Don't Sit This One Out
By Cynthia K. Buffington, PhD
Our modern lifestyle has dramatically increased the time we spend sitting. Over the course of a typical day we may sit for breakfast; sit while traveling to work, sit at work like half of the Americans do, sit for lunch, sit in transit home, sit while eating dinner, sit in front of the television or computer and finally sit down to then lie down and go to sleep.
Most Americans spend more than 9 hours per day in sedentary activity, mainly sitting, and too much sitting can be as bad for your health as performing no activity at all.
Large population studies find a close relationship between the time spent sitting and heart disease, diabetes, and all-causes of mortality. Such associations may exist, in part, because people who sit for long periods are heavier than those that have a less sedentary lifestyle. Data from a number of studies show that the greater the time a person spends sitting, the more obese they are likely to be. Furthermore, prolonged sitting tends to favor the distribution of fat into abdominal regions. Abdominal fat (belly fat) is closely linked to the development of heart disease, diabetes, hypertension, lipid abnormalities, fatty liver disease and other metabolic conditions.
Sitting contributes to obesity and associated diseases for several reasons. First, the amount of calories the body burns is low while sitting, increasing the risk for weight gain. Secondly, too much time spent sitting causes metabolic defects that increase body fat and the risk for disease. Prolonged sitting, for instance, reduces the entry of fat into muscle and, in doing so, decreases the amount of fat burned (oxidized) for energy. This makes more fat available for storage in adipose (fat) tissue. To make matters worse, sitting for too many hours each day may cause insulin resistance, a condition that increases insulin levels and the accumulation of fat into fat storage depots. Insulin resistance also contributes to the development of diabetes and to other metabolic health concerns including heart disease, hypertension, fatty liver disease, and more.
Recent studies find that frequent interruptions to sitting prevent or improve metabolic defects contributing to obesity and disease, including insulin resistance and muscle changes. Such interruptions may involve: 1) standing to talk on the phone or performing other tasks that do not require sitting, 2) walking to the water fountain or up and down the hall at least every hour, 3) performing sitting exercises and stretches while seated, 4) stepping or pedaling on specially designed devices to be used while sitting, 5) using a walking desk or other office equipment designed to enhance movement, and 6) sitting on an exercise ball instead of a chair at work or home. Performance of mild activity for short periods to interrupt sitting has a positive impact on body size and health.
How much time do you spend sitting each day? This week, keep a diary of the amount of time you spend sitting. This includes sitting time at work and how long you may sit at any one time anywhere. Also record the amount of time you spend in transit to work or to the store, how long you sit while eating meals, time spent sitting in front of the television or at a movie. Keep this record for one week and see how much time you spend sitting. The following week, continue to keep a record of sitting time but also record any interruptions to sitting you are able to achieve. To do this, you may initially need to set a timer on your phone or computer to remind you hourly to stand, walk or perform some mild activity to interrupt sitting. Keep in mind that sitting is a serious threat to your health and longevity so get up frequently and out of that chair. Don’t sit this one out!