Improvement of [(V)\dot]O_{2 max},\dot{V}\hbox{O}_{2 \max}, by cardiac output and oxygen extraction adaptation during intermittent versus

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• 作者：Fr¨¦d¨¦ric N. Daussin ; Elodie Ponsot ; St¨¦phane P. Dufour ; Evelyne Lonsdorfer-Wolf ; St¨¦phane Doutreleau ; Bernard Geny ; Fran?ois Piquard and Ruddy Richard
• 关键词：Training modality ; Cardiac output ; Arteriovenous difference ; Maximal oxygen consumption ; Sedentary subjects
• 刊名：European Journal of Applied Physiology
• 出版年：2007
• 出版时间：October, 2007
• 年：2007
• 卷：101
• 期：3
• 页码：377-383
• 全文大小：225 KB

文摘

Improvement of exercise capacity by continuous (CT) versus interval training (IT) remains debated. We tested the hypothesis that CT and IT might improve peripheral and/or central adaptations, respectively, by randomly assigning 10 healthy subjects to two periods of 24 trainings sessions over 8 weeks in a cross-over design, separated by 12 weeks of detraining. Maximal oxygen uptake ([(V)\dot]O_{2 max}),(\dot{V}\hbox{O}_{2 \max}), cardiac output ([(Q)\dot]_max)(\dot{Q}_{{\max}}) and maximal arteriovenous oxygen difference (D_{a - [`(v)]</sub> O<sub>2max</sub>)(D_{{\rm a} - {\bar{\rm v}}} \hbox{O}_{2\max}) were obtained during an exhaustive incremental test before and after each training period. [(V)\dot]O<sub>2max</sub>\dot{V}\hbox{O}_{2\max} and [(Q)\dot]<sub>max</sub>\dot{Q}_{{\max}} increased only after IT (from 26.3 ¡À 1.6 to 35.2 ¡À 3.8 ml min−1 kg−1 and from 17.5 ¡À 1.3 to 19.5 ¡À 1.8 l min−1, respectively; P < 0.01). D<sub>a - [`(v)]} O_2maxD_{{\rm a} - {\bar{\rm v}}} \hbox{O}_{2\max} increased after both protocols (from 11.0 ¡À 0.8 to 12.7 ¡À 1.0; P < 0.01 and from 11.0 ¡À 0.8 to 12.1 ¡À 1.0 ml 100 ml−1, P < 0.05 in CT and IT, respectively). At submaximal intensity a significant rightward shift of the [(Q)\dot]/D_{a - [`(v)]}O₂\dot{Q}/D_{{\rm a} - {\bar{\rm v}}}\hbox{O}_{2} relationship appeared only after CT. These results suggest that in isoenergetic training, central and peripheral adaptations in oxygen transport and utilization are training-modality dependant. IT improves both central and peripheral components of [(V)\dot]O_2max\dot{V}\hbox{O}_{2\max} whereas CT is mainly associated with greater oxygen extraction.