"20 Minutes of Daily Physical Activity: A Lifesaver for Those Sitting Too Much"

A recent study conducted by Norwegian researchers indicates that engaging in 20 to 25 minutes of daily physical activity can potentially counterbalance the increased mortality risk associated with prolonged sitting among adults, particularly during the work day.

The study revealed that engaging in more than 22 minutes of moderate to vigorous physical activity per day was linked to a decreased likelihood of mortality. The analysis encompassed nearly 12,000 individuals aged 50 or above who were monitored using activity trackers for a minimum of two years.

Out of the participants, 5,943 individuals spent less than 10.5 hours sitting each day, while 6,042 individuals sat for 10.5 hours or more daily. Over a span of approximately 5 years, 7% of the participants (805 individuals) passed away, as indicated by death registries. Among these, 357 individuals spent less than 10.5 hours sitting daily, whereas 448 individuals sat for 10.5 hours or more each day.

Upon examining the activity tracker data for participants who engaged in less than 22 minutes of daily physical activity, it was observed that sitting for over 12 hours per day was associated with a 38% higher risk of mortality compared to sitting for 8 hours.

Furthermore, for individuals who spent more than 10.5 hours sitting each day, an additional 10 minutes of moderate to vigorous physical activity was linked to a 35% lower risk of death.

Researchers analyzed individual participant data from four groups of individuals to investigate the potential impact of physical activity on the correlation between prolonged sitting and increased mortality risks. The study aimed to determine the level of physical activity required to mitigate these risks. Participants provided information on various factors that could potentially influence the study outcomes, including their gender, body weight, smoking habits, alcohol consumption, and history of cardiovascular disease, cancer, or diabetes. However, the researchers acknowledged certain limitations of the study, such as the inability to track changes in physical activity and sitting time over time. Additionally, the analysis did not consider other influential factors like participants' dietary habits and overall health. Furthermore, the researchers noted that activity trackers were not always capable of accurately identifying the specific types of activities performed by the participants. In conclusion, the researchers found that even small amounts of moderate to vigorous physical activity on a daily basis could help mitigate the heightened mortality risks associated with prolonged sitting.

In developed nations, it is observed that adults typically spend an average of 9 to 10 hours per day engaged in sedentary behavior, primarily during working hours. Researchers have found that this highly sedentary lifestyle is linked to an increased risk of mortality.

Previous studies examining the benefits of physical activity in mitigating the negative effects of prolonged sitting have often relied on aggregated data, resulting in a generalized approach. To address this limitation, the researchers conducted a comprehensive analysis by pooling individual participant data from four distinct groups. These participants were equipped with activity trackers to assess the potential impact of physical activity on the association between sedentary time and mortality, as well as the reciprocal influence of these factors. Additionally, the researchers aimed to determine the optimal levels of physical activity and sitting time that could influence the risk of mortality.

By utilizing this approach, the researchers sought to provide a more nuanced understanding of the relationship between sedentary behavior, physical activity, and mortality risk.

This is an observational study, which means that it cannot establish a cause and effect relationship. The researchers also acknowledge that they were unable to repeat measurements of physical activity and sedentary hours, which prevents any assessment of changes over time.

Additionally, important factors such as diet, mobility issues, and general health were not taken into account. It should also be noted that activity trackers may not accurately classify all types of activity and their corresponding intensity, such as cycling, resistance exercises, and gardening.

Despite these limitations, the researchers conclude that engaging in small amounts of moderate to vigorous physical activity (MVPA) may be an effective strategy to reduce the risk of mortality associated with high sedentary time. They suggest that accumulating more than 22 minutes of MVPA can eliminate this risk.