Sport, Health and Performance Enhancement Research Group, School of Science and Technology, Nottingham Trent University, Clifton, Nottingham, United Kingdom.
Med Sci Sports Exerc. 2012 May;44(5):863-71. doi: 10.1249/MSS.0b013e31824079d0.
This study examined the effects of different pressure threshold inspiratory loads on lactate clearance and plasma acid-base balance during recovery from maximal exercise.
Eight moderately trained males (V˙O(2peak) = 4.29 ± 0.46 L·min⁻¹) performed, on different days, four maximal incremental cycling tests (power started at 0 W and increased by 20 W·min⁻¹) of identical duration (exercise time during the first trial was 16.32 ± 1.12 min). During 20-min recovery, subjects either rested passively or breathed through a constant pressure threshold inspiratory load of 10 (ITL10), 15 (ITL15), or 20 (ITL20) cm H2O. Plasma lactate concentration ([La⁻]) was measured, and acid-base balance was quantified using the physicochemical approach, which describes the dependency of [H⁺] on the three independent variables: strong ion difference ([Na⁺] + [K⁺] - [Cl⁻] + [La⁻]), the total concentration of weak acids, and the partial pressure of carbon dioxide.
Peak exercise responses were not significantly different between trials. During recovery, the area under the plasma [La] curve was not different between trials (pooled mean = 261 ± 60 mEq) and the [La] measured at the end of the 20-min recovery was also similar (passive recovery = 9.2 ± 3.1 mEq·L⁻¹, ITL10 = 9.3 ± 3.1 mEq·L⁻¹, ITL15 = 8.7 ± 2.8 mEq·L⁻¹, ITL20 = 8.7 ± 3.2 mEq·L⁻¹). Similarly, changes in other strong ions contributing to strong ion difference and total concentration of weak acids, partial pressure of carbon dioxide, and, therefore, [H⁺] were not different between trials.
These data suggest that, in individuals of moderate endurance training status, inspiratory loading at the intensities used in the present study does not accelerate lactate clearance or modify plasma acid-base balance during recovery from maximal exercise.
本研究旨在探讨不同压力阈吸气负荷对最大运动后乳酸清除和血浆酸碱平衡恢复的影响。
8 名中等训练水平的男性（V˙O（2peak）= 4.29 ± 0.46 L·min⁻¹）在不同的日子里进行了 4 次最大递增自行车测试（功率从 0 W 开始，以 20 W·min⁻¹的速度增加），持续时间相同（第一次试验的运动时间为 16.32 ± 1.12 min）。在 20 分钟的恢复期内，受试者要么被动休息，要么通过 10（ITL10）、15（ITL15）或 20（ITL20）cm H2O 的恒定压力阈吸气负荷呼吸。测量血浆乳酸浓度([La⁻])，并使用物理化学方法量化酸碱平衡，该方法描述了[H⁺]与三个独立变量的依赖性：强离子差([Na⁺]+[K⁺]-[Cl⁻]+[La⁻])、弱酸性总浓度和二氧化碳分压。
试验之间的最大运动反应没有显著差异。在恢复期内，血浆[La]曲线下面积在试验之间没有差异（平均为 261 ± 60 mEq），20 分钟恢复期结束时测量的[La]也相似（被动恢复= 9.2 ± 3.1 mEq·L⁻¹，ITL10 = 9.3 ± 3.1 mEq·L⁻¹，ITL15 = 8.7 ± 2.8 mEq·L⁻¹，ITL20 = 8.7 ± 3.2 mEq·L⁻¹）。同样，对强离子差和弱酸性总浓度、二氧化碳分压以及因此[H⁺]有贡献的其他强离子的变化在试验之间也没有差异。
这些数据表明，在中等耐力训练水平的个体中，本研究中使用的强度的吸气负荷不会加速最大运动后乳酸的清除或改变血浆酸碱平衡的恢复。
