Ivy J L, Costill D L, Fink W J, Lower R W
Med Sci Sports. 1979 Spring;11(1):6-11.
Nine trained cyclists were studied to determine the effects of caffeine (CAF), and glucose polymer (GP) feedings on work production (kpm) during two hr of isokinetic cycling exercise (80 rpm). Ingestion of 250 mg of CAF 60 min prior to the ride was followed by ingestion of an additional 250 mg fed at 15 min intervals over the first 90 min of the exercise. This treatment significantly increased work production by 7.4% and Vo2 by 7.3% as compared to control (C) while the subjects' perception of exertion remained unchanged. Ingestion of approximately 90 g of GP during the first 90 min (12.8 g/15 min) of the exercise had no effect on total work production or Vo2. It was, however, effective in reducing the rate of fatigue over the last 30 min of cycling. Although GP maintained blood glucose and insulin levels (P less than or equal to 0.05) above those of the C and CAF trials, total CHO utilization did not differ between treatments. During the last 70 min of the CAF trial, however, fat oxidation was elevated 31% and appeared to provide the substrate needed for the increased work production during this period of exercise. These data, therefore, demonstrate an enhanced rate of lipid catabolism and work production following the ingestion of caffeine.
对9名训练有素的自行车运动员进行了研究，以确定在两小时的等速骑行运动（80转/分钟）期间，摄入咖啡因（CAF）和葡萄糖聚合物（GP）对做功量（千克力·米）的影响。骑行前60分钟摄入250毫克CAF，随后在运动的前90分钟内每隔15分钟额外摄入250毫克。与对照组（C）相比，这种处理使做功量显著增加了7.4%，耗氧量增加了7.3%，而受试者的用力感知保持不变。在运动的前90分钟（12.8克/15分钟）摄入约90克GP对总做功量或耗氧量没有影响。然而，它有效地降低了骑行最后30分钟的疲劳率。尽管GP使血糖和胰岛素水平（P≤0.05）维持在高于C组和CAF组试验的水平，但各处理之间的总碳水化合物利用率没有差异。然而，在CAF试验的最后70分钟，脂肪氧化增加了31%，似乎为这段运动期间增加的做功量提供了所需的底物。因此，这些数据表明摄入咖啡因后脂质分解代谢率和做功量有所提高。
