Training the respiratory muscles is a crucial aspect of pulmonary rehabilitation. The purpose of this study was to assess the function of respiratory muscles in older adults both before and after a period of pulmonary rehabilitation and treatment stay within the underground chambers of a salt mine. A total of 50 patients aged 65 years and older with chronic respiratory conditions was enrolled in the study. These participants underwent a 3-week subterranean pulmonary rehabilitation (PR) program in the "Wieliczka" Salt Mine. Levels of sniff nasal inspiratory pressure (SNIP), maximum inspiratory pressure (MIP), and maximum expiratory pressure (MEP) were measured using the MicroRPM both before and after the outpatient PR program conducted 135 m underground. A total of 44 patients with a mean age of 68.8 ± 2.9 years who completed the PR program and tests were included in the analysis. The average changes in the parameters of pulmonary function before and after the PR were: MIP 8.8 cmH2O, MEP 7.1 cmH2O, and SNIP 11.2 cmH2O (for p < 0.05). For patients older than 70 years, beneficial changes were only observed for MEP, which increased by 9.3 cmH2O (for p < 0.05). Speleotherapy combined with pulmonary rehabilitation improves respiratory muscle function in older adults with chronic respiratory diseases, mainly in terms of MEP. Therefore, a greater emphasis on inspiratory muscle training in the rehabilitation program should be considered.
Keywords: diaphragm; maximum expiratory pressure; maximum inspiratory pressure; sniff nasal inspiratory pressure; speleotherapy; subterraneotherapy; the elderly.