index score is provided, ranging from 0 (death) to 1 (full health).

Change in exercise tolerance between baseline and post-intervention, as measured by a cardiopulmonary exercise test

Change in inspiratory/expiratory muscle strength and inspiratory muscle endurance between baseline and post-intervention, as measured by maximum static inspiratory and expiratory pressures and by a constant load breathing test

Change in lower and upper limb strength between baseline and post-intervention, as measured by 1-min Sit-to-Stand and peripheral muscle force (dynamometry)

Change in pulmonary function and diffusion capacity for carbon monoxide between baseline and post-intervention, as measured by pulmonary function tests

Change in anxiety/depression levels between baseline and post-intervention, as measured by Hospital Anxiety and Depression Scale

Inclusion Criteria: Over 18 years who presented long-term post-COVID-19 symptoms of fatigue and dyspnoea for at least 3 months after the COVID-19 diagnosis Exclusion Criteria: Progressive respiratory, neuromuscular or neurological disorders and/or psychiatric or cognitive conditions that hindered their ability to cooperate Comorbidity that could interfere with the study interventions Any contraindication to the training interventions Previous inclusion in a rehabilitation program for their long-term post-COVID-19 symptoms (previous 3 months)

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Nopp S, Moik F, Klok FA, Gattinger D, Petrovic M, Vonbank K, Koczulla AR, Ay C, Zwick RH. Outpatient Pulmonary Rehabilitation in Patients with Long COVID Improves Exercise Capacity, Functional Status, Dyspnea, Fatigue, and Quality of Life. Respiration. 2022;101(6):593-601. doi: 10.1159/000522118. Epub 2022 Feb 24.