Disclosed is a use of a Cistanche tubulosa extract, isoacteoside and/or a pharmaceutically acceptable salt of isoacteoside for the preparation of a drug or a food, wherein the drug or food is used to protect muscles. The drug is especially used for anti-muscle cell injuries, so as to regulate, treat and/or delay muscle loss, in particular due to aging, diseases and/or cachexia. The food is a health food, nutrition-replenishing food or special nutritional food.