Conlee R K, Lawler R M, Ross P E
Ann Nutr Metab. 1987;31(2):126-32. doi: 10.1159/000177259.
In athletics, muscle and liver glycogen content is critical to endurance. This study compared the effectiveness of glucose and fructose feeding on restoring glycogen content after glycogen was decreased by exercise (90-min swim) or fasting (24 h). After 2 h of recovery from either exercise or fasting there was no measurable glycogen repletion in red vastus lateralis muscle in response to fructose. In contrast, glucose feeding induced a similar and significant carbohydrate storage after both depletion treatments (8.44 mumol X g-1 X 2 h-1). In the liver, following 2 h of recovery, the rates of glycogen storage were similar after either glucose or fructose ingestion, but fasting caused a greater rate of repletion (83 mumol X g-1 X 2 h-1) than exercise (50 mumol X g-1 X 2 h-1). After 4 h of recovery fructose-fed exercised animals had the highest glycogen concentration (165 mumol X g-1) followed by the glucose-fed exercised group (119 mumol X g-1). These values were 50 and 36%, respectively, of that measured in the normal-fed liver (327 mumol X g-1). In contrast, liver glycogen values in the fasted group decreased between the 2nd and 4th hour of recovery in response to both feeding regimens. From these results we conclude that fructose is a poor nutritional precursor for rapid glycogen restoration in muscle after exercise, but that both glucose and fructose promote rapid accumulation of glycogen in the liver.
在田径运动中，肌肉和肝脏中的糖原含量对耐力至关重要。本研究比较了在糖原因运动（90分钟游泳）或禁食（24小时）而减少后，摄入葡萄糖和果糖对恢复糖原含量的效果。从运动或禁食中恢复2小时后，外侧股四头肌对果糖没有可测量的糖原补充反应。相比之下，在两种消耗处理后，摄入葡萄糖均诱导了相似且显著的碳水化合物储存（8.44 μmol·g⁻¹·2 h⁻¹）。在肝脏中，恢复2小时后，摄入葡萄糖或果糖后的糖原储存速率相似，但禁食导致的补充速率（83 μmol·g⁻¹·2 h⁻¹）高于运动（50 μmol·g⁻¹·2 h⁻¹）。恢复4小时后，喂食果糖的运动动物糖原浓度最高（165 μmol·g⁻¹），其次是喂食葡萄糖的运动组（119 μmol·g⁻¹）。这些值分别是正常喂食肝脏中测量值（327 μmol·g⁻¹）的50%和36%。相比之下，禁食组的肝脏糖原值在恢复的第2小时至第4小时之间，对两种喂食方案均有所下降。从这些结果我们得出结论，运动后果糖作为快速恢复肌肉糖原的营养前体较差，但葡萄糖和果糖都能促进肝脏中糖原的快速积累。
