This study determined the influence of a high- (HI) versus low-intensity (LI) cycling warm-up on blood acid-base responses and exercise capacity following ingestion of sodium bicarbonate (SB; 0.3 g/kg body mass) or a placebo (PLA; maltodextrin) 3 hr prior to warm-up. Twelve men (21 ± 2 years, 79.2 ± 3.6 kg body mass, and maximum power output [W_max] 318 ± 36 W) completed a familiarization and four double-blind trials in a counterbalanced order: HI warm-up with SB, HI warm-up with PLA, LI warm-up with SB, and LI warm-up with PLA. LI warm-up was 15 min at 60% W_max, while the HI warm-up (typical of elites) featured LI followed by 2 × 30 s (3-min break) at W_max, finishing 30 min prior to a cycling capacity test at 110% W_max. Blood bicarbonate and lactate were measured throughout. SB supplementation increased blood bicarbonate (+6.4 mmol/L; 95% confidence interval, CI [5.7, 7.1]) prior to greater reductions with HI warm-up (−3.8 mmol/L; 95% CI [−5.8, −1.8]). However, during the 30-min recovery, blood bicarbonate rebounded and increased in all conditions, with concentrations ∼5.3 mmol/L greater with SB supplementation (p < .001). Blood bicarbonate significantly declined during the cycling capacity test at 110%W_max with greater reductions following SB supplementation (−2.4 mmol/L; 95% CI [−3.8, −0.90]). Aligned with these results, SB supplementation increased total work done during the cycling capacity test at 110% W_max (+8.5 kJ; 95% CI [3.6, 13.4], ∼19% increase) with no significant main effect of warm-up intensity (+0.0 kJ; 95% CI [−5.0, 5.0]). Collectively, the results demonstrate that SB supplementation can improve HI cycling capacity irrespective of prior warm-up intensity, likely due to blood alkalosis.

本研究确定了在摄入碳酸氢钠（SB；0.3 g/kg 体重）或安慰剂后，高强度 (HI) 与低强度 (LI) 自行车热身对血液酸碱反应和运动能力的影响（PLA；麦芽糖糊精）预热前 3 小时。12 名男性（21 ± 2 岁，79.2 ± 3.6 kg 体重，最大功率输出 [ W _max ] 318 ± 36 W）以平衡顺序完成了熟悉和四次双盲试验：HI 热身与 SB、HI PLA热身，LI与SB热身，LI与PLA热身。LI 热身是 15 分钟，最大功率为 60% W _，而 HI 热身（典型的精英）的特点是 LI，然后是_最大功率2 × 30 秒（3 分钟休息），在循环容量前 30 分钟完成110% 测试_最大W _ 全程测量血碳酸氢盐和乳酸。SB 补充剂增加了血液碳酸氢盐（+6.4 mmol/L；95% 置信区间，CI [5.7, 7.1]），然后通过 HI 热身（-3.8 mmol/L；95% CI [-5.8, -1.8]）降低更多）。然而，在 30 分钟的恢复过程中，血液碳酸氢盐在所有情况下都会反弹并增加，补充 SB 后浓度会增加约 5.3 mmol/L ( p  < .001)。_{在最大110%} W的循环容量测试期间，血液碳酸氢盐显着下降，SB 补充后下降幅度更大（-2.4 mmol/L；95% CI [-3.8，-0.90]）。与这些结果一致，SB 补充剂增加了在_最大110% W的循环容量测试期间完成的总功（+8.5 kJ；95% CI [3.6, 13.4]，增加 ∼19%），热身强度没有显着的主效应（+0.0 kJ；95% CI [-5.0, 5.0]）。总的来说，结果表明，无论先前的热身强度如何，SB 补充剂都可以提高 HI 循环能力，这可能是由于血液碱中毒。