Effects of training on muscle O2 transport at VO2max.
Effects of training on muscle O2 transport at VO2max.
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最大摄氧量训练对肌肉 O2 运输的影响。
DOI：
10.1152/jappl.1992.73.3.1067
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发表时间：
1992
期刊：
影响因子：
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通讯作者：
Wagner,PD
中科院分区：
文献类型：
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作者：
Roca,J;Agusti,AG;Alonso,A;Poole,DC;Viegas,C;Barbera,JA;Rodriguez-Roisin,R;Ferrer,A;Wagner,PD
对12名久坐不动的受试者(年龄21.8+/-3.4岁，最大摄氧量(VO2max)36.9+/-5.9ml.min-1·kg-1)进行耐力训练9wk后腿部最大吸氧量(VO2Leg)增加的定量研究。当受试者呼吸室内空气、15%O2和12%O2时，测量VO2max、腿部血流量(Qleg)、动脉和股静脉PO2，从而测量VO2腿。这三个海盗的顺序是平衡的。训练后，VO2max和VO2Leg在每个吸入O2浓度时都有所增加[FiO2；高于3个FiO2值的平均值分别为25.2+/-17.8和36.5+/-33%(SD)]。训练前，VO2腿与平均毛细血管PO2在低氧时呈线性相关，但在室内空气呼吸时不呈线性相关，提示在21%O2时，VO2max不受氧气供应的限制。训练后，每个FiO2的VO2腿和平均毛细血管PO2沿着一条直线下降，没有截距，就像运动员一样(Roca等人。J.Appl.物理。67：291-299,1989)。计算的肌肉氧弥散能力(DO2)增加了34%，而Qleg增加了19%。相对较大的DO2上升增加了DO2/QLeg，从而导致O2提取增加9.9%。通过数值分析，仅增加QLeg(恒定的DO2)将使VO2腿增加35ml/min(平均值)，而增加DO2(恒定的QLeg)将使VO2增加85ml/min，增加一倍以上。这些个体效应的总和(120ml/分钟)小于观察到的164ml/分钟的平均升高(P=0.013)。这种协同作用(由DO2/QLeg的增加解释)似乎是训练中VO2max增加的重要贡献。
To quantify the relative contributions of convective and peripheral diffusive components of O2 transport to the increase in leg O2 uptake (VO2leg) at maximum O2 uptake (VO2max) after 9 wk of endurance training, 12 sedentary subjects (age 21.8 +/- 3.4 yr, VO2max 36.9 +/- 5.9 ml.min-1.kg-1) were studied. VO2max, leg blood flow (Qleg), and arterial and femoral venous PO2, and thus VO2leg, were measured while the subjects breathed room air, 15% O2, and 12% O2. The sequence of the three inspirates was balanced. After training, VO2max and VO2leg increased at each inspired O2 concentration [FIO2; mean over the 3 FIO2 values 25.2 +/- 17.8 and 36.5 +/- 33% (SD), respectively]. Before training, VO2leg and mean capillary PO2 were linearly related through the origin during hypoxia but not during room air breathing, suggesting that, at 21% O2, VO2max was not limited by O2 supply. After training, VO2leg and mean capillary PO2 at each FIO2 fell along a straight line with zero intercept, just as in athletes (Roca et al. J. Appl. Physiol. 67: 291–299, 1989). Calculated muscle O2 diffusing capacity (DO2) rose 34% while Qleg increased 19%. The relatively greater rise in DO2 increased the DO2/Qleg, which led to 9.9% greater O2 extraction. By numerical analysis, the increase in Qleg alone (constant DO2) would have raised VO2leg by 35 ml/min (mean), but that of DO2 (constant Qleg) would have increased VO2leg by 85 ml/min, more than twice as much. The sum of these individual effects (120 ml/min) was less (P = 0.013) than the observed rise of 164 ml/min (mean). This synergism (explained by the increase in DO2/Qleg) seems to be an important contribution to increases in VO2max with training.