The relationship between sedentary bout duration and glucose in adults with type 2 diabetes

Physical activity is important for blood glucose management in people with Type 2 diabetes (T2D). Little research has explored the relationship between sedentary behaviour and mean glucose and glucose variability in people with T2D using objective and continuous measurements. Aims: To explore the relationship between sedentary bout duration and mean glucose and glucose variability in people with T2D using objective continuous measurement. Methods: 16 participants with T2D managed with diet, Metformin or DPP4 inhibitors were recruited (mean age 64.1±10.9 yr & BMI 29.4±6.9 kg/m2). Participants completed a demographic questionnaire and wore an activPAL accelerometer and FreeStyle Libre continuous glucose monitor for 3-14 days whilst documenting sleep, food and medication. Average proportion of time spent sitting/lying, during the waking day were calculated. Bouts of wake time sedentary behaviour were identified and defined as a period of at least 30 minutes continuous, uninterrupted sitting/lying during the waking day. Correlation analysis was conducted to investigate the relationships between sedentary bout duration and mean glucose, glucose range and glucose coefficient of variation. Results: On average, participants spent 65% of their day sitting/lying, 76% of sedentary bouts were ≥30minutes and 29% of bouts were ≥60minutes. Mean glucose was negatively (r = -0.08, p <0.01) associated with sedentary bout duration. Glucose range (r =0.47, p <0.001) and glucose coefficient of variation (r = 0.26, p <0.001) both positively correlated with sedentary bout duration. Participant characteristics such as age, gender and BMI appear to influence the relationship between sedentary bout duration and glucose response. Conclusions: Results indicate increased sedentary time leads to improved mean glucose and increased glucose variability.