This study investigated the effects of a non-contact boxing exercise program on maximum expiratory pressure and aerodynamic voice measurements.
Methods: Eight adult males diagnosed with Parkinson's disease participated in the study. Individuals participated in twice-weekly exercise classes lasting one hour across 12-months. Dependent variables were measured on three baseline days and then at six additional time points. A pressure meter acquired maximum expiratory pressure, and a pneumotachograph system acquired transglottal airflow and subglottal air pressure.
Results: Measures of average maximum expiratory pressure significantly increased after 9- and 12- months of exercise when compared to baseline. There was an increasing trend for these measures in all participants, with a corresponding large effect size. Measures of transglottal airflow and subglottal pressure did not change over the course of 9- or 12-months, although their stability may indicate that the exercise program influenced maintenance of respiratory-phonatory coordination during voicing.
Conclusions: A non-contact boxing exercise program had a significant effect on maximum expiratory pressure in people with Parkinson's disease. The aerobic nature of the program and challenges to the respiratory muscles potentially explain the "ingredient" causing this effect. The small sample size of this pilot study necessitates future research incorporating larger and more diverse participants.
Keywords: Parkinson’s disease; dysphonia; respiration.