ZMA supplementation does not impact IGF-IGFBPs system or body composition of young athletes

Abstract

IGF-IGFBPs system hormones are known for their anabolic role. ZMA is a supplement consisting of zinc, magnesium and vitamin B6, whose premise is to provide an increase in levels of GH, IGF-1 and testosterone. This hypothetical increase could cause significant changes in body composition. However, studies on its effectiveness are divergent in addition do not evaluate the IGF binding proteins (IGFBPs), which are essential in IGF-1 metabolism. Therefore, this study aimed to analyze the effects of ZMA in IGF-1, IGFBP-3 and testosterone levels. Eighteen male amateur athletes were divided into two groups: ZMA and placebo. Hormone levels and anthropometric characteristics were assessed before and after the 8-week intervention. After the intervention, there were no differences between groups in hormonal levels and anthropometric characteristics. Thus, the results suggest that ZMA do not offer any additional benefits for individuals that has an appropriate diet, either in body composition or in hormone levels.