BMJ Open. 2026 Jun 19;16(6):e115125. doi: 10.1136/bmjopen-2025-115125.
ABSTRACT
BACKGROUND: Adolescent obesity is increasing worldwide, and a minority of adolescents are meeting recommended physical activity (PA) and dietary guidelines, particularly among adolescents from low socioeconomic areas. There are limited studies qualitatively investigating the engagement in healthy lifestyle behaviours in this population. Therefore, this study aimed to gain a greater understanding of perceived barriers and facilitators of healthy lifestyle behaviours, specifically PA and dietary behaviours, in this under-represented population.
METHODS: Eight semistructured qualitative focus groups with 35 adolescents aged 13-15 years old were conducted across four European countries (Spain, the Netherlands, Greece, UK) following the Theory of Planned Behaviour framework which states that individual behavioural intentions are grounded on attitudes, subjective norms and perceived behavioural control. Discussions were centred on adolescents' PA and healthy eating behaviours and were thematically analysed.
RESULTS: Regarding attitudes, adolescents understood the importance of healthy lifestyle behaviours but often failed to engage in them. Concerning subjective norms, friends and peers were perceived as barriers to PA, except during physical education (PE) classes. Positive relationships between pupils and teachers facilitated PA, and family influence primarily affected dietary behaviours. Regarding perceived behavioural control, the school structures including lack of space and time, as well as limited healthy food options in canteens and the COVID-19 pandemic were barriers to healthy lifestyle behaviours, while mandatory PE classes and school clubs facilitated PA.
CONCLUSIONS: In conclusion, despite adolescents recognising the significance of healthy lifestyle behaviours they often fail to engage in them. Their healthy lifestyle behaviours were influenced by their friends, families and teachers. The school structure and the COVID-19 pandemic were considered barriers to healthy lifestyle behaviours among adolescents.
TRIAL REGISTRATION NUMBER: NCT05002049.
PMID:42320970 | DOI:10.1136/bmjopen-2025-115125