2.1. Search Strategy
This systematic review and meta-analysis was reported according to the
guidelines of Preferred Reporting Items for Systematic Reviews and
Meta-Analyses (PRISMA) (21). A computerized search was coducted from
inception to August 2020 using various databases including PubMed, ISI
Web of Science, Scopus, and supplementary Google Scholar search. The
following terms and their combinations of MeSH and non-MeSH terms were
applied, including: “beta hydroxy beta methylbutyrate”, “hydroxy
methyl butyrate”, “HMB”, “exercise,” “sport supplements”,
“endocrine response” “cortisol”, and “testosterone”. Reference
lists of all studies were checked for further eligible articles
identification.