Pires Flávio O, Pinheiro Fabiano A, Brietzke Cayque, Franco-Alvarenga Paulo Estevão, Veras Katherine, de Matos Eugênia C T, Rodacki André L F, Ugrinowitsch Carlos
Exercise Psychophysiology Research Group, School of Arts, Science and Humanities, University of São Paulo, São Paulo, Brazil.
School of Physical Education and Sports, University of São Paulo, São Paulo, Brazil.
Front Nutr. 2024 Feb 20;11:1329074. doi: 10.3389/fnut.2024.1329074. eCollection 2024.
We examined if carbohydrate (CHO) mouth rinse may reduce central fatigue and perceived exertion, thus improving maximal incremental test (MIT) performance. Nine recreational cyclists warmed up for 6 min before rinsing a carbohydrate (CHO) or placebo (PLA) solution in their mouth for 10 s in a double-blind, counterbalanced manner. Thereafter, they performed the MIT (25 W·min increases until exhaustion) while cardiopulmonary and ratings of perceived exertion (RPE) responses were obtained. Pre- to post-MIT alterations in voluntary activation (VA) and peak twitch torque (Tw) were determined. Time-to-exhaustion ( = 0.24), peak power output (PPO; = 0.45), and V̇O ( = 0.60) were comparable between conditions. Neither treatment main effect nor time-treatment interaction effect were observed in the first and second ventilatory threshold when expressed as absolute or relative V̇O ( = 0.78 and = 0.96, respectively) and power output ( = 0.28 and = 0.45, respectively) values, although with moderate-to-large effect sizes. RPE increased similarly throughout the tests and was comparable at the ventilatory thresholds ( = 0.56). Despite the time main effect revealing an MIT-induced central and peripheral fatigue as indicated by the reduced VA and Tw, CHO mouth rinse was ineffective in attenuating both fatigues. Hence, rinsing the mouth with CHO was ineffective in reducing central fatigue, lowering RPE, and improving MIT performance expressed as PPO and time-to-exhaustion. However, moderate-to-large effect sizes in power output values at VT and VT may suggest some beneficial CHO mouth rinse effects on these MIT outcomes.
我们研究了碳水化合物（CHO）漱口是否可以减轻中枢疲劳和主观用力感觉，从而改善最大递增测试（MIT）表现。九名休闲自行车运动员在进行6分钟热身运动后，以双盲、平衡的方式在口中含漱碳水化合物（CHO）或安慰剂（PLA）溶液10秒。此后，他们进行MIT（以25W·min的增量递增直至力竭），同时获取心肺指标和主观用力感觉（RPE）反应。测定MIT前后的自愿激活（VA）和峰值抽搐扭矩（Tw）变化。力竭时间（=0.24）、峰值功率输出（PPO；=0.45）和摄氧量（V̇O；=0.60）在不同条件下具有可比性。当以绝对或相对V̇O（分别为=0.78和=0.96）以及功率输出（分别为=0.28和=0.45）值表示时，在第一和第二通气阈值中未观察到处理主效应或时间-处理交互效应，尽管效应大小为中等至较大。在整个测试过程中，RPE的增加情况相似，并且在通气阈值时具有可比性（=0.56）。尽管时间主效应显示，如VA和Tw降低所示，MIT会引起中枢和外周疲劳，但CHO漱口在减轻这两种疲劳方面均无效。因此，用CHO漱口在减轻中枢疲劳、降低RPE以及改善以PPO和力竭时间表示的MIT表现方面均无效。然而，在VT和VT时功率输出值的中等至较大效应大小可能表明CHO漱口对这些MIT结果有一些有益影响。
