共查询到19条相似文献,搜索用时 650 毫秒
1.
不同热源质比例膳食餐后血糖水平及葡萄糖负荷的影响 总被引:2,自引:0,他引:2
为了探索能够在较长时间内维持较高血糖水平的膳食,以利于长途飞行,我们设计了总热量相当的4种不同热源质比例试验早餐,观察餐后血糖水平的变化以及给一定葡萄糖负荷对餐后血糖水平的影响。实验对象为20名健康男性,结果表明,进食高碳水化合物餐后血糖水平呈先升高后下降趋势;高蛋白质餐后血糖水平先稍有下降然后逐渐升高且持续时间长;高脂肪餐后血糖水平低而平;现行空勤餐后血糖水平基本趋势与高碳水化合物相似,但变化幅 相似文献
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目的:探讨高糖餐后进行急性有氧运动对健康青年男性血糖及胰岛素水平的影响。方法:11名健康青年男性进行平衡随机交叉自身对照实验,包括口服葡萄糖耐量试验(OGTT)(用OGTT表示)和在OGTT后即刻进行一次45分钟的中等强度有氧运动(用OGTT EX表示)。抽取空腹及服用葡萄糖后1、2、3和4小时的肘静脉血,测定血清血糖和胰岛素水平,并分别计算血糖和胰岛素曲线下面积。结果:OGTT EX和OGTT实验后1h的胰岛素水平有显著性差异(P<0.05),胰岛素曲线下面积也有显著性差异(P<0.05),但其血糖及血糖曲线下面积的差异无显著性(P值分别为0.9466和0.9556)。结果表明,高糖餐后进行急性有氧运动可抑制胰岛素水平升高。 相似文献
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实验性2型糖尿病大鼠模型的建立和评价(Ⅰ)——体重、血糖和肝糖原的变化 总被引:5,自引:3,他引:2
目的:用高脂饲料加小剂量STZ腹腔注射建立实验性2型糖尿病大鼠模型。方法:采用Wistar大鼠,分为正常对照组、高脂饲料组、小剂量STZ组(30 mg/kg)和高脂饲料加小剂量STZ(30 mg/kg)组,每10 d测定大鼠体重、空腹血糖和肝糖原等指标,连续50 d,对各组大鼠上述指标进行比较和评价。结果:①体重:高脂饲料组大鼠体重呈连续上升趋势,小剂量STZ组和高脂饲料加小剂量STZ组大鼠体重呈先降低再恢复的趋势;②空腹血糖:高脂饲料组大鼠空腹血糖轻微升高,小剂量STZ组大鼠空腹血糖呈上升的趋势,高脂饲料加小剂量STZ组大鼠空腹血糖呈明显上升趋势;③肝糖原:高脂饲料组大鼠肝糖原明显升高,小剂量STZ组、高脂饲料加小剂量STZ组大鼠肝糖原未见明显改变;结论:高脂饲料加小剂量STZ腹腔注射能成功诱导2型糖尿病大鼠模型,这种造模方法具有成模后血糖维持在较高水平、自身缓解较少、症状较轻和动物状态良好等优点。 相似文献
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目的 观察脂肪负荷餐后富含甘油三酯的脂蛋白(TRL)和红细胞聚集性的动态变化。方法 50名飞行员分为试验组和对照组,每组25人,试验组在定量进食早餐的基础上加服脂肪负荷餐;对照组仅定量进食早餐。空腹及餐后3和8h各测定甘油三酯(TG)和高密度脂蛋白-胆固醇(HDL-C)水平,同时测定4项红细胞参数和4项红细胞聚集参数。结果 与空腹水平相比,试验组餐后3h TG升高、HDL-C降低(P<0.01)。餐后8h TG恢复至空腹水平(P>0.05),但HDL-C未升至空腹水平(P<0.01)。与空腹测定值相比,试验组餐后3和8h红细胞比容和4项红细胞聚集参数增高(P<0.01或P<0.05)。对照组空腹、餐后3和8h上述指标差异无显著性意义(P>0.05)。结论 脂肪负荷餐后在高TG/低HDL-C血症的同时,存在红细胞聚集力增强,延续时间更长。 相似文献
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目的 采用动态血糖监测系统(CGMS)研究不同糖调节受损人群的餐后血糖波动特征.方法 根据连续2次75g口服葡萄糖耐量检查(OGTT)结果,选取北京地区稳定人群中正常糖耐量(NGT)组22例,单纯空腹血糖受损(HFG)15例、单纯糖耐量低减(I-IGT)19例、空腹血糖受损合并糖耐量低减(IFG/IGT)组11例,新诊断2型糖尿病(T2DM)组21例.所有受试对象均行72hCGMS监测,分析比较各组餐后血糖峰值(PPG)、达峰时间(△t).餐后血糖波动幅度(PPGE)、餐后血糖波动持续时间(DPE)、曲线下面积(AUC)和其增量(△AUC).结果 I-IGT、IFG/IGT和T2DM组的餐后PPG、餐后PFGE较NGT或I-IFG明显升高,HGT和T2DM组DPE明显延长,T2DM组△t较NGT组明显延迟(P<0.05);从NGT、I-IGT、IFG/IGT到T2DM组,餐后血糖对全天高血糖的贡献率(△PAUCI)逐渐下降;且I-IFG、IRG/IGT和T2DM组较NGT有显著性差异(P<0.05);当糖化血蛋白(HbA1C)≥7%时,空腹对全天高血糖的贡献率首次逆转为大于餐后贡献率,且与HbA1C<5.5%组比较,△PAUC1开始有显著性差异;HbA1C与餐后总曲线下面积(AUC1)、全天总曲线下面积(AUC2)、空腹总曲线下面积(AUC3)、OGTT葡萄糖负荷后2h血糖(2hPBG)和3餐血糖峰值均值(MPPG)显著相关(γ分别为0.743、0.687、0.504、0.708和0.732,P<0.001);以HbA1C为因变量,以曲线下面积和血糖水平为自变量分别进行多元逐步回归分析,只有AUC1、AUC2和2hPBG、中餐后PPG最终分别进入2个方程(决定系数r2为0.552和0.614,P<0.01).结论 IGR三组分中I-IFG的餐后特征与NGT最为接近,I-IGT组与T2DM最相似;除I-IFG组外,随着糖调节受损程度的加重,餐后血糖对全天高血糖的贡献率逐渐下降;当HbA1C<7%时,应以控制餐后血糖为主,餐后2h血糖为推荐的简单评价指标;而HbA1C≥7%时,还应重视空腹血糖. 相似文献
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飞行员脂肪耐量调查 总被引:8,自引:3,他引:5
目的探讨飞行员脂肪负荷餐后富含甘油三酯的脂蛋白(TRL)清除延迟发生率,TRL清除延迟与血浆高密度脂蛋白胆固醇(HDL-C)、纤维蛋白原(FIB)及一氧化氮(NO)的关系.方法62名飞行员作为调查对象,测定其空腹12h后和服黄油试验餐(黄油量1.3g/kg体重)后血浆甘油三酯(TG)、HDL-C、FIB和NO水平.结果62名飞行员TRL清除延迟发生率为43.5%,其餐后8hTG水平平均为空腹的2.5倍,差异有显著性意义(P<0.01);FIB水平升高(P<0.01)HDL水平下降(P<0.05);餐后8h血浆NO水平与空腹水平差异无显著性意义(P>0.05).结论飞行员脂肪负荷餐后TRL清除延迟发生率明显高于招飞学员的发生率(5%).血浆高HDL-C水平可能具有抗TRL清除延迟的作用.应注意TRL清除延迟与低HDL-C、高FIB血症等致动脉粥样硬化危险因素的综合防治. 相似文献
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目的:观察地尔硫艹卓(Dil)对空腹大鼠,葡萄糖负荷大鼠以及肾上腺素诱发高血糖大鼠血糖水平的影响。方法采用葡萄糖氧化酶法测定血糖含量。结果:Dil10mg·kg-1 和100mg·kg-1ig 使空腹大鼠血糖水平显著升高,Dil100mg·kg-1 给药30min 后,血糖水平与对照组相比升高了45% 。在糖耐量试验中,Dil10mg·kg- 1 和100mg·kg-1ig 显著改善糖耐量。Dil10mg·kg-1 和100mg·kg-1ig 剂量依赖性加重肾上腺素诱发的高血糖反应。结论:提示,Dil 临床剂量升高空腹及肾上腺素诱发高血糖大鼠血糖水平,改善葡萄糖负荷大鼠糖耐量 相似文献
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地尔硫zhuo对正常大鼠和高血糖大鼠血糖水平的影响 总被引:1,自引:1,他引:0
目的:观察地尔硫zhuo(Dil)对空腹大鼠,葡萄糖负荷大鼠以及肾上腺素诱发高血糖大鼠血糖水平的影响。方法:采用葡萄糖氧化酶法测定血糖含量。结果:Dil 10mg·kg^-1和l00mg·kg^-1 ig使空腹大鼠血糖水平显升高,Dil 100mg·kg^-1给药30min后,血糖水平与对照组相比升高了45%。在糖耐量试验中,Dil l0mg·kg^-1和100mg·kg^-1 ig显改善糖耐量。Dil 10mg·kg^-1和l00mg·kg^-1 ig剂量依赖性加重肾上腺素诱发的高血糖反应。结论:提示,Dil临床剂量升高空腹及肾上腺素诱发高血糖大鼠血糖水平,改善葡萄糖负荷大鼠糖耐量。 相似文献
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飞行员脂肪负荷餐后血浆脂质代谢异常分析 总被引:2,自引:0,他引:2
目的:应用脂肪耐量试验分析飞行员富含甘油三酯的脂蛋白(TRL)清除延迟发生率及其对血浆脂质的影响,方法:50例飞行员分为实验组和对照组,实验组服脂肪负荷餐,对照组未服,于空腹,餐后3、8h分别采血,测定血浆甘油三酯(TG),总胆固醇(CHO)、高密度脂蛋白-胆固醇(HDL-C),载脂蛋白(Apo)A1,B和纤维蛋白原(FIB)水平,结果:实验组TRL清除延迟发生率4/25,组无TRL清除延迟,两组相比差异有显著性意义(P<0.01),餐后高TG应答与血浆HDL-C水平降低呈负相关(P<0.01),餐后3h ApoA1,CHO降低;ApoB,FIB升高,餐后8h HDL0C,CHO,ApoB,FIB仍未恢复至空腹水平,与空腹相比差异有显著性意义(P<0.01),结论:飞行员TRL清除延迟可以作为IV型高脂蛋白血症的判断指标,它与膳食脂肪摄入量过高有关,餐后TRL清除延迟可导致高TG/低HLD-C综合征,血浆ApoA1降低,ApoB升高代谢异常,导致血液高凝状态,上述现象构成了动脉粥样硬化形成和发展的综合危险因素。 相似文献
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Poirier P Mawhinney S Grondin L Tremblay A Broderick T Cléroux J Catellier C Tancrède G Nadeau A 《Medicine and science in sports and exercise》2001,33(8):1259-1264
PURPOSE: To compare the changes in plasma glucose and insulin levels in response to 1 h of exercise performed at 60% of VO(2peak) either in the fasted state or 2 h after a standardized breakfast in subjects with type 2 diabetes. METHODS: Ten sedentary men with type 2 diabetes treated with oral agents and not under strict metabolic control were tested on two occasions (fasted and fed state) in a random order at a 1-wk interval. RESULTS: Plasma glucose was slightly but not significantly higher at the beginning of exercise performed in the fed state versus the fasted state (12.4 +/- 1.3 vs 11.1 +/- 1.1 mmol x L(-1) respectively; mean +/- SE, P = 0.06). However, after exercise, plasma glucose levels were much lower in the fed state (7.6 +/- 1.1 mmol x L(-1)) compared with the fasted state (10.0 +/- 1.0 mmol x L(-1); P = 0.009). Insulin levels were higher at the beginning of the exercise bout performed in the fed state (177 +/- 26 vs 108 +/- 19 pmol x L(-1); P < 0.05) and during exercise. Similar respiratory exchange ratio at identical workload indicated that the difference in glycemic response was not due to differences in whole body substrate utilization. Plasma concentrations of free fatty acids, glucagon, epinephrine, and norepinephrine were also similar during both experiments. CONCLUSIONS: One hour of aerobic exercise has a minimal impact on plasma glucose level when performed in fasted moderately hyperglycemic men with type 2 diabetes but induces an important decrease in plasma glucose level when performed 2 h after breakfast. Because glucose utilization increased similarly during exercise in both conditions, the higher insulin levels after the meal might have blunted glucose production, creating an imbalance between total glucose production and total peripheral utilization in the fed state in contrast to the fasted state. 相似文献
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目的比较诺和锐30和诺和灵30R治疗在开始胰岛素治疗的2型糖尿病(T2DM)患者的疗效和安全性。方法将60例T2DM患者随机分为诺和锐30治疗组和诺和灵30R治疗组,采用每日早、晚餐前皮下注射方案,为期12周。观察两组患者不同时点血糖、糖化血红蛋白(HbA1c)、低血糖事件及其他不良事件的差异。结果诺和锐30治疗组三餐后血糖水平、低血糖发生次数明显低于诺和灵30R治疗组(P〈0.05);两组HbA1c、胰岛素用量及其他不良事件差异无统计学意义。结论T2DM患者采用诺和锐30治疗时,对餐后血糖控制更为满意,且低血糖事件发生率少。 相似文献
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目的:探讨心理干预对Ⅱ型糖尿病患者临床疗效和自尊水平的影响。方法:选择60例Ⅱ型糖尿病患者,采用随机数字表法,将患者随机分为观察组和对照组,每组30例。对照组采用糖尿病常规护理模式,观察组应用心理干预护理措施,观察两组护理后的临床疗效(空腹血糖、餐后2h血糖、体重指数)和自尊水平(Rosenberg自尊量表)。结果:护理前两组空腹血糖、餐后2h血糖、体重指数无统计学差异,P〉0.05,护理后,观察组的空腹血糖、餐后2h血糖明显低于对照组,P〈0.05,体重指数比对照组低,但无统计学意义,P〉0.05。护理前两组Rosenberg自尊量表评分无显著性差异,P〉0.05,护理后,观察组Rosenberg自尊量表评分明显高于对照组,P〈0.05。结论:心理干预能有效改善Ⅱ型糖尿病患者的临床疗效,提高自尊水平。 相似文献
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Dubé MC Weisnagel SJ Prud'homme D Lavoie C 《Medicine and science in sports and exercise》2005,37(8):1276-1282
PURPOSE: To determine the glucose supplement required to prevent hypoglycemia during moderate-intensity exercise in Type 1 diabetic patients using newer analog insulins. METHODS: Nine subjects performed 60 min of ergocycle exercise (50% VO2max), 3 h after a standard breakfast in three different conditions. Subjects were randomly assigned to preexercise liquid glucose supplement of 0 g of glucose (0G), 15 g of glucose (15G), and 30 g of glucose (30G). Blood glucose (BG) was measured before, during, and following the exercise. All subjects used Humulin N (N) and analog insulin Humalog (Lispro). A dextrose infusion was initiated when BG fell below 5 mmol x L(-1). RESULTS: There was no significant difference in the magnitude of the decrease in BG exercise-induced when comparing the three experimental conditions. However, the quantity of dextrose infused was significantly higher in the 0G (10.5 +/- 3.2 g) than in the 15G (3.5 +/- 1.8 g) or the 30G conditions (1.6 +/- 1.0 g). The addition of a glucose supplement (15G or 30G) significantly prolonged the delay before the need for dextrose infusion (31.7 +/- 7.5, 51.3 +/- 4.2, and 55.6 +/- 2.6 min; 0G, 15G, and 30G, respectively). The quantity of dextrose infusion was plotted against the three preexercise glucose supplements and a regression equation obtained. Solving this equation, a glucose supplement of 40 g was estimated in order to maintain BG levels within the normal range during and after exercise. CONCLUSION: For 60 min of late postprandial exercise followed by 60 min of recovery, an estimated 40 g of a liquid glucose supplement, ingested 15 min prior exercise, would seem likely to help maintain safe BG levels in subjects using N-Lispro. 相似文献
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PURPOSE: The purpose of this study was to examine the effect of high and low glycemic index (GI) carbohydrate (CHO) pre-exercise meals on endurance running capacity. METHODS: Eight active subjects (five male and three female) ran on a treadmill at approximately 70% VO2max to exhaustion on two occasions separated by 7 d. Three hours before the run after an overnight fast, each subject was given in a single-blind, random order, isoenergetic meal of 850+/-21 kcal (mean+/-SEM; 67% carbohydrate, 30% protein, and 3% fat) containing either high (HGI) or low (LGI) GI carbohydrate foods providing 2.0 g CHO.kg(-1) body weight. RESULTS: Ingestion of the HGI meal resulted in a 580% and 330% greater incremental area under the 3-h blood glucose and serum insulin response curves, respectively. Performance times were not different between the HGI and LGI trials (113+/-4 min and 111+/-5 min, respectively). During the first 80 min of exercise in the LGI trial, CHO oxidation was 12% lower and fat oxidation was 118% higher than in the HGI trial. Although serum insulin concentrations did not differ between trials, blood glucose at 20 min into exercise in the HGI trial was lower than that during the LGI trial at the same time (3.6+/-0.3 mmol.L(-1) vs 4.3+/-0.3 mmol.L(-1); P < 0.05). During exercise, plasma glycerol and serum free fatty acid concentrations were lower in the HGI trial than in the LGI trial. CONCLUSIONS: This results demonstrate that although there is a relative shift in substrate utilization from CHO to fat when a low GI meal is ingested before exercise compared with that for a high GI meal, there is no difference in endurance running capacity. 相似文献
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目的 寻找积极有效的糖尿病饮食教育方式,提高糖尿病患者接受饮食教育的效果.方法 将160例2型糖尿病患者随机分为试验组和对照组,试验组应用食物模具对患者进行饮食教育,对照组则采用传统教育方式进行教育.结果 两组患者的空腹血糖、餐后2 h血糖、糖化血红蛋白均有不同程度的降低,两组比较试验组优于对照组(P<0.01).结论... 相似文献
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The purpose of this study was to investigate the effects of glucose ingestion (GI) at different time periods prior to exercise on blood glucose (BG) levels during prolonged treadmill running. Eight subjects (X+/-SD), age 20+/-0.5yr, bodymass 70.7+/-4.1 kg, height 177+/-4 cm, VO2max 52.8+/-7.8 ml x kg(-1) x min(-1) who underwent different experimental conditions ingested a glucose solution (1 g/kg at 350 ml) 30 min (gl-30), 60 min (gl-60), 90 min (gl-90), and a placebo one 60 min (pl-60) prior to exercise in a counterbalanced design. Afterwards they ran at 65% of VO2max for 1 hour and then at 75 % of VO2max till exhaustion. Fingertip blood samples (10 microl) were drawn every 15 min before and during exercise for the determination of BG levels. Oxygen uptake (VO2), heart rate (HR), and blood lactate (La) were also measured every 15 min during exercise. Peak BG values were reached within 30 min after GI but were different (p < 0.01) at the onset of exercise (gl-30: 147+/-22, gl-60: 118+/-25, gl-90: 109+/-22, pl-60: 79+/-5mg/dl). The two-way ANOVA repeated measures and the Tukey post-hoc test revealed a higher BG concentration (p < 0.05) for the gl-30 and the pl-60 as compared to the gl-60 and gl-90 during running (e.g. 15min run: 82+/-11, 68+/-5, 64+/-3, 78+/-7, and 60min run: 98+/-12, 85+/-12, 83+/-11, 94+/-11 mg/dl for gl-30, gl-60, gl-90, and pl-60, respectively). However, this did not significantly affect the duration of treadmill running. The La levels were higher (p < 0.05) after GI as compared to placebo throughout exercise (values at exhaustion: 4.6+/-0.2, 5.0+/-1.5, 4.8+/- 1.7 mmol/l for gl-30, gl-60, gl-90, and 3.5+/-0.8 mmol/l for placebo). The gl-30 and the placebo fluctuated closer to normoglycaemic levels. The glucose ingestion (60 to 90 min) prior to exercise lowered the blood glucose levels without affecting the duration of running performance at 75% VO2max. Thus, in order to maintain normoglycaemic levels, pre-exercise glucose supplementation should be given 30 min before the onset of exercise. 相似文献
18.
目的 探讨高原高寒环境下肢体枪弹伤后机体糖、蛋白质、脂肪代谢的变化特点.方法 将24只小型猪随机分为高原战时组(GZ)、高原平时组(GP)和平原平时组(PP),分别于伤前、伤后30 min、2 h、6 h、12 h、1 d、2 d、3 d、5 d、7 d、10 d、14 d采静脉血,测定血糖、乳酸、游离脂肪酸和总氨基酸.同时于伤前、伤后7 d和14 d称量动物的体重.结果 (1)伤后30 min,PP组、GP组、GZ组的血糖分别为伤前的142%、156%和179%,PP组、GP组分别于伤后1 d和3 d时与伤前无显著差异,而GZ组直到伤后14 d仍显著高于伤前水平.(2)伤后30 min,PP组、GP组、GZ组的血乳酸分别为伤前的203%、204%和233%,3组分别于伤后1 d、2 d和3 d时与伤前无显著差异.(3)伤后6 h及2 h,PP组和GP组血游离脂肪酸分别降至最低点,分别为伤前值的71.3%和33.9%,均于伤后2 d恢复至伤前值,至7 d时达高峰,分别为伤前的138%和177%.而GZ组伤前就是GP组的267%,伤后2 h为伤前的51.9%,此后逐渐升高,至1 d后稳定在伤前的84%上下,始终高于GP和PP两组.(4)伤后3组总氨基酸早期升高幅度依次为GZ〉GP〉PP,PP组伤后12 h时、GP组伤后7 d时与伤前无统计学差异,GZ组伤后14 d仍高于GP组.(5)伤后动物生长速度依次为GZ〈GP〈PP.结论 高原战时枪弹伤后,机体糖代谢呈现高分解高酵解的特点,脂肪代谢呈现高分解高消耗的特点,蛋白质代谢呈现高分解低合成的特点,强度和持续时间依次为GZ〉GP〉PP. 相似文献
19.
Mitchell JB Braun WA Pizza FX Forrest M 《The Journal of sports medicine and physical fitness》2000,40(1):41-50
BACKGROUND: The purpose of this study was to determine the influence of ingesting solutions containing mixtures of carbohydrate (CHO) types on pre-exercise glycemic response, exercise-induced hypoglycemia, metabolic responses, and 10-km treadmill running performance in a warm environment. METHODS: Ten trained runners completed 6, self-paced 10-km treadmill runs one hour after ingesting 900 ml of one of the following test solutions: a water placebo (WP), an 8 g 100 ml-1 high fructose corn syrup solution (HFG; 72 g CHO), a 6 g 100 ml-1 glucose solution (GLU; 54 g CHO), a 6 g.100 ml-1 sucrose/glucose mixture (SUG; 54 g CHO), or banana with water to equal 900 ml (BAN; approx. 54 g CHO). The sixth condition was 675 ml of an 8 g.100 ml-1 HFCS solution (LFG; 54 g CHO). Blood samples were taken prior to ingestion and every 15 min during rest and at 15 and 30 min, and at the end of the 10-km run. Blood was analyzed for glucose (BG) insulin (IN), glycerol, lactate, and percent change in plasma volume. Urine volume during the 1 hour of rest and change in body mass during exercise were also determined. RESULTS: A significant (p < 0.05) correlation (r = -0.684) was seen between the pre-exercise glycemic response (PEGR = area under the resting BG curve) and the change in BG from pre-EX to 15 min of exercise. BG at 15 min of exercise was significantly higher in the WP (5.22 mM) versus the other conditions (HFG = 3.32, LFG = 3.91, GLU = 3.38, BAN = 3.74 & SUG = 3.63 mM). Pre-exercise IN was lower in the WP (6.54 U ml-1) condition versus the other conditions (HFG = 22.1, LFG = 16.2, GLU = 23.3, BAN = 18.8 & SUG = 12.8 U.ml-1). Ten km performance times were not different (WP = 41.87, HFG = 41.66, LFG = 41.79, GLU = 41.65, BAN = 41.53, and SUG = 41.75 min). A significantly greater body mass loss occurred due to urine production during the 60 min of rest in the WP compared to the other conditions. The degree of exercise-induced decline in blood glucose was related to the PEGR; however, the decline in BG did not affect 10-km running performance. In addition, there were no differences in the metabolic responses during exercise between the different CHO types, nor did the type of CHO influence running performance. Finally, the presence of CHO and/or electrolytes in the hydration solutions produced a better fluid retention during the 60-min pre-exercise rest period compared to water. CONCLUSIONS: The results confirmed that if a competitive athlete consumed a breakfast prior to ingesting a CHO-electrolyte beverage, a practice that is common, the glycemic responses may be different. 相似文献