Studies have made quite clear in recent years just how important frequent exercise is for reducing the risk of many common modern-day maladies — from high blood cholesterol, to diabetes, to memory and cognition impairments and even some cancers.
We’ve also learned that sedentary lifestyles, where so many of us sit at a desk or in front of a computer for many hours each day, can hurt our health in the long run. Studies have found that even for people who get plenty of vigorous, frequent exercise, sitting for hours at a time cuts their life expectancy by years.
A study published in 2012 found that people who sit for three hours straight a day reduce their life expectancy by two years; other studies found that a person who sits for six hours a day cuts their life expectancy by 20 percent, compared to people who sit for three hours or less.
So, the longer we sit, the worse it is for our health, even when we get regular exercise.
But a new study has found that periodically taking even five minutes to walk around, get the blood circulating, during long sitting periods, seems to offset the damage that sitting for hours does to our blood vessels.
Researchers at Indiana University measured the function of the femoral artery (in the thigh) in 11 healthy males aged 20 to 35, who were not obese. The study involved two parts. For the first part, the men sat for three hours without moving their legs. Researchers then used a blood pressure cuff and ultrasound technology to measure femoral artery function.
For the second part, the men again sat for three hours without moving the legs, except they also walked on a treadmill at a slow speed of 2 miles per hour, for five minutes, 30 minutes after the sitting period started, then 1.5 hours after, and 2.5 hours after.
The results: In the first part of the study, the researchers found that sitting for just one hour reduced expansion of the femoral arteries by as much as 50 percent. But when the men walked for five minutes for every hour that they sat, there was no reduction in artery expansion.
Background information supplied by the university stated that sitting for long periods can cause blood to pool in the legs; this happens because muscles aren’t contracting and pumping blood to the heart as much as when a person is engaged in physical activity.
The study’s lead author went on to say that endothelial cell function can be impaired over time as a result of diminished blood-pumping activity (the endothelium is the thin layer of cells that lines the inside of blood vessels), and that reduced endothelial cell function is an early marker of cardiovascular disease.
It appears from this study that just like muscles, including our heart, get stronger and healthier through physical activity, our veins, which work in unison with our muscles, can stay stronger and healthier when we cause more blood to be pumped into them.
Health researchers have previously advocated for more workplace opportunities for employees to engage in periodic physical activity when their work involves sitting at a desk for hours. It is good to know that that activity does not have to be rigorous or long, to be beneficial.
By Lisa Pecos