Physical Activity and Sedentary Behaviour Clustering: Segmentation to Optimise Active Lifestyles.

Background: Increasingly the health impacts of physical inactivity are being distinguished from those of sedentary behaviour. Nevertheless, deleterious health prognoses occur when these behaviours combine, making it a Public Health priority to establish the numbers and salient identifying factors of people who live with this injurious combination. Method: Using an observational between-subjects design, a non-probability sample of 22,836 participants provided data on total daily activity. A 2-step hierarchical cluster analysis identified the optimal number of clusters and the subset of distinguishing variables. Univariate analyses assessed significant cluster differences. Results: High levels of sitting clustered with low physical activity. The ‘Ambulatory & Active’ cluster (n=6,254) sat for 2.5 to 5 h d-1 and were highly active. They were significantly younger, included a greater proportion of males and reported low Indices of Multiple Deprivation compared to other clusters. Conversely, the ‘Sedentary & Low Active’ cluster (n=6,286) achieved ≤60 MET.min.wk-1 of physical activity and sat for ≥8 h d-1. They were the oldest cluster, housed the largest proportion of females and reported moderate Indices of Multiple Deprivation. Conclusions: Public Health systems may benefit from developing policy and interventions that do more to limit sedentary behaviour and encourage light intensity activity in its place.

http://dx.doi.org/10.1123/jpah.2015-0307