Sareban Mahdi, Zügel David, Koehler Karsten, Hartveg Paul, Zügel Martina, Schumann Uwe, Steinacker Jürgen Michael, Treff Gunnar
Division of Sports and Rehabilitation Medicine, University of Ulm, Ulm, Germany.
Int J Sport Nutr Exerc Metab. 2016 Apr;26(2):114-22. doi: 10.1123/ijsnem.2015-0060. Epub 2015 Aug 31.
The ingestion of exogenous carbohydrates (CHO) during prolonged endurance exercise, such as long-distance triathlon, is considered beneficial with regard to performance. However, little is known about whether this performance benefit differs among different forms of CHO administration. To this end, the purpose of our study was to determine the impact of CHO ingestion from a semisolid source (GEL) on measures of performance and gastrointestinal (GI) comfort compared with CHO ingestion from a liquid source (LIQ). Nine well-trained triathletes participated in this randomized crossover study. Each participant completed a 60-min swim, 180-min bike exercise, and a 60-min all-out run in a laboratory environment under 2 conditions, once while receiving 67.2 ± 7.2 g · h-1 (M ± SD) of CHO from GEL and once while receiving 67.8 ± 4.2 g · h-1 of CHO from LIQ. The amount of fluid provided was matched among conditions. Respiratory exchange ratio (RER), blood glucose, and lactate as well as GI discomfort were assessed at regular intervals during the experiment. The distance covered during the final all-out run was not significantly different among participants ingesting GEL (11.81 ± 1.38 km) and LIQ (11.91 ± 1.53 km; p = .89). RER, blood glucose, and lactate did not differ significantly at any time during the experiment. Seven participants reported GI discomfort with GEL, and no athlete reported GI discomfort with LIQ (p = .016). This study suggests that administration of GEL does not alter long-distance triathlon performance when compared with LIQ, but GEL seems to be associated with reduced GI tolerance. Athletes should consider this a potential disadvantage of GEL administration during long-distance triathlon.
在长时间耐力运动（如长距离铁人三项）中摄入外源性碳水化合物（CHO）被认为对运动表现有益。然而，对于不同形式的CHO给药，这种对运动表现的益处是否存在差异知之甚少。为此，我们研究的目的是确定与从液体来源（LIQ）摄入CHO相比，从半固体来源（GEL）摄入CHO对运动表现指标和胃肠道（GI）舒适度的影响。九名训练有素的铁人三项运动员参与了这项随机交叉研究。每位参与者在实验室环境中的两种条件下完成了60分钟的游泳、180分钟的自行车运动和60分钟的全力跑，一次是从GEL中摄入67.2±7.2克·小时-1（平均值±标准差）的CHO，另一次是从LIQ中摄入67.8±4.2克·小时-1 的CHO。各条件下提供的液体量相匹配。在实验过程中定期评估呼吸交换率（RER）、血糖、乳酸以及胃肠道不适情况。在摄入GEL的参与者（11.81±1.38千米）和摄入LIQ的参与者（11.91±1.53千米；p = 0.89）中，最后全力跑的距离没有显著差异。在实验期间的任何时间，RER、血糖和乳酸均无显著差异。七名参与者报告服用GEL时有胃肠道不适，而没有运动员报告服用LIQ时有胃肠道不适（p = 0.016）。这项研究表明，与LIQ相比，服用GEL不会改变长距离铁人三项的运动表现，但GEL似乎与胃肠道耐受性降低有关。运动员应将此视为长距离铁人三项中服用GEL的一个潜在缺点。
