Effect of respiratory muscle training on maximum aerobic power in normoxia and hypoxia

Article Article scientifique Article Effect of respiratory muscle training on maximum aerobic power in normoxia and hypoxia eng 2010 author Esposito Fabio 99266 author Limonta Eloisa author Alberti Giampiero author Veicsteinas Arsenio author Ferretti Guido 22968 268-272 10.1016/j.resp.2010.02.004 20156604 1569-9048 http://www.sciencedirect.com/science?_ob=MImg&_imagekey=B6X16-4YCS032-1-1&_cdi=7234&_user=779890&_pii=S1569904810000509&_orig=search&_coverDate=03%2F31%2F2010&_sk=998299996&view=c&wchp=dGLzVzz-zSkzk&md5=dd384e90e21a93fbde1ba64e3a466bd9&ie=/sdarticle.pdf To assess the effects of respiratory muscle training (RMT) on maximum oxygen uptake (VO2max) in normoxia and hypoxia, 9 healthy males (age 24 +/- 4 years; stature 1.75 +/- 0.08 m; body mass 72 +/- 9 kg; mean +/- SD) performed on different days maximal incremental tests on a cycle ergometer in normoxia and normobaric hypoxia (FIO2=0.11), before and after 8 weeks of RMT (5 days/week). During each test, gas exchange variables were measured breath-by-breath by a metabolimeter. After RMT, no changes in cardiorespiratory and metabolic variables were detected at maximal exercise in normoxia. On the contrary, in hypoxia expired and alveolar ventilation (V(E(and V(A), respectively) at maximal exercise were significantly higher than pre-training condition (+12 and +13%, respectively; P < 0.05). Accordingly, alveolar O2 partial pressure (PAO2) after RMT significantly increased by approximately 10%. Nevertheless, arterial PO2 and VO2max did not change with respect to pre-training condition. In conclusion, RMT improved respiratory function but did not have any effect on VO2max, neither under normoxic nor hypoxic condition. In hypoxia, the significant increase in V(E) and V(A) at maximum exercise after training lead to higher alveolar but not arterial PO2 values, revealing an increased A-a gradient. This result, according to the theoretical models of VO2max limitation, seems to contradict the lack of VO2max increase in hypoxia, suggesting a possible role of increased ventilation-perfusion mismatch. Dewey 616.8 53 Département de neurosciences fondamentales 21A false 376 Métabolisme énergétique 642 Respiratory physiology & neurobiology 170 3 67b75367-7e1a-48dc-81ae-7da4c190ed63 Article Restricted file1.pdf 217172 application/pdf restrictedAccess Faculté de médecine / Section de médecine fondamentale / Département de neurosciences fondamentales

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Effect of respiratory muscle training on maximum aerobic power in normoxia and hypoxia	Respiratory physiology & neurobiology			2010	710	0

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Esposito, Fabio