👤 Glenn Roswal

To explore the association between 24-h movement behaviours and fundamental motor skills in children with intellectual disabilities using compositional data analyses and to investigate the 'dose-effect' characteristics of the reallocation between 24-h movement behaviours and fundamental motor skills. A cross-sectional study was conducted among 306 children with intellectual disabilities aged 6-10 years from 12 special education schools in Beijing and Jinan between 10 September 2023 and 27 March 2024. The ActiGraph GT3X+ accelerometer was used to estimate the amount of time spent in 24-h movement behaviours. The Test of Gross Motor Development-2 was applied to assess fundamental motor skills. The compositional isotemporal substitution was utilized to analyse the relationship between 24-h movement behaviours and fundamental motor skills. (1) After controlling the gender, age and intellectual disability level, MVPA of children with intellectual disabilities was positively associated with their FMS total score, locomotor skills and object control skills (β Special education school administrators, teachers, parents and guardians should consider 24-h movement behaviours as a whole and pay attention to their impact on children with intellectual disabilities. In the process of promoting FMS in children with intellectual disabilities, ensuring adequate sleep and trying to reallocate time from SB to MVPA and LPA may be effective methods. Show less

To examine the association between 24-hour movement behaviors and depressive symptoms in older adults using compositional data analysis, and to investigate the dose-response characteristics of time reallocations between movement behaviors in relation to depressive symptoms. A cross-sectional study was conducted among 1093 urban-dwelling older adults aged 60 years and above in selected communities of Jinan City, Shandong Province, China, between April 2024 and September 2024. The Chinese version of the International Physical Activity Questionnaire-Long Form (IPAQ-LF) was used to estimate time spent in moderate to vigorous-intensity physical activity (MVPA), light-intensity physical activity (LPA), sedentary behavior (SB), and sleep (SLP) across a typical 24-hour day. The Chinese version of the Patient Health Questionnaire Depression Scale-9 item (PHQ-9) was applied to assess depressive symptoms. Compositional isotemporal substitution models were employed to explore the associations between time reallocations among 24-hour movement behaviors and depressive symptoms, accounting for the co-dependent nature of time-use data. (1) The geometric means of time spent in MVPA, LPA, SB, and SLP were 25.33 minutes, 141.26 minutes, 738.10 minutes, and 455.15 minutes, respectively. Variation matrix analysis revealed the highest log-ratio variance between MVPA and SB (0.168), and the lowest between SLP and SB (0.031). (2) The prevalence of screening-positive depressive symptoms was 16.29% among Chinese urban older adults. (3) Results from compositional linear regression models showed that time allocated to MVPA, LPA, and SLP (relative to the remaining movement behaviors) was negatively associated with depressive symptoms, while time spent in SB was positively associated. (4) Dose-response analysis further indicated that: (a) MVPA substitutions with other movement behaviors exhibited nonlinear and markedly asymmetric effects on depressive symptoms; (b) replacing MVPA with LPA, SB, or SLP resulted in increasingly larger changes in predicted scores as substitution duration increased, whereas the reverse substitution (MVPA for other movement behaviors) produced progressively smaller changes; and (c) substitutions between SB and LPA displayed linear and symmetrical effects. The findings provide evidence of an association between 24-hour movement behaviors and depressive symptoms in Chinese urban-dwelling older adults and reinforce the importance of achieving a balance between different types of movement behaviors over a 24-hour period for mental health. Show less