This study was aimed at evaluating the effect of a tailored exercise intervention programme in the Arterial Stiffness (AS) of old adults. Methods: Non-randomized intervention study, enrolling 32 community dwelling old adults, aged over 65 years (mean age: 83.28 ± 8.29 years), with no prior history of major cardiovascular events. Participants were divided into two groups (intervention group-Group 2, and control group-Group 1) according to their willingness to participate in the physical training program. The exercise program included aerobic and strength components, prescribed in a personalized approach, and implemented under direct control of two experienced professionals. Aortic Pulse Wave Velocity (PWV), a measure of AS, was evaluated at baseline and 3-months after the intervention period. Clinical evaluation, anthropometric measures and blood samples were also collected in both time-points. Results: The groups had similar clinical and demographic characteristics at baseline. After the intervention program, a significant reduction in PWV was observed only in Group 2 [F(1, 15) = 29.38; p < 0.001; η 2 = 0.67]. A readjustment of the PWV age-dependent trajectory was observed, with a reduction of the absolute PWV in all age strata. A significant reduction in systolic brachial blood pressure was also depicted in Group 2 [mean difference: 12.57 mmHg; F(1, 15) = 9.46; p = 0.01; η 2 = 0.39]. Parameters related to functional status, such as the handgrip strength, the self-efficacy for exercise and the activity and participation profile, were also significantly improved in Group 2. Conclusion: Physical exercise was shown to be an effective non-pharmacological tool to positively modulate age-related decline in AS in older adults.