{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,1]],"date-time":"2026-04-01T11:27:50Z","timestamp":1775042870473,"version":"3.50.1"},"reference-count":41,"publisher":"Oxford University Press (OUP)","issue":"8","license":[{"start":{"date-parts":[[2006,4,1]],"date-time":"2006-04-01T00:00:00Z","timestamp":1143849600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/pages\/standard-publication-reuse-rights"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2006,4,15]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Rationale<\/jats:title>\n                    <jats:p>Breathing supplemental oxygen reduces breathlessness during exercise in patients with chronic obstructive pulmonary disease (COPD). Replacing nitrogen with helium reduces expiratory flow resistance and may improve lung emptying. Combining these treatments should be independently effective.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Objectives<\/jats:title>\n                    <jats:p>Study the effect of changing oxygen or helium concentration in inspired gas during exercise in patients with stable COPD.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>In 82 patients (mean age, 69.7 yr; mean FEV1, 42.6% predicted), we measured endurance shuttle walking distance, resting and exercise oxygen saturation, and end-exercise dyspnea (Borg scale) while patients breathed Heliox28 (72% He\/28% O2), Heliox21 (79% He\/21% O2), Oxygen28 (72% N2\/28% O2), or medical air (79% N2\/21% O2). Gases were administered using a randomized, blinded, crossover design via a face mask and an inspiratory demand valve.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Breathing Heliox28 increased walking distance (mean \u00b1 SD, 147 \u00b1 150 m) and reduced Borg score (\u22121.28 \u00b1 1.30) more than any other gas mixture. Heliox21 significantly increased walking distance (99 \u00b1 101 m) and reduced dyspnea (Borg score, \u22120.76 \u00b1 0.77) compared with medical air. These changes were similar to those breathing Oxygen28. The effects of helium and oxygen in Heliox28 were independent. The increase in walking distance while breathing Heliox28 was inversely related to baseline FEV1 breathing air.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Reducing inspired gas density can improve exercise performance in COPD as much as increasing inspired oxygen. These effects can be combined as Heliox28 and are most evident in patients with more severe airflow obstruction.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1164\/rccm.200506-925oc","type":"journal-article","created":{"date-parts":[[2006,1,26]],"date-time":"2006-01-26T21:04:02Z","timestamp":1138309442000},"page":"865-870","source":"Crossref","is-referenced-by-count":81,"title":["The Effect of Helium and Oxygen on Exercise Performance in Chronic Obstructive Pulmonary Disease"],"prefix":"10.1093","volume":"173","author":[{"given":"Elizabeth A.","family":"Laude","sequence":"first","affiliation":[{"name":"Respiratory Medicine, Royal Hallamshire Hospital; Department of General Practice and Primary Care, ScHARR; Biomedical Science, University of Sheffield, Sheffield; Clinical Sciences, University Hospital Aintree, Liverpool; St. George's, University of London, London; and BOC Ltd., Guildford, United Kingdom"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nicholas C.","family":"Duffy","sequence":"additional","affiliation":[{"name":"Respiratory Medicine, Royal Hallamshire Hospital; Department of General Practice and Primary Care, ScHARR; Biomedical Science, University of Sheffield, Sheffield; Clinical Sciences, University Hospital Aintree, Liverpool; St. George's, University of London, London; and BOC Ltd., Guildford, United Kingdom"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chloe","family":"Baveystock","sequence":"additional","affiliation":[{"name":"Respiratory Medicine, Royal Hallamshire Hospital; Department of General Practice and Primary Care, ScHARR; Biomedical Science, University of Sheffield, Sheffield; Clinical Sciences, University Hospital Aintree, Liverpool; St. George's, University of London, London; and BOC Ltd., Guildford, United Kingdom"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Beatriz","family":"Dougill","sequence":"additional","affiliation":[{"name":"Respiratory Medicine, Royal Hallamshire Hospital; Department of General Practice and Primary Care, ScHARR; Biomedical Science, University of Sheffield, Sheffield; Clinical Sciences, University Hospital Aintree, Liverpool; St. George's, University of London, London; and BOC Ltd., Guildford, United Kingdom"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Michael J.","family":"Campbell","sequence":"additional","affiliation":[{"name":"Respiratory Medicine, Royal Hallamshire Hospital; Department of General Practice and Primary Care, ScHARR; Biomedical Science, University of Sheffield, Sheffield; Clinical Sciences, University Hospital Aintree, Liverpool; St. George's, University of London, London; and BOC Ltd., Guildford, United Kingdom"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rod","family":"Lawson","sequence":"additional","affiliation":[{"name":"Respiratory Medicine, Royal Hallamshire Hospital; Department of General Practice and Primary Care, ScHARR; Biomedical Science, 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