, and control (n ؍ 25). The participants underwent anthropometric and cirtometric measurements associated with maximal respiratory pressures. We analyzed data using descriptive (mean and SD) and inferential statistics (1-way analysis of variance, Student t test, and Scheffé post hoc) with a level of significance of 5% (P < .05) and a CI of 95%. RESULTS: Although the anthropometric and cirtometric variables indicated similarity of values between groups (P > .05), the maximal inspiratory and expiratory pressures were considerably lower in the subjects with PD and AD (P < .01). CONCLUSIONS: The control of the anthropometric and cirtometric variables of the subjects indicates that RMS is affected by the aging process, and its decline increases in neurodegenerative conditions. This fact represents a serious risk for the development of atelectasis and other pneumo-functional complications, which must be considered in proposing of future therapies.