The effect of inspiratory muscle training on the quality of life, immune response, inspiratory and lower limb muscle strength of older adults: a randomized controlled trial

Abstract

Objective: To evaluate the impact of inspiratory muscle training (IMT) on the quality of life, immune response, inspiratory and lower limb muscle strength of older adults. Method: A randomized clinical trial was conducted with 30 institutionalized older adults. They were allocated into two groups: the IMT group (n=15), which underwent IMT with PowerBreathe Classic, using a load of 60% of maximal inspiratory pressure (MIP). This was performed using a 30 repetition protocol, three times a week, for six weeks. The second group was the control group (n=15) which did not perform any type of therapeutic intervention. In both groups, MIP, lower limb strength by sit-up test, quality of life by the SF-36 questionnaire and C-reactive protein (CRP) were evaluated. Results: The results demonstrated the homogeneity between the groups regarding the demographic and clinical variables. The IMT group showed an increase in the variation of MIP (9.20±7.36 cmH2O) compared to the control (0.93±8.79 cmH2O). Improvement was also observed in the sitting and standing test (p<0.05) (Tukey Test) in the difference between the values before and after the IMT. In terms of quality of life, two of the eight SF-36 domains were influenced by the IMT, namely: functional capacity and limitations due to physical factors. There were no changes in CRP in either group. Conclusion: IMT improved the inspiratory muscle strength, lower limb strength and quality of life of institutionalized older adults. These findings reinforce the contribution of this therapy to reducing the deleterious effects of aging.

Inspiratory Muscle Strength and Cardiorespiratory Fitness Association With Health-Related Quality of Life in Healthy Older Adults

“…The aging of both muscular systems is different, and although sarcopenia appears also in the respiratory muscles, it is a slower process compared with peripheral muscles (Shin et al, 2017 ) which are responsible for any physical activity and/or social relationships. Despite this, it is interesting to know that 6 weeks of inspiratory muscle training are able to improve HRQoL in relation to functionality domains (functional capacity and physical limitations) (Vilaça et al, 2019 ). Perhaps, this association depends not only on structural factors (a greater lower limb tone allows walking more, and therefore greater HRQoL) but also on nervous factors as a consequence of the metaboreflex (a greater inspiratory muscle tone results in walking more and a higher HRQoL).…”

“…This multifactorial predictor is severely affected by the aging process, which involves alterations and adaptations in all body systems (Vilaça et al, 2019 ), with special attention to the decline in muscle mass (Cruz-Jentoft et al, 2019 ) and muscle strength (Blasco-Lafarga et al, 2020 ). These two factors, muscle mass and muscle strength, follow similar, but not equal impairment processes (Blasco-Lafarga et al, 2021 ).…”

“…These authors suggested that lower values in FVC and FEV1 were associated with decreased scores in total HRQoL and physical domain in participants without comorbidities. According to recent studies, respiratory muscle weakness alone becomes a major limiting factor for physical fitness improvement, since it triggers a reduction in general muscle strength, dyspnea, and changes in lung function (Vilaça et al, 2019 ). This fact indicates that changes in inspiratory muscle strength (a variable little used in the field of healthy older adults), could detect respiratory diseases earlier than spirometric values (Schoser et al, 2017 ), being important to know the optimal maximum inspiratory force values for each age group, even in the absence of pathology.…”

Link between muscle function and physical function in critically ill patients

“…In comparison, our participants performed the 6-MWT at hospital discharge whereas in other research studies, critically ill survivors performed the 6-MWT at three, six-and twelve-months post-hospital discharge (86,103). When comparing our results to other research studies whereby participants performed the 6-MWT post-hospital discharge, our participants perfomed much worse in the 6-MWT at hospital discharge.The relationship between respiratory muscle strength and the 6-MWT has been extensively studied in the chronic obstructive pulmonary disease (COPD) population and healthy elderly population (104,105,106). To my knowledge, ours is the first study to describe a positive significant correlation between maximal inspiratory pressure (MIP) and the 6-MWT and a moderate positive correlation between the MRC-SS and the 6-MWT in critically ill survivors.…”