Purpose: Physical activity (PA) is proposed for long-term problems after traumatic brain injury (TBI) with mood, quality of life, and participation. However, COVID-19 mitigation strategies resulted in widespread closures of community-based fitness centres, including one housing a peer-assisted PA program (TBI-Health). The purpose of this study was to provide an in-depth exploration of COVID-19's impact on the TBI-Health program for adults with moderate-to-severe TBI and determine how their PA behaviours could be supported in the pandemic.

Methods: Interpretative phenomenological analysis was employed to collect and analyze data from semi-structured Zoom-facilitated interviews with seven female and nine male adults with moderate-to-severe TBI (including program participants and mentors).

Results: Three major themes were identified. Need for PA after TBI included specific benefits of PA after TBI and desire for an adapted PA program. Lasting Impacts of the TBI-Health Program identified belonging to the TBI-Health community, benefits, and knowledge transfer from the program. Resilience and Loss through the Pandemic comprised the repercussions of COVID-19, loss of the PA program, adapting PA to the pandemic, and resilience after TBI.

Conclusion: This study provides insights about impacts of participating in community-based peer-assisted PA programs after moderate-to-severe TBI and ways to support PA in unforeseen circumstances.IMPLICATIONS FOR REHABILITATIONOur community-based peer-assisted physical activity program for adults with moderate-to-severe traumatic brain injury (TBI) promoted a range of daily and social activities.Outdoor group-based physical activity programs provide physical activity and social opportunities for adults with moderate-to-severe TBI when indoor physical activity is restricted.Community-based peer-assisted physical activity programs can assist with posttraumatic growth after moderate-to-severe TBI.