Fielding R A, Costill D L, Fink W J, King D S, Hargreaves M, Kovaleski J E
Med Sci Sports Exerc. 1985 Aug;17(4):472-6. doi: 10.1249/00005768-198508000-00012.
Nine men were studied during three 4-h cycling bouts to determine the effect of frequency and dosage of solid carbohydrate (CHO) feedings (86 g) on muscle glycogen utilization and exercise performance. In the frequency trial (F), the subjects ingested 10.75 g of CHO along with 200 ml of water at 30-min intervals; in the dosage trial (D), the subjects ingested 21.5 g of CHO with 400 ml of water at 60-min intervals. During the control trial (C), the subjects ingested 400 ml of an artificially sweetened placebo at 60-min intervals. Respiratory exchange ratios were significantly elevated in both trials D and F (P less than 0.05). Blood glucose was significantly elevated in trial D 20 min post-feeding but had returned to control levels by 50 min. In trial F, blood glucose was maintained at a constant level throughout the entire 4 h. In trial C, blood glucose declined steadily during the entire 4 h. Despite the differences in blood glucose levels between the three trials, there were no significant differences in the rate of muscle glycogen utilization in any of the trials (D = 82.9 +/- 6.6 [SE] mmol X kg-1 vs C = 80.9 +/- 6.9 mmol X kg-1 vs F = 74.4 +/- 12.2 mmol X kg-1). In a sprint ride (100% VO2max) to exhaustion at the end of each trial, the subjects performed significantly longer in trial F compared to C (120.97 +/- 9.6 vs 81.0 +/- 7.1 s).(ABSTRACT TRUNCATED AT 250 WORDS)
对9名男性进行了三次4小时的骑行试验，以确定固体碳水化合物（CHO）喂养的频率和剂量（86克）对肌肉糖原利用和运动表现的影响。在频率试验（F）中，受试者每隔30分钟摄入10.75克CHO和200毫升水；在剂量试验（D）中，受试者每隔60分钟摄入21.5克CHO和400毫升水。在对照试验（C）中，受试者每隔60分钟摄入400毫升人工甜味安慰剂。试验D和F中的呼吸交换率均显著升高（P<0.05）。试验D在喂食后20分钟时血糖显著升高，但在50分钟时已恢复到对照水平。在试验F中，血糖在整个4小时内保持恒定水平。在试验C中，血糖在整个4小时内稳步下降。尽管三次试验的血糖水平存在差异，但任何一次试验中肌肉糖原的利用率均无显著差异（D = 82.9±6.6[SE]mmol·kg-1，C = 80.9±6.9 mmol·kg-1，F = 74.4±12.2 mmol·kg-1）。在每次试验结束时进行的全力冲刺骑行（100%最大摄氧量）至疲劳试验中，与试验C相比，试验F中的受试者表现时间显著更长（120.97±9.6对81.0±7.1秒）。（摘要截短于250字）
