Abstract Background Children with underweight or overweight show different physical activity (PA) levels than their peers with normal weight, and PA enjoyment may explain this difference. This cross-sectional study examined whether PA enjoyment mediates the association between weight status and PA in children and adolescents who are overweight or underweight compared to those with normal weight. Methods We analysed questionnaire-based data from 3,718 participants (52.4% male, mean age 10.4 ± 3.7 years) and accelerometer-based data from 1,531 participants (52.1% male, mean age 10.7 ± 3.6 years) of the nationwide MoMo 2.0-Study in Germany (2023–2024). Weight status was categorized according to cut-offs of the International Obesity Task Force into underweight, normal weight, and overweight. PA enjoyment was measured with the short version of the Physical Activity Enjoyment Scale, PA was assessed via MoMo-Physical Activity Questionnaire and with accelerometers (activPAL4). Mediation analyses were performed using Hayes PROCESS mediation macro for total, direct, and indirect effects, adjusted for age, sex, and socioeconomic status. Results PA enjoyment fully mediated the relationship between overweight and PA in questionnaire-based (indirect effect = − 0.104, 95% CI –0.135, − 0.075) and accelerometer-based data (indirect effect = − 0.065, 95% CI –0.100, − 0.034), compared to children with normal weight. For underweight, a small indirect effect emerged for questionnaire-based (–0.035, 95% CI –0.068, − 0.003), but not for accelerometer-based data (–0.025, 95% CI –0.055, 0.003). Conclusions These findings suggest that reduced PA enjoyment partly contributes to lower PA levels among children with overweight, emphasizing the role of motivational factors in this pathway. For underweight, findings were less consistent. Interventions to promote PA in children with overweight may benefit from targeting PA enjoyment as a key motivational pathway.
Tschuschke et al. (Thu,) studied this question.