背景：長距離耐力運動容易導致腸道損傷並破壞腸道的完整性，亦會引發腸胃不適感，而運動中適當地攝取碳水化合物不但能降低腸胃不適，也能減緩腸道損傷。目的：探討長距離跑步中以不同碳水化合物攝取頻率對腸道損傷及腸胃舒適度之影響。方法：採重複量數、平衡次序設計，招募10位有馬拉松經驗之男性，於跑步機上進行 32 公里 65% V̇O2max之固定速度跑步及接續之8公里計時測驗，並於運動中進行每 5 公里攝取 22 克的高頻率攝取 (HCF) 及每 7.5 公里攝取 33 克的低頻率攝取 (LCF) 之不同碳水化合物攝取頻率，但總量皆為 132 克的兩種實驗處理，並測量基準值、運動第30公里及運動後立即之腸道損傷指標(腸道脂肪酸結合蛋白，I-FABP；內毒素)，且於運動前、運動中每10公里及運動後立即測量腸胃舒適度量表 (腹部不適量表，AD；腹部飽足感量表，GF)，比較處理間腸道損傷與腸胃舒適度之差異。結果：(1) I-FABP、內毒素：皆無處理及距離間的交互作用；I-FABP 30~40公里曲線下面積與相對強度呈正相關 (r = 0.455，p < .05)。(2) AD、GF：皆無處理及距離間的交互作用；AD 處理主效果 LCF < HCF (p < .05)；AD 曲線下面積： 30~40 公里，LCF < HCF (p < .05)。(3) I-FABP變化量與腹部不適感的相關為 r = - 0.151 (p > .05)，未達顯著。結論：在 40 公里的跑步運動中，每 5 公里攝取 22 克或每 7.5 公里攝取 33 克碳水化合物並不會影響腸道損傷，但隨著距離增加，腹部不適感會上升，同時高頻率的攝取會有較高的腹部不適感，但不影響運動表現。

Background: Endurance exercise is likely to cause intestinal injury and increase gastrointestinal discomfort. Intaking carbohydrates during exercise can relieve gastrointestinal discomfort and alleviate intestinal injuries. Purpose: To examine the effects of different frequencies of carbohydrate intake on intestinal injury and gastrointestinal comfort during 40 km running. Method: 10 men (PB: 3 hr 8 min ± 17 min, V̇O2max :57.3 ± 5.7 ml/kg/min) were required to perform two trials of the 32 km at 65% V̇O2max following an 8 km time trial. Subjects participated in the following two trials in a counterbalanced, crossover design. 1.HCF (high carbohydrate frequency): 22 grams per 5 km. 2.LCF (low carbohydrate frequency): 33 grams per 7.5 km in (LCF). Total energy gel consumed in both trials were 132g carbohydrate. Plasma intestinal fatty-acid binding protein (I-FABP), endotoxin, and the gastrointestinal comfort scales (abdominal discomfort, AD; gut fullness, GF) were measured. Results: (1) I-FABP, endotoxin: No interactions between treatment and distance; Area under curve of I-FABP in 30-40 km was positively correlated with relative intensity (r = 0.455，p < .05). (2) AD, GF: No interactions between treatment and distance; treatment main effect of AD was LCF < HCF (p < .05); Area under curve of AD was LCF < HCF at 30-40 km (p < .05). (3) No correlation between the change in I-FABP and AD (r = - 0.151, p > .05). Conclusion: In a 40-km run, consuming 22 grams of carbohydrates per 5 km or 33 grams per 7.5 km did not affect intestinal damage. Abdominal discomfort increased with distance and HCF causes higher abdominal discomfort but does not affect performance.

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