Disclosed is a method of treatment or prevention of frailty in an elderlypatient, particularly having an age of 60 orolder. The method provides the concomitant parenteral administration of acombination of an anabolic steroid and a vitamin Dcompound. A preferred combination comprises nandrolone decanoate andcholecalciferol (vitamin D3). The invention, in a furtherpreference, provides a booster therapy to support frail elderly that haveundergone hospitalization or surgery to retainindependence and regain their regular physical and mental activities.