Short bursts of light intensity physical activity like climbing stairs or doing housework can help improve fitness levels of people who are obese, Canadian researchers say.

Scientists at Queen's University in Kingston, Ont., measured the duration and intensity of these sorts of movements and tested cardio-respiratory fitness levels of 43 men and 92 women who were inactive and abdominally obese.

The intensity of the activity seems to be particularly important, with a cumulative 30-minute increase in moderate physical activity throughout the day offering fitness benefits, the researchers reported in Medicine & Science in Sports & Exercise, the journal of the American College of Sports Medicine.

"These findings are important because many people do not perform the types of physical activity typically recommended for health benefit (such as 30 minutes per day of structured activity that raises your heart rate) or do not like to perform structured physical activity," Ashlee McGuire, the study's lead researcher and a graduate student at the School of Kinesiology and Health Studies, said in an email Tuesday.

"Encouraging these individuals to perform the incidental physical activity is a favourable alternative that may result in positive health changes without requiring a large time commitment or performing fatiguing physical activity."

McGuire and her co-author, kinesiology Prof. Robert Ross, define incidental physical activities as non-purposeful physical activity accrued through activities of daily living, such as doing housework, climbing stairs or walking around the office.

The main message is that performing these types of activities may benefit your health, said McGuire, who said she can't sit or stay still for very long.

The researchers were quick to point out that more physical activity is better.

In the study, participants wore an accelerometer on their right hip for a week to measure how long and how intensely they moved.

The average accelerometer counts values that the researchers observed were equivalent to that of walking at a slow, leisurely pace of less than five kilometers per hour, and the physical activity accumulated sporadically as moderate was like walking at a comfortable pace of 5.8 kilometres an hour.

None of the study's participants met Canada's physical activity guidelines and only did incidental physical activity.

The research was funded by the Canadian Institute of Health Research and the Canadian Diabetes Association.