ArticleNutrition & metabolism2021
Caffeine improves biochemical and specific performance after judo training: a double-blind crossover study in a real judo training situation.
Article in Nutrition & metabolism, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 6 papers, 3 of them syntheses that pooled it.
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Who cites it
6 citing papers in PubMed, 3 syntheses or guidelines pooled it, 14 citations in OpenAlex.
- Advantages of different dietary supplements for elite combat sports athletes: a systematic review and Bayesian network meta-analysis.Scientific reports · 2025Pooled it
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- Pooled it
- Performance-enhancing effects of caffeine and L-Theanine among Iranian elite wrestlers: a focus on cognitive and specific physical performance.Journal of the International Society of Sports Nutrition · 2025Trial
- Preliminary Research towards Acute Effects of Different Doses of Caffeine on Strength-Power Performance in Highly Trained Judo Athletes.International journal of environmental research and public health · 2022Trial
- Acute caffeine strategies for improving performance in combat sports: a structured narrative review.Frontiers in physiology · 2026Review
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Authors and funding
10 authors at 4 institutions in 2 countries.
Funding
Abstract
backgroundNutritional ergogenic aids are foods or nutrients that can improve physical performance. Among these foods with ergogenic properties, caffeine has shown that it can increase the fat catabolism, strength, and improve the cognition and time reaction of an athlete, therefore, it is hoped that it can improve the performance of judokas. This study through a double-blind crossover (supplement X placebo) protocol, investigated the effects caffeine supplementation (single capsule containing 5 mg/kg body mass intake 60 min before the session) on biochemical, anthropometrical, physical, subjective and hemodynamic variables measured before, during and after two typical judo trainingcxs sessions (120-min: 40-min of gymnastics; 40-min of specific technics and; 40-min of judo combat).
methods8 high-level athletes (21.4 ± 2.0 years; 83.6 ± 15.2 kg; 1.8 ± 0.1 m; 17.9 ± 7.0 Fat%) were evaluated before and after each training for body mass, hydration, upper and lower limb power, performance in the special judo fitness test (SJFT), free fatty acids (FFA) in plasma, uric acid, glucose, lactate, heart rate, and pain. In addition, heart rate, FFA in plasma, uric acid, glucose, lactate, rating of perceived exertion and pain were assessed during the training.
resultsAt 120 min, supplementation resulted in a higher concentration of plasma FFA (1.5 ± 0.5 vs. 1.0 ± 0.3 mmol/L; p = 0.047) and lactate (4.9 ± 1.8 vs. 3.0 ± 1.2 mmol/L; p = 0.047), and a lower concentration of uric acid (5.4 ± 0.9 vs. 7.0 ± 1.5 mg/dL; p = 0.04). Supplementation also resulted in performance maintenance (fatigue index) in the SJFT (Δ0.3 ± 2.0 vs Δ1.7 ± 2.5, for caffeine and placebo respectively, p = 0.046). No adverse effects were observed.
conclusionBased on the applied dose, intake time, and sample of this study, we can conclude that caffeine produces an ergogenic biochemical effect, and improves performance in judo athletes.
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