Active Time Improves Youth Cardiometabolic Measures
(HealthDay News) – The more time children spend engaged in moderate to vigorous physical activity (MVPA), the better their cardiometabolic risk factors, including measures of cholesterol, blood pressure, and waist size, regardless of the amount of time spent sedentary, according to a study published in the Feb. 15 issue of the Journal of the American Medical Association.
Ulf Ekelund, PhD, of the Institute of Metabolic Science in Cambridge, UK, and colleagues analyzed data for 20,871 children (aged 4–18 years) from the International Children's Accelerometry Database. Time spent in MVPA and sedentary time were measured using accelerometry after reanalyzing raw data. Meta-analysis was performed to examine the independent associations between time spent in MVPA and sedentary time and outcomes. Participants were stratified according to tertiles of MVPA and sedentary time.
The researchers found the mean times accumulated by children in MVPA and being sedentary to be 30 and 354 minutes per day, respectively. Time in MVPA was significantly linked with all cardiometabolic outcomes, independent of sex, age, monitor wear time, time spent sedentary, and waist circumference (when not the outcome). Sedentary time was not linked with any outcome independent of time in MVPA. In the combined analyses, higher levels of MVPA were associated with better cardiometabolic risk factors across tertiles of sedentary time. Greater differences in outcomes between higher and lower MVPA were observed with less sedentary time. Those in the top tertile of MVPA accumulated >35 minutes per day at this intensity level, compared with <18 minutes per day for those in the bottom tertile. At 2.1 years of follow-up (in prospective analyses of 6,413 participants), MVPA and sedentary time were not associated with waist circumference, but a higher waist circumference measured at baseline was associated with higher amounts of sedentary time at follow-up.
"Higher MVPA time by children and adolescents was associated with better cardiometabolic risk factors regardless of the amount of sedentary time," the authors write.