A new research published last week in the Journal of Physiology showed 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 five 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.
Both of these changes may have implications for diseases such as heart disease, stroke and diabetes as they are characterized by changes in blood flow control, due to an impaired vascular system.
If this study is replicated in patients with vascular disease, it could indicate whether or not this training method could serve as a new drug-free treatment for improving vascular health and reducing disease risk, especially in people with lower mobility.
Moreover, stretching may also be used during hospitalisation or after surgical interventions, to preserve the vascular health when patients have low mobility. Carers or family members can also perform it at home.
An author on the paper, Emiliano Ce, said this new application of stretching is especially relevant in the current pandemic period of increased confinement to homes, where the possibility of performing beneficial training to improve and prevent heart disease, stroke and other conditions is limited.
Also, another research suggests that exercise can slow or prevent the development of macular degeneration and may benefit other common causes of vision loss, such as glaucoma and diabetic retinopathy.
The new study from the University of Virginia School of Medicine found that exercise reduced the harmful overgrowth of blood vessels in the eyes of lab mice by up to 45 per cent. This tangle of blood vessels is a key contributor to macular degeneration and several other eye diseases.
The study represents the first experimental evidence showing that exercise can reduce the severity of macular degeneration, a leading cause of vision loss, the scientists report. Ten million Americans are estimated to have the condition.
Researcher at the UVA’s Center for Advanced Vision Science, Dr. Bradley Gelfand, said: “There has long been a question about whether maintaining a healthy lifestyle can delay or prevent the development of macular degeneration. The way that question has historically been answered has been by taking surveys of people, asking them what they are eating and how much exercise they are performing.
“That is basically the most sophisticated study that has been done. The problem with that is that people are notoriously bad self-reporters … and that can lead to conclusions that may or not be true. This [study] offers hard evidence from the lab for very first time.”
Enticingly, the research found that the bar for receiving the benefits from exercise was relatively low — more exercise didn’t mean more benefit. “Mice are kind of like people in that they will do a spectrum of exercise. As long as they had a wheel and ran on it, there was a benefit,” Gelfand said. “The benefit that they obtained is saturated at low levels of exercise.”
An initial test comparing mice that voluntarily exercised versus those that did not found that exercise reduced the blood vessel overgrowth by 45 per cent. A second test, to confirm the findings, found a reduction of 32 per cent.
The scientists aren’t certain exactly how exercise is preventing the blood vessel overgrowth. There could be a variety of factors at play, they say, including increased blood flow to the eyes.
Gelfand, of UVA’s Department of Ophthalmology and Department of Biomedical Engineering, noted that the onset of vision loss is often associated with a decrease in exercise. “It is fairly well known that as people’s eyes and vision deteriorate, their tendency to engage in physical activity also goes down,” he said. “It can be a challenging thing to study in older people. … How much of that is one causing the other?”
The researchers already have submitted grant proposals in hopes of obtaining funding to pursue their findings further.
“The next step is to look at how and why this happens, and to see if we can develop a pill or method that will give you the benefits of exercise without having to exercise,” Gelfand said. “We’re talking about a fairly elderly population [of people with macular degeneration], many of whom may not be capable of conducting the type of exercise regimen that may be required to see some kind of benefit.” (He urged people to consult their doctors before beginning any aggressive exercise program.)
Gelfand, a self-described couch potato, disclosed a secret motivation for the research: “One reason I wanted to do this study was sort of selfish. I was hoping to find some reason not to exercise,” he joked. “It turned out exercise really is good for you.”