Effects of Inspiratory Muscle Training and Yoga Breathing Exercises on Respiratory Muscle Function in Institutionalized Frail Older Adults: A Randomized Controlled Trial
In the older adults, the respiratory function may be seriously compromised when a marked decrease of respiratory muscle (RM) strength coexists with comorbidity and activity limitation. Respiratory muscle training has been widely studied and recommended as a treatment option for people who are unable to participate in whole-body exercise training (WBET); however, the effects of inspiratory muscle training and yoga breathing exercises on RM function remain unknown, specifically in impaired older adults. To evaluate the effects of inspiratory threshold training (ITT) and yoga respiratory training (YRT) on RM function in institutionalized frail older adults. Eighty-one residents (90% women; mean age, 85 years), who were unable to perform WBET (inability to independently walk more than 10 m), were randomly assigned to a control group or one of the 2 experimental groups (ITT or YRT). Experimental groups performed a supervised interval-based training protocol, either through threshold inspiratory muscle training device or yoga breathing exercises, which lasted 6 weeks (5 days per week). Outcome measures were collected at 4 time points (pretraining, intermediate, posttraining, and follow-up) and included the maximum respiratory pressures (maximum inspiratory pressure [MIP] and maximum expiratory pressure [MEP]) and the maximum voluntary ventilation (MVV). Seventy-one residents completed the study: control (n = 24); ITT (n = 23); YRT (n = 24). The treatment on had a significant effect on MIP YRT (F6,204 = 6.755, P < .001, η = 0.166), MEP (F6,204 = 4.257, P < .001, η = 0.111), and MVV (F6,204 = 5.322, P < .001, η = 0.135). Analyses showed that the YRT group had a greater increase of RM strength (MIP and MEP) and endurance (MVV) than control and/or ITT groups. Yoga respiratory training appears as an effective and well-tolerated exercise regimen in frail older adults and may therefore be a useful alternative to ITT or no training, to improve RM function in older population, when WBET is not possible.