Background
Longitudinal studies report a global decrease in PA levels during adolescence and young adulthood. PA influences risk-taking such as smoking or drinking in adolescents and young adults (AYAs), however evidence regarding associations between both behaviours is scarce. Hence, the aim of our longitudinal study was to examine PA level changes in a cohort of AYAs and to evaluate their association with the engagement in risky behaviours (tobacco use, cannabis consumption, alcohol misuse, disordered eating patterns and Internet addiction).
Methods
Data were retrieved from the first and third waves of the GenerationFree study (2015-2016 and 2017- 2018 respectively) conducted amongst 1386 AYAs aged 15 to 24 in the 11 post-mandatory schools in the canton of Fribourg in Switzerland. Respondents were divided into four groups according to the changes in their PA levels between T1 and T3: Actives (n = 224; 16.2%), Increasers (n = 157; 11.3%), Decreasers (n = 210; 15.1%) and Inactives (n = 795; 57.4%). Associations with aforementioned risky behaviours were examined through bivariate analyses at first. All statistically significant variables were then included in multivariate analyses. Results are given using relative risk ratios (RRR).
Results
The majority of AYAs in our study were inactive during the studied period and only one in six were physically active. In comparison to Actives, our multivariate analyses revealed a positive association between Increasers and smoking at T3 (RRR 2.154), between Decreasers and smoking at T3 (RRR 1.900), and between Inactives and smoking at T1 (RRR 1.952) and at T3 (RRR 2.218). They also revealed a negative association between Decreasers and alcohol misuse at T1 (RRR 0.522) and between Inactives and alcohol misuse at T3 (RRR 0.507). However, we found an increased risk for alcohol misuse in Decreasers at T3 (RRR 2.092). At T3, Inactives were more likely to be at risk for developing an eating disorder (RRR 1.675) than Actives. We did not find any relationship between PA and cannabis use, nor between PA and Internet misuse.
Conclusion
The existence of associations between PA and risky behaviours during adolescence and young adulthood is concerning. We recommend that public health authorities, schools and sports clubs work together in order to prevent risk-taking in active young people.