A fitness device in the form of a mortar and pestle system designed to be powered manually by a user's arm(s) in a gravity-driven operation, providing a unique and customizable fitness experience. More particularly, a fitness device comprising a stationary mortar component, a pestle component having a weighted element removably secured thereto, and a malleable synthetic material removably disposed within the mortar component. In operation, an individual can grip the handle of pestle component, and using one or both arms, pound the synthetic material to create a unique and challenging workout