在耐力运动期间补充碳水化合物(CHO)可以提高性能。然而,目前尚不清楚低血糖指数(GI)CHO与标准高GICHO相比是否会导致不同的体感和代谢作用.这项研究调查了CHO补充不同GI的体格力和代谢作用,即,(a)海藻糖(30克/小时),(b)异麦芽酮糖(30克/小时),(c)麦芽糊精(60克/小时),和(d)安慰剂(水)。在这个双盲中,交叉,平衡,安慰剂对照研究,13名男性骑自行车的人在不同的运动强度下总共骑了100分钟(即,在1.5、2.0和2.5W/kg下进行10分钟阶段;在协议之前和之后以1.0W/kg重复三次,再加上两个5分钟阶段),随后在四个不同的场合进行了20分钟的时间试验。血糖和乳酸(每20分钟),心率,并在整个过程中收集了感知到的劳累等级,运动前和运动后立即进行肌肉活检。结果表明,与安慰剂相比,海藻糖改善了计时试验性能(总工作量302±39vs.287±48kJ;p=.01),会话之间没有其他差异(所有p≥.07)。在整个100分钟的协议中,与其他补充剂相比,麦芽糊精在所有时间点的血糖均较高(所有p<0.05)。心率,感知努力的评级,肌肉糖原含量,血糖,当考虑20分钟时间试验时,乳酸和乳酸在不同条件下没有差异(所有p>.05)。在整个耐力运动中补充海藻糖可改善自行车性能,并且似乎是长达2小时的运动任务的合适CHO来源。在不同类型的CHO之间没有建立体因性优势。
Carbohydrate (CHO) supplementation during endurance exercise can improve performance. However, it is unclear whether low glycemic index (GI) CHO leads to differential ergogenic and metabolic effects compared with a standard high GI CHO. This
study investigated the ergogenic and metabolic effects of CHO supplementation with distinct GIs, namely, (a) trehalose (30 g/hr), (b) isomaltulose (30 g/hr), (c) maltodextrin (60 g/hr), and (d) placebo (water). In this double-blind, crossover, counterbalanced, placebo-controlled
study, 13 male cyclists cycled a total of 100 min at varied exercise intensity (i.e., 10-min stages at 1.5, 2.0, and 2.5 W/kg; repeated three times plus two 5-min stages at 1.0 W/kg before and after the protocol), followed by a 20-min time
trial on four separated occasions. Blood glucose and lactate (every 20 min), heart rate, and ratings of perceived exertion were collected throughout, and muscle biopsies were taken before and immediately after exercise. The results showed that trehalose improved time-
trial performance compared with placebo (total work done 302 ± 39 vs. 287 ± 48 kJ; p = .01), with no other differences between sessions (all p ≥ .07). Throughout the 100-min protocol, blood glucose was higher with maltodextrin compared with the other supplements at all time points (all p < .05). Heart rate, ratings of perceived exertion, muscle glycogen content, blood glucose, and lactate were not different between conditions when considering the 20-min time
trial (all p > .05). Trehalose supplementation throughout endurance exercise improved cycling performance and appears to be an appropriate CHO source for exercise tasks up to 2 hr. No ergogenic superiority between the different types of CHO was established.