Are sedentary lifestyles the new scourge of the century?
After peaking during the Covid-19 pandemic, physical inactivity levels do not appear to have improved much since.
A new American study reveals that people are walking much less than before the pandemic, especially younger adults, which could ultimately increase the risk of cardiovascular disease, obesity and diabetes, and have an impact on mental health.
The World Health Organization (WHO) recommends that adults should do at least 150 to 300 minutes of moderate-intensity aerobic physical activity a week.
But these recommendations are not necessarily being met.
In October 2022, the WHO even estimated that a quarter of adults did not engage in physical activity at the recommended levels worldwide, as well as more than 80% of adolescents worldwide.
This observation is now reinforced by an American study that shows that the country's residents walk significantly less than they did before the Covid-19 pandemic.
Nearly 600 fewer steps per day
Based on data from the National Institutes of Health (NIH) All of Us Research Program, the study specifically looked at steps taken by 5,443 activity sensor wearers, a majority of whom were white women, with a median age of 53.
The analysis covers four years, divided into two distinct pre- and post-pandemic periods, from January 1, 2018, to January 31, 2020, for the former, and from June 1, 2020, to December 31, 2021, for the latter.
Published in the journal JAMA Network Open, the study found that participants took an average of 575 fewer steps per day in the wake of the pandemic.
Researchers at Vanderbilt University Medical Center in Nashville say they found "no association between reduced step counts and sex or comorbidities such obesity, diabetes, coronary artery disease, hypertension or cancer."
On the other hand, they noted disparities according to socio-economic status – the most disadvantaged taking fewer steps – as well as levels of psychological stress and depression, and even vaccination status. All these factors may affect levels of physical inactivity.
"These findings suggest a consistent, widespread, and significant decline in activity following the onset of Covid-19 in the US. Vulnerable populations, including individuals at a lower socio-economic status and those reporting worse mental health in the early Covid-19 period, were at the highest risk of reduced activity," the study authors write.
Younger adults most impacted
But the most compelling criterion remains age.
And, perhaps unexpectedly, it was not Generation X and Baby Boomers who walked the least, but the participants aged 18 to 30.
The study specifies that each 10-year decrease in age was associated with a 243 reduction in steps per day, on average.
Interviewed by CNN, study author Dr Evan Brittain, said: "If this persists over time, it could certainly raise the risk of cardiovascular disease, obesity, hypertension, diabetes and other conditions strongly linked to being sedentary. However, it’s too soon to know whether this trend will last."
If the time spent using screen-based devices is systematically cited as the reason for this increase in sedentary behavior, there are actually various reasons involved.
The widespread uptake of working from home is not unrelated to this decrease in physical activity.
This is why the study authors told CNN that they would encourage remote workers to invest in a standing desk, a desk with a treadmill, or a desk with an integrated bicycle.
They also recommend that employers encourage periodic breaks for exercise, which would be beneficial not only for physical health, but also for mental health, as recent studies have shown. – AFP Relaxnews