Long-Term Effects of Inspiratory Muscle Training in Institutionalized Elderly Women: A Double-Blind Randomized Controlled Trial

Abstract

Background: Inspiratory muscle training (IMT) has been applied to different populations, but evidence in elderly women and maintenance of improvements achieved during training is scarce. The objective of the study was to evaluate the effectiveness of IMT 6 months after finishing the training period in elderly women. Methods: A controlled, randomized, double-blind trial was conducted, with allocation concealment performed on 26 institutionalized elderly women distributed into 2 groups: high loads and low loads. Over an 8-week period, an IMT protocol was followed; later, elderly women continued for 6 months with their daily normal activities. Inspiratory strength, expiratory strength, and functional capacity were measured pre-IMT, post-IMT, and 6 months after intervention. Results: After an 8-week training, respiratory strength and functional capacity increased in both groups. Six months after finishing the intervention, these benefits were lost. Inspiratory strength decreased in the high-loads group but was 32% higher than initial values (p = 0.007); in the low-loads group, patients lost 41% (p = 0.015). Improvements were higher in the high-loads group after training (p = 0.000) and follow-up (p = 0.002). Functional capacity was similar to initial values in both groups. Conclusion: The improvements achieved with IMT in elderly women disappeared 6 months after the end of training. High loads were more effective to keep inspiratory strength than low loads.