Comparative effectiveness of progressive moderate- to high-intensity peripheral and inspiratory muscle training combined with aerobic exercise in community-dwelling older adults: A randomized clinical trial

Background: This study aims to compare the effects of moderate- to high-intensity peripheral and inspiratory muscle training, when combined with aerobic training, on muscle strength, respiratory muscle strength, physical performance, functional capacity, sarcopenia, and quality of life in older adults. Methods: Thirty-four community-dwelling older adults were randomly assigned to either the peripheral muscle training (PMT) group (n = 17) or the inspiratory muscle training (IMT) group (n = 17). Participants in the PMT group performed resistance training targeting both the upper and lower extremities at 60 to 80% of their one-repetition maximum (1RM). In contrast, the IMT group engaged in IMT at 60 to 80% of their baseline maximum inspiratory pressure (MIP), using a threshold IMT device. Both groups additionally participated in supervised step-aerobic sessions twice weekly for 10 weeks, aiming for 50 to 70% of their individual maximum heart rate. Outcome measures included hand grip strength, MIP, maximum expiratory pressure (MEP), the 6-minute walk test (6-MWT), the Short Physical Performance Battery (SPPB), the SARC-F questionnaire, and the World Health Organization Quality of Life Instrument-Older Adults Module (WHOQOL-OLD). All assessments were conducted at baseline and repeated after completion of the 10-week training program in both groups. Results: Between-group comparisons of pre- to post-intervention changes revealed a significant difference in the WHOQOL-OLD death and dying subscale, with greater improvement observed in the IMT group ( P = .019, d = 0.185). In the PMT group, significant post-intervention increases were observed in MEP ( P = .003, d = 0.876), MEP% ( P = .002, d = 0.932), 6-MWT ( P = .001, d = 0.974), and the WHOQOL-OLD sensory abilities subscale ( P = .035, d = 0.528). In the IMT group, significant improvements were noted in MIP ( P = .002, d = 0.788), MIP% ( P = .001, d = 1.032), 6-MWT ( P = .003, d = 0.889), and the WHOQOL-OLD death and dying subscale ( P = .040, d = 0.564). Conclusion: This study demonstrates that moderate- to high-intensity PMT and IMT, when combined with aerobic training, significantly enhances respiratory muscle strength, functional capacity, and quality of life in community-dwelling older adults.