MYF5 and sarcopenia: In addition, several myogenic regulatory factors—e.g., myoblast determination protein 1, myogenin, or myogenic factors 5 (Myf5) and 6 (Myf6, also known as myogenic regulatory factor 4, Mrf4, or herculin)—can help fight age-related sarcopenia and frailty, all of them modulated by aerobic or resistance exercise (87–89).