Effects of caffeine on glycaemia and blood pressure in women practising Muay Thai

This study investigated the acute effects of caffeine supplementation (210 mg; ~2.7 mg/kg) on glycemic and hemodynamic responses in eight female Muay Thai practitioners using a randomized crossover design. Participants received caffeine or placebo before a structured training session, with assessments performed at rest, 20 minutes post-ingestion, 30 minutes of exercise, and post-exercise. The results demonstrated that caffeine significantly reduced blood glucose levels during exercise, particularly when administered in the second experimental period, suggesting an order-dependent effect of supplementation. No significant differences in heart rate were observed between conditions. For systolic, diastolic, and double product blood pressure, complex interactions modulated by the experimental sequence were identified, indicating an influence of familiarization or carryover effect. It is concluded that caffeine exerts contextual metabolic and hemodynamic effects in female athletes, with its effectiveness being influenced by the order of administration and habituation. Practical applications include recommending the periodization of caffeine use (3–6 mg/kg) close to key sessions or competitions, avoiding habitual daily consumption to optimize cardiovascular adaptations, and individually monitoring glycemic and blood pressure responses to adjust the dose and timing of intake.