Inclusion Criteria:  Healthy volunteers from Touro College of Osteopathic Medicine (TouroCOM), including students and staff, were recruited as subjects of this study. Any participant with recent or past medical history of obstructive or restrictive lung disorders, recent trauma, or illnesses, and/or chest abnormalities were excluded from the study.  Exclusion Criteria:  Certain study results were excluded on the basis of abnormal baseline measurements, including but not limited to, heart rate, oxygen saturation, respiratory rate, improper spirometer use, technique and/or high variance among the repeated measurements obtained for each participant.