Med Sci Sports Exerc. 2025 Jul 10. doi: 10.1249/MSS.0000000000003816. Online ahead of print.
ABSTRACT
PURPOSE: This study aimed to investigate how genotype and caffeine habituation influence the acute effects of caffeine ingestion on exercise-induced hemostatic responses in individuals with obesity.
METHODS: Using a randomized, double-blind, placebo-controlled crossover design, 40 physically inactive young men with obesity (age, 22.2 ± 2.3 years; BMI, 34.1 ± 2.7 kg/m2) completed two moderate-to-high-intensity concurrent exercise sessions following ingestion of caffeine (3 mg/kg) or placebo. Blood samples were collected at baseline, after exercise, and after 60 minutes of recovery. Statistical analysis was performed by repeated measures MANOVA.
RESULTS: Acute exercise increased platelet count and aggregation, fibrinogen, F1 + 2, tPA antigen, D-dimer, and clot lysis time, regardless of genotype or caffeine habituation status (P < 0.05). PAI-1 antigen remained unchanged after exercise (P > 0.05) but decreased following recovery (P < 0.01). Caffeine resulted in a greater increase in platelet aggregation, fibrinogen, F1 + 2, and clot lysis time, alongside a blunted increase in tPA antigen levels post-exercise in naïve consumers (P < 0.05). In contrast, habitual caffeine consumers exhibited a mitigated increase in clot lysis time and a greater post-recovery reduction in PAI-1 antigen following caffeine ingestion (P < 0.001). Caffeine’s impact on hemostatic responses to exercise was unaffected by genotype (P > 0.05).
CONCLUSIONS: Moderate-to-high-intensity concurrent exercise induces a transient prothrombotic state in physically inactive individuals with obesity. Acute caffeine supplementation at a moderate dose modulates the hemostatic responses depending on caffeine habituation status rather than CYP1A2 genotype: it exacerbates the prothrombotic response in naïve consumers but attenuates it in habitual consumers.
PMID:40638809 | DOI:10.1249/MSS.0000000000003816
