New research published in the Journal of the American College of Cardiology has shown that spending 10.6 or more hours per day sitting or reclining raises your risk of cardiovascular disease and death, even if you exercise regularly.
The study used data from nearly 90,000 participants in the UK Biobank. Participants wore an accelerometer for one week that measured their levels of exercise and sedentary time. Participants were then followed for a median of eight years, during which they were monitored for heart problems including atrial fibrillation, heart attacks, heart failure, and cardiovascular mortality. The goal of the study was to see how sedentary behavior is related to cardiovascular disease and how exercise affects outcomes.
The results showed that those who had the most sedentary time per day, about 10.6 hours per day on average, had a greater risk of heart failure and cardiovascular mortality. Sedentary time of 10.6 hours per day also marked an inflection point, a key threshold that was tied to a greater risk of cardiovascular issues. Those who had higher time sedentary during the day also had greater risk of being diagnosed with atrial fibrillation and having a heart attack. The higher risks of heart failure and cardiovascular death among people with more than 10.6 hours per day of sedentary time remained true even for people who were getting the recommended amount of moderate-to-vigorous physical activity (150 minutes of moderate activity or 75 minutes of vigorous activity per week).
The authors noted that too much time spent sitting or reclining every day can be detrimental to heart health, even for people who exercise regularly. Additionally, 10.6 hours per day seems to be a key threshold at which heart risk increases. In the future, public health guidelines may incorporate both exercise recommendations and maximum sedentary time recommendations to reduce heart risks.
Sources: Journal of the American College of Cardiology, Science Daily