Int J Sports Physiol Perform. 2021 Dec 1;16(12):1764-1776. doi: 10.1123/ijspp.2020-0847. Epub 2021 May 27.
This study aimed to determine the effects of an acute "train-low" nutritional protocol on markers of recovery optimization compared to standard recovery nutrition protocol.
After completing a 2-hour high-intensity interval running protocol, 8 male endurance athletes consumed a standard dairy milk recovery beverage (CHO; 1.2 g/kg body mass [BM] of carbohydrate and 0.4 g/kg BM of protein) and a low-carbohydrate (L-CHO; isovolumetric with 0.35 g/kg BM of carbohydrate and 0.5 g/kg BM of protein) dairy milk beverage in a double-blind randomized crossover design. Venous blood and breath samples, nude BM, body water, and gastrointestinal symptom measurements were collected preexercise and during recovery. Muscle biopsy was performed at 0 hour and 2 hours of recovery. Participants returned to the laboratory the following morning to measure energy substrate oxidation and perform a 1-hour distance test.
The exercise protocol resulted in depletion of muscle glycogen stores (250 mmol/kg dry weight) and mild body-water losses (BM loss = 1.8%). Neither recovery beverage replenished muscle glycogen stores (279 mmol/kg dry weight) or prevented a decrease in bacterially stimulated neutrophil function (-21%). Both recovery beverages increased phosphorylation of mTORSer2448 (main effect of time = P < .001) and returned hydration status to baseline. A greater fold increase in p-GSK-3βSer9/total-GSK-3β occurred on CHO (P = .012). Blood glucose (P = .005) and insulin (P = .012) responses were significantly greater on CHO (618 mmol/L per 2 h and 3507 μIU/mL per 2 h, respectively) compared to L-CHO (559 mmol/L per 2 h and 1147 μIU/mL per 2 h, respectively). Rates of total fat oxidation were greater on CHO, but performance was not affected.
A lower-carbohydrate recovery beverage consumed after exercise in a "train-low" nutritional protocol does not negatively impact recovery optimization outcomes.
本研究旨在比较标准恢复营养方案与急性“低训”营养方案对恢复优化标志物的影响。
8 名男性耐力运动员在完成 2 小时高强度间歇跑步方案后，以双盲随机交叉设计的方式分别摄入标准乳制恢复饮料（CHO；碳水化合物 1.2g/kg 体重[BM]，蛋白质 0.4g/kg BM）和低碳水化合物（L-CHO；与 0.35g/kg BM 碳水化合物和 0.5g/kg BM 蛋白质等容量的乳制恢复饮料）。在运动前和恢复期间采集静脉血和呼吸样本、裸体 BM、身体水分和胃肠道症状测量值。在恢复 0 小时和 2 小时时进行肌肉活检。参与者第二天早上返回实验室测量能量底物氧化并进行 1 小时距离测试。
运动方案导致肌肉糖原储存耗尽（250mmol/kg 干重）和轻度体液流失（BM 损失=1.8%）。两种恢复饮料均未补充肌肉糖原储存（279mmol/kg 干重）或防止细菌刺激的中性粒细胞功能下降（-21%）。两种恢复饮料均增加 mTORSer2448 的磷酸化（时间的主要效应 P<.001）并使水合状态恢复到基线。CHO 上 p-GSK-3βSer9/总-GSK-3β的倍数增加更大（P=.012）。CHO 上的血糖（P=.005）和胰岛素（P=.012）反应明显大于 L-CHO（分别为 618mmol/L/2h 和 3507μIU/mL/2h）。CHO 上总的脂肪氧化率更高，但运动表现不受影响。
在“低训”营养方案中，运动后摄入较低碳水化合物的恢复饮料不会对恢复优化结果产生负面影响。
