For people with high blood pressure, getting plenty of exercise is extremely important. However, some people feel that if they live in an area with high air pollution, they should not exercise outdoors as it may do more harm than good.
According to new research published in the American Heart Association’s journal Circulation, people who regularly exercise have a lower risk of high blood pressure—even those who live in areas where air pollution is high.
With over 91% of the world’s population living in areas where air quality does not meet the World Health Organization’s (WHO) guidelines, it is essential to assess the risk-benefit relationship between air pollution and physical activity.
“Extended outdoor activity in urban areas increases the intake of air pollutants, which can worsen the harmful health effects of air pollution,” said study author Xiang Qian Lao. “While we found that high physical activity combined with lower air pollution exposure was linked to a lower risk of high blood pressure, physical activity continued to have a protective effect even when people were exposed to high pollution levels. The message is that physical activity, even in polluted air, is an important high blood pressure prevention strategy.”
For the study, researchers studied more than 140,000 non-hypertensive adults in Taiwan for an average of five years. They were divided into groups based on their weekly physical activity levels—inactive, moderately active, or highly active. They were also classified into groups according to their level of exposure to air pollution.
It was found that overall, people who are highly active and exposed to low levels of pollution had a lower risk of developing high blood pressure. Participants who were inactive and exposed to highly polluted air had a higher risk of high blood pressure.
Each increase in fine particle matter of air pollution was associated with a 38% increase in the risk of incident hypertension. Still, each increase in physical activity level led to a 6% lower risk of hypertension. Researchers believe these findings suggest that reducing air pollution is more effective in preventing high blood pressure.
The benefits of regular physical activity help regardless of the pollution level. Participants who exercised moderately had a 4% lower risk of high blood pressure than those who didn’t exercise. Those who exercised at a high level had a 13% lower risk of high blood pressure than those who did not exercise at all.
Air Pollution Risk
The American Heart Association issued a scientific statement in 2004, concluding that exposure to air pollution contributes to cardiovascular illness and death. In 2010, it was updated to include risk of heart attack, stroke, arrhythmia, and heart failure.
As the most extensive study to analyze the combined effects of air pollution and regular physical activity on high blood pressure, the findings were relatively clear and could add to the scientific statement. Regular physical activity is a safe approach for people living in moderately polluted regions to prevent high blood pressure. This study also puts a spotlight on the effect air pollution can have on high blood pressure.