Activity and social correlates of physical fitness in Lithuanian schoolchildren.

Physical fitness (PF) is an important marker of health and well-being. This study aimed to quantify associations of social environment and physical activity (PA) related factors with different aspects of PF among adolescents. The cross-sectional study included 4925 (51% girls) schoolchildren aged 11-18 years. Participants were tested for PF using the Eurofit battery (covering 8 aspects of PF), with their social environment (parents' education, family's and friends' support for PA), personal motivation for PA, actual PA level, and sports participation status were self-reported. Age- and sex- adjusted body mass index (BMI) cut-points were used to classify weight status as overweight or normal weight. Associations were quantified using hierarchical linear regression analysis. Up to 45% of the variability in PF was explained by BMI and environmental factors. While age, sex, BMI and parents' education associated with PF most strongly, personal motivation for PA (R2 = 0.007 on average per aspect of PF), friends' support for PA (R2 = 0.009) and especially sports participation (R2 = 0.014) were also significant correlates of PF. However, familial support for PA and current PA level were typically non-significant correlates. In conclusion, parents' education, sports participation, personal motivation and friends' support for PA should be promoted to foster PF of adolescents.