Section of Integrative Physiology, Department of Nutrition, Exercise and Sports (NEXS), University of Copenhagen, Copenhagen Ø, Denmark.
Acta Physiol (Oxf). 2021 Mar;231(3):e13580. doi: 10.1111/apha.13580. Epub 2020 Dec 2.
To assess how blood-flow-restricted (BFR) interval-training affects the capacity of the leg muscles for pH regulation during dynamic exercise in physically trained men.
Ten men (age: 25 ± 4y; : 50 ± 5 mL∙kg ∙min ) completed a 6-wk interval-cycling intervention (INT) with one leg under BFR (BFR-leg; ~180 mmHg) and the other without BFR (CON-leg). Before and after INT, thigh net H -release (lactate-dependent, lactate-independent and sum) and blood acid/base variables were measured during knee-extensor exercise at 25% (Ex25) and 90% (Ex90) of incremental peak power output. A muscle biopsy was collected before and after Ex90 to determine pH, lactate and density of H -transport/buffering systems.
After INT, net H release (BFR-leg: 15 ± 2; CON-leg: 13 ± 3; mmol·min ; Mean ± 95% CI), net lactate-independent H release (BFR-leg: 8 ± 1; CON-leg: 4 ± 1; mmol·min ) and net lactate-dependent H release (BFR-leg: 9 ± 3; CON-leg: 10 ± 3; mmol·min ) were similar between legs during Ex90 (P > .05), despite a 142% lower muscle intracellular-to-interstitial lactate gradient in BFR-leg (-3 ± 4 vs 6 ± 6 mmol·L ; P < .05). In recovery from Ex90, net lactate-dependent H efflux decreased in BFR-leg with INT (P < .05 vs CON-leg) owing to lowered muscle lactate production (58% vs CON-leg, P < .05). Net H gradient was not different between legs (19%, P > .05; BFR-leg: 48 ± 30; CON-leg: 44 ± 23; mmol·L ). In BFR-leg, NHE1 density was higher than in CON-leg (45%; P < .05) and correlated with total-net H -release (r = 0.71; P = .031) and lactate-independent H release (r = 0.74; P = .023) after INT, where arterial [ ] and standard base excess in Ex25 were higher in BFR-leg than CON-leg.
Compared to a training control, BFR-interval training increases the capacity for pH regulation during dynamic exercise mainly via enhancement of muscle lactate-dependent H -transport function and blood H -buffering capacity.
评估血流限制（BFR）间歇训练如何影响经过训练的男性在动态运动中腿部肌肉的 pH 值调节能力。
10 名男性（年龄：25 ± 4 岁；最大摄氧量：50 ± 5 mL·kg·min）完成了 6 周的间歇骑车干预（INT），一条腿采用 BFR（BFR 腿；约 180mmHg），另一条腿不采用 BFR（CON 腿）。在 INT 前后，在 25%（Ex25）和 90%（Ex90）递增峰值功率输出下，测量股四头肌伸肌运动时的大腿净 H 释放（乳酸依赖型、乳酸非依赖型和总和）和血液酸碱变量。在 Ex90 前后采集肌肉活检，以确定 pH 值、乳酸和 H 转运/缓冲系统的密度。
INT 后，Ex90 期间 BFR 腿的净 H 释放（BFR 腿：15 ± 2；CON 腿：13 ± 3；mmol·min）、净乳酸非依赖型 H 释放（BFR 腿：8 ± 1；CON 腿：4 ± 1；mmol·min）和净乳酸依赖型 H 释放（BFR 腿：9 ± 3；CON 腿：10 ± 3；mmol·min）相似（P >.05），尽管 BFR 腿的肌肉细胞内-细胞间乳酸梯度低约 142%（-3 ± 4 对 6 ± 6 mmol·L；P <.05）。在 Ex90 恢复期间，由于肌肉乳酸生成降低（58%对 CON 腿，P <.05），BFR 腿的 INT 后，乳酸依赖型 H 外流减少（P <.05 对 CON 腿）。净 H 梯度在两腿之间没有差异（19%，P >.05；BFR 腿：48 ± 30；CON 腿：44 ± 23；mmol·L）。BFR 腿的 NHE1 密度高于 CON 腿（~45%；P <.05），与总净 H 释放（r = 0.71；P = 0.031）和乳酸非依赖型 H 释放（r = 0.74；P = 0.023）相关，INT 后，BFR 腿的动脉[ ]和 Ex25 标准基础过剩高于 CON 腿。
与训练对照相比，BFR 间歇训练通过增强肌肉乳酸依赖型 H 转运功能和血液 H 缓冲能力，增加了动态运动中 pH 值调节的能力。
