30th Jan 2024

The combination of movement behaviours (MB) that occur during waking hours (i.e. sedentary behaviour and physical activity) have been shown to relate to cardiometabolic health (CH) indicators. However, most research focuses on the relationship of individual behaviours, neglecting how different compositions of MB throughout the day associate with CH. The aim of this study was to explore the optimal time spent engaging in sedentary behaviour (SB), light physical activity (LPA), and moderate-to-vigorous physical activity (MVPA) for CH in children and adolescents.

The study used data from the International Children’s Accelerometry Database. Average time spent in SB, LPA and MVPA was measured using accelerometers. Nine CH indicators were assessed via blood samples (LDL and HDL, triglycerides, glucose, insulin), anthropometric measures (waist circumference, BMI), and automatic blood pressure monitors (systolic and diastolic), which were regressed against the time-use composition, adjusting for sex, age, fruit and vegetable intake, soft drink intake and household income. The models were used to estimate the optimal MB time-use composition associated with 5% best CH indicators (i.e. “Goldilocks Day”).

The compositional mean among all participants (n= 1,310; female= 55.9%; age= 11.1±2.5) consisted of 328 minutes SB, 383 minutes LPA and 47 minutes MVPA. Significant relationships were found between the MB time-use composition and all outcomes, excluding LDL cholesterol. For indicators of lipid and glucose metabolism, blood pressure and BMI, the Goldilocks Day consisted of less LPA and more MVPA, when compared to the overall compositional mean. For one indicator, HDL cholesterol, the Goldilocks Day consisted of more LPA and less MVPA.

Optimising time spent engaging in different MB can be an important way of preventing indicators related to increased risk of poorer CH. Public health guidance needs to take this into consideration when developing future recommendations.