598-P: No Relationship between Sedentary Behavior Patterns and Peak Oxygen Consumption (VO2peak) among Overweight Individuals With and Without Type 2 Diabetes

Background: Sedentary behavior (SB) has negative effects on health, even in the context of achieving physical activity (PA) guidelines. It is unclear how total volume and patterns of accumulation of SB may vary among overweight/obese adults with and without uncomplicated type 2 diabetes (T2D) and whether SB is related to aerobic capacity. Purpose: To examine SB patterns and their relationship to estimated peak oxygen consumption (VO2peak) among adults with uncomplicated T2D and overweight controls. Methods: This was a secondary analysis of baseline data from VA-MIXED (NCT03419195), a trial in physically inactive, overweight/obese adults aged 30-55 with and without T2D. Daily pattern of PA/SB was assessed via activPAL for 7 days. Participants completed a cycle ergometer graded exercise test to measure maximal workload. VO2peak was estimated using the American College of Sports Medicine metabolic equation. Pearson correlation, two-sample t-tests, and multiple linear regression analyses were used to examine relationships between variables overall and by T2D status. Results: Baseline data were available for 21 participants (8 T2D, 13 overweight controls), mean (SD) age 43.3 (7.6) yrs, BMI 34.6 (5.6) kg/m2. Participants were sedentary (11.7 [2.2] h/day). There were no differences in step count; stepping, standing, or sedentary time; sit-to-stand transitions, and time in SB bouts ≥1 hour by T2D status (all p>0.11). Correlations between SB variables and VO2peak were not significant (all p>0.20). The relationship between total SB and VO2peak did not change when T2D status was included in the model (β −2.22, p=0.39). Discussion: Objectively measured SB patterns were similar between overweight controls and adults with uncomplicated T2D and did not correlate with VO2peak. Future studies should examine these variables in larger cohorts and evaluate if SB patterns are associated with variability in response to exercise.