New research published in the British Journal of Sports Medicine suggests that as little as 20-25 minutes of physical activity per day may counter the increased risk of death associated with a sedentary lifestyle. The study indicates that higher levels of daily physical activity are linked to a reduced risk of death, regardless of the amount of time spent sitting each day.
In developed nations, adults spend an average of 9 to 10 hours per day sitting, particularly during working hours. Prolonged sedentary behaviour is associated with an elevated risk of mortality. The study aimed to overcome limitations in previous research, which relied on aggregated data. Researchers pooled individual participant data from four groups of individuals equipped with activity trackers to explore the interplay between physical activity, sedentary time, and mortality risk.
The study included data collected from 2003 to 2019 from various sources, involving nearly 12,000 people aged 50 or older who were monitored for a minimum of 2 years. The analysis revealed that individuals who were sedentary for over 12 hours a day had a 38% higher risk of death compared to those with 8 hours of daily sedentary time. However, this risk was offset by engaging in more than 22 minutes of moderate to vigorous physical activity daily.
While higher levels of physical activity were associated with a reduced risk of death, the relationship between sedentary time and mortality was influenced by the amount of physical activity. An additional 10 minutes of physical activity per day was linked to a 15% lower risk of death for individuals with fewer than 10.5 daily sedentary hours and a 35% lower risk for those with over 10.5 daily sedentary hours.
The study, being observational, cannot establish causation. Additionally, the researchers couldn't measure changes in physical activity and sedentary behaviour over time. Factors like diet, mobility issues, and general health weren't fully considered, and activity trackers may not accurately classify all types of physical activity.
The researchers suggest that small amounts of moderate to vigorous physical activity can be an effective strategy to mitigate the risk of mortality associated with prolonged sedentary time. Encouraging physical activity can provide substantial health benefits for individuals.