Washington DC [US]: According to research published online in the British Journal of Sports Medicine, just 20-25 minutes of physical activity each day may be enough to offset the increased risk of death from a sedentary lifestyle.
But higher daily tallies of physical activity are linked to a lower risk, irrespective of the amount of time spent seated every day, the findings show.
In developed nations, adults spend an average of 9 to 10 hours every day sitting down--mostly during working hours.
During this study, the researchers pooled individual participant data from four groups of people fitted with activity trackers to find out whether physical activity might modify the association between sedentary time and death, and vice versa, and what amount of physical activity and sitting time might influence risk.
About 12,000 people aged at least 50 were included in the analysis. They had a minimum of 4 days of 10 daily hours of activity tracker records, had been monitored for at least 2 years, and had provided details of potentially influential factors: their sex, educational level, weight, height, smoking history, alcohol intake, and whether they had current and/or previous cardiovascular disease, cancer and/or diabetes.
In all, 5943 people spent fewer than 10.5 hours sitting down every day; 6042 clocked up 10.5 or more sedentary hours.
Linkage with death registries showed that during an average period of 5 years, 805 (7%) people died, 357 (6%) of whom spent under 10.5 hours sitting down every day, and 448 of whom clocked up 10.5 hours or more.
The analysis of the activity tracker data showed that being sedentary for more than 12 hours a day was associated with a 38% heightened risk of death compared with a daily tally of 8 hours--but only among those totting up fewer than 22 daily minutes of moderate to vigorous physical activity.
More than 22 daily minutes of moderate to vigorous physical activity was associated with a lower risk of death.
"Efforts to promote physical activity may have substantial health benefits for individuals," the study found. (with ANI inputs)
