Effectiveness of Functional Respiratory Muscle Training in Post-COVID-19 Syndrome

Investigation of the Effects of Functional Respiratory Muscle Training on Respiratory Muscle Function, Exercise Capacity, Skeletal Muscle Strength, and Muscle Endurance in Individuals With Post-COVID-19 Syndrome

This study aims to investigate the effects of core stabilization exercises and functional inspiratory muscle training (IMT) on various physiological and psychological parameters in individuals with post-COVID-19 syndrome. Participants diagnosed with post-COVID-19 syndrome will be randomly assigned to two groups using stratified computer-assisted randomization. One group will undergo an 8-week core stabilization training, while the other will receive combined core stabilization and IMT training. Exercise training will be conducted three times a week, with each session lasting 50 minutes.

Comprehensive pre- and post-intervention assessments will be conducted, including exercise capacity, respiratory and peripheral muscle strength, trunk endurance, balance, anxiety, depression, and fatigue levels. The primary outcome measures are respiratory muscle strength and trunk endurance.

Participants must be aged 18-65 years, have at least a primary education level, speak Turkish, and be classified as level 2-3 on the Post-COVID-19 Functional Status Scale (PCFS). Eligible participants will be referred by the Internal Medicine Department at Hacettepe University.

The study will utilize various assessment tools, including maximal inspiratory/expiratory pressure (MIP/MEP) tests, Functional Movement Screen (FMS), plank and Sorenson endurance tests, the Timed Up and Go Test for balance, handgrip and knee extension strength tests, body composition analysis, and the SF-36 quality of life questionnaire.

This study aims to investigate the effects of core stabilization programs supported by core stabilization exercises and functional inspiratory muscle training (IMT) on various physiological and psychological parameters in individuals with post-COVID-19 syndrome.

Participants to be included in the study will consist of individuals diagnosed with post-COVID syndrome and will be divided into two groups with a computer-aided stratified randomization method.

After the patients are randomly separated, one group will receive 8 weeks of core stabilization training and the other group will receive functional IMT (IMT combined with core stabilization) training. The exercise program is designed to last 8 weeks in total, and the training program for both groups will be carried out on certain days (3 days) per week, and each session will last 50 minutes.

A comprehensive assessment will be applied to both groups at the beginning and end of the study. These assessments are; exercise capacity, respiratory muscle strength, peripheral muscle strength, trunk muscle endurance, balance, anxiety and depression levels, and fatigue level parameters. The primary outcome measure of the study will be respiratory muscle strength and trunk muscle endurance.

Individuals who meet the inclusion criteria will be included in the study. The study will be conducted with individuals between the ages of 18-65, with at least primary school education, and whose local language is Turkish. Participants diagnosed with Post-COVID-19 Syndrome and who are in class 2-3 according to the Post-COVID-19 Functional Status Scale (PCFS) will be included in the study. Participants who are eligible for the study will be directed to the Cardiopulmonary Rehabilitation Unit of the Hacettepe University Faculty of Physical Therapy and Rehabilitation by the relevant physicians of the Department of General Internal Medicine of the Hacettepe University Department of Internal Medicine.

Inclusion Criteria:

• Diagnosed with Post-COVID-19 Syndrome.
• Literate and able to understand study procedures.
• Aged between 18 and 65 years.
• Willing to voluntarily participate in the study.
• Classified as functional class 2-3 according to the Post-COVID-19 Functional Status Scale (PCFS).
• Clinically stable; comorbid conditions such as hypertension or diabetes must be controlled.
• No orthopedic or neurological conditions that would prevent assessment of peripheral muscle strength, balance, or exercise capacity.

Exclusion Criteria:

• History of recent myocardial infarction or pulmonary embolism.
• Presence of uncontrolled chronic diseases.
• Any orthopedic or neurological disorders that limit mobility.
• Neurological impairments (e.g., cerebrovascular disease) or psychiatric disorders that impair cooperation or compliance with exercise testing.