Many people spend a large part of their day sitting—whether at work, while commuting, or during leisure time. But sitting for long periods isn’t just a harmless habit. It can have harmful effects on our health, especially on the way blood vessels work. This is important because problems with blood vessels can increase the risk of heart disease and other serious conditions.
Researchers already know that sitting for too long can affect blood flow in the legs. But what about the arms or other parts of the body that aren’t directly involved in sitting? There hasn’t been much research on that, so scientists from the University of Tsukuba in Japan decided to look into it.
Their study focused on the forearm, a non-lower-limb area. They wanted to find out if sitting still for more than an hour could harm how blood flows in the skin of the forearm. They also wanted to know whether changing the skin’s temperature—by switching between warming and cooling it—could help reduce any negative effects.
The study involved 11 healthy young adults. Each person sat in a chair for 75 minutes without moving much. During that time, the skin on four areas of their forearms was alternately cooled and heated.
The researchers closely monitored how well the small blood vessels in the skin were functioning, particularly their ability to widen (vasodilation) and narrow (vasoconstriction) as needed to control blood flow.
The results were quite interesting. The scientists found that sitting for 75 minutes reduced the skin’s ability to widen its blood vessels in the forearm. This means that the blood vessels were not as good at helping blood flow through the skin, which could be a sign of early damage or dysfunction.
However, when the skin was regularly warmed and cooled during the sitting period, this problem was reduced. In other words, the heat-and-cold treatment helped protect the small blood vessels from the harmful effects of sitting.
Even though sitting didn’t seem to harm the blood vessels’ ability to narrow (a process called vasoconstriction), the temperature changes still made that function slightly better. This suggests that alternating heat and cold not only prevents harm but might even improve some parts of how the skin’s blood vessels work.
These findings are important because they show that long periods of sitting don’t just affect the legs—they can also reduce healthy blood flow in other parts of the body. More importantly, something as simple as changing the temperature of the skin could help prevent these problems.
In summary, this study shows that prolonged sitting can reduce the ability of the forearm’s small blood vessels to function properly, at least when it comes to widening to let more blood through. However, alternating between warming and cooling the skin during sitting can help reduce or prevent this issue.
This discovery could lead to new ways to protect vascular health—such as using wearable devices or adjusting room temperatures—to help people stay healthier even when they have to sit for long periods.
If you care about heart disease, please read studies that herbal supplements could harm your heart rhythm, and how eating eggs can help reduce heart disease risk.
For more health information, please see recent studies that apple juice could benefit your heart health, and results showing yogurt may help lower the death risks in heart disease.
The research findings can be found in Microvascular Research.
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