Cardiovascular endurance and psychosocial health predict short- and long-term BMI-SDS reduction: results from the CHILT III program

This longitudinal study analyzes data from the Children’s Health Interventional Trial (CHILT) III, an 11-month juvenile multicomponent weight management program. The objective is to identify predictors of changes in body mass index standard deviation scores (BMI-SDS), so as to further enable the advancement of existing interventions with sustained impact. This study’s sample consists of 237 children and adolescents with obesity (8–17 years, 54% girls) participating in the CHILT III program between 2003 and 2021. Anthropometrics, demographics, relative cardiovascular endurance (W/kg), and psychosocial health (i.e., physical self-concept and self-worth) were assessed at program entry ( $$t1$$ t 1 ), end ( $$t2$$ t 2 ), and one-year follow-up ( $$t3$$ t 3 ; n = 83). From $$t1$$ t 1 to $$t2$$ t 2 , the mean BMI-SDS was reduced by −0.16 ± 0.26 units ( p < 0.001). Media use and cardiovascular endurance at baseline and improvements in endurance and self-worth over the course of the program predicted changes in BMI-SDS (adj. R 2 = 0.22, p < 0.001). From $$t2$$ t 2 to $$t3$$ t 3 , mean BMI-SDS increased ( M = 0.09 ± 0.29 M = 0.09 ± 0.29 , p = 0.005). Changes in BMI-SDS from $$t2$$ t 2 to $$t3$$ t 3 were associated with parental education, improvements in cardiovascular endurance and physical self-concept, and BMI-SDS, media use, physical self-concept, and endurance level at program end (adj. R 2 = 0.39, p < 0.001). Conclusions : This study highlights the need for comprehensive, sustainable weight management approaches, in order to sustain the initial treatment benefits. In this context, improvements in cardiovascular endurance and psychosocial health could be essential strategies to pursue in practice, as they significantly predicted reductions in BMI-SDS – both pre- to post-intervention and at follow-up. Trial registration : DRKS00026785; date of registration: 13.10.202, retrospectively registered. What is Known: • Childhood obesity is associated with the onset of noncommunicable diseases, many of which are likely to carry into adulthood. Thus, effective weight management strategies for affected children and their families are vital. However, achieving lasting positive health outcomes with multidisciplinary weight management programs remains challenging. What is New: • According to this study, short- and longer-term BMI-SDS reductions are associated to cardiovascular endurance and psychosocial health. These factors should therefore be given even greater consideration in weight management strategies, as they may be important not only in themselves but also for long-term weight loss (maintenance).