Physical Activity, Sedentary Time, and Fatness in a Biethnic Sample of Young Children

Abstract

Purpose-To investigate associations of objectively-measured physical activity (PA) and sedentary time (ST) with adiposity in a predominantly bi-ethnic (South Asian and White British) sample of young children.Methods-The sample included 333 children aged 11 months to 5 years who provided 526 crosssectional observations for PA and body composition. Total PA volume (vector magnitude counts per minute (cpm)), daily time at multiple intensity levels (the cumulative time in activity >500 cpm, >1000 cpm, >1500 cpm and so on up to >6000 cpm), and time spent sedentary (<820 cpm), in light PA (820-3907 cpm) and moderate-to-vigorous PA (MVPA: ≥3908 cpm) were estimated with tri-axial accelerometry. Indicators of adiposity included BMI, waist circumference, and the sum of subscapular and triceps skinfold thicknesses. Statistical analyses were performed using multilevel regression and isotemporal substitution models adjusted for confounders. Effect modification by ethnicity was examined. Conflicts of Interest:None of the authors reported a conflict of interest related to the study. Authors' ContributionsThe authors' responsibilities were as follows -PJC: designed and conducted the research, analyzed data, wrote the paper, and had primary responsibility for the final content of the manuscript; SB assisted design of the statistical analysis and critiqued the manuscript; DDB assisted processing of accelerometer data; DDB, SC, JWe, RRCM, JWr, and SEB: designed individual studies, organized and managed data collections, and critiqued the manuscript; all authors approved the final manuscript as submitted. Results-There was no evidence for effect modification by ethnicity (p-interaction≥0.13). In the whole sample, the accumulated time spent above 3500 cpm (i.e. high light-intensity PA) was inversely associated with the sum of skinfolds (β (95% CI) = -0.60 (-1.19 to -0.021) mm per 20 min/d) and the magnitude of association increased dose-dependently with PA intensity (peaking for time spent >6000 cpm: -1.57 (-3.01 to -0.12) mm per 20 min/d). Substitution of 20 min/d of ST with MVPA was associated with a lower sum of skinfolds (-0.77 (-1.46 to -0.084) mm). Europe PMC Funders GroupConclusions-High light-intensity PA appears to be beneficial for body composition in young South Asian and White British children, but higher-intensity PA is more advantageous.

Maternal Adiposity is Associated with Fat Mass Accretion in Female but not Male Offspring During the First 2 Years of Life

“…Offspring PA at 2 years tended to be negatively correlated with their adiposity ( P = 0.08). This is in agreement with a study by Collings et al that showed an inverse association between PA and adiposity in children 11 months to 5 years of age. These findings emphasize the importance of PA beginning in early childhood to possibly reverse or mitigate adverse adiposity accrual that occurs in early infancy.…”

Objectively-measured sedentary time and physical activity in a bi-ethnic sample of young children: variation by socio-demographic, temporal and perinatal factors

“…Data were pooled from three projects that are related to the Born in Bradford birth cohort study [14] and research programme (www.borninbradford.nhs.uk). Two projects were observational studies [15,16] and another was a multiple time-point school-based pilot cluster randomised control trial (RCT) that targeted preschool children [17]. Each study included objective measurement of free-living physical activity in young children living in Bradford, which is one of most deprived and ethnically diverse cities in the UK [18].…”

Associations of TV Viewing Duration, Meals and Snacks Eaten When Watching TV, and a TV in the Bedroom with Child Adiposity

“…Skinfolds of the left triceps and subscapular were measured to the nearest 0.1 mm and were combined to their total sum. Reliability metrics indicated good intra-and interobserver technical error for measurements (5).…”