Advanced Research Initiative for Human High Performance (ARIHHP); Faculty of Health and Sport Sciences, University of Tsukuba, Tsukuba, Japan.
Faculty of Health and Sport Sciences, University of Tsukuba, Tsukuba, Japan.
Physiol Behav. 2022 Oct 15;255:113942. doi: 10.1016/j.physbeh.2022.113942. Epub 2022 Aug 12.
Sugar-free carbonated water is consumed worldwide. The consumption of carbonated water is high in summer, when the heat loss responses of sweating and skin vasodilation are activated, and thermal perceptions (thermal sensation and comfort) and mood states are negatively modulated. However, whether ingesting carbonated water under ambient heat exposure modulates cerebral blood flow index, heat loss responses, thermal perceptions, and mood states remains to be determined. In this study, 17 healthy, habitually active, young adults (eight women) ingested 4 °C noncarbonated or carbonated water under 37 °C ambient heat-stressed resting conditions. Both drinks increased the middle cerebral artery mean blood velocity, an index of cerebral blood flow, and mean arterial pressure, with carbonated water exhibiting higher elevations than noncarbonated water (P < 0.05). However, the heart rate, sweat rate, and skin blood flow during and after drinking remained unchanged between the two conditions (P > 0.05). The thermal sensation and comfort after drinking remained unchanged between the two conditions (P > 0.05); but, a drink-induced reduction in sleepiness was higher, and drink-induced elevations in motivation and exhilaration were higher after ingesting carbonated water than those after ingesting noncarbonated water (P < 0.05). The analyses suggest that in humans under ambient heat-stressed resting conditions, ingestion of cold carbonated water increases the cerebral blood flow index, blood pressure, motivation, and exhilaration, whereas it decreases sleepiness relative to ingestion of noncarbonated cold water. However, ingestion of cold carbonated water fails to modulate thermoregulatory responses and thermal perception as opposed to noncarbonated cold water.
无糖碳酸水在全球范围内都有消费。碳酸水的消费在夏季较高，此时出汗和皮肤血管扩张的热损失反应被激活，热感觉（热感觉和舒适度）和情绪状态受到负面影响。然而，在环境热暴露下饮用碳酸水是否会调节脑血流指数、热损失反应、热感觉和情绪状态仍有待确定。在这项研究中，17 名健康、习惯活跃的年轻成年人（8 名女性）在 37°C 的环境热应激休息条件下饮用 4°C 的非碳酸或碳酸水。两种饮料均增加了大脑中动脉平均血流速度，即脑血流指数，以及平均动脉压，碳酸水的升高幅度高于非碳酸水（P<0.05）。然而，在饮用过程中和饮用后，心率、出汗率和皮肤血流量在两种条件之间保持不变（P>0.05）。两种条件下的热感觉和舒适度在饮用后保持不变（P>0.05）；但是，饮用碳酸水后引起的困倦感降低程度更高，饮用碳酸水后引起的动机和兴奋感升高程度高于饮用非碳酸水后（P<0.05）。分析表明，在环境热应激休息条件下的人体中，饮用冷碳酸水会增加脑血流指数、血压、动机和兴奋感，而与饮用非碳酸冷水相比，会降低困倦感。然而，与非碳酸冷水相比，饮用冷碳酸水并不能调节体温调节反应和热感觉。
