Max E Weston, Neil Armstrong, Bert Bond, Owen W Tomlinson, Craig A Williams, Alan R Barker
{"title":"急性缺氧对青春期前男孩自行车运动中摄氧率和肌肉氧合动力学的影响","authors":"Max E Weston, Neil Armstrong, Bert Bond, Owen W Tomlinson, Craig A Williams, Alan R Barker","doi":"10.1123/pes.2023-0089","DOIUrl":null,"url":null,"abstract":"<p><strong>Purpose: </strong>To examine the effect of normobaric hypoxia on pulmonary oxygen uptake (V˙O2) and muscle oxygenation kinetics during incremental and moderate-intensity exercise in children.</p><p><strong>Methods: </strong>Eight prepubertal boys (9-11 y) performed incremental cycle tests to exhaustion in both normoxia and hypoxia (fraction of inspired O2 of 15%) followed by repeat 6-minute transitions of moderate-intensity exercise in each condition over subsequent visits.</p><p><strong>Results: </strong>Maximal oxygen uptake (V˙O2max) was reduced in hypoxia compared with normoxia (1.69 [0.20] vs 1.87 [0.26] L·min-1, P = .028), although the gas exchange threshold was not altered in absolute terms (P = .33) or relative to V˙O2max (P = .78). During moderate-intensity exercise, the phase II V˙O2 time constant (τ) was increased in hypoxia (18 [9] vs 24 [8] s, P = .025), with deoxyhemoglobin τ unchanged (17 [8] vs 16 [6], P ≥ .28).</p><p><strong>Conclusions: </strong>In prepubertal boys, hypoxia reduced V˙O2max and slowed V˙O2 phase II kinetics during moderate-intensity exercise, despite unchanged deoxyhemoglobin kinetics. These data suggest an oxygen delivery dependence of V˙O2max and moderate-intensity V˙O2 kinetics under conditions of reduced oxygen availability in prepubertal boys.</p>","PeriodicalId":49712,"journal":{"name":"Pediatric Exercise Science","volume":" ","pages":"1-8"},"PeriodicalIF":1.4000,"publicationDate":"2024-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"The Influence of Acute Hypoxia on Oxygen Uptake and Muscle Oxygenation Kinetics During Cycling Exercise in Prepubertal Boys.\",\"authors\":\"Max E Weston, Neil Armstrong, Bert Bond, Owen W Tomlinson, Craig A Williams, Alan R Barker\",\"doi\":\"10.1123/pes.2023-0089\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p><strong>Purpose: </strong>To examine the effect of normobaric hypoxia on pulmonary oxygen uptake (V˙O2) and muscle oxygenation kinetics during incremental and moderate-intensity exercise in children.</p><p><strong>Methods: </strong>Eight prepubertal boys (9-11 y) performed incremental cycle tests to exhaustion in both normoxia and hypoxia (fraction of inspired O2 of 15%) followed by repeat 6-minute transitions of moderate-intensity exercise in each condition over subsequent visits.</p><p><strong>Results: </strong>Maximal oxygen uptake (V˙O2max) was reduced in hypoxia compared with normoxia (1.69 [0.20] vs 1.87 [0.26] L·min-1, P = .028), although the gas exchange threshold was not altered in absolute terms (P = .33) or relative to V˙O2max (P = .78). During moderate-intensity exercise, the phase II V˙O2 time constant (τ) was increased in hypoxia (18 [9] vs 24 [8] s, P = .025), with deoxyhemoglobin τ unchanged (17 [8] vs 16 [6], P ≥ .28).</p><p><strong>Conclusions: </strong>In prepubertal boys, hypoxia reduced V˙O2max and slowed V˙O2 phase II kinetics during moderate-intensity exercise, despite unchanged deoxyhemoglobin kinetics. These data suggest an oxygen delivery dependence of V˙O2max and moderate-intensity V˙O2 kinetics under conditions of reduced oxygen availability in prepubertal boys.</p>\",\"PeriodicalId\":49712,\"journal\":{\"name\":\"Pediatric Exercise Science\",\"volume\":\" \",\"pages\":\"1-8\"},\"PeriodicalIF\":1.4000,\"publicationDate\":\"2024-06-26\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Pediatric Exercise Science\",\"FirstCategoryId\":\"3\",\"ListUrlMain\":\"https://doi.org/10.1123/pes.2023-0089\",\"RegionNum\":4,\"RegionCategory\":\"医学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"PEDIATRICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Pediatric Exercise Science","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1123/pes.2023-0089","RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"PEDIATRICS","Score":null,"Total":0}
The Influence of Acute Hypoxia on Oxygen Uptake and Muscle Oxygenation Kinetics During Cycling Exercise in Prepubertal Boys.
Purpose: To examine the effect of normobaric hypoxia on pulmonary oxygen uptake (V˙O2) and muscle oxygenation kinetics during incremental and moderate-intensity exercise in children.
Methods: Eight prepubertal boys (9-11 y) performed incremental cycle tests to exhaustion in both normoxia and hypoxia (fraction of inspired O2 of 15%) followed by repeat 6-minute transitions of moderate-intensity exercise in each condition over subsequent visits.
Results: Maximal oxygen uptake (V˙O2max) was reduced in hypoxia compared with normoxia (1.69 [0.20] vs 1.87 [0.26] L·min-1, P = .028), although the gas exchange threshold was not altered in absolute terms (P = .33) or relative to V˙O2max (P = .78). During moderate-intensity exercise, the phase II V˙O2 time constant (τ) was increased in hypoxia (18 [9] vs 24 [8] s, P = .025), with deoxyhemoglobin τ unchanged (17 [8] vs 16 [6], P ≥ .28).
Conclusions: In prepubertal boys, hypoxia reduced V˙O2max and slowed V˙O2 phase II kinetics during moderate-intensity exercise, despite unchanged deoxyhemoglobin kinetics. These data suggest an oxygen delivery dependence of V˙O2max and moderate-intensity V˙O2 kinetics under conditions of reduced oxygen availability in prepubertal boys.
期刊介绍:
Pediatric Exercise Science is a journal committed to enriching the scientific knowledge of exercise during childhood and adolescence. To this end it publishes information that contributes to an understanding of (a) the unique aspects of the physiologic, physical, biochemical, and psychologic responses of children to exercise, (b) the role of exercise in the treatment of pediatric chronic diseases, (c) the importance of physical activity in the prevention of illness and preservation of wellness, and (d) the means by which participation in sports may be made safer and more enjoyable for children and youth. Consideration will be given for publication of work by various methodologies consistent with the scientific approach.
Besides original research, the journal includes review articles, abstracts from other journals, book reviews, and editorial comments. Pediatric Exercise Science encourages the expression of conflicting opinions regarding children and exercise by providing a forum for alternative viewpoints. At the same time it serves as a means of accumulating a base of research information that will allow application of experimental data to clinical practice. The scientific disciplines contributing to this body of knowledge are diverse. Therefore it is the purpose of this journal to provide a common focus for disseminating advances in the science of exercise during childhood. In doing so, the journal allows the opportunity for cross-fertilization of ideas between disciplines that will potentiate the growth of knowledge in this field. Pediatric Exercise Science seeks to stimulate new ideas regarding exercise in children and to increase the awareness of scientists, health care providers, and physical educators of the importance of exercise during childhood.