Strength-training barbell design has historically emphasized metallurgy and external surface treatments; interior mechanical tuning has been largely ignored. This study proposes a novel, manufacturable approach in which a polymer-derived silicon-oxycarbide (SiOC) lattice is used as an internal functional insert to tune dynamic response and fatigue performance of a hollow steel barbell bar. Rather than pyrolysing within the finished bar (which compromises steel metallurgy), a porous SiOC lattice was fabricated and pyrolysed externally from a preceramic polymer precursor, then dimensionally integrated and bonded into the bar’s hollow core. The compliant ceramic network reduced vibration amplitudes during standard dynamic lifts while preserving the whip characteristics needed for Olympic lifts. Comparative mechanical testing and finite-element analysis indicate that SiOC porosity and lattice topology can be tuned to trade off vibration damping, bending stiffness, and fatigue life for discipline-specific performance. Prototype inserts increased predicted fatigue life by up to 80% for powerlifting-type loading regimes while producing negligible mass penalty (<2%). The findings demonstrate a feasible pathway for incorporating polymer-derived ceramics as internal mechanical regulators in sports equipment, enabling a new design space where tailored internal architectures, rather than only external metallurgy, define performance.

Keywords: Polymer-derived silicon-oxycarbide, Vibration damping, Bending stiffness, Fatigue life.