Trends in physical fitness among Lithuanian adolescents aged 11–17 years between 1992 and 2022

Background Physical fitness is an excellent marker of general health and performance. We aimed to calculate trends in physical fitness among Lithuanian adolescents between 1992 and 2022. Methods Using a repeated cross-sectional design, body size and physical fitness data for 17 918 Lithuanian adolescents (50.3% female) aged 11–17 years were collected in 1992, 2002, 2012 and 2022. Body mass index (BMI) was calculated from measured height and body mass, with BMI z-scores (zBMI) calculated using WHO growth curves. Physical fitness was measured using the Eurofit test battery, with results converted to z-scores using European norms. With adjustment for zBMI, trends in mean fitness levels were calculated using general linear models. Trends in distributional characteristics were visually described and calculated as the ratio of SDs. Results We found significant large declines (standardised effect size (ES) ≥ 0.80) in 20-m shuttle run and bent arm hang performance, and significant small declines (ES=0.20–0.49) in standing broad jump, plate tapping, sit-and-reach and sit-ups performance. In contrast, we found a significant moderate improvement (ES=0.50–0.79) in flamingo balance performance and a significant negligible improvement (ES<0.20) in 10×5-m shuttle run performance. Poorer trends were observed in low performers (below the 20th percentile) compared with high performers (above the 80th percentile). Conclusion Health-related fitness (ie, cardiorespiratory and musculoskeletal fitness) levels have declined among Lithuanian adolescents since 1992, particularly among those with low fitness. National health promotion policies are required to improve current trends.