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Chacaltaya, Bolivia). This was done first with BV resulting from acclimatization (BV = 5.40 \u00b1 0.39 liters) and again 2\u20134 days later, 1 h after PV expansion with 1 liter of 6% dextran 70 (BV = 6.32 \u00b1 0.34 liters). PV expansion had no effect on Q\u0307<jats:sub>max<\/jats:sub>, maximal O<jats:sub>2<\/jats:sub> consumption (V\u0307o<jats:sub>2<\/jats:sub>), and exercise capacity. Despite maximal systemic O<jats:sub>2<\/jats:sub> transport being reduced 19% due to hemodilution after PV expansion, whole body V\u0307o<jats:sub>2<\/jats:sub> was maintained by greater systemic O<jats:sub>2<\/jats:sub> extraction ( P &lt; 0.05). Leg blood flow was elevated ( P &lt; 0.05) in hypervolemic conditions, which compensated for hemodilution resulting in similar leg O<jats:sub>2<\/jats:sub> delivery and leg V\u0307o<jats:sub>2<\/jats:sub> during exercise regardless of PV. Pulmonary ventilation, gas exchange, and acid-base balance were essentially unaffected by PV expansion. Sea level Q\u0307<jats:sub>max<\/jats:sub> and exercise capacity were restored with hyperoxia at altitude independently of BV. Low BV is not a primary cause for reduction of Q\u0307<jats:sub>max<\/jats:sub> at altitude when acclimatized. Furthermore, hemodilution caused by PV expansion at altitude is compensated for by increased systemic O<jats:sub>2<\/jats:sub> extraction with similar peak muscular O<jats:sub>2<\/jats:sub> delivery, such that maximal exercise capacity is unaffected. <\/jats:p>","DOI":"10.1152\/ajpheart.00840.2003","type":"journal-article","created":{"date-parts":[[2004,5,18]],"date-time":"2004-05-18T00:33:46Z","timestamp":1084840426000},"page":"H1214-H1224","source":"Crossref","is-referenced-by-count":51,"title":["Plasma volume expansion does not increase maximal cardiac output or VO<sub>2 max<\/sub> in lowlanders acclimatized to altitude"],"prefix":"10.1152","volume":"287","author":[{"given":"Jos\u00e9 A. 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