Participation in moderate- to vigorous-intensity physical activity (MVPA) during childhood provides numerous physical, psychosocial, and cognitive health benefits.^1-3 However, most US youth participate in less MVPA than the recommended 60 min/d.⁴ Organized sports participation, as a leisure-time activity, has been promoted as an effective strategy to increase physical activity (PA) among youth.^5,6 Because sports is a subset of PA, it is not surprising to find a strong cross-sectional association between organized sports participation and MVPA among youth.^7-11 Longitudinal studies have also reported a positive association between organized sports participation and PA during adolescence.¹² These data suggest that consistent participation in organized sports during the growing years is associated with healthy MVPA habits. In reality, of the 84% of US youth who join organized sports, 45% will stop participation at some point during childhood and adolescence.¹³ Therefore, it is important to understand whether any participation in organized sports helps youth to develop healthier MVPA habits compared with never participating in sports at all.

Pediatric patients frequently present with illnesses strongly suggesting infection, but without a clearly identified etiology. Our center has recently added a commercially available plasma metagenomic sequencing assay to its available diagnostic testing. Our experience with the first 100 tests suggests that this technology has good clinical performance with >90% sensitivity.

Objective: To test the hypothesis that individuals who are active but who decrease physical activity (PA) over time have a higher risk of becoming obese in young adulthood, when compared to individuals who are consistently active throughout childhood and adolescence.Methods: Iowa Bone Development Study cohort members (242 males and 251 females) participated in accelerometry assessments, dual‐energy X‐ray absorptiometry scans, and dietary questionnaire surveys at ages 5, 8, 11, 13, 15, 17, and 19 years. Group‐based trajectory analyses identified distinct trajectory patterns of moderate‐ to vigorous‐intensity PA (MVPA), percentage of body fat, and energy intake. A multivariable logistic regression model was fit to estimate the odds of “becoming obese” based on the MVPA trajectories, adjusted for mother's education, somatic maturation, and energy intake.Results: Among males, 74.7% had a “normal” body fat pattern, 14.6% had a “becoming obese” pattern, and 10.7% had a “consistently obese” pattern, while among females, the percentages were 58.6%, 28.6%, and 12.8%, respectively. Participants who were active (≥45 min MVPA) as children but decreased MVPA with age were more likely to become obese, compared to consistently active participants (adjusted OR = 2.77; 95% CI = 1.16, 6.58).Conclusions: An active lifestyle throughout childhood and adolescence could prevent obesity development in young adulthood.

The purpose of this study was to examine whether the association between daily light-intensity physical activity (LPA) and total body fat mass changes during childhood. The study sample was 577 children participating in the longitudinal Iowa Bone Development Study. Body fat mass and physical activity (PA) were measured using dual energy X-ray absorptiometry (DXA) and accelerometers, respectively, at approximately 5, 8, and 11 years of age. Age- and gender-specific multivariable linear regression models were fit to predict fat mass by LPA, adjusted for actual age, birth weight, fat-free mass, height, moderate- to vigorous-intensity PA, and physical maturity (only for girls). Among boys, LPA was negatively associated with fat mass at age 11, but not age 5 or 8. Among girls, LPA was negatively associated with fat mass at ages 8 and 11, but not at age 5. LPA may have a beneficial effect against excess adiposity among older children.