Effects of Expiratory Muscle Training and Air Stacking on Peak Cough Flow in Individuals with Parkinson's Disease.

The purpose of this study was to investigate the effects of air stacking (AS) and an expiratory muscle training (EMT) program to increase voluntary and reflex peak cough flow (PCF) in individuals with Parkinson's disease. Participants were allocated to the control (n = 11), EMT (n = 11), or EMT + AS group (n = 11). All groups performed EMT (5 sets of 5 repetitions), 6 times a week for 2 months. The control group used a fixed resistance, EMT plus AS and EMT groups used a progressively increased resistance. The EMT plus AS group additionally performed 10 series of three to four lung insufflations using a manual resuscitator bag. Voluntary and reflex PCF, maximum expiratory pressure, and slow vital capacity were assessed before and after training. EMT plus AS was more beneficial than EMT alone for improving reflex and voluntary PCF. The effect of the EMT plus AS was greater for reflex PCF than for voluntary PCF.