Inspiratory muscle training
The number of RCTs that studied the effect of inspiratory
muscle training (IMT) in patients with asthma is scarce.
Table 3 illustrates the Cochrane review and three included
studies since the Cochrane review. Two of the three trials
mainly examined changes in lung function. Subjective
outcome measures such as quality of life and asthma control
are not examined in these studies.
Two of the three trials10,14 examined whether the maximal
inspiratory pressure (PImax) changed through IMT. Both
studies found a significant increase in PImax after training,
compared to the control group14 or pre versus post training.10
Only one study14 examined whether IMT can reduce
symptoms, this study found a significant decrease in nocturnal
symptoms compared to the control group. Beside the
improvement of PImax, not many significant improvements
in lung function are found. One14 of the two studies which
examined PEF found a significant increase. Also only one
study14 has examined medication use, this study found
a significant reduction in bronchodilator use.
In conclusion, inspiratory muscle training can improve
maximal inspiratory pressure and might reduce medication
use, reduce symptoms and improve lung function, but the
number of studies is limited.