Caffeine solutions (1.2% w/v caffeine solution) were prepared in an equivalent saccharin base to ensure indistinguishability within the Falcon Sterile Tube and agitated for 30 seconds on a vortex mixer. Participants were instructed to avoid intense activity 24 hours before testing, observe a 2-hour fast before sessions, and abstain from caffeinated products on test days. The following three sessions were test trials conducted between 15.00 h and 17.00 h at 32°C and 40% humidity.

CHO solutions (6% w/v glucose solution) were prepared in an equivalent saccharin base to ensure indistinguishability within the Falcon Sterile Tube and agitated for 30 seconds on a vortex mixer. Participants were instructed to avoid intense activity 24 hours before testing, observe a 2- hour fast before sessions, and abstain from caffeinated products on test days. The following three sessions were test trials conducted between 15.00 h and 17.00 h at 32°C and 40% humidity.

Only exercise was performed without any condition.

Participants' solutions were prepared in separate Falcon Sterile Tubes: LSPTCAFF (1.2% w/v caffeine solution, Nature's Supreme). An MRI was performed before the LSPT. The solution was sweetened with non-caloric artificial sweeteners consisting of sucralose. The caffeine solution was prepared in an equivalent saccharin base and shaken for 30 seconds in a vortex mixer to ensure distinguishability. Participants swished the solution in their mouth for 10 seconds before LSPT and then emptied it back into the container to be weighed again. To ensure that the solutions were not swallowed, the containers were measured before and after all MRs using a full precision balance (Etekcity, USA) accurate to 1 g/0.04 oz.

Participants used a Polar H10 heart rate (HR) transmitter synchronized with a Polar V800 watch to track the HR throughout the session. Participants' heart rate mean, heart rate peak and heart rate percentage were recorded.

Exercise intensity in all test sessions was quantified using the rating of perceived exertion (RPE), which employs a category ratio scale ranging from 6 to 20. This scale has recently been applied in sports psychology to assess effort related to emotions and performance during competitive events.

all participants completed the exercise enjoyment scale (EES), which comprises eight items rated on a 1-7 Likert scale. This scale has been validated to measure enjoyment in Turkish adolescents and adults. To assess subjective mental fatigue levels, participants were instructed to indicate their degree of mental fatigue on a Visual Analog Scale (VAS).

Participants were informed that the LSPT was a timed performance assessment and instructed to complete it as expeditiously as possible while minimizing penalties. The LSPT comprises 16 passes: eight short passes to red and white targets 3.5m from the passing zone and eight slightly longer passes to green and blue targets 4m away. Targets were constructed by affixing colored cards (0.3 x 0.6m) to the center of standard gymnasium benches, with a vertical aluminum strip (0.1 x 0.15m) fixed to the target's center for auditory feedback on successful passes. Four randomized passing sequences were generated. An examiner announces that the subsequent target color is released immediately after the previous pass. A stopwatch measured the test duration, commencing when the participant moved the ball into the passing zone and concluding when the final pass contacted the target area.

Before breakfast, participants had their weight (kg) measured using a body composition analyser (BC-418MA, Tanita Corp., Tokyo, Japan). This device utilises bioelectrical impedance technology using multiple frequencies (ranging from 1 kHz to 50 kHz) to comprehensively assess body composition parameters.

Before breakfast, participants had their height (cm) measured using a body composition analyser (BC-418MA, Tanita Corp., Tokyo, Japan). This device utilises bioelectrical impedance technology using multiple frequencies (ranging from 1 kHz to 50 kHz) to comprehensively assess body composition parameters.