{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,17]],"date-time":"2026-09-17T06:29:58Z","timestamp":1789626598080,"version":"build-2803163510"},"reference-count":26,"publisher":"American Physiological Society","issue":"6","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Journal of Applied Physiology"],"published-print":{"date-parts":[[1999,12,1]]},"abstract":"<jats:p> We sought to determine whether apnea-induced cardiovascular responses resulted in a biologically significant temporary O<jats:sub>2<\/jats:sub> conservation during exercise. Nine healthy men performing steady-state leg exercise carried out repeated apnea (A) and rebreathing (R) maneuvers starting with residual volume +3.5 liters of air. Heart rate (HR), mean arterial pressure (MAP), and arterial O<jats:sub>2<\/jats:sub> saturation (Sa<jats:sub>O<jats:sub>2<\/jats:sub> <\/jats:sub>; pulse oximetry) were recorded continuously. Responses (\u0394HR, \u0394MAP) were determined as differences between HR and MAP at baseline before the maneuver and the average of values recorded between 25 and 30 s into each maneuver. The rate of O<jats:sub>2<\/jats:sub> desaturation (\u0394Sa<jats:sub>O<jats:sub>2<\/jats:sub> <\/jats:sub>\/\u0394 t) was determined during the same time interval. During apnea, \u0394SaO<jats:sub>2<\/jats:sub>\/\u0394 t had a significant negative correlation to the amplitudes of \u0394HR and \u0394MAP ( r <jats:sup>2<\/jats:sup>\u2009=\u20090.88, P\u2009&lt;\u20090.001); i.e., individuals with the most prominent cardiovascular responses had the slowest \u0394Sa<jats:sub>O<jats:sub>2<\/jats:sub> <\/jats:sub>\/\u0394 t. \u0394HR and \u0394MAP were much larger during A (\u221244\u2009\u00b1\u20098 beats\/min, +49 \u00b1 4 mmHg, respectively) than during R maneuver (+3\u2009\u00b1\u20093 beats\/min, +30\u2009\u00b1\u20095 mmHg, respectively). \u0394Sa<jats:sub>O<jats:sub>2<\/jats:sub> <\/jats:sub>\/\u0394 t during A and R maneuvers was \u22121.1\u2009\u00b1\u20090.1 and \u22122.2\u2009\u00b1\u20090.2% units\/s, respectively, and nadir Sa<jats:sub>O<jats:sub>2<\/jats:sub> <\/jats:sub> values were 58 \u00b1 4 and 42 \u00b1 3% units, respectively. We conclude that bradycardia and hypertension during apnea are associated with a significant temporary O<jats:sub>2<\/jats:sub> conservation and that respiratory arrest, rather than the associated hypoxia, is essential for these responses. <\/jats:p>","DOI":"10.1152\/jappl.1999.87.6.2122","type":"journal-article","created":{"date-parts":[[2017,12,22]],"date-time":"2017-12-22T16:43:05Z","timestamp":1513960985000},"page":"2122-2127","source":"Crossref","is-referenced-by-count":67,"title":["Oxygen-conserving effects of apnea in exercising men"],"prefix":"10.1152","volume":"87","author":[{"given":"Peter","family":"Lindholm","sequence":"first","affiliation":[{"name":"Section of Environmental Physiology, Department of Physiology and Pharmacology, Karolinska Institutet, SE-171 77 Stockholm, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Patrik","family":"Sundblad","sequence":"additional","affiliation":[{"name":"Section of Environmental Physiology, Department of Physiology and Pharmacology, Karolinska Institutet, SE-171 77 Stockholm, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dag","family":"Linnarsson","sequence":"additional","affiliation":[{"name":"Section of Environmental Physiology, Department of Physiology and Pharmacology, Karolinska Institutet, SE-171 77 Stockholm, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"24","reference":[{"key":"B1","first-page":"21","volume":"25","author":"Andersson J.","year":"1998","journal-title":"Undersea Hyper. Med."},{"key":"B2","doi-asserted-by":"publisher","DOI":"10.1007\/s004210050245"},{"key":"B3","doi-asserted-by":"publisher","DOI":"10.1111\/j.1748-1716.1984.tb07427.x"},{"key":"B4","doi-asserted-by":"publisher","DOI":"10.1152\/physrev.1997.77.3.837"},{"key":"B5","doi-asserted-by":"publisher","DOI":"10.1016\/0034-5687(87)90091-0"},{"key":"B6","doi-asserted-by":"publisher","DOI":"10.1152\/jappl.1968.24.6.773"},{"key":"B7","doi-asserted-by":"publisher","DOI":"10.1016\/S0140-6736(79)91218-2"},{"key":"B10","doi-asserted-by":"publisher","DOI":"10.1038\/icb.1971.47"},{"key":"B11","doi-asserted-by":"publisher","DOI":"10.1152\/jappl.1991.70.2.794"},{"key":"B12","doi-asserted-by":"publisher","DOI":"10.1152\/jappl.1997.83.4.1282"},{"key":"B13","doi-asserted-by":"publisher","DOI":"10.1152\/jappl.1976.41.3.336"},{"key":"B14","doi-asserted-by":"publisher","DOI":"10.1152\/jappl.1968.25.5.542"},{"key":"B15","doi-asserted-by":"publisher","DOI":"10.1152\/jappl.1972.33.4.502"},{"key":"B16","doi-asserted-by":"publisher","DOI":"10.1152\/jappl.1971.30.4.540"},{"key":"B17","doi-asserted-by":"publisher","DOI":"10.1097\/00004872-198900076-00025"},{"key":"B18","first-page":"332","volume":"9","author":"Kurenkov H. I.","year":"1973","journal-title":"F\u00f6rsvarsmedicin (Swed. J. Defence Med.)"},{"key":"B19","doi-asserted-by":"publisher","DOI":"10.1249\/00003677-198201000-00009"},{"key":"B21","doi-asserted-by":"publisher","DOI":"10.1152\/jappl.1983.54.1.166"},{"key":"B22","doi-asserted-by":"publisher","DOI":"10.1152\/jappl.1983.54.1.172"},{"key":"B23","doi-asserted-by":"publisher","DOI":"10.2165\/00007256-199009050-00004"},{"key":"B26","first-page":"13","volume":"25","author":"Schagatay E.","year":"1998","journal-title":"Undersea Hyper. Med."},{"key":"B27","doi-asserted-by":"publisher","DOI":"10.1152\/jappl.1962.17.2.184"},{"key":"B29","doi-asserted-by":"publisher","DOI":"10.1152\/jappl.1970.28.5.614"},{"issue":"40","key":"B30","first-page":"H1370","volume":"271","author":"Sundblad P.","year":"1996","journal-title":"Am. J. Physiol."},{"key":"B31","doi-asserted-by":"publisher","DOI":"10.1152\/jappl.1994.76.1.445"},{"key":"B32","first-page":"242","volume":"78","author":"Wolf S.","year":"1965","journal-title":"Trans. Assoc. Am. Physicians"}],"container-title":["Journal of Applied Physiology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.physiology.org\/doi\/pdf\/10.1152\/jappl.1999.87.6.2122","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2019,9,8]],"date-time":"2019-09-08T18:36:29Z","timestamp":1567967789000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.physiology.org\/doi\/10.1152\/jappl.1999.87.6.2122"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1999,12,1]]},"references-count":26,"journal-issue":{"issue":"6","published-print":{"date-parts":[[1999,12,1]]}},"alternative-id":["10.1152\/jappl.1999.87.6.2122"],"URL":"https:\/\/doi.org\/10.1152\/jappl.1999.87.6.2122","relation":{},"ISSN":["8750-7587","1522-1601"],"issn-type":[{"value":"8750-7587","type":"print"},{"value":"1522-1601","type":"electronic"}],"subject":[],"published":{"date-parts":[[1999,12,1]]}}}