0218 Can Physical Activity Mitigate the Adverse Cardiometabolic Health Consequences of Habitual Short Sleep Duration?

Abstract Introduction Insufficient sleep increases obesity and diabetes risk, yet effective interventions to reduce this risk remain limited. Results from short-term experimental sleep restriction suggest physical activity may mitigate these adverse effects of sleep loss. However, it remains unclear if physical activity similarly mitigates risk among individuals with habitual insufficient sleep. Thus, we examined whether moderate-to-vigorous physical activity (MVPA) is associated with insulin sensitivity status in adults with insufficient sleep, and whether MVPA provides explanatory value beyond body mass index (BMI). This preliminary cross-sectional analysis leveraged data from two ongoing studies in adults with insufficient sleep and normal BMI (study A) or overweight/obese BMI (study B). Methods Participants in both studies reported habitual sleep 6.5h/night; study A (n=24, age 23.4±4.4y, BMI=22.1±2.1kg/m2); study B (n=10, age 34.0±7.0y, BMI=29.3±3.1kg/m2). Across two weeks, MVPA was measured using ActivPAL™ devices and total sleep time (TST) was assessed by wrist-actigraphy. Insulin sensitivity was evaluated using Matsuda Index from oral glucose tolerance testing in study A, and glucose infusion rate/kg of body weight (GIR) from hyperinsulinemic–euglycemic clamps in study B. Using established thresholds, participants in both studies were classified as either insulin “sensitive” or “resistant”. Results Insulin sensitivity status differed with 76.9% in study A classified as “sensitive” versus 33.3% in study B (χ²(1)=5.64, p=0.018). MVPA was higher (p=0.03) in A (38.2±21.1min/day) versus B (23.1±14.6min/day). Using logistic regression, BMI, but not MVPA, significantly predicted insulin sensitivity status (BMI: OR=1.45, 95% CI:1.11–2.19 p=0.024). Furthermore, after adding MVPA, BMI remained significant (OR=1.32, 95% CI:1.05–1.85, p=0.049), and model fit was not significantly altered (p=0.77, Likelihood Ratio Test), indicating MVPA did not significantly attenuate the BMI-insulin sensitivity status association. Conclusion Among adults with habitual insufficient sleep, BMI was the strongest determinant of insulin sensitivity status, whereas MVPA did not independently predict insulin sensitivity status. Differences between study groups highlight variability in metabolic risk, suggesting individuals with insufficient sleep and higher BMI may face greater cardiometabolic vulnerability that MVPA alone may not counteract. Future research using randomized controlled trials is needed to confirm these observational analyses. Support (if any) NIH-R01HL178934, NIH-UL1TR002538; NIH-K01HL145099; NIH-R01HL166733; NIH-T32DK110966; Ben B. and Iris M. Margolis Foundation