Miall A, Khoo A, Rauch C, Snipe R M J, Camões-Costa V L, Gibson P R, Costa R J S
Department of Nutrition Dietetics & Food, Monash University, Notting Hill, Vic., Australia.
Department of Gastroenterology- The Alfred Hospital, Monash University, Melbourne, Vic., Australia.
Scand J Med Sci Sports. 2018 Feb;28(2):630-640. doi: 10.1111/sms.12912. Epub 2017 Jun 19.
Debilitating gastrointestinal symptoms is a common feature of endurance running and may be exacerbated by and/or limit the ability to tolerate carbohydrate intake during exercise. The study aimed to determine whether two weeks of repetitive gut-challenge during running can reduce exercise-associated gastrointestinal symptoms and carbohydrate malabsorption. Endurance runners (n=18) performed an initial gut-challenge trial (GC1) comprising 2-hour running exercise at 60% VO (steady state) while consuming a formulated gel-disk containing 30 g carbohydrates (2:1 glucose-fructose, 10% w/v) every 20 minutes, followed by a 1-hour running effort bout. Gastrointestinal symptoms, feeding tolerance, and breath hydrogen (H ) were determined along the gut-challenge trial. After GC1, participants were randomly assigned to a blinded carbohydrate (CHO, 90 gCHO hour ) or placebo (PLA, 0 gCHO hour ) gut-training group. This comprised of consuming the group-specific feeding intervention during 1-hour running exercise at 60% VO equivalent, daily over a period of two weeks. Participants then repeated the gut-challenge trial (GC2). In GC2, a reduced gut discomfort (P=.012), total (P=.009), upper- (P=.015), and lower-gastrointestinal (P=.008) symptoms, and nausea (P=.05) were observed on CHO, but not PLA. Feeding tolerance did not differ between GC1 and GC2 on CHO and PLA. H peak was attenuated in GC2 (6±3 ppm) compared to GC1 (13±6 ppm) on CHO (P=.004), but not on PLA (GC1 11±7 ppm, and GC2 10±10 ppm). The effort bout distance was greater in GC2 (12.3±1.3 km) compared with GC1 (11.7±1.5 km) on CHO (P=.035) only. Two weeks of repetitive gut-challenge improve gastrointestinal symptoms and reduce carbohydrate malabsorption during endurance running, which may have performance implications.
使人虚弱的胃肠道症状是耐力跑的一个常见特征，并且可能会因运动期间碳水化合物摄入而加重和/或限制耐受能力。该研究旨在确定在跑步期间进行两周的重复性肠道挑战是否可以减轻与运动相关的胃肠道症状和碳水化合物吸收不良。耐力跑者（n = 18）进行了初始肠道挑战试验（GC1），包括在60%VO₂（稳态）下进行2小时的跑步运动，同时每20分钟食用一片含有30克碳水化合物（葡萄糖-果糖比例为2:1，10%w/v）的特制凝胶片，随后进行1小时的跑步冲刺。在肠道挑战试验过程中测定胃肠道症状、进食耐受性和呼出气氢气（H₂）。在GC1之后，参与者被随机分配到一个盲法碳水化合物（CHO，90克CHO/小时）或安慰剂（PLA，0克CHO/小时）肠道训练组。这包括在两周的时间内，每天在60%VO₂等效强度下进行1小时的跑步运动时食用特定组别的进食干预物。然后参与者重复肠道挑战试验（GC2）。在GC2中，观察到在CHO组而非PLA组出现肠道不适减轻（P = 0.012）、总体（P = 0.009）、上胃肠道（P = 0.015）和下胃肠道（P = 0.008）症状以及恶心（P = 0.05）减轻。在CHO组和PLA组中，GC1和GC2之间的进食耐受性没有差异。与GC1相比，CHO组在GC2中的H₂峰值减弱（6±3 ppm对比13±6 ppm，P = 0.004），但PLA组没有（GC1为11±7 ppm，GC2为10±10 ppm）。仅在CHO组中，GC2中的冲刺跑距离比GC1更长（12.3±1.3千米对比11.7±1.5千米，P = 0.035）。两周的重复性肠道挑战可改善耐力跑期间的胃肠道症状并减少碳水化合物吸收不良，这可能对运动表现有影响。
