Studies show excessive sitting has an impact on the brain and body, say Dr. W. Gifford-Jones and Dr. Diana Gifford-Jones. (File photo by The Associated Press)

Studies show excessive sitting has an impact on the brain and body, say Dr. W. Gifford-Jones and Dr. Diana Gifford-Jones. (File photo by The Associated Press)

HEALTH: Stand up to read this week’s column

Get up on your feet. Seriously. It will be good for you.

Sitting is something we have all become accustomed to doing a lot more of lately.

Just prior to the pandemic, studies showed that the average adult spent about 6.5 hours a day sitting – an hour longer than had been the case a decade earlier. In 2019, teenagers were sitting for upwards of eight hours a day, and for some much longer than that.

During the pandemic, a study in the U.K. found that people were spending more than eight hours a day sitting. Canadians are reportedly sitting around for 10 hours a day!

Dr. Jennifer Heisz, associate professor of kinesiology at McMaster University, surveyed over 1,600 people to compare physical activity prior and during the pandemic. She found that aerobic activity was down by about 20 minutes per week, strength training down roughly 30 minutes per week, and sedentary time was up about 30 minutes per day.

Why worry about it? For starters, the Canadian Cancer Society reports “a growing body of evidence supports a link between sedentary behaviour and an increased risk of colorectal cancer.” A German study found people who worked desk jobs or driving vehicles had a 24 per cent increased risk of developing colon cancer as compared to people who don’t sit at work. Every two-hour increase in sitting time was associated with an eight per cent increased risk of colon cancer. Sitting and watching television was far worse, with a 54 per cent increased risk for couch potatoes as compared to those spending less time in front of the TV.

If that’s not bad enough, think again. (By the way, as brain scientists suggest, you’ll be better able to think about this if you are standing up.)

Relaxed muscles absorb less glucose from the blood, increasing the risk of type 2 diabetes. A Norwegian study may be good news for otherwise active people who sit for prolonged periods of time, but not such good news for inactive people. The study found sitting time has little association with diabetes risk in the population as a whole. But among physically inactive people, sitting for five to seven hours a day was associated with a 25 per cent higher risk of diabetes compared with sitting less than four hours a day.

Excessive sitting also has an impact on the brain. Less blood is pumped to this vital organ and even a very small difference in blood flow can impact on memory and create cloudy thinking.

The negative consequences of sitting too much on Alzheimer’s disease is not exactly breaking news. More than a decade ago, The Lancet, Neurology reported, “worldwide, approximately 13 per cent (nearly 4.3 million) AD cases may be attributable to physical inactivity.” Still sitting? Here’s some motivation to get up. The report continued, “A 10 per cent reduction in the prevalence of physical inactivity could potentially prevent more than 380,000 AD cases globally and nearly 90,000 cases in the U.S., while a 25 per cent reduction in physical inactivity prevalence could potentially prevent nearly 1 million AD cases globally and 230,000 in the U.S.”

Dr. Heisz observed a shift in what is motivating people to get up and get active. In her recent study, participants reported less interest in their physical health and appearance and more concern for their mental well-being. That’s a welcome trend.

The message is compelling. Reducing the amount of your sitting time improves the chances for better cardiovascular health, lowers cancer risk, diabetes risk and the prospects for Alzheimer’s. So get up from your chair!

Unless you are 98, says Giff.

Dr. W. Gifford-Jones and Dr. Diana Gifford-Jones can be reached at