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Abstract

La literatura científica referente a la evaluación del consumo de suplementos nutricionales deportivos(SND) en deportes de fuerza, como el powerlifting, es escasa, y la mayoría de estudios posee metodologías de baja calidad, habiendo creado mitos y pseudociencias en el sector. Con objeto de dar recomendaciones sobre SND en base a nivel de evidencia científica, el Australian Institute of Sport (AIS) ha creado una clasificación de SND basada en nivel de evidencia científica.Objetivos: evaluar las posibles diferencias en el patrón de consumo y elección de SND en powerlifters internacionales y nacionales. Materiales y Métodos: 32 powerlifter (10 de nivel internacional y 22 nacional) rellenaron un diario de consumo de SND durante 72 horas.Análisis Estadístico: Se realizó un test no paramétrico de U de Mann-Witney para muestras independientes con objeto de comprobar diferencias en el número de suplementos totales consumidos,así como el número de suplementos consumidos de cada categoría establecida por el AIS. Además, se aplicó un test de χ2 para comparar las diferencias en la frecuencia de consumo de suplementos entre los deportistas de distintas categorías. El nivel de significación estadística se fijó en p<0,05. Resultados: No se observaron diferencias en el número de SND consumidos entre powerlifters de nivel internacional vs nivel nacional (3,20± 2,44 vs 3,32± 2,57 F=0,069, P=0,903). Tampoco se pudo observar diferencias en relación al consumo de SND en ningunas de las categorías basadas en nivel de evidencia descritos por el AIS ni en la proporción de utilización de los distintos SND consumidos (p>0,05).Conclusiones: Aunque los powerlifters internacionales tendieron a consumir suplementos con un mayor nivel de evidencia científica, no se alcanzaron diferencias estadísticas significativas y, por tanto, no se cumplió nuestra hipótesis.
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La nutrición deportiva es un campo en constante evolución con cientos de trabajos de investigación publicados anualmente. El estrecho margen existente en el deporte entre el éxito y la derrota, y en busca de una mejora del rendimiento, hace que muchos deportistas acudan al consumo de suplementos nutricionales (SN). A pesar de ser un mercado con grandes ventas mundiales, en la actualidad los deportistas se muestran confusos a la hora de elegir qué SN consumir o cómo tomarlo. Según estudios actuales y en relación con el número de SN existentes en el mercado, son muy pocos los SN que cuentan con respaldo científico. En base a ello, no es de extrañar que el potencial consumidor o consumidor esté confuso sobre si debe utilizar SN o no, cuál comprar, dónde hacerlo y cómo tomarlos. Los estudios actuales sitúan el consumo de SN entre el 39% y el 94% de la población deportista, y este varía en función de diferentes variables. Asegurar una buena información para que el deportista y su entorno puedan tomar una decisión adecuada, es de vital importancia, ya que debemos asegurarnos un correcto criterio en la elección de los SN en base a su seguridad, su eficacia y su legalidad. Este capítulo nace de la necesidad de abordar de un modo sencillo y didáctico los principios básicos en la elección de los SN, para garantizar una buena selección bajo unos criterios profesionales y adecuados.
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