PROBLEM TO BE SOLVED: To provide a muscle differentiation-promoting agent that is effective at a low dose.SOLUTION: According to the invention, provided are a composition for promoting muscle differentiation that contains biotin as an active ingredient； and a composition for the treatment and prevention of diseases or symptoms in which muscle differentiation promotion is effective for the treatment or prevention thereof. According to the invention, compositions for the increase of muscle mass, myodynamia enhancement, muscle-atrophy inhibition, and muscle fiber hypertrophy promotion are also provided, containing biotin as an active ingredient.SELECTED DRAWING: None【課題】 低用量で有効である筋分化促進剤の提供。【解決手段】 本発明によればビオチンを有効成分として含んでなる筋分化促進のための組成物と筋分化促進がその治療または予防に有効である疾患または症状の治療および予防のための組成物が提供される。本発明によれば、ビオチンを有効成分として含んでなる筋量増加、筋力増強、筋萎縮抑制および筋繊維肥大化促進のための組成物も提供される。【選択図】なし
