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Background: Older adults spend a significant portion of their day sedentary, leading to declines in vascular health. Passive interventions, such as passive leg movement (PLM) and passive leg stretching (PLS), may offer a practical solution for mitigating sitting-induced vascular dysfunction. Purpose: To evaluate the effects of PLM and two PLS modalities, prolonged stretching (PS) and intermittent stretching (IS), on vascular function following 2.5 hours of sitting in healthy older adults. Methods: Seven older adults (70.9 ± 4.2 years) completed four conditions: control (CON), PLM, PS, and IS. Measures included popliteal artery flow-mediated dilation (FMD), pulse wave velocity (PWV), common femoral artery blood flow and shear rate, and microvascular oxygenation using near-infrared spectroscopy (NIRS). Hemodynamic and vascular responses were assessed pre- and post-sitting, with additional assessments immediately before and after the intervention. Results: FMD declined significantly post-sitting in CON (p = 0.015) but was preserved in PLM, PS, and IS, with IS showing a trend toward improvement. Blood flow and shear rate significantly declined in CON (p = 0.0001 and p = 0.0056, respectively), but were preserved in PLM and IS. Both PLM and IS produced significant increases in blood flow and shear rate immediately post-intervention. PWV and microvascular oxygenation measures were unchanged across conditions, although IS showed favorable trends in microvascular responses. Conclusion: PLM and IS effectively preserved vascular function and improved acute hemodynamic responses in older adults during prolonged sitting. These passive strategies may serve as viable interventions to counteract sedentary behavior in populations at risk for vascular decline.