For very obese people, standing up is a good start

"These findings indicate the importance of investigating sedentary behavior as a distinct health risk," says Wendy C. King. (Credit: Dan Phiffer/Flickr)

For adults who are severely obese, the more sedentary they are, the higher their risk for diabetes and other health problems—regardless of how much exercise they get.

Researchers say the findings could be used to design and test programs that emphasize reducing time spent sitting, rather than immediately working toward increased physical activity or exercise, such as brisk walking.

“Adults with severe obesity often have difficultly following national guidelines to participate in at least 30 minutes per day of moderate- to vigorous-intensity physical activity for health benefits,” says lead author Wendy C. King, associate professor of epidemiology at the University of Pittsburgh.

“Our findings suggest that replacing sedentary behavior, like watching television or sitting at the computer, with low-intensity physical activities, such as light housework or going for a casual stroll, may improve cardiometabolic health in this population.”

[Can a 10-minute walk erase 6 hours of sitting?]

Defining “sedentary time” as 10 minutes or more without walking yielded stronger associations between sedentary behavior and cardiometabolic health compared to allowing sedentary time to be as short as one minute, which has been the norm in the field.

“This is important because accurate assessment of sedentary behavior is crucial to being able to evaluate if and how this behavior is related to health outcomes. If our estimate of sedentary behavior is poor, we may not detect true associations,” King says.

King and colleagues followed 927 patients participating in the Longitudinal Assessment of Bariatric Surgery-2 , a prospective study of patients undergoing weight-loss surgery at one of 10 different hospitals across the US. For a one-week period before surgery, the research team measured the participants’ activity—or lack of activity—using monitors that tracked the number of steps taken each minute.

[Two-thirds of U.S. adults are overweight or obese]

For every hour per day participants spent in sedentary bouts of at least 10 minutes, their odds of having diabetes increased by 15 percent, metabolic syndrome by 12 percent, and elevated blood pressure by 14 percent, and their waist circumference was a half inch larger, after adjusting for their sex, age, household income, smoking status, alcohol use, depressive symptoms, body mass index (BMI), and time spent in moderate- to vigorous-intensity physical activity.

“These findings indicate the importance of investigating sedentary behavior as a distinct health risk behavior, not simply lack of moderate- to vigorous-intensity physical activity, among adults with severe obesity,” King says. “This ultimately may inform physical activity guidelines for this special population.”

Future research is needed to determine whether replacing sedentary behavior with low-intensity physical activity is an effective approach to preventing and managing cardiovascular and metabolic diseases in adults with severe obesity, and evaluate strategies to help this population make such lifestyle changes.

Other researchers from the University of Pittsburgh and from Weill Cornell Medical College, the University of Washington, the Neuropsychiatric Research Institute, Oregon Health and Science University, and Mount Sinai Hospital in New York are coauthors of the study. The National Institutes of Health’s National Institute of Diabetes and Digestive and Kidney Disease funded the work, which appears in Preventive Medicine.

Source: University of Pittsburgh