This article is focused on the review of studies looking for "candidate genes" and their relationship with physical performance phenotypes in elite athletes. Our goal is to bring to readers what makes some individuals excel in some sports modalities, based on variants in genetic loci and markers. In addition, we assume the necessity to describe by what mechanisms a gene can contribute in physical performance, detailing in each part the cellular, physiological and molecular pathways involved. For this reason, we limited our discussion to a small number of genetic variants: polymorphisms R577X α-actinin 3 gene (ACTN3), C34T AMP deaminase gene (AMPD1), I/D angiotensin converting enzyme gene (ACE), -9/+9 β 2 bradykinin receptor gene (BDKRB2), and 985+185/1170 creatine kinase M gene (CK-M). 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