Summary: Esports athletes often turn to sugary energy drinks or caffeine to survive grueling three-hour sessions, but a healthier alternative may be sitting right in the fridge. A research team has discovered that drinking unsweetened, highly carbonated water helps players maintain mental focus, reduce cognitive fatigue, and enjoy the game more compared to drinking plain water.
The study suggests that the physical sensation of carbonation may engage specific brain pathways that keep the prefrontal cortex sharp during prolonged mental strain.
Key Facts
- Cognitive Maintenance: Players drinking sparkling water showed significantly better performance on executive function tests (flanker tasks) than those drinking plain water.
- The “Throat Hit” Connection: Researchers believe the physical sensation of carbonation in the throat may stimulate brainstem-to-prefrontal pathways linked to executive control and attention.
- Fatigue Dampening: Sparkling water reduced subjective feelings of exhaustion and prevented “pupil constriction,” a physiological marker of cognitive fatigue.
- Fair Play Boost: Interestingly, players drinking carbonated water committed fewer fouls during virtual soccer matches, suggesting better inhibitory control.
- Healthier Alternative: The benefits were achieved without the need for glucose or caffeine, which are linked to long-term risks like obesity and diabetes.
Source: University of Tsukuba
A University of Tsukuba research team has found that drinking unsweetened, highly carbonated (sparkling) water during a three-hour esports session can help players maintain mental focus with less fatigue and greater game enjoyment than when drinking plain water.
The study is published in the journal Computers in Human Behavior Reports.
Extended esports play can lead to mental fatigue, resulting in slower and less precise decision-making (diminished executive control) and a variety of physiological responses indicative of impaired sensorimotor or cognitive function. In such cases, many players reach for caffeinated or sugary drinks, but overconsumption raises health concerns such as elevated risks of obesity and diabetes.
Sparkling water offers a healthier alternative, as it contains no sugar or caffeine, yet produces a similar sensation in the throat that may engage brainstem-to-prefrontal pathways linked to executive control.
In a randomized crossover study, 14 young adults played virtual soccer for three hours on two separate occasions while drinking either sparkling water or plain water.
Researchers continuously tracked pupil diameter and heart rate, assessed subjective fatigue and game enjoyment hourly, tested executive function using a flanker task (in which participants must decide if stimuli flanking a central stimulus are congruent or incongruent—such as arrows pointing in the same or opposite direction), and periodically measured interstitial glucose and salivary cortisol.
Compared with plain water, sparkling water dampened subjective fatigue, boosted enjoyment, improved executive function test performance, and reduced pupil constriction. Greater pupil constriction was also associated with slower flanker-task responses, supporting pupil diameter as an easily measurable sign of cognitive fatigue.
In contrast, heart rate, interstitial glucose, and cortisol were comparable across conditions. Players drinking sparkling water also committed fewer fouls, while there were no significant changes in offensive or defensive performance metrics.
These results support sparkling water consumption as an effective way to maintain mental focus during prolonged esports play without sugar or caffeine intake.
Key Questions Answered:
A: If your goal is focus and endurance without the “crash,” yes. The study shows it keeps your brain’s “executive control” active. You won’t get the caffeine jolt, but you’ll stay precise and commit fewer errors (and fouls) in the long run.
A: Sensory inputs from the mouth and throat are processed by the brainstem, which has direct connections to the prefrontal cortex—the part of the brain responsible for decision-making. The “sparkle” acts as a gentle, constant stimulant for these pathways.
A: The study used unsweetened, highly carbonated water. The key is the level of carbonation; that intense “fizz” is what provides the sensory stimulation needed to keep fatigue at bay.
Editorial Notes:
- This article was edited by a Neuroscience News editor.
- Journal paper reviewed in full.
- Additional context added by our staff.
About this neuroscience, gaming, and focus research news
Author: Press Office
Source: University of Tsukuba
Contact: Press Office – University of Tsukuba
Image: The image is credited to Neuroscience News
Original Research: Open access.
“Sparkling water consumption mitigates cognitive fatigue during prolonged esports play” by Shion Takahashi, Wataru Kosugi, Seiichi Mizuno, and Takashi Matsui. Computers in Human Behavior Reports
DOI:10.1016/j.chbr.2026.100943
Abstract
Sparkling water consumption mitigates cognitive fatigue during prolonged esports play
Prolonged esports play induces cognitive fatigue, characterized by diminished executive function with pupil constriction. Players often rely on caffeinated or sugary drinks to combat fatigue, but regular use poses health risks.
Sparkling water, a sugar- and caffeine-free beverage, stimulates brainstem and prefrontal activity via sensory pathways potentially mediated by transient receptor potential (TRP) channels in the throat.
This study tested the hypothesis that sparkling water mitigates cognitive fatigue during prolonged esports play.
Fifteen young adult players participated in a randomized crossover trial, each completing two 3-h sessions of a virtual football game while consuming either sparkling water or plain water. Subjective fatigue, enjoyment, and executive function (via a flanker task) were measured at baseline and hourly, while pupil diameter and heart rate were monitored continuously.
Blood glucose and salivary cortisol were assessed periodically. Compared to plain water, sparkling water significantly attenuated increases in subjective fatigue, enhanced enjoyment, and preserved executive function, along with preventing pupil constriction. Heart rate, blood glucose, and salivary cortisol levels did not differ between conditions.
Notably, players committed fewer in-game fouls with sparkling water, while offensive and defensive performance remained unchanged.
These findings demonstrate that sparkling water contribute to alleviate both subjective and objective signs of cognitive fatigue during prolonged esports play, consistent with our hypothesis.
This non-caffeinated intervention may help sustain inhibitory control and promote fair behavior, offering a safe and sustainable strategy for managing mental fatigue in modern life.
