title: [Effectivity in the use of protein supplements in resistance training: systematic review].
abstract: To increase strength and lean body mass, protein has become one of the most popular supplements among athletes. The aim of this study was to analyze the effect of protein supplementation on body composition. A systematic review of the randomized controlled trials (RCT), published in MEDLINE/PubMed and SciELO up to April 10, 2009, was conducted. All RCT conducted in healthy subjects with interventions of six or more weeks were included. Nine studies fulfilled the inclusion criteria, and three of them had level 3 of evidence. Among these studies, the increase of lean mass ranged from 0.8 to 1.9 kg. However, the study with the longest term had duration of 12 weeks. Therefore, the evidence does not support the recommendation for the consumption of protein supplements among healthy individuals.
authors.affiliation: Universidad Autónoma de Baja California, Tijuana B.C., México.
authors.forename: A L
authors.initials: AL
authors.lastname: Armendariz-Anguiano
authors.forename: A
authors.initials: A
authors.lastname: Jiménez-Cruz
authors.forename: M
authors.initials: M
authors.lastname: Bacardi-Gascón
authors.forename: M E
authors.initials: ME
authors.lastname: Pérez-Morales
mesh_terms: D001823:Body Composition / Q000187:drug effects*; D004044:Dietary Proteins / Q000008:administration & dosage*; D019587:Dietary Supplements; D005260:Female; D006801:Humans; D008297:Male; D053580:Muscle Strength; D018482:Muscle, Skeletal / Q000187:drug effects*; D016032:Randomized Controlled Trials as Topic; D055070:Resistance Training / Q000379:methods*; D016896:Treatment Outcome
chemical_list: D004044:Dietary Proteins