Methods for measuring mechanical properties of an object or subject under examination with an ultrasound system and using unfocused ultrasound energy are provided. Shear waves that propagate in the object or subject are produced by applying unfocused ultrasound energy to the object or subject, and measurement data is acquired by applying focused or unfocused ultrasound energy to at least one location in the object or subject at which shear waves are present Mechanical properties are then calculated from the acquired measurement data.