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The Effects of Breathing Resistance on Pulmonary Function and Work Capacity

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The Effects of Breathing Resistance on Pulmonary Function and Work Capacity University of Montana ScholarWorks at University of Montana Graduate Student Theses, Dissertations, & Professional Papers Graduate School 1991 The effects of breathing resistance on pulmonary function and work capacity Zachary Mead The University of Montana Follow this and additional works at: https://scholarworks.umt.edu/etd Let us know how access to this document benefits ou.y Recommended Citation Mead, Zachary, "The effects of breathing resistance on pulmonary function and work capacity" (1991). Graduate Student Theses, Dissertations, & Professional Papers. 7215. https://scholarworks.umt.edu/etd/7215 This Thesis is brought to you for free and open access by the Graduate School at ScholarWorks at University of Montana. It has been accepted for inclusion in Graduate Student Theses, Dissertations, & Professional Papers by an authorized administrator of ScholarWorks at University of Montana. For more information, please contact [email protected]. Maureen and Mike MANSFIELD LIBRARY Copying allowed as provided under provisions of the Fair Use Section of the U.S. COPYRIGHT LAW, 1976. Any copying for commercial purposes or fiiiancM gain may be under^en only with the author’s written consent. University of Montana Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. THE EFFECTS OF BREATHING RESISTANCE ON PULMONARY FUNCTION AND WORK CAPACITY by Zachary Mead B.S. California State University, Bakersfield, 1987 Presented in partial fulfillm ent of the requirements for the degree of Master of Science University of Montana 1991 Approved b Chairman, Board of Examiners Dean, Graduate School 4 , Date Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. UMI Number: EP38016 All rights reserved INFORMATION TO ALL USERS The quality of this reproduction is dependent upon the quality of the copy submitted. In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted. Also, if material had to be removed, a note will indicate the deletion. UMT DiasorWion Punishing UMI EP38016 Published by ProQuest LLC (2013). Copyright in the Dissertation held by the Author. Microform Edition © ProQuest LLC. All rights reserved. This work is protected against unauthorized copying under Title 17, United States Code uesf ProQuest LLC. 789 East Eisenhower Parkway P.O. Box 1346 Ann Arbor, Ml 48106-1346 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. ABSTRACT Mead, Zachary P.. M.S. March 1991 Exercise Physiology The Effects of Breathing Resistance on_Pu1nmary F unction and Work Capacity ( 47pp. ) Director: Dr. Brian J. Sharkey^ The purpose of this study was to examine the relationship of several pulmonary function variables and the ventilatory threshold (VT) to work performance ( V02 max aid submax) while wearing an air purifying respirator. It was anticipated that one of the pulmonary function variables might be identified as a possible screening test to Identify workers capable of doing strenuous work < 1.5 Liters 02/minute) while wearing an air purifying respirator. Fifteen male subjects underwent pulmonary function testing, force vital capacity (FVC), forced expiratory volume in one second (FEYi.o), Forced expiratory flow 25-75 (FEF25-75), and the maximal voluntary ventilation in 15 seconds ( MVViS) both with and without the respirator mask. Subjects also performed two maximal treadmill tests at a walking speed of 4 mph with grade increases of 2.5S every 1 to 2 minutes. One treadmill test was performed with an a ir purifying respirator mask and one was performed without the mask. The results of this study show that working with an a ir purifying respirator device significantly (p i 0.05) reduces ventilation, V02 max, MVVis and the ventilatory threshold (VT), as compared to the no respirator condition. When the pulmonary function values were correlated ( r = 0.36) with work performance (V02 max) the MVVis pulmonary function test emerged as a possible test. The MVVis is also a negative correlate ( r = -0.44) of the ventilation requirement to perform submaximal work (2 2 -2 5 ml 02/kg/min). The results of this study show that the MVVis in combination with other variables such as fitness (V02 max) and the ventilatory threshold (VT) could become a screening test for workers that may be assigned to strenuous work tasks which require them to wear air purifying respirator devices. II Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. ACKNOWLEDGMENTS I would like to thank Dr. Brian Sharkey for Involving me with this project and other endeavors related to the U. S. Forest Service. The rest of the members of my thesis committee also deserve thanks for the suggestions they made regarding this manuscript. A big thanks goes to the young men that served as subjects In this study. The testing was sometimes less than pleasant yet the subjects always seemed interested and were always willing to give their all. 1 would especially like to thank my dear friend Greg Farnum for all the help with the data collection and the recruitment of subjects. A very big thanks goes to my best friend Zoe Alderfer. She provided me with endless support and the required amount of prodding to get me through this project. ill Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. TABLE OF CONTENTS ABSTRACT..........................................................................................................11 ACKNOWLEDGMENTS.........................................................................................Ill LIST OF TABLES......................................................................... Vl LIST OF FIGURES........................................................................................... v11 CHAPTER PAGE. I. INTRODUCTION................................................................................... 1 Significance Of Problem ................................................................2 Delimitations .............................................................................. 3 Limitations .................................................................................. 3 Hypotheses .................................................................................. 4 Definitions .................................................................................. 5 II. LITERATURE REVIEW............................................................................ 6 HI. METHODOLOGY ...................................................................................... 12 Phase One .................................................................................. 12 Phase Two .................................................................................. 13 Phase T h re e ..................................................................................... 15 IV. RESULTS AND DISCUSSION.......................................................................16 R e s u lts ............................................................................................. 16 Discussion .........................................................................................26 V. SUMMARY, CONCLUSIONS, AND RECOMMENDATIONS...............................34 Summary .........................................................................................34 Conclusions .........................................................................................36 Recommendations ............................................................................. 38 REFERENCES.........................................................................................................39 iv Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. APPENDIX £AÜE A. MEDICAL HISTORY QUESTIONNAIRE...........................................................43 B. INFORMED CONSENT................................................................................. 46 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. LIST OF TABLES TABLE £AQE 1 Descriptive Characteristics Of the S u b je cts ............................. 18 2 Group Means for Several Pulmonary Function T e s t s ................. 19 3 Mask/No Mask Differences For the Pulmonary Function Variables 20 4 Significant Differences Among Selected Variables .................... 21 5 Correlations Among Selected V aria bles ..................................... 22 6 Dyspnea Scale (RPE Scale) ........................................................... 23 VI Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. LIST OF FIGURES FIGURE PML 1 Subject Performing a Pulmonary Function T e s t .........................24 2 Subject Undergoing a Treadmill Work T e s t ................................25 vii Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. CHAPTER I INTRODUCTION Many occupational settings expose workers to harmful atmospheres. Respiratory protective devices of many types are used to shield the worker. These respiratory protective devices fall within three categories: 1 . air purifying devices; 2. supplted-air respirators; and 3. self contained breathing
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