FOXO1 and metabolic syndrome: Even when we did not observe a shift into a faster phenotype, we found an increase expression of FOXO1 due to MetS, which has been found to induce the fast phenotype of the muscles (Pudi et al., 2007), and could be one of the factors playing a role on the alterations suffered by slow muscles during the MetS, as reported in other studies (Eshima et al., 2017; Simi et al., 1991; Tallis et al., 2017).