It's summer time. The weather is getting better and outdoor activities beckon. It is time to stop sitting and start working off those pounds gained over the winter. Unfortunately, sitting has reached epidemic proportions. What is contributing to the longer sitting times and what can be done to combat a sedentary lifestyle?
It seems that people are sitting more and sitting for longer periods of time. A large study compared sitting times from 2001 to 2016. During that time, the total time spent sitting in a day increased by one hour per day, in both adolescents and adults. Total sitting in time in adolescents went from 7 hours per day to 8.2 hours per day while adults went from 5.5 hours per day to 6.4 hours per day. In breaking down the cause for the increase, the researchers found that the time watching television or videos was the same, about 2 hours per day. However, the time spent sitting in front of a computer during free time, not for work or for school, rose significantly. In 2001, 43% of children and 29% of adults used a computer for more than one hour per day. By 2016 those numbers rose to 56% in children and 50% in adults.
All of that computer clicking can be deadly. There is an increased risk for death and heart disease in those who sit for prolonged periods. This risk is even higher if those who sit many hours per day don’t do the recommended weekly activity (the recommended amount of activity is 150 minutes per week for moderate exercise, 75 minutes per week for vigorous exercise). For perspective, 65% of the US population report spending less than 150 minutes per week in leisure time activity. The combination of sitting and no activity is especially deadly. How much activity is needed to offset the risk of prolonged sitting? Meeting the 150-minute/week threshold reduces the risk and the more activity, the lower the risk for death and heart disease. However, for those who typically sit 8 or more hours a day, at least 300 minutes per week of activity are needed to reduce the risk. Therefore, to lower the risk for heart disease and dying, less sitting and more physical activity is needed. In a week filled with work and home obligations, how can that be achieved? Here are some possible strategies.
There is a whole chunk of the day that is committed to commuting. The average commuting time in the US was 27 minutes one way in 2017 with larger cities having longer commute times (the average commute time in the New York City area is 38 minutes one way). For most people that time is spent sitting in a car. Changing commuting habits can help meet or exceed the recommended physical activity goals. It has been shown that walking or biking to work can lower the risk for heart disease by 11% and the risk for dying by 30%. If you must use a computer for work, or you like to spend your free time on computer, try a stand up desk. Better yet, put a treadmill under the stand up desk and do some walking while you do your clicking. This would go along way towards hitting that weekly physical activity target. If you have a dog at home, take the dog out for walks! Studies have shown that dog walkers are four times more likely to reach the weekly physical activity goal than people who do not have dogs. On average, dog owners do more physical activity than non-dog owners; about 200 minutes more per week! In addition, dog owners (and especially dog walkers) have a lower risk for heart attack and heart deaths. If you can’t walk or bike to work and don’t have a dog, try doing a simple, low-cost exercise. A study showed that young men who could complete 40 pushups had a lower risk for heart disease than those who could do 10 or less pushups.
If you don’t have a dog and don’t like to do pushups, start a walking regimen. A goal of 10,000 steps per day is thought to be associated with good health. Why 10,000 steps? How was that number derived? What is the data? Despite the fact that 10,000 steps per day is touted in the media and is the goal set on wearable devices and smartphones, no one really knows where the number came from. It is thought to have originated in Japan in the 1960’s by a company trying to promote their pedometers, but there was no hard data to support it. More recently, the Women’s Health Study (16,000 women, average age 72 years) was able to provide some clarity. In the study, women who took 4400 steps per day had a lower death rate than those who walked less (2700 steps per day or less), For every additional 1000 steps per day, the risk decreases by about 10%. This leveled off at about 7500 steps per day. This means that the minimum number of steps per day needed to lower the risk for death and heart disease is 4400 steps per day and there is no further benefit beyond 7500 steps per day. How does this fit into the goal of 150 minutes per week of activity? Calculations show that about 7000 steps per day may be sufficient to achieve the 150-minute per week goal.
So, stop sitting. Stop clicking. Start biking to work. Or walking the dog. Or doing pushups. Or start a walking program with a goal of at least 4400 steps per day and ideally 7500 steps or more per day. Remember, however, that if you sit for 8 hours a day, a higher number of steps, about 14,000 steps per day, are needed to offset the detrimental effects of prolonged sitting. Don’t let your computer do you in!
