PDF(Pubmed)
Abstract：
Relative to carbohydrate (CHO) alone, exogenous ketones followed by CHO supplementation during recovery from glycogen-lowering exercise have been shown to increase muscle glycogen resynthesis. However, whether this strategy improves subsequent exercise performance is unknown. The objective of this study was to assess the efficacy of ketone monoester (KME) followed by CHO ingestion after glycogen-lowering exercise on subsequent 20 km (TT20km) and 5 km (TT5km) best-effort time trials. Nine recreationally active men (175.6 ± 5.3 cm, 72.9 ± 7.7 kg, 28 ± 5 y, 12.2 ± 3.2% body fat, VO2max = 56.2 ± 5.8 mL· kg BM-1·min-1; mean ± SD) completed a glycogen-lowering exercise session, followed by 4 h of recovery and subsequent TT20km and TT5km. During the first 2 h of recovery, participants ingested either KME (25 g) followed by CHO at a rate of 1.2 g·kg-1·h-1 (KME + CHO) or an iso-energetic placebo (dextrose) followed by CHO (PLAC + CHO). Blood metabolites during recovery and performance during the subsequent two-time trials were measured. In comparison to PLAC + CHO, KME + CHO displayed greater (p < 0.05) blood beta-hydroxybutyrate concentration during the first 2 h, lower (p < 0.05) blood glucose concentrations at 30 and 60 min, as well as greater (p < 0.05) blood insulin concentration 2 h following ingestion. However, no treatment differences (p > 0.05) in power output nor time to complete either time trial were observed vs. PLAC + CHO. These data indicate that the metabolic changes induced by KME + CHO ingestion following glycogen-lowering exercise are insufficient to enhance subsequent endurance time trial performance.
摘要：
相对于单独的碳水化合物（CHO），从降低糖原的运动中恢复过程中补充外源性酮，然后补充CHO已被证明可以增加肌肉糖原的再合成。然而,该策略是否能改善后续运动表现尚不清楚.这项研究的目的是评估酮单酯（KME）在随后的20km（TT20km）和5km（TT5km）尽最大努力时间试验中降低糖原运动后摄入CHO的功效。9名从事娱乐活动的男性（175.6±5.3厘米，72.9±7.7kg,28±5y，12.2±3.2%的体脂，VO2max=56.2±5.8mL·kgBM-1·min-1；平均值±SD）完成了降低糖原的运动，随后是4小时的恢复和随后的TT20km和TT5km。在恢复的前2小时内，参与者以1.2g·kg-1·h-1(KME+CHO)或等能量安慰剂(右旋糖),随后摄入CHO(PLAC+CHO),随后摄入KME(25g).测量了恢复期间的血液代谢产物和随后的两次试验期间的性能。与PLAC+CHO相比，KME+CHO在最初2小时内显示出更高的血液β-羟基丁酸浓度(p<0.05)，在30和60分钟时降低（p<0.05）血糖浓度，以及更高的（p<0.05）血胰岛素浓度2小时后摄入。然而,未观察到功率输出或完成任一时间试验的时间与治疗差异（p>0.05）。PLAC+CHO。这些数据表明，降低糖原运动后摄入KMECHO引起的代谢变化不足以增强随后的耐力试验表现。
