{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,22]],"date-time":"2026-07-22T10:59:46Z","timestamp":1784717986724,"version":"3.55.0"},"reference-count":39,"publisher":"Public Library of Science (PLoS)","issue":"5","license":[{"start":{"date-parts":[[2025,5,23]],"date-time":"2025-05-23T00:00:00Z","timestamp":1747958400000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"JSPS KAKENHI","award":["24K14301"],"award-info":[{"award-number":["24K14301"]}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"<jats:p>Aerobic exercise is more recommended than anaerobic exercise for individuals with cardiopulmonary dysfunction to avoid cardiopulmonary stress. However, their oxygen-carrying capacity is already reduced, making it difficult to exercise enough. Therefore, we aimed to investigate whether mild hyperbaric hyperoxia enhances aerobic capacity and decreases cardiopulmonary stress during exercise with a particular focus on the ventilatory threshold (VT). Nineteen healthy men (age 34.9\u2009\u00b1\u200910.8 years) performed ramp-loading tests on a cycle-ergometer under the three oxygen conditions: hypobaric hypoxia (HYPO; 0.7 ATA, 14.7% O<jats:sub>2<\/jats:sub>), normobaric normoxia (NOR; 1.0 ATA, 21% O<jats:sub>2<\/jats:sub>), and mild hyperbaric hyperoxia (HYPER; 1.3 ATA, 35% O<jats:sub>2<\/jats:sub>). Cardiopulmonary data were recorded using a gas exchange analyzer. VT was assessed based on minute ventilation (V<jats:sub>E<\/jats:sub>) using the V-slope method and the work rate on VT (W<jats:sub>VT<\/jats:sub>) was determined. Although the maximal values of V<jats:sub>E<\/jats:sub> did not differ among the oxygen conditions, W<jats:sub>VT<\/jats:sub> in the HYPER condition was significantly higher compared to others (HYPO; 125\u2009\u00b1\u200921, NOR; 148\u2009\u00b1\u200924, HYPER; 168\u2009\u00b1\u200932 [W], each p\u2009&lt;\u20090.01). Systolic blood pressure and double product on VT in the HYPER condition were significantly reduced compared to others (HYPO; 172\u2009\u00b1\u200921, 23096\u2009\u00b1\u20094354, NOR; 173\u2009\u00b1\u200915, 23377\u2009\u00b1\u20093109, HYPER; 155\u2009\u00b1\u200918, 21255\u2009\u00b1\u20093340 [mmHg, beats\u00b7min<jats:sup>-1<\/jats:sup>\u00b7mmHg], each p\u2009&lt;\u20090.05). Although further clinical research targeting other populations is needed to apply mild hyperbaric hyperoxia in clinical practice, due to its positive effects on W<jats:sub>VT<\/jats:sub> and cardiopulmonary stress, the HYPER oxygen condition may potentially be used to enhance aerobic capacity and make individuals with cardiopulmonary dysfunction exercise safely.<\/jats:p>","DOI":"10.1371\/journal.pone.0323885","type":"journal-article","created":{"date-parts":[[2025,5,23]],"date-time":"2025-05-23T17:40:47Z","timestamp":1748022047000},"page":"e0323885","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":2,"title":["Mild hyperbaric hyperoxia improves aerobic capacity and suppresses cardiopulmonary stress during the maximal cycle-ergometer 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