Caffeine boosts eSports performance: Enhanced reaction and shooting skills in pro gamers

By Hugo Francisco de SouzaJan 25 2024Reviewed by Susha Cheriyedath, M.Sc.

In a recent study published in the journal Scientific Reports, researchers investigated the impacts of caffeine supplementation on the first-person shooter (FPS) performance of trained professional eSports players. They used a two-arm crossover, randomized, controlled methodology to evaluate the effects of 3 mg/kg of caffeine (cases) on participants' cognitive and shooting performance compared to their placebo-supplemented cohorts (controls). Study findings reveal that caffeine supplementation significantly improved reaction times, visual search reaction time, and shooting performance (kill ratio and accuracy) in cases compared to the controls. This highlights that 3 mg/kg of caffeine, ingested before (1 hour) competitive gaming, could enhance performance during the game.

Study: Caffeine supplementation improves the cognitive abilities and shooting performance of elite e-sports players: a crossover trial. Image Credit: aslysun / Shutterstock

What are eSports, and why the competition?

Electronic sports, 'eSports' in short, is a form of competitive spectator sport using video games. The industry has been gaining popularity in recent decades, with the eSports market size valued at USD 1.72 billion in 2023. This popularity has resulted in the field being recognized by numerous nationalities as a formal sport. Its inclusion in the 2018 Asian Games (Jakarta) as a demonstration event and as an official sport in the 2023 Sian Games (Hangzhou) has further fed into the feedback loop, driving eSports' rise to prominence. Current estimates predict the industry's market share to grow to 6.8 billion by the end of the current decade.

"E-sports include multiplayer online battlefield arena games (e.g., League of Legends), first-person shooter games (e.g., Counter-Strike: Global Offensive, and Valorant), real-time strategy games, and sports games. For example, Game for Peace is a first-person shooting game and an official sport of the 2023 Hangzhou Asian Games."

Research on trained eSports professionals has revealed that these players present improved Stroop test scores (reaction time) and visual search abilities than their casual gamer counterparts, suggesting a link between cognition and eSports success and, in turn, a place for natural external supplements aimed at enhancing cognitive abilities. A notable candidate for the supplement role is caffeine. Used by athletes of all disciplines and at all levels, caffeine is an effective ergogenic supplementation that elicits effect by dampening the impact of endogenous adenosine, thereby improving mood, energy levels, fatigue, and potentially cognition.

While previous literature exploring the eSports performance gains of caffeine supplementation does exist, tests on fast-paced first-person shooters (FPSs) are limited to one study, which only tested reaction time, with shooting performance and visual search reaction time data lacking. Given that caffeine is medically recommended for consumption at safe doses of 3-6 mg/kg, establishing the performance gains of small caffeine doses could provide all gamers a slight competitive advantage.

About the study

In the present work, researchers recruited nine male professional eSports athletes (mean age 20.8 years) to participate in a single-blind, crossover study to investigate the efficacy of 3 mg/kg of caffeine ingested one hour before gaming on shooting and cognitive performance during gameplay. The study was conducted between 01/01/2022 and 30/04/2022 and included three familiarization tests common to all participants.

Study inclusion criteria comprised sex (male), age (above 20 years), and the lack of pain, insomnia, and recent injuries. Females were excluded from the study due to concerns that their menstrual cycle may alter quantifiable results. Included participants were randomly assigned to the case (3 mg/kg of caffeine, one hour before gaming) and control (placebo) cohorts and were instructed to restrict their daily caffeine intake from all sources to 80 mg, both for the duration of the study, and the two weeks prior.

The experimental protocol involved the consumption of a capsule of treatment (caffeine or placebo) along with 200 mL of water, followed by one hour of rest before beginning their regular gaming session. Reaction and search times were measured using the color-word Stroop task and visual search test, respectively. Finally, a three-dimensional aim trainer assessed shooting accuracy and kill performance.

"In each round, three targets appeared at once, and participants were required to shoot them within 2 s, ideally eliminating each target with a one-shot kill. Participants' kill ratio (number of targets hit/60), hit accuracy (60/number of shooting), and average time to target were noted."

Statistical analyses included the Shapiro-Wilk test to assess data normality, the paired sample t-test to compare results between cases and controls, and Choen's D for computing effect sizes.

Study findings

Stroop task results reveal significantly shorter reaction times in the caffeine cohort compared to their placebo-ingesting counterparts. Visual search time analysis reveals similar results, with cases far outperforming controls in the time taken to identify 20 items.

Kill ratio, accuracy, and average time to target were significantly improved (P = 0.020, 0.008, 0.001, respectively) after caffeine ingestion. These findings highlight the use of caffeine in competitive eSports settings and form the basis for future research into means of further cognitive performance gain (caffeine without water, for example).

"A dosage of 3 mg/kg of caffeine supplementation ingested 1 h before the game may have a positive effect on players' performance in a first-person shooter by using a Stroop task and testing the players' visual search and shooting abilities. Such findings may encourage coaches and athletes to consider the use of caffeine as a nutritional supplement prior to important competitions to further enhance competitive performance."