Musashi RNA Binding Protein 2 is not Involved in Skeletal Muscle Hypertrophy Following Resistance Training

The progressive loss of skeletal muscle mass and strength that occurs with age is known as sarcopenia. Skeletal muscle is primarily composed of two types of muscle fibers, slow-twitch and fast-twitch fibers, based on their contractile properties. With aging, selective atrophy is observed in fast-twitch fibers. Resistance training improves skeletal muscle mass and strength. Resistance-training-induced muscle hypertrophy occurs in fast-twitch fibers rather than in slow- twitch fibers. Musashi RNA-binding protein 2 (MSI2) has been reported as a positive regulator of skeletal muscle mass and fiber types, and MSI2 deficiency leads to muscle atrophy and reduction of fast-twitch fibers, specifically type IIa muscle fibers. However, the effects of resistance training on MSI2 in skeletal muscle are unclear.