“…Since the concept of myokines was introduced in 2003 (Pedersen and Febbraio, 2012), more than 300 myokines have been identified in the last 20 years, such as interleukin-6 (IL-6), interleukin-15 (IL-15), fibroblast growth factor 21 (FGF21), myostatin, among others, which also includes irisin. These muscle factors have been shown to be involved in adipose tissue, liver, bone (Trayhurn et al, 2011;Zymbal et al, 2019), central nervous system (Voss et al, 2019;Lee et al, 2021), and immune system (Flori et al, 2021). They play a role in driving browning of white fat (Lee et al, 2014), insulin-sensitive states (Lee et al, 2015), optimizing whole-body energy metabolism, preventing metabolic diseases, and playing a protective role in low-level inflammation on a systemic scale (Tanabe et al, 2017;Flori et al, 2021).…”