Background <p>Researchers have studied shift damping in structures because it is more sensitive than shift frequencies and can indicate structural damage. Changes in hysteresis damping also suggest modifications within structures during cyclic tests. However, the relationship between these two approaches has not been documented, presenting a potential opportunity for research into damage indicators in structural health monitoring.</p> Objective <p>This study examines energy dissipation during the evolution of cycling tests in structural adhesive joints to validate the equivalence between modal and hysteresis damping.</p> Methods <p>Experimental analysis was conducted on test coupons of single-lap adhesive joints mounted on aluminum substrates. A universal cyclic testing machine and vibration data acquisition systems were employed. Hysteresis loops were measured to estimate dissipation energy across the entire cycling process until failure. Concurrently, the frequency response function was measured using an impact hammer, and modal damping was estimated via the half-power method during postprocessing.</p> Results <p>The damping progression followed a bathtub-like behavior, which could predict the residual life of the joints. Changes in measured damping indicate that hysteresis-estimated damping and the sum of modal damping across different resonant frequencies exhibit similar patterns during the cycling process.</p> Conclusions <p>An experimental relationship between hysteresis damping and modal damping during cyclic testing has been established. These findings support the utility of modal and hysteresis damping estimations in enhancing structural health monitoring techniques.</p>