Having a job that requires prolonged sitting is likely to be associated with increased heart attack and premature death risks unless you also exercise. A study involving 481,688 people followed for an average 12 years found that those who had jobs that required prolonged sitting had a 16 percent higher risk for death and a 34 percent increased risk for death from heart attacks, compared to those who had jobs that required them to move actively about. To reduce their risk for premature death to those who do not have jobs that require prolonged sitting, they needed to move actively for at least 15 to 30 minutes per day (JAMA Network Open, 2024;7(1):e2350680).
Another study of nearly 12,000 people ages 50 years or older found that those who sat 12 or more hours a day had a 38 percent higher risk of death than those who sat eight hours a day. Just 10 minutes of moderate exercise reduced the risk of death by 35 percent, and exercising for 22 minutes or more completely eliminated their increased risk (British Journal of Sports, October 2023).
Prolonged Sitting Has Not Been Shown to Shorten Lives of Vigorous Exercisers
Extensive data show that for the average person, increased sitting time is associated with an earlier death. However, extra sitting time does not increase risks for exercisers who get Z-line muscle fiber damage that takes extra time to heal. Vigorous exercisers and competitive athletes recover faster for their next workout if they lie or sit down after their intense workouts. To make muscles stronger, they need to exercise intensely enough to damage the muscles. You can tell that you are damaging muscles when you exercise vigorously enough to feel soreness in those muscles 8 to 24 hours later, which is called Delayed Onset Muscle Soreness or DOMS (Strength & Conditioning Journal, October 2013;35(5):16–21).
Another study followed 5836 adults, average age 56, and found that people in a group that exercised more and sat less were 47 percent less likely to die in 14 years than those in the group that exercised less and sat more (Amer J of Prev Med, July 23, 2024:S0749-3797(24)00254-X).
A review of 16 major studies found that just thirty minutes a week of strength training is associated with up to a 20 percent reduced risk for dying from any cause, or from cancer, heart disease or diabetes. Adding aerobic exercise reduced risk for dying by 40 percent (British J of Sports Medicine, June 16, 2022;56(13):755-763).
Lack of Exercise is Worse Than Prolonged Sitting
Sitting Will Not Harm Vigorous Exercisers
My Recommendations
If you have a job that requires that you sit for long periods of time, you should have some program in which you get up and move about and also have a moderate exercise program. Otherwise, you may be at increased risk for a heart attack and premature death. If you do not want to have a regular exercise program, you can help to protect yourself just by getting up every half hour or so and moving about.
