Brachial vascular function after acute aerobic exercise in older adults with and without type 2 Diabetes mellitus

Abstract

Brachial vascular function after acute aerobic exercise in older adults with and without type 2 diabetes Purpose: The acute exercise model provides clinical insights regarding vascular dysfunction in adults with type 2 Diabetes Mellitus (T2DM), as it uncovers abnormalities not normally present at rest. However, whether vascular responses to acute exercise in adults with T2DM are intensity-dependent, and whether response patterns differ with aging and disease, remains unknown. Thus, we examined brachial artery flow-mediated dilation (FMD) and flow-mediated slowing (FMS) of pulse wave velocity (PWV), 10 and 60-min after an acute bout of high-intensity interval exercise (HIIE) and moderate-intensity continuous exercise (MICE) in middle-aged and older men with and without T2DM compared to young men without T2DM. Hypothesis: HIIE would induce a larger decrease in FMD immediately after exercise cessation compared to MICE in older men with and without T2DM. Methods: Twelve males with (57-84 yr) and without (57-76 yr) T2DM, and 12 healthy young adults (20-40 yr), completed an isocaloric acute exercise bout of HIIE, MICE, and a non-exercise condition in randomized order. FMD and FMS were evaluated and offline analyzed by the same researcher following standard guidelines. Central and peripheral arterial stiffness were measured via applanation tonometry estimates of carotid-femoral PWV (cfPWV) and carotid dorsalis pedis PWV (cdPWV), respectively. Statistical inferences were performed using linear mixed models. Results: %FMD was reduced (d= - 5.94, 95% CI: -10.50 to -1.38 %, p=0.002), whereas %FMS was increased (d= 4.55, 95% CI: 0.62 to 8.48%, p=0.01), 10-min after HIIE only in older adults with T2DM, returning to resting values 60-min into recovery. Conversely, %FMD was increased (d= 5.33, 95% CI: 0.76 to 9.89%, p=0.009) 10-min after MICE only in older adults with T2DM, while cfPWV and cdPWV remained unchanged following HIIE and MICE in all groups. There were no group differences at rest in brachial %FMD and %FMS, while cfPWV and cdPWV were higher in older adults with T2DM compared to age-matched controls (cfPWV: d= 1.94, 95% CI: 0.44 to 3.44 m. s-1, p=0.009). Conclusions: We found evidence of intensity- and disease-dependent vascular responses to acute aerobic exercise. These findings suggest that high-intensity acute exercise transiently impairs vascular function in older adults with T2DM, which may constitute an important trigger for exercise-based long-term improvements in vascular function. This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.