Substrate utilization in boys during exercise with [13C]-glucose ingestion
Substrate utilization in boys during exercise with [13C]-glucose ingestion
复制标题
男孩在摄入 [13C]-葡萄糖的运动过程中的底物利用
DOI：
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发表时间：
2000
影响因子：
3
通讯作者：
G. Heigenhauser
中科院分区：
文献类型：
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作者：
Michael C. Riddell;Oded Bar;H. Schwarcz;G. Heigenhauser
摘要在儿童和青少年长期运动中，葡萄糖摄取对底物利用的影响目前尚不清楚。在本研究中，我们研究了间歇摄入外源性葡萄糖(GLUexo)对13-17 岁青春期男孩在长时间运动中底物利用的影响。健康的未经训练的志愿者在自行车功率计上进行了四次30分钟的运动，中间隔着5分钟的休息时间(≅最大耗氧量的60%)，两次间隔1-4 周。进行了两项试验，一项是对照试验(CT)，受试者在锻炼期间间歇性摄入水，另一项是葡萄糖试验(GT)，受试者在锻炼期间也间歇性地摄入富含13C的GLUexo饮料(≅3 g Glug · kg Body−1)。用间接量热法测定总游离脂肪酸、葡萄糖和碳水化合物的氧化总量，而呼气中的13C/12C比值则根据每轮运动5~10 分钟和25~30 分钟的呼气中13C/12C的比值计算。在相同的时间间隔测定心率和感知劳力等级(RPE)。CT组和GT组CHO总量分别为169.1(12.9) g · 12 0 min−1和203.1(15.9) g · 12 0 min−1(P ； 0.0 1)，脂肪总量分别为31.0(4.2) g · 120 min−1和17.1(2.5) g · 120 min−1(P ； 0.0 1)。GT的GLUexo氧化量为5 7.8(4.3) g · 12 0min −1，占摄入量的34.2(2.2)%。CT组和GT组的内源性葡萄糖氧化量分别为169.1(12.9) g · 12 0 −1和145.3(11.9) g · 12 0min−1(P 和 0.0 1)。GT组的胰岛素和血糖浓度分别比CT组高226%和37%(P <； 0.05)。GT组的游离脂肪酸和甘油浓度分别比CT组低27%和79%(P <； 005)。试验之间心率相似，但在115min和135min时，GT组的RPE均低于CT组。 分钟。因此，在这些实验条件下，GLUexo的摄入分别节省了16%和45%的内源性碳水化合物和脂肪，约占运动总能量需求的25%，并降低了RPE。
Abstract The influence of glucose ingestion on substrate utilization during prolonged exercise in children and adolescents is currently unknown. In the present study we determined the effect of intermittent exogenous glucose (GLUexo) ingestion on substrate utilization during prolonged exercise, in adolescent boys ages 13–17 years. Healthy untrained volunteers performed four 30-min exercise bouts on a cycle ergometer, separated by 5-min rest periods (≅60% maximum O2 consumption), on two occasions spaced 1–4 weeks apart. Two trials were performed, a control trial (CT), in which subjects ingested water intermittently during the exercise, and a glucose trial (GT), in which subjects ingested a 13C-enriched GLUexo drink (≅3 g glucose · kg body mass−1), also intermittently during the exercise. Total free fatty acids (FATtotal), glucose (GLUtotal) and carbohydrate (CHOtotal) oxidation was determined from indirect calorimetry, while GLUexo oxidation was calculated from the 13C/12C ratio in expired air after 5–10 min and 25–30 min of exercise in each bout. Heart rate and rating of perceived exertion (RPE) were determined at the same time intervals. The oxidation of CHOtotal was 169.1 (12.9) g · 120 min−1 and 203.1 (15.9) g · 120 min−1 (P < 0.01) and that of FATtotal was 31.0 (4.2) g · 120 min−1 and 17.1 (2.5) g · 120 min−1 (P < 0.01) in CT and GT, respectively. GLUexo oxidation in GT was 57.8 (4.3) g · 120 min−1, or 34.2 (2.2)% of that ingested. Endogenous glucose oxidation was 169.1 (12.9) g · 120 min−1 and 145.3 (11.9) g · 120 min−1 (P < 0.01) in CT and GT, respectively. Insulin and glucose concentrations were higher in GT than in CT by 226% and 37%, respectively (both P < 0.05). Free fatty acids and glycerol concentrations were lower in GT than in CT, by 27% and 79%, respectively (both P < 0.05). Heart rate was similar between trials, but RPE was lower in GT vs CT at both 115 and 135 min. Thus, under these experimental conditions, GLUexo intake spares endogenous carbohydrate and fat by 16% and 45%, respectively, contributes to approximately 25% of the total energy demand of exercise, and lowers the RPE.