Predictors of long-term recreational exercise participation in adolescents and young adults.

The individual and societal factors influencing long-term recreational exercise participation during the transition from adolescence to young adulthood are not well explored. We modelled latent longitudinal recreational exercise trajectories spanning 8 years from age 16 to 24, and examined demographic, socioeconomic, behavioural, academic, and psychological predictors at age 15 of trajectory-group membership. We also explored whether trajectories were associated with health, mental health, and educational achievement at age 25. Finite mixture modelling was conducted with population-based longitudinal cohort study data collected from 2006-2017 by the Longitudinal Survey of Australian Youth (LSAY). The study sample comprised 9,353 students (49% female) from 356 Australian schools. Self-reported recreational exercise frequency data were collected in 2007, 2008, 2009, 2011, and 2014. Longitudinal latent trajectories of reported recreational exercise participation were estimated using group-based trajectory modelling for two scenarios: daily/guideline-adherent exercise versus non-daily exercise (model 1) and exercise at least once weekly versus exercise less than once weekly (model 2). Four distinct classes of long-term recreational exercise participation were identified for each model. Model 1: guideline-adherent exercisers (17.9% of the sample), never guideline exercisers (27.5%), guideline drop-outs (15.2%) and towards guideline (39.4%). Model 2: regular weekly (69.5% of the sample), decreasing (17.4%), increasing (4.8%), and infrequent (8.3%). In both models, predictors at age 15 for lower long-term exercise participation included female gender, lower self-efficacy, sport participation and parental socioeconomic status, and higher screen-time and academic literacy. At age 25, people in the guideline-adherent exerciser trajectory (model 1) reported better general health, whereas people in the regular weekly trajectory (model 2) had better general health and reduced rates of psychological distress, were happier with life and were more optimistic for the future relative to participants from other trajectory groups. Interventions and health-promotion activities to support sustained engagement in recreational exercise should particularly address the needs of females, people with low self-efficacy, reluctant exercisers, higher academic achievers, and youth experiencing socioeconomic disadvantage.