No more Netflix binging…
It’s long been known that being a couch potato could contribute to health-related problems like excessive weight gain, but now researchers warn that the lazy habit may be linked to a smaller brain size later in life.
The study, published in the February 2016 online issue of the journal Neurology, looked at nearly 1,600 adults who were enrolled in the Framingham Heart Study. The adults were an average of 40 years old without dementia or heart disease, and they took a treadmill test at the beginning of the study and then another one two decades later.
"We found a direct correlation in our study between poor fitness and brain volume decades later, which indicates accelerated brain aging," study author Nicole Spartano of the Boston University School of Medicine said in a press release.
On average, the study participants had an estimated exercise capacity of 39 mL/kg/min, which is expressed as the maximum amount of oxygen the body is capable of using in one minute, or peak VO2. Exercise capacity was estimated using the length of time an individual was able to exercise on the treadmill before his or her heart rate reached a certain level.
The results showed that for every eight units lower a person performed on the treadmill test, their brain volume was measurably smaller two decades later. The difference was equivalent to two years of accelerated brain aging!
The researchers also analyzed the results after excluding some participants who either developed heart disease during the study’s course or started taking beta blockers to control blood pressure or heart problems — this group had 1,094 people. After they were excluded, every eight units of lower physical performance was associated with a reduced brain volume equal to one year of accelerated brain aging.
Further, the results showed that the people whose heart rate and blood pressure went up to higher rates during exercise were also more likely to have smaller brain volumes two decades later. According to Spartano, people with poor physical fitness often have higher heart rate and blood pressure responses to low levels of exercise compared to those who maintain better fitness.
"While not yet studied on a large scale, these results suggest that fitness in middle age may be particularly important for the many millions of people around the world who already have evidence of heart disease," she said.
So unfortunately, being a couch potato may be relaxing, but it’s not the best idea when it comes to keeping our bodies and brains as healthy as possible. Vegging out with some popcorn and a movie is fine every once in awhile, but it’s important to make sure you get up off that couch to make time for exercise!
This study was supported by the National Institutes of Health, the American Heart Association, and the National Heart, Lung and Blood Institute.