Abstract
Background: Reduced inspiratory muscle strength is characteristic of the healthy ageing process.
Methods: 24 healthy adults (mean age: 68.3±2.5 years) were evenly randomised into an inspiratory muscle training (IMT) or sham group. Participants in the IMT group performed 30 breaths, twice daily, for 8 weeks, at an initial intensity corresponding to ~50% maximal inspiratory pressure (PImax) and <15% PImax for the sham group. Pre- and 8-week measurements included PImax, six-minute walk distance (6MWD), and assessment of thoracoabdominal volumes via optoelectronic plethysmography during cycling at 75% of predicted peak work rate. Within group changes were assessed by paired t-tests.
Results: PImax significantly increased (by 20.0±11.9cmH2O; p=0.001) in the IMT group but did not change in the control group (by 2.4±9.3 cmH2O). 6MWD increased by 18.8±28.4m (p=0.042) in the IMT group with no change (-0.4±29.0m) in the control group. Post-IMT at a given level of minute ventilation during cycling, there was a significant (p=0.04) increase in the contribution of the pulmonary and abdominal rib cage compartments (reflecting intercostal and diaphragm muscle activity, respectively) to tidal volume (VT) expansion relative to that of the abdomen compartment (reflecting abdominal muscle activity). In contrast, in the sham group there was greater (p=0.001) contribution of the abdomen compartment to VT expansion relative to that of the pulmonary and abdominal rib cage compartments.
Conclusions: IMT is associated with increased 6MWD and PImax. Improved PImax translates into greater contribution of the rib cage muscles and the diaphragm to VT expansion during sub-maximal exercise.
Methods: 24 healthy adults (mean age: 68.3±2.5 years) were evenly randomised into an inspiratory muscle training (IMT) or sham group. Participants in the IMT group performed 30 breaths, twice daily, for 8 weeks, at an initial intensity corresponding to ~50% maximal inspiratory pressure (PImax) and <15% PImax for the sham group. Pre- and 8-week measurements included PImax, six-minute walk distance (6MWD), and assessment of thoracoabdominal volumes via optoelectronic plethysmography during cycling at 75% of predicted peak work rate. Within group changes were assessed by paired t-tests.
Results: PImax significantly increased (by 20.0±11.9cmH2O; p=0.001) in the IMT group but did not change in the control group (by 2.4±9.3 cmH2O). 6MWD increased by 18.8±28.4m (p=0.042) in the IMT group with no change (-0.4±29.0m) in the control group. Post-IMT at a given level of minute ventilation during cycling, there was a significant (p=0.04) increase in the contribution of the pulmonary and abdominal rib cage compartments (reflecting intercostal and diaphragm muscle activity, respectively) to tidal volume (VT) expansion relative to that of the abdomen compartment (reflecting abdominal muscle activity). In contrast, in the sham group there was greater (p=0.001) contribution of the abdomen compartment to VT expansion relative to that of the pulmonary and abdominal rib cage compartments.
Conclusions: IMT is associated with increased 6MWD and PImax. Improved PImax translates into greater contribution of the rib cage muscles and the diaphragm to VT expansion during sub-maximal exercise.
| Original language | English |
|---|---|
| Pages (from-to) | 2378-2378 |
| Number of pages | 1 |
| Journal | European Respiratory Journal |
| Volume | 60 |
| Issue number | suppl 66 |
| DOIs | |
| Publication status | Published - 4 Sept 2022 |
| Event | The European Respiratory Society (ERS) International Congress 2022 - Barcelona, Spain Duration: 4 Sept 2022 → 6 Sept 2022 |