Theses and Dissertations

Date of Award


Document Type


Degree Name



Exercise Science

Committee Chair

Joshua L. Keller


Vascular dysfunction is the earliest known marker of neurodegeneration. However, limited research has been conducted to determine if changes in peripheral vascular function track differences in brain health. Therefore, the purpose was to determine if previously reported sex differences in near-infrared spectroscopy (NIRS) vascular occlusion test (VOT) parameters persist across the lifespan and if these differences track age- and sex-related differences in a cognitive task. Ninety-nine healthy, cognitively intact adults (50 women, 49 men) across the adult lifespan (19-81 yrs) were used for analysis. The combination of NIRS-VOT was used to quantify microvascular function. Cognition was defined as the time to completion on Part A and Part B of the trail-making test (TMT). Five, separate 2-way between factor ANOVAs (sex x age) were used to determine mean differences in each NIRS-VOT derived variable and TMT outcome. Regardless of age, men exhibited faster rates of desaturation (p < 0.001; 𝑋̅Δ = 0.031 %Β·s-1) during ischemia and achieved a higher magnitude of total re-saturation (p = 0.006; 𝑋̅Δ = -2.5 %) (StO2max) following ischemia. Independent of sex, StO2max progressively decreased with increased age (p < 0.001; πœ‚π‘2 = 0.274). TMT Part A indicated that men (p < 0.001; πœ‚π‘2 = 0.546) and women (p = 0.020; πœ‚π‘2 = 0.154) exhibited sex specific rates of decline in processing speed, whereas Part B decreased across age independent of sex (p < 0.001; πœ‚π‘2 = 0.188). This was the first study to demonstrate that sex differences in NIRS-VOT outcomes, StO2max and desaturation rate, persist across the adult lifespan.