Abstract: A method for protecting muscles, comprising administering to a subject in need an effective amount of a FU-LING (Poria cocos) extract, tumulosic acid and/or a pharmaceutical acceptable salt of tumulosic acid. In particular, the method of the present invention is for protecting muscle cells against injury, promoting regeneration and repair of muscle, regulating, treating and/or delaying muscle atrophy (especially caused by aging, diseases, and cachexia), or helping normal muscle contraction, maintaining normal muscle physiology, maintaining normal neuromuscular function, maintaining normal energy metabolism, or enhancing energy level.