Sports Performance Laboratory, Department of Kinesiology & Sport Management, Texas Tech University, Lubbock, TX 79409, USA.
Applied Physiology Laboratory, Department of Kinesiology & Sport Management, Texas Tech University, Lubbock, TX 79409, USA.
Nutrients. 2024 Sep 23;16(18):3212. doi: 10.3390/nu16183212.
To investigate the effects of thirst on later hydration status, total water intake (TWI-MA), and its potential sex differences. Twelve men (mean ± standard deviation; age: 21 ± 2 years; mass: 81.0 ± 15.9 kg) and twelve women (age: 22 ± 3 years; mass: 68.8 ± 15.2 kg) visited the laboratory in the morning (first thing in the morning) and afternoon (2:00-4:00 p.m.) for three consecutive days under a free-living condition. At each visit, urine osmolality (U), urine specific gravity (USG), urine color (U), body mass loss (BML), thirst, and plasma osmolality (P) were collected and analyzed. The participants recorded their food and fluid intake between the visits to determine TWI-MA. Linear regression was used to predict the effect of morning thirst on the afternoon hydration indices for all the participants, as well as for males and females separately. Higher morning thirst predicted lower U (r = 0.056, = 0.045), USG (r = 0.096, = 0.008), U (r = 0.074, = 0.021), and higher thirst (r = 0.074, = 0.021) in the afternoon. However, morning thirst did not predict afternoon BML, P, or TWI-MA ( > 0.05). In males, higher morning thirst predicted lower afternoon U (r = 0.130, = 0.031) and USG (r = 0.153, = 0.018). Additionally, higher morning thirst predicted higher TWI-MA (r = 0.154, = 0.018) in females. Morning thirst had a negligible impact on later hydration status, specifically with afternoon urine indices. Furthermore, higher thirst sensation did not impact BML, P, or TWI-MA. However, thirst sensation minimally contributed to drinking behavior in females. Overall, individuals may not rely solely on thirst sensation to manipulate their drinking behavior to optimize their fluid balance during their daily lives due to the complexity of thirst mechanisms.
为了探究口渴对后续水合状态、总水摄入量（MA 期）及其潜在性别差异的影响，12 名男性（平均值±标准差；年龄：21±2 岁；体重：81.0±15.9kg）和 12 名女性（年龄：22±3 岁；体重：68.8±15.2kg）在连续 3 天的自由生活条件下，分别于早上（上午第一件事）和下午（下午 2:00-4:00）到实验室进行访问。每次访问时，收集并分析尿液渗透压（U）、尿比重（USG）、尿色（U）、体重损失（BML）、口渴和血浆渗透压（P）。参与者记录访问之间的食物和液体摄入量，以确定 MA 期的总水摄入量。线性回归用于预测所有参与者以及男性和女性的早上口渴对下午水合指数的影响。较高的早上口渴预测较低的下午 U（r=0.056， =0.045）、USG（r=0.096， =0.008）、U（r=0.074， =0.021）和较高的口渴（r=0.074， =0.021）。然而，早上口渴并没有预测下午 BML、P 或 TWI-MA（>0.05）。在男性中，较高的早上口渴预测较低的下午 U（r=0.130， =0.031）和 USG（r=0.153， =0.018）。此外，较高的早上口渴预测女性更高的 TWI-MA（r=0.154， =0.018）。早上口渴对后续水合状态的影响可以忽略不计，特别是对下午的尿指数。此外，较高的口渴感不会影响 BML、P 或 TWI-MA。然而，口渴感在女性的饮酒行为中仅略有贡献。总体而言，由于口渴机制的复杂性，个体可能不会仅仅依靠口渴感来操纵他们的饮酒行为，以在日常生活中优化他们的液体平衡。
