Associations of Moderate-to-Vigorous Physical Activity Timing with Type 2 Diabetes Incidence in UK Biobank and Prevalent Glycemic measures in NHANES

Objective: We assessed the association between timing of moderate-to-vigorous physical activity (MVPA) with incident Type 2 Diabetes (T2D) and glycemic measures. Research design and methods: Using regression models, associations were assessed between accelerometer-derived MVPA timing and incident T2D in UK Biobank (UKB) (N=84,528, prospective), prevalent diabetes and glycemic measures in National Health and Nutrition Examination Survey (NHANES) (N=6,998, cross-sectional). Results: In UKB, with early morning (05:00–9:59) MVPA as reference and before adjustment for total MVPA, “variable-timing” MVPA was associated with lowest incident T2D risk; while after adjustment, afternoon-evening MVPA (15:00–24:00) showed the lowest incident T2D risk. In NHANES, afternoon/early evening MVPA were weakly associated with more favorable glycemic measures and lower diabetes prevalence after adjustment for total MVPA. Conclusions: When keeping total MVPA volume constant, clustering MVPA in the afternoon-evening was associated with the strongest reduction in incident T2D risk, fewer prevalent diabetes and more favorable glycemic measures.