A new study reveals that sitting for long hours each day can harm even young, active people, increasing the risk of heart problems and obesity.
Researchers found that spending 8 or more hours sitting daily raises cholesterol levels and body fat, even if someone exercises regularly. The study suggests current exercise guidelines may not be enough to protect against the effects of prolonged sitting.
Most research on this topic focuses on older adults, but this study looked at younger people, with an average age of 33.
Researchers from UC Riverside and the University of Colorado, Boulder, studied over 1,000 men and women in Colorado.
Their findings, published in PLOS One, show that too much sitting can have serious health consequences.
Sitting for long hours increases cholesterol ratios (a measure of heart disease risk) and BMI (body fat measure).
These changes are early warning signs for more severe health problems later in life. For example, sitting all day can raise BMI by almost one full point compared to those who sit only a few hours daily.
Lead researcher Ryan Bruellman explained that this increase in BMI was due solely to sitting, not diet or smoking.
For men in their early 30s and women in their mid-30s, prolonged sitting also pushed cholesterol ratios into a higher-risk range. This means even people who already had healthy cholesterol levels saw their risk for heart disease increase.
Current U.S. health guidelines recommend 2.5 hours of moderate exercise or 1 hour and 15 minutes of vigorous exercise each week.
But the study found these amounts are not enough to counteract the effects of sitting all day. To lower the risks, researchers recommend doubling the amount of weekly exercise to 5 hours of moderate activity or 2.5 hours of vigorous activity.
For people with sedentary jobs or lifestyles, adding short bursts of vigorous exercise can make a difference. Even 10 minutes of intense activity for every extra hour of sitting significantly improves health outcomes.
The study also looked at identical twins to see if genetics played a role. Among twin pairs, those who sat less or exercised more had healthier BMI and cholesterol levels than their siblings who sat longer. This shows that lifestyle choices are key to better health.
The takeaway? Move more and sit less. If reducing sitting time isn’t possible, aim to exercise harder and longer. “Young adulthood is the best time to build healthy habits,” Bruellman said. “Get up and move—it’s never too early to start.”
Source: UC Riverside.
