Supplementation with whey isolate and its influence in muscle hypertrophy and strength on amateur athletes: a ramdomized trial

• Autor(a) principal: Duarte, Nuno Miguel da Silva
• Data de Publicação: 2018
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10400.22/13723
• topic: Dietary supplementation; Exercise program; Skeletal muscle; Body composition; Strength training

This review aims to analyze the effects of whey protein supplements in hypertrophy and strength metrics of adult population engaged or not in resistance training (RT) compared with other protein sources or isocaloric placebos. Using a systematic approach, studies were searched through PubMed and Web of Science using the terms “whey”, “muscle”, “resistance” and “strength”, in different combinations as keywords. After exclusion of articles a quality assessment was executed resorting to an adapted Risk of Bias tool by Cochrane, converted to the Agency of Health Care Research and Quality standards. Heterogeneity of trial designs demonstrate a wide variety of findings, however most of the studies reviewed report positive differences in hypertrophy and/or strength metrics. Increased duration of trials and higher leucine content of whey result in lean mass, strength and muscle size increase. Other aspects such as increased total protein intake from diet and tailored training programs greatly influence the effects of whey supplementation resulting in greater gains. Whey supplementation in the context of RT can enhance long term phenotypic adaptations, provided some key factors are controlled such as duration, intensity and frequency of training programs, sufficient protein dietary intake and content of supplement in Branched Chain Amino Acids namely leucine.