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Yokoi Y, Yanagihashi R, Morishita K, Goto N, Fujiwara T, Abe K. Recovery effects of repeated exposures to normobaric hyperoxia on local muscle fatigue. J Strength Cond Res 2015; 28:2173-9. [PMID: 24476781 DOI: 10.1519/jsc.0000000000000386] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Reported recovery effects of hyeroxia are conflicted. This study aimed to identify the effects and the mechanisms of normobaric hyperoxia on the recovery of local muscle fatigue, which is the most commonly encountered form of fatigue both daily and in training and competitions. Twelve male subjects performed 3 × 3 × no less than 30 seconds of isometric quadriceps exercise at 70% of maximum voluntary isometric contraction (MVIC) separated by two 15-minute recovery sessions under 1 of 2 different atmospheric oxygen concentrations, one in normoxia (NOX; 20.9% O2) and another in hyperoxia (HOX; 30.0% O2). To assess the degree of fatigue and recovery, 4 parameters were used; MVIC, endurance time to exhaustion, blood lactate, and perceived exertion measured by a visual analog scale (VAS). Maximum voluntary isometric contraction improved an average by approximately 14% in HOX compared with NOX at the conclusion of the second recovery session. However, this was not associated with changes in other parameters because changes in endurance time, blood lactate, and VAS during the trials were similar. Based on our findings, we conclude that 2 sets of 15-minute recovery session in normobaric hyperoxia are effective for restoring MVIC from local muscle fatigue induced by intermittent intense exercises. For quicker recovery, athletes are recommended to repeat 15-minute recovery process under 30.0% hyperoxia.
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Affiliation(s)
- Yuka Yokoi
- 1Koriyama Institute of Health Sciences, Fukushima, Japan; and 2Interdisciplinary Graduate School of Science and Technology, Shinshu University, Nagano, Japan
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Orbegozo Cortés D, Puflea F, Donadello K, Taccone FS, Gottin L, Creteur J, Vincent JL, De Backer D. Normobaric hyperoxia alters the microcirculation in healthy volunteers. Microvasc Res 2014; 98:23-8. [PMID: 25433297 DOI: 10.1016/j.mvr.2014.11.006] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Revised: 10/27/2014] [Accepted: 11/18/2014] [Indexed: 10/24/2022]
Abstract
The use of high concentrations of inhaled oxygen has been associated with adverse effects but recent data suggest a potential therapeutic role of normobaric hyperoxia (NH) in sepsis and cerebral ischemia. Hyperoxia may induce vasoconstriction and alter endothelial function, so we evaluated its effects on the microcirculation in 40 healthy adult volunteers using side-stream dark field (SDF) video-microscopy on the sublingual area and near-infrared spectroscopy (NIRS) on the thenar eminence. In a first group of volunteers (n=18), measurements were taken every 30 min: at baseline in air, during NH (close to 100% oxygen via a non-rebreathing mask) and during recovery in air. In a second group (n=22), NIRS measurements were taken in NH or ambient air on two separate days to prevent any potential influence of repeated NIRS measurements. NH significantly decreased the proportion of perfused vessels (PPV) from 92% to 66%, perfused vessel density (PVD) from 11.0 to 7.3 vessels/mm, perfused small vessel density (PSVD) from 9.0 to 5.8 vessels/mm and microvascular flow index (MFI) from 2.8 to 2.0, and increased PPV heterogeneity from 7.5% to 30.4%. Thirty minutes after return to air, PPV, PVD, PSVD and MFI remained partially altered. During NH, NIRS descending slope and NIRS muscle oxygen consumption (VO2) decreased from 8.5 to 7.9%/s and 127 to 103 units, respectively, in the first group and from 10.7 to 9.4%/s and 150 to 115 units in the second group. NH, therefore, alters the microcirculation in healthy subjects, decreasing capillary perfusion and VO2 and increasing the heterogeneity of the perfusion.
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Affiliation(s)
- Diego Orbegozo Cortés
- Department of Intensive Care, Erasme University Hospital, Université Libre de Bruxelles, Brussels, Belgium
| | - Florin Puflea
- Department of Intensive Care, Erasme University Hospital, Université Libre de Bruxelles, Brussels, Belgium; Intensive Care Department, Azienda Ospedaliera Universitaria Integrata (AOUI), Università degli Studi di Verona, Verona, Italy
| | - Katia Donadello
- Department of Intensive Care, Erasme University Hospital, Université Libre de Bruxelles, Brussels, Belgium
| | - Fabio Silvio Taccone
- Department of Intensive Care, Erasme University Hospital, Université Libre de Bruxelles, Brussels, Belgium
| | - Leonardo Gottin
- Intensive Care Department, Azienda Ospedaliera Universitaria Integrata (AOUI), Università degli Studi di Verona, Verona, Italy
| | - Jacques Creteur
- Department of Intensive Care, Erasme University Hospital, Université Libre de Bruxelles, Brussels, Belgium
| | - Jean-Louis Vincent
- Department of Intensive Care, Erasme University Hospital, Université Libre de Bruxelles, Brussels, Belgium
| | - Daniel De Backer
- Department of Intensive Care, Erasme University Hospital, Université Libre de Bruxelles, Brussels, Belgium.
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