🎯 Título: Cafeína y paraxantina en el rendimiento en remo
📌 En breve: La combinación de cafeína y paraxantina mejoró el rendimiento en una prueba de 2000 m de remo, mientras que cada sustancia por separado no mostró un efecto ergogénico claro.
🔬 Puntos clave:
### El estudio
14 remeros universitarios varones completaron pruebas cronometradas de 2000 m en ergómetro bajo cuatro condiciones (cafeína + paraxantina, cafeína + placebo, paraxantina + placebo, y placebo, 200 mg cada sustancia), en un diseño aleatorizado, doble ciego y cruzado.
### Rendimiento
La combinación de cafeína y paraxantina se asoció con un tiempo más rápido y mayor potencia media frente al placebo (p = 0,044; d de Cohen = 0,30, efecto pequeño). Por separado, ni la cafeína ni la paraxantina mostraron evidencia clara de mejora del rendimiento en esta muestra, aunque las estimaciones favorecían a ambas frente al placebo.
### Sueño
Las condiciones que incluían cafeína se asociaron con peor calidad subjetiva del sueño, mientras que la paraxantina sola mostró resultados más favorables para el sueño.
🎯 Aplicación clínica para LATAM: Para remeros que buscan maximizar el rendimiento sin afectar el sueño —relevante en entrenamientos vespertinos—, la paraxantina podría ser una alternativa a explorar, aunque se necesita más evidencia antes de recomendarla de forma general.
⚠ Limitaciones: La muestra fue pequeña (14 remeros) y el sueño se evaluó con escalas subjetivas, no con medición objetiva, según reconocen los propios autores.
Background
Although caffeine is widely used in athletes due to its ergogenic effects, the effects of its main metabolite, paraxanthine, on performance and sleep have not been adequately investigated.
Purpose
This study aimed to comparatively investigate the effects of caffeine and its main metabolite paraxanthine on rowing performance and sleep quality.
Methods
The study was designed as a randomized, double-blind, crossover study and included 14 male university-level rowers (21.6 ± 1.9 age; 2.2 ± 1 years of rowing experience). The participants participated in 2000-m rowing ergometer time trials under four different supplementation conditions (caffeine + paraxanthine, caffeine + placebo, paraxanthine + placebo, and placebo with 200 mg each). Performance data (completion time, mean power, and heart rate), sleep quality, and daytime sleepiness were assessed by subjective scales. The data were analyzed by repeated-measures analysis of variance (ANOVA) and Bonferroni post-hoc tests.
Results
Compared with the placebo, the combined caffeine + paraxanthine condition was associated with faster 2000-m performance and higher mean power output (p = 0.044; Cohen's d = 0.30). Caffeine alone and paraxanthine alone did not show clear evidence of performance improvement in this sample, although estimates favored both conditions versus placebo. Conditions containing caffeine were associated with poorer subjective sleep quality, whereas paraxanthine alone showed more favorable sleep-related outcomes.
Conclusion
These results indicate that the combined ingestion of caffeine and paraxanthine elicited the most pronounced performance benefits, while paraxanthine alone did not demonstrate clear standalone ergogenic efficacy at the administered dose. However, paraxanthine was associated with better subjective sleep outcomes compared to caffeine, suggesting that its potential value may be related more to tolerability rather than superior performance enhancement, particularly for athletes training in the evening. Study limitations, including the small sample size and lack of objective sleep measures, should be considered when interpreting the results.
Practical applications
Paraxanthine may represent a practical option for athletes who prioritize sleep quality or experience sensitivity to caffeine-related sleep disturbances, although further dose‒response studies are required to clarify its ergogenic potential.
Cómo citar:
Bingol Diedhiou A, Yildirim UC, Ozdenk S, Erkan D, Karakulak I, Yildirim Tuncer S, Turğut M, Gundem MC, Bora MV, Akca F. (2026).
Comparative effects of caffeine and paraxanthine on rowing performance and sleep quality: a randomized crossover study.. Journal of the International Society of Sports Nutrition.
DOI: 10.1080/15502783.2026.2650339 ↗ PMID: 41918248 ↗ Acceso al paper: Ver completo ↗
