Effects of Added Resistance to Breathing in Obstructed Lung Disease.
Petsonk L; Boyles C; Hodous T; Hankinson J
NIOSH 1981 Dec:24 pages
Responses to exercise with and without added resistance to breathing of subjects with obstructive lung disease were compared to responses in normal population. Following the establishment of baseline spirometry, thoracic gas volume and airway resistance experiments were performed. Trials of treadmill exercise under varying airway resistance conditions were performed. Resistance to breathing conditions was designed to simulate the wearing of widely used respiratory protective masks. Normal subjects with forced expiratory volumes to forced ventilatory capacity ratios greater than or equal to 70 percent were compared to obstructed individuals with ratios less than 70 percent. For both normal and obstructed groups, exercise results were similar with and without added resistance; however, only the obstructed group showed a decline in ventilation as well as an increase in end tidal carbon-dioxide (124389) values. Obstructed subjects tended to ventilate less as well. None of these results reached statistical significance. The authors conclude that the trends shown in the obstructed subjects are the same as those shown in other studies of normal persons with greater added resistance and workload. There is no evidence that respiratory protective masks compromise physiologic functioning to a significant extent at low workloads or during short exercise periods.
Physiological-response; Respiratory-protective-equipment; Lung-disorders; Disease-incidence; Breathing-atmospheres; Ventilation; Physiological-testing; Breathing-zone; Respiratory-rate;
NTIS Accession No.
Clinical Investigations Branch, NIOSH, Morgantown, West Virginia, NTIS PB83-232-157, 24 pages, 10 references