Lifestyle trajectories of boys and girls during the transition to secondary school in British Columbia, Canada, before and during the COVID-19 pandemic

The transition to secondary school was associated with less healthy lifestyles, with variations by gender and pandemic exposure. To develop targeted interventions that promote positive habits during this critical life stage, it is necessary to identify the mechanisms driving these changes, as they may also reflect other developmental or environmental influences coinciding with the transition. Importantly, interventions should also address behavioral changes that occurred during the pandemic, particularly increases in recreational screen time that may persist into adulthood.