The COVID-19 pandemic has increased health inequalities by altering patterns of engagement with a mass participation event after resumption post-lockdown

The global epidemic in physical inactivity has been exacerbated by lockdowns with concerning health inequalities accentuated as a result. Studies are needed of post-lockdown levels of activity to determine if there are lasting impacts beyond lockdown. This study uses parkrun in Scotland as a model system to address this urgent question. Generalised linear mixed models were used to identify patterns in the attendance, gender, age and performance of 500,000+ parkrun participations in Scotland for the year before the pandemic and the first year after lockdown. Total weekly attendance in Scotland had been increasing year-on-year but fell by 13% from 7,649 (95% CI 7,275 to 8.024) in the final-year pre-lockdown to 6,612 (95% CI 6,260 to 6,963) in the first-year post-lockdown. Attendance drops were disproportionately larger at events with larger attendances prior to lockdown. There was a disproportionate loss of female participants in more deprived areas. The gender gap in participation had been narrowing before lockdown but widened from 54.02% (95% CI 53.85 to 54.19%) in the final-year pre-lockdown to 56.29% male (95% CI 56.09 to 56.49%) in the first-year post-lockdown. The age of participants increased from 44.94 (95% CI 44.90 to 44.98) before lockdown to 46.58 (95% CI 46.53 to 46.64) after lockdown. The age gap between the genders widened after lockdown particularly at larger events and in more deprived areas. Performance was declining before lockdown but increased from 55.02% (95% CI 54.96 to 55.06%) to 55.93% (95% CI 55.88 to 55.97%) after lockdown. The pandemic has reduced attendance at parkrun in Scotland and the loss of participants has been non-random increasing health inequalities affecting women, the least fit and those in deprived areas. Some former participants are also now avoiding larger mass participation events. Investment and management strategies will be needed to address these worsening inequalities.