The Lionheart Series by Ruck Republic is an event series that integrates rucking with various workouts. Spread throughout the year, the series includes four distinct Lionheart ruck events. Each Lionheart event is structured to not only provide a physical workout but also to build camaraderie among participants, fostering a sense of community and mutual support. Although participants are advised to carry a weighted ruckpack, the events are designed to be inclusive, welcoming participants of varying fitness levels, and encouraging them to push their boundaries while ensuring safety and fostering a supportive environment.

The term "Lionheart" is rich in historical and symbolic significance, commonly associated with courage, bravery, and a fearless spirit. Having a "lionheart" means possessing the heart of a lion—a metaphor for showing extraordinary bravery and steadfastness in the face of challenges. It symbolizes a person who confronts difficulties with courage, does not shy away from adversity, and who leads with strength and determination.

The Lionheart Series embodies the ethos of Ruck Republic, which is to strengthen the body and mind through challenging yet rewarding experiences. By participating in all four events throughout the year, individuals have the opportunity to experience a comprehensive fitness journey that exposes them to different types of exercises, promoting overall physical fitness, mental wellness, and community building.

Participants also have a unique opportunity to earn exclusive Lionheart series patches. These patches represent not just personal milestones, but the collective spirit of resilience, teamwork, and enduring strength that defines the Lionheart Series and the Ruck Republic community at large.