Fidgeting may be annoying for colleagues but it is good for your arteries, according to research at the University of Missouri.
The research, published in the American Journal of Physiology: Heart and Circulatory Physiology, found that vascular function was improved in those who bounced on their feet.
The researchers measured the level of blood flow, a good indicator of arterial health, in the legs of 11 healthy volunteers.
The subjects were then asked to sit for three hours continuously at a desk. They were instructed to keep one leg completely still, and fidget with the other, by tapping their heel for one minute and then letting it rest for four.
During the three-hour observation period, the researchers monitored the blood flow in the leg arteries. Flow in the static leg declined markedly, but it rose in the fidgeting leg.
After three hours, the researchers tested the ability of the volunteers’ arteries to respond to changes in blood pressure. The artery in the unmoving leg did not respond as well as it had during baseline testing, suggesting that it was no longer as healthy as it had been. In contrast, the artery in the fidgeting leg responded better to changes in blood pressure than it had initially.
Dr Jaume Padilla, who led the study, told the New York Times: ‘We were surprised by the magnitude of the difference between the two legs. We had expected that fidgeting might attenuate the reduction in blood flow and any subsequent acute changes in vessel health, but the differences in terms of blood flow and subsequent arterial function were much more significant than we had anticipated.
‘The muscular contractions associated with fidgeting are really quite small, but it appears that they are sufficient to combat some of the unhealthy consequences of sitting.’
It has long been apparent that those who stand and therefore move more are generally healthier and fitter than those who sit and therefore move less. However, individuals who fidget while sitting can negate some of the harms associated with being sedentary (as suggested here and here). Such small movements burn calories, help control blood sugar and reduce fat stores.
Specifically, this study measured endothelial function. The endothelium is a single layer of cells that lines our entire tree of blood vessels. It helps to control fluid balance, blood pressure and blood clotting.
One measure of endothelial function is flow mediated dilation (FMD), which involves measuring the size of a particular artery, obstructing it for a sustained period and then upon release measuring the percentage increase in diameter. The healthier the artery, and therefore the endothelium, the more it will dilate. That is because there is a greater increase in blood to wash out the waste products, such as acids, carbon dioxide and free radicals.
The differences found were significant, but this was a small study, on 11 young and healthy subjects. The findings would need replicating in larger, older and diseased groups of individuals and followed for a sustained period of time before firm conclusions could be made on the benefits of fidgeting on vascular health.