Abstract
AIMS: Little is known about how the alignment between daily behaviours, such as physical activity and eating, and chronotype relates to glucose metabolism. We investigated whether alignment of physical activity and meal timing with chronotype was associated with glycaemic parameters and with prediabetes or type 2 diabetes (T2DM). MATERIALS AND METHODS: In a cross-sectional analysis of 1384 participants from The Maastricht Study, we examined associations between behaviour-chronotype alignment and glucose metabolism. Physical activity timing was assessed by accelerometry and defined as the daypart with the highest step count. Meal timing, from a chrono-nutrition questionnaire, was defined as the daypart with the most eating occasions. Chronotype was estimated using the midpoint of sleep on free days corrected for sleep debt. Alignment reflected concordance between behaviour timing and chronotype. Confounder-adjusted logistic and linear regression models estimated associations with (pre)diabetes and with log-transformed fasting plasma glucose (FPG), 2-h post-load glucose (2hPLG), and haemoglobin A1c (HbA1c). RESULTS: Weekday alignment of physical activity timing with chronotype was associated with lower HbA1c (β per 20% more aligned weekdays: -0.48%, 95% CI -0.95, -0.02). Weekday meal timing alignment was associated with lower odds of prediabetes or T2DM (OR aligned vs. misaligned: 0.62, 95% CI 0.43-0.89). No significant associations were observed for weekend alignment, for FPG or 2hPLG, or for interactions between activity and meal timing alignment. CONCLUSIONS: Weekday, but not weekend, alignment of physical activity and meal timing with chronotype was modestly associated with more favourable glucose metabolism. These findings suggest a potential role of behaviour-chronotype alignment in metabolic health, warranting confirmation in prospective and intervention studies.