Inspiratory muscle training in addition to whole body vibration for functional and physical outcomes in pre-frail older women: a randomized controlled trial

Background: to investigate the efficacy of addition of inspiratory muscle training (IMT) to the whole body vibration (WBV) on functional outcomes, physical performance, muscle strength and metabolism in pre-frail older women.

Methods: this study was a randomized double-blind trial. Forty-two older women aged 60-80 years who meet the Cardiovascular Health Study frailty criteria for pre-frailty were randomly allocated to IMT + WBV, IMTsham + WBV or Sham groups. IMT + WBV group received 12 weeks of both trainings, whereas IMTsham + WVB received 12 weeks of WBV alone. Sham group received 12 weeks of IMT with a low fixed load and were positioned at the vibratory platform without therapeutic effect. Participants were evaluated before and after the intervention for the following outcomes: 6-min walk test distance (6MWD), balance using Tinetti test, functional mobility using timed up and go test (TUG), handgrip strength (HGS) and peripheral muscle metabolism (glucose and lactate levels).

Results: after the training, both groups IMT + WBV and IMTsham + WBV improved 6MWD [mean percentage changes = 20.31 (SD = 14.62) and 13.02 (SD = 12.14), respectively] compared with Sham [0.27 (SD = 6.51)], P <0.01. There was also a significant decrease of mean percentage changes on time of the TUG for IMT + WBV [-21.87 (SD = 7.87)] and IMTsham + WBV [-11.15 (SD = 13.64)] compared with Sham [-4.25 (SD = 13.25)], P <0.01. IMT + WBV group improved balance when compared with IMTsham + WBV and Sham groups (P <0.05 and < 0.01, respectively). HGS and levels of lactate and glucose were similar between groups.

Conclusions: the addition of IMT to the WBV was effective to improve functionality, balance and physical performance in pre-frail older women.