Efficacy of respiratory muscle training on respiratory function and quality of life in various respiratory conditions: A systematic review

Respiratory muscle training (RMT) has emerged as a promising intervention for improving respiratory function and quality of life in individuals with various respiratory conditions, including chronic obstructive pulmonary disease (COPD) and asthma. This review synthesizes findings from several studies investigating the effects of RMT on respiratory muscle strength, exercise capacity, dyspnea, and quality of life. Studies employing different RMT protocols, including inspiratory muscle training (IMT), expiratory muscle training (EMT), and combined training, demonstrate consistent improvements in key outcomes. Significant increases in maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) reflect enhanced respiratory muscle strength. Improvements in 6-minute walk test (6MWT) distance and reductions in dyspnea scales (e.g., mMRC, Borg) indicate enhanced exercise tolerance and reduced breathlessness. Furthermore, studies utilizing quality of life questionnaires (e.g., SGRQ) suggest positive impacts on overall well-being. While variations exist in training protocols and patient populations, the collective evidence supports the integration of RMT into pulmonary rehabilitation programs for individuals with respiratory conditions. Future research should focus on optimizing RMT protocols and exploring the long-term effects of this intervention.