Department of Human Services, University of Virginia, Charlottesville, VA 22904, USA.
Med Sci Sports Exerc. 2009 Jun;41(6):1326-33. doi: 10.1249/MSS.0b013e3181967637.
To examine the effects of carbohydrate (CHO) ingestion on the RPE-blood lactate relationship during incremental and constant-effort exercise.
Six male and three female subjects (mean age = 27.2 +/- 8.2 yr, height [ht] = 174.5 +/- 13.5 cm, weight [wt] = 68.9 +/- 12.5 kg, body fat = 18.5 +/- 8.3%), completed two incremental cycling lactate threshold (LT)/(.)VO2peak tests followed by two 45-min production trials. Two hundred and forty milliliters of either carbohydrate or placebo (PL) was ingested before and every 15 min during exercise.
No differences were observed between conditions at LT, 2.5 and 4.0 mM, and peak. Within the CHO condition: V O2 = 25.0, 32.6, 37.5, 47.2 mL x kg x min(-1); power output = 123.3, 170.7, 200.1, 241.7 W; RPE = 12.8, 15.4, 17.2, 19.3; and HR = 137.4, 156.8, 168.7, 187.7 beats x min(-1) at LT, 2.5 mM, 4.0 mM, and peak, respectively. Within PL: V O2 = 24.7, 32.5, 36.8, 45.7 mL x kg x min(-1); power output = 130.0, 175.4, 201.9, 240.0 W; RPE = 12.1, 15.0, 17.0, 19.3; and HR = 134.9, 157.9, 169.6, 187.2 beats x min(-1), respectively. In the CHO condition, blood glucose was higher (P < 0.001), and a trend was observed for lower RPE over time (P = 0.07). During the production trials (RPE of 16) in the CHO condition, higher blood glucose area under the curve (AUC) (PL: 204.1 +/- 79.3 mM; CHO: 220.6 +/- 18.5 mM; P = 0.039) and a trend for greater total work (PL: 448.5 +/- 73.8 kJ; CHO: 470.5 +/- 65.6 kJ; P = 0.089) were observed.
We conclude that 1) CHO ingestion does not alter the blood lactate-RPE relationship during incremental LT/(.)VO2peak cycling; and 2) carbohydrate supplementation during exercise, eliciting high RPE, may increase work output during training sessions.
研究递增和恒力运动过程中碳水化合物（CHO）摄入对 RPE-血乳酸关系的影响。
6 名男性和 3 名女性受试者（平均年龄=27.2±8.2 岁，身高[ht]=174.5±13.5cm，体重[wt]=68.9±12.5kg，体脂=18.5±8.3%）完成了两次递增的乳酸阈（LT）/（.）VO2peak 测试，然后进行了两次 45 分钟的做功试验。在运动前和运动每 15 分钟摄入 240 毫升 CHO 或安慰剂（PL）。
在 LT、2.5 和 4.0 mM 以及峰值时，两种条件之间没有观察到差异。在 CHO 条件下：V O2=25.0、32.6、37.5、47.2 mL x kg x min(-1)；功率输出=123.3、170.7、200.1、241.7 W；RPE=12.8、15.4、17.2、19.3；HR=137.4、156.8、168.7、187.7 次 x min(-1)，分别在 LT、2.5 mM、4.0 mM 和峰值时。在 PL 中：V O2=24.7、32.5、36.8、45.7 mL x kg x min(-1)；功率输出=130.0、175.4、201.9、240.0 W；RPE=12.1、15.0、17.0、19.3；HR=134.9、157.9、169.6、187.2 次 x min(-1)，分别在 PL 中。在 CHO 条件下，血糖升高（P<0.001），且 RPE 随时间呈下降趋势（P=0.07）。在 CHO 条件下的做功试验（RPE 为 16）中，血糖 AUC（PL：204.1±79.3mM；CHO：220.6±18.5mM；P=0.039）和总工作量的趋势（PL：448.5±73.8kJ；CHO：470.5±65.6kJ；P=0.089）较高。
我们得出结论：1）CHO 摄入不会改变递增 LT/（.）VO2peak 自行车运动中的血乳酸-RPE 关系；2）运动时补充碳水化合物，产生较高的 RPE，可能会增加训练期间的工作量。
