Amid concerns that sitting is the new smoking, a new study showed that being sedentary for over 8.5 hours daily or 60 hours a week while commuting, in office, or at home can make you age faster and raise significant health risks.
Importantly, the study showed that a young age or 20 minutes of moderate activity like walking cannot buffer the effects. Instead, vigorous activity like running or cycling for 30 minutes daily can help, but not completely.
Chandra Reynolds, Professor in the Department of Psychology and Neuroscience at the University of Colorado Boulder in the US, said that "sitting less throughout the day, getting more vigorous exercise, or a combination of both may be necessary to reduce the risk of premature ageing in early adulthood".
The team analysed more than 1,000 people with an average age of 33, and included 730 twins, to explore how prolonged sitting impacts cholesterol and body mass index (BMI) in young adults.
The participants logged 9 hours of sitting daily while engaging in moderate physical activity between 80 and 160 minutes.
The results, published in the journal PLOS One, noted that “the more one sat, the older one looked”.
Further, the team said that young adults who sat 8.5 hours per day and performed at or below current exercise recommendations could be in a "moderate to high risk" category for cardiovascular and metabolic disease.
"Taking a quick walk after work may not be enough," said Reynolds, noting that the "associations are already emerging in early adulthood."
On the other hand, people who did a vigorous exercise like running or cycling for 30 minutes daily had cholesterol and BMI measures that looked like those of individuals 5 to 10 years younger. However, it was not enough.
The researchers said that one should reduce sitting time at work by using a standing desk, taking breaks, and organising walking meetings.