A study published in BMC Medicine reveals that long-term exposure to polluted air can contribute to reducing the benefits of physical activity. A good excuse to hang up your sneakers and become one with the sofa?
No, because the authors talk about decreasenot of elimination: physical activity would still reduce the risk of mortality from any cause, but the beneficial effect would be smaller.
important differences. The research team analyzed data on over one and a half million people monitored for more than a decade and from several countries including the United Kingdom, China and the USA. The results show that those who performed at least two and a half hours per week of moderate to vigorous physical exercise (such as running) had a 30% lower risk of dying during the study period than those who did not exercise as much.
For equally trained people, who however lived in areas where the average annual level of PM2.5 was equal to or higher than 25 μg/m³ (almost half of the world population), the risk reduction stopped at 12-15%.
Fine dust, them again. If the PM2.5 level exceeded 35 μg/m³ the benefits of physical exercise were further reduced, and the risk of death from cancer was practically the same as that of people who did not carry out moderate to vigorous activity.
The limitations of the study. As with many studies, this one has some limitations – in particular the fact that the participants involved were mainly from high-income countries, and that there was a lack of data on their diet and indoor air quality.
However, the authors took into account many other factors, such as educational level, income, health-related habits such as smoking and the presence or absence of chronic diseases.
