补糖对葡萄糖代谢动力学的影响

Effect of Carbohydrate Ingestion on Glucose Kinetics

维持一定的血糖浓度对于持续性耐力运动是有利的,持续性的运动中补充糖可以提高耐力水平,其机制可能和补糖以后血糖浓度得以维持以及补糖后肌糖原利用的减少以减缓糖原的耗竭有关。为了使血糖浓度能够维持,最好使运动前和运动后中,联合补充一定量的糖。关于对糖和中链甘油三酯同时补充对糖代谢动力学的影响,有研究认为同时补充可以节约糖,增加脂肪酸利用,以提高运动能力,但运动强度不能过大,一般需低于60%最大摄氧量。

To keep the blood glucose at a certain level is of benefit to the prolonged endurance exercise. Many studies have shown that the ingestion of CHO during prolonged exercise enhances endurance performance, but the underlying mechanisms are still incompletely understood. The experimental evidence collected during the past suggests two possible mechanisms that could be responsible for the effect of CHO ingestion during prolonged submaximal exercise. The first is the improved performance by the maintenance of high blood glucose levels, especially late in exercise. The second mechanism could be a reduced rate of muscle glycogen utilization, which would delay the depletion of the glycogen stores and hence the onset of fatigue. Ingestion of CHO^+medium-chain trigylcerides (MCT) has been advocated as a possible means of enhancing exercise performance during prolonged endurance events(≤60% O2 peak). The mechanism may be that the ingested MCT increase fat oxidation, and spare muscle glycogen.