Cardiovascular reactivity to acute psychological stress in females with normal-weight obesity

Mechanisms driving cardiovascular disease (CVD) in females with normal-weight obesity (NWO; normal body mass index [BMI] and high body fat percent) are unclear. Acute psychological stress appears to promote CVD in some populations, in part by causing repeated increases in blood pressure and vascular dysfunction. The objective of this study was to examine psychological stress as a CVD-promoting mechanism in NWO. We hypothesized that NWO females, compared to normal-weight lean (NWL; normal BMI and low body fat percent) females, would (a) report greater perceived chronic stress, and (b) demonstrate acute increases in hemodynamic parameters and vascular dysfunction following an acute psychological stress task. Apparently healthy female participants (N=31; 18-50 years) with a normal BMI (18.5-24.9 kg/m 2 ) were grouped based on body fat percent (iDXA) as NWL (body fat < 33.0%; n=14) or NWO (body fat ≥33.0%; n=17). All participants completed the Perceived Stress Scale-10 (self-report, possible range: 0-40) and a modified Triers Social Stress Test (TSST; in-lab public speaking and arithmetic task lasting ~10 min). Several hemodynamic and vascular measurements were assessed at baseline, immediately following the TSST, and 90 minutes post-TSST. Peripheral blood pressure, aortic blood pressure, and heart rate were measured using Sphygmacor Xcel (Atcor). Double product was calculated as heart rate × peripheral systolic blood pressure. Pulse wave velocity (PWV) and augmentation index normalized to a heart rate of 75 bpm (AIx@HR75) were collected as indicators of arterial stiffness (Sphygmacor Xcel; Atcor). Endothelial function was measured using flow-mediated dilation (FMD; Logiq P9; GE) and back-end analyses are ongoing (data are forthcoming). Primary analyses consisted of independent samples t-tests and mixed-model ANOVAs (group×time). Body fat percent was 37% higher in NWO versus NWL (p< 0.001). NWO reported significantly higher Perceived Stress Scale-10 scores than NWL (17.9±4.0 vs. 13.5±5.8; p=.016). Across both groups, peripheral systolic blood pressure (+7 mmHg; ptime< 0.001), double product (+330 bpm×mmHg; ptime=0.015), and PWV (+0.1 m/s; ptime=0.050) increased following the TSST. Conversely, AIx@HR75 (-4%; ptime=0.025) decreased after psychological stress. Heart rate and peripheral and aortic diastolic blood pressure were unaffected by the stress task (ptime>0.180). Throughout the in-laboratory assessment, heart rate was significantly higher in NWO versus NWL (+6 bpm; pgroup=0.029). No other group main effects were noted (pgroup≥0.149). Group×time interaction effects were also non-significant (pgroup×time≥0.052). In conclusion, NWO females reported higher perceived chronic stress compared to NWL females. Preliminary results suggest this higher chronic stress does not translate to an adverse cardiovascular response to acute, in-laboratory psychological stress. Funding Sources. Internal Funding Sources at Ball State University. This abstract was presented at the American Physiology Summit 2026 and is only available in HTML format. There is no downloadable file or PDF version. The Physiology editorial board was not involved in the peer review process.