From Our 2011 Archives
Sitting for Too Long Is Bad for Your Health
Taking Even Short Breaks From Sitting Is Good for Your Heart, Waist
By Siobhan Harris
Reviewed by Keith Barnard, MD
Jan. 12, 2011 -- We all know that regular exercise is good for our health and too much sitting isn't ideal. Now a new study suggests it's not just the length of time we spend sitting down but the number of times we get up during that time that can influence our health.
The study, published online in the European Heart Journal, examined the total length of time people spent sitting down and breaks taken in that time, together with various indicators of risk for heart disease, metabolic diseases such as diabetes, and inflammatory processes that can play a role in the blocking of arteries.
It suggests that plenty of breaks, even if they are as short as one minute, seem to be beneficial.
Take a Break to Slim Your Waist
The Australian research found that long periods of sitting down, even in people who did a lot of exercise otherwise, were associated with worse indicators of cardio-metabolic function and inflammation, such as larger waist circumferences, lower levels of HDL ("good") cholesterol, and higher levels of C-reactive protein (an important marker of inflammation) and triglycerides (blood fats).
However, the study also found that even in people who spent a long time sitting down, the more breaks they took during this time, the smaller their waists and the lower the levels of C-reactive protein.
Genevieve Healy, MD, from the University of Queensland led the study.
"The most significant differences were observed for waist circumference," she says. "The top 25% of people who took the most breaks had, on average, a 4.1 cm smaller waist circumference than those in the lowest 25%."
The dangers of being too big around the middle are well-documented.
According to the National Heart, Lung, and Blood Institute, high-risk waist circumferences are:
Healy and her colleagues analyzed earlier U.S. data from nearly 5,000 people aged 20 and over.
The participants wore a small device called an accelerometer, which monitored the amount and intensity of walking or running.
It gave researchers information on sedentary time and breaks in sedentary time.
Small Changes Help
"The potential adverse health impact of prolonged sitting (which is something that we do on average for more than half of our day), is only just being realized," Healy says. "Our research highlights the importance of considering prolonged sedentary time as a distinct health risk behavior that warrants explicit advice in future public health guidelines."
The study suggests even small changes could help, like standing up to take phone calls, walking to see a colleague rather than phoning or emailing, and centralizing trash cans and printers so you have to walk to them.
Amy Thompson, Senior Cardiac Nurse at the British Heart Foundation, says in a statement, "This study was a very interesting read and adds to well established evidence that long periods of inactivity are not good for the heart.
"If you're sitting for long periods it's really important you take regular breaks by getting up on your feet. Regular physical activity is essential to protect cardiovascular health."
SOURCES: Healy, G. European Heart Journal, published online Jan. 11, 2011.News release, European Heart Journal.British Heart Foundation.NHS Choices.National Heart, Lung, and Blood Institute Obesity Education Initiative: "The Practical Guide: Identification, Evaluation, and Treatment of Overweight and Obesity in Adults."