Stand up to read this week’s column

BY W. GIFFORD- JONES MD & DIANA GIFFORD-JONES

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 8 hours a day, and for some much longer than that.

During the pandemic, a study in the UK 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% 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 8% increased risk of colon cancer. Sitting and watching television was far worse, with a 54% 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. Among physically inactive people, sitting for 5-7 hours a day was associated with a 25% 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 consequence 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% (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% reduction in the prevalence of physical inactivity could potentially prevent more than 380,000 AD cases globally and nearly 90,000 cases in the US, while a 25% reduction in physical inactivity prevalence could potentially prevent nearly 1 million AD cases globally and 230,000 in the US.”

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 of course, you are 98!