Abdominal muscle strain: Damage to the abdominal muscle due to over-stretching of the muscle tissue. The damage involves tearing the muscle tissue. Small blood vessels may also be damaged which can cause bruising. The symptoms may vary from mild to severe depending on the severity of the damage. More detailed information about the symptoms, causes, and treatments of Abdominal muscle strain is available below.
Buttercream (also known as butter cream, butter icing, and mock cream) is a type of icing or filling used inside cakes, as a coating, and as decoration. In its simplest form, it is made by creaming butter with powdered sugar, although other fats can be used, such as margarine or lard.
true buttercream made with butter and egg whites and whatnot does not do well in heat (by which i mean it will melt). if you can keep it relatively cool for the 4 hour car ride it should be fine (though technically as far as sanitation regulations are concerned it would not be [see the bottom of my post]), so with real buttercream frosting i would not chance it.