Adapted boxing can help improve the physical functioning and health-related quality of life (HRQoL) of individuals with Parkinson's disease (PD). Whether these benefits persist longitudinally is unclear. The purpose of this retrospective study was to evaluate the impact of a community-based adapted boxing program on the physical functioning and HRQoL of individuals with PD over 1-1.5 years. Twenty-six individuals with PD agreed to share their results on tests administered upon enrollment in the program (PRE) and ∼431 days later (POST). The tests included the Fullerton Advanced Balance scale, (FAB), the Timed Up-and-Go test (TUG), the 30-second Sit-to-Stand test (30-STS), and the PD questionnaire-39 (PDQ-39). From PRE to POST, performance significantly improved on the TUG and 30-STS tests (both p < 0.001), but not on the FAB (p = 0.79). Over the same period, PDQ-39 scores significantly increased (p = 0.05). No PRE to POST changes surpassed the minimal detectable change threshold. The results of this study suggest that adapted boxing is at worst non-detrimental and at best potentially beneficial for muscle strength, endurance, and functional mobility in individuals with PD. However, adapted boxing probably cannot fully counteract the HRQoL decrements that accompany PD progression.