THE EFFECTS OF GLUCOSE, CAFFEINE, AND COMBINED GLUCOSE-CAFFEINE SUPPLEMENTATION ON AEROBIC PERFORMANCE IN UNDERGRADUATE STUDENTS

Abstract

Objective: This study aimed to investigate the acute effects of glucose, caffeine, and glucose-caffeine combined mouthwash on specific physiological and sensory responses in college students during submaximal aerobic exercise. Methods: This single-blind randomized controlled trial enrolled 45 healthy male college students aged 18 to 22 years. Based on baseline fitness levels, participants were randomly assigned to three groups (n = 15 per group) using a serpentine allocation method: a 6% glucose group, a 10 mg caffeine (dissolved in 25 mL) group, and a glucose-caffeine combined mouthwash group. All participants underwent Åstrand-Rhyming submaximal aerobic dynamometer testing. Mean arterial pressure (MAP), heart rate (HR), estimated VO2, and subjective fatigue level (RPE) were measured before and after exercise. Paired-samples t-tests were used for intragroup comparisons. Results: All three mouthwashes significantly increased mean arterial pressure (MAP) and heart rate (HR) (all p < .001). No statistically significant change was observed in estimated oxygen uptake (VO2). Subjective perceived fatigue (RPE) responses differed under different conditions. No significant differences were found in any variables among the groups. Conclusion: The acute physiological responses induced by glucose, caffeine, and glucose-caffeine mixed mouthwashes were similar. Due to the lack of a placebo (water) control group, these variations cannot be attributed to specific mouthwashes. Future research should employ effective methods for measuring acute exercise performance and include a placebo control group.

Keywords: Mouthwash, Glucose, Caffeine, Enhancer, Submaximal Intensity Exercise, Aerobic Exercise Performance