New research published in the Journal of Physiologyshows that 12 weeks of easy-to-administer passive stretching helps improve blood flow by making it easier for your arteries to dilate and decreasing their stiffness.
Passive stretching differs from active stretching in that the former involves an external force (another person or gravity) stretching you, whereas active stretching is performed on your own. The changes they observed in blood vessels could have implications for diseases, including the number one global killer, heart disease.
Researchers at the University of Milan assigned 39 healthy participants of both sexes to two groups. The control group didn't undergo any stretching. The experimental group performed leg stretches 5 times a week for 12 weeks. Researchers evaluated the effect of passive stretching on the blood flow locally and in the upper arm. They found that the arteries in both the lower leg and upper arm had increased blood flow and dilation when stimulated, along with decreased stiffness.