Ekelund noted how physical activity affects the immune system, reduces the risk of inflammation, and may reduce blood pressure, among other health benefits. All of those changes are then associated with a reduction in risk of major chronic diseases such as cardiovascular disease and cancer, which are “the major killers in Western societies,” he said.
Just five more minutes can make a difference
Ekelund and his team wanted to use devices to actually measure physical activity – versus self-reported data – so they could rule out the confounding factors (such as people who overestimate how much they actually move) that tend to influence these types of studies.
“We wanted to expand on the current knowledge,” Ekelund said. “If all in the population made a small change, how many deaths could that potentially prevent during this follow-up period where we studied these individuals?”
Participants in the study were asked to wear activity trackers, with follow-ups averaging eight years. The researchers took other variables into account, such as history of diseases, age and body mass.
The benefits increased with longer times spent exercising. For example, being active at moderate intensity for an additional 10 minutes per day was associated with a 15% reduction in all deaths among most adults during the follow-up period, the study found.
Reducing sedentary time was also helpful. Data showed that decreasing inactivity by one hour among the majority of adults was associated with a 13% reduction in all deaths, and a 6% reduction among the least active adults in the follow-up period.
Try small changes
Amy W. Pollak, a general cardiologist who specialises in preventive cardiology at Mayo Clinic Florida, and who wasn’t involved in the new research, said the finding is “exciting because it’s very tangible”.
Sometimes making “optimal life choices” can feel “overwhelming when we’re trying to balance work and life stressors, health issues, financial concerns and competing interests,” Pollak said. “This type of study says there is good data to suggest based on this modelling, that just small, five-to-10 minute increases in moderate to vigorous activity can make a big impact on a hard endpoint, like mortality for populations.”
The authors of the study cautioned that these findings are meant to highlight potential benefits for the population as a whole and shouldn’t be used as personalised exercise advice. They also acknowledged the need for more research in low- and middle-income countries.
Speaking broadly, Ekelund emphasised that making realistic changes in your daily activity, especially if you aren’t active to begin with, can lead to good health.
“It’s always difficult to change behaviours, and physical activity behaviour is no exception,” Ekelund said. “It’s hard, but if you build it up gradually, starting slow, it could be worthwhile. And for those who are already active, just continue being active.”