Increased physical activity is associated with faster gastric emptying in people with overweight or obesity at high risk of type 2 diabetes

INTRODUCTION: Gastric emptying is essential for the control of blood glucose and appetite in response to a meal. Acute exercise decelerates gastric emptying in an intensity-dependent manner and cross-sectional studies have observed faster gastric emptying in physically active compared to physically inactive individuals. However, the impact of changes in physical activity level on gastric emptying in individuals at high risk of type 2 diabetes is poorly understood.

METHODS: This posthoc analysis includes a subsample of 32 participants from the RESET study in which 100 men and women with BMI ≥25 kg/m2 and prediabetes (HbA1c 39-47) or BMI ≥30 kg/m2 were randomized to 3 months of either 1) time-restricted eating (TRE, n=13) or 2) habitual living (control group, n=19). During TRE participants were instructed to consume all foods and beverages (except water) within 10 hours/day. At baseline and after 3 months of intervention, participants ingested a standardized mixed meal followed by a wireless motility capsule (SmartPillTM, Medtronic) to measure gastric emptying time (GET). Physical activity was measured using accelerometers (Axivity AX3) for 7 days at baseline and after 3 months. Associations between changes in physical activity (total physical activity, sedentary time, and physical activity at low-light, high-light, moderate, and moderate-to-vigorous intensity) and changes in GET were assessed using linear regression analysis adjusted for age and sex.

RESULTS: 18 women and 14 men were included in the analysis. Mean (SD) GET at baseline was 292 (74) min. For each hour increase in total physical activity, GET decreased by 0.41 hour (95%CI: -0.60; -0.22) (p˂0.001) and for each additional hour spent on high-light intensity physical activity, GET decreased by -0.62 hour (-1.00; -0.26) (p˂0.001). Per one hour increase in sedentary time, GET increased by 0.41 hour (0.08; 0.74) (p=0.015). No significant associations were observed between changes in physical activity at low-light, moderate, or moderate-to-vigorous intensity and changes in GET.

CONCLUSION: Our results suggest that increased total physical activity and high-light intensity physical activity are associated with a shortening of GET, whereas increased time spent sedentary is associated with prolonged GET in individuals at high risk of type 2 diabetes. Future randomized controlled trials should investigate whether increased physical activity at different intensities affect GET and appetite.

Keywords: Overweight, obesity, prediabetes, gastric emptying, physical activity