You spend eight hours in the office at the computer. Then an hour in the car or on public transport. Then at home, you sit on the couch in front of the TV or with your laptop on your lap. That’s 10-12 hours of sitting daily. This is the norm for millions of Australians. But physiologists call this condition a “sedentary epidemic.” And they warn: chronic sitting ages the body faster than smoking, poor environmental conditions, or even excessive sun exposure. It sounds dramatic, but the research data is inexorable. A 2022 University of Sydney study involving 150,000 people showed that people who sit for more than eight hours a day and don’t compensate with physical activity have a 40% higher risk of premature death from all causes. “Sitting is the new smoking,” said the study’s lead author, Professor Emmanuel Stamatakis.
How does sitting age you? It’s at the cellular level. When you sit, the large muscles of your legs and buttocks (the body’s largest muscles) become inactive. They stop sending signals to the brain and cardiovascular system. Levels of the enzyme lipoprotein lipase, which breaks down fats in the blood, drop. As a result, after just a few hours of sitting, “bad” cholesterol levels rise and insulin sensitivity decreases. This directly leads to type 2 diabetes, obesity, and atherosclerosis. Furthermore, sitting impairs blood flow in the leg vessels, increasing the risk of thrombosis and varicose veins.
But the most interesting aspect is the effect on telomeres. Telomeres are the end sections of chromosomes that shorten with each cell division. The shorter the telomeres, the older the cell and the closer it is to death. A 2023 Swedish study found that people who sit for more than 10 hours a day and are sedentary have telomeres shorter by an average of 8-10 years compared to active peers of the same age. In other words, your biological age could be a decade older than your passport age if you’re a sedentary person. And the sun has nothing to do with it.
The good news: the damage from sitting is reversible. You don’t need to run marathons or buy an expensive treadmill. Just implement three simple rules. They seem small, but when combined, they have a huge impact.
Rule 1: Take a break every 45 minutes. Not two hours without moving, but every 45 minutes—5 minutes of activity. Get up, walk around the office, do 10 squats, jump, and stretch. Research shows that this frequency of breaks completely counteracts the damage from sitting. If you can’t get away from your desk, do exercises while sitting: raise your legs parallel to the floor, tighten your glutes, and rotate your feet.
