A Developmental Model Studying Blood Glucose Variability When Active Young Adults Assume An Obesogenic Lifestyle

The U.S. young adult population commonly regresses into a sedentary lifestyle upon entering the workforce with added sugar consumption. These lifestyle factors lead young adults increased cardiometabolic risks. Limited ecologically relevant models have been developed to assess this transition. PURPOSE: This study aimed to determine if transitioning young adults to an obesogenic lifestyle model (OLM; ~5,000 steps/day + ~180 grams of add-sugar consumption) increases insulin resistance after 10 days. METHODS: Ten recreationally active men (age: 21 ± 1 years; BMI: 25.4 ± 1.3 kg·m-1; VO2peak: 44.0 ± 5.3 ml·kg-1·min-1) were randomized into three groups: Active control (n = 3), sedentary control (n = 3; <5,000 steps·day-1), and OLM (n = 4). 24 h Continuous glucose monitors measured 24 h mean glucose and blood glucose control via blood glucose variability (BGV) measures over the 10-day intervention period. BGV was measured using the standard deviation of 24 h glucose, the 24 h coefficient of variation, and the mean amplitude of glycemic excursions (MAGE). Accelerometers measured daily step counts throughout the 10-day intervention. Fasting plasma insulin was measured and the change in homeostatic model assessment 2 (HOMA2IR) assessed insulin resistance. RESULTS: OLM and sedentary intervention reduced step counts compared to the active group (OLM = 6,142 ± 2,725 steps/day, Sedentary = 4,709 ± 1,754 steps/day, Active = 13,211 ± 6,318 steps/day, respectively; p < 0.05). The OLM increased 24 h mean glucose (OLM = 7.35 ± 0.34 mmol/L, Sedentary = 7.1 ± 0.4 mmol/L, Active = 6.44 ± 0.16 mmol/L). However, additional data is needed to determine whether the OLM increases BGV measures such as standard deviation of 24 h glucose (OLM = 0.97 ± 0.25 mmol/L, Sedentary = 0.86 ± 0.12 mmol/L, Active = 0.72 ± 0.09 mmol/L; p = 0.245), coefficient of variation (OLM = 13.13 ± 2.69 %, Sedentary = 12.3 ± 2.5 %, Active = 11.11 ± 1.15 %, p = 0.549) and MAGE (OLM = 2.56 ± 0.68 mmol/L, Sedentary = 2.3 ± 0.7 mmol/L, Active = 1.74 ± 0.36, p = 0.270). Our preliminary results hint that our OLM intervention may provide an acute increase ΔHOMA2IR (OLM = 0.73 ± 0.8 mmol/L, Sedentary = 0.40 ± 0.40 mmol/L, Active = 0.12 ± 0.26 mmol/L, p = 0.439). CONCLUSION: In a small sample, we report that a 10-day OLM intervention increases 24 h mean blood glucose. Further, data is needed to assess increased BGV.