Sitting for long periods of time can be quite harmful to the body. The average person sits for about 9.3 hours per day — more than the average person spends sleeping. The act of sitting can cause many immediate changes to the body. As soon as a person sits down, electrical energy in the legs stops, calorie burning drops to one calorie per minute, and enzymes that break down fat drop to 90 percent. Two hours after sitting, the amount of good cholesterol in the blood drops by 20 percent. After 24 hours, the effectiveness of insulin drops by 24 percent, increasing the risk of diabetes.
Many studies have shown that prolonged sitting can cause organ damage, muscle degeneration, poor circulation, obesity and back pain. In fact, one meta-analysis published in the Annals of Internal Medicine showed that prolonged sitting was associated with higher mortality from all causes of death including cancer, cardiovascular disease and type 2 diabetes.
Although it seems as though regular exercise could reverse some of the damage associated with regular sitting, a study published by the American College of Sports Medicine suggests that sedentary lifestyle is a health risk factor, regardless of whether regular exercise is being done.
What can be done if a person is often required to sit all day? Two studies show that just walking or stretching for a couple of minutes every hour is enough to mitigate the harms of sitting.
The first study analyzed data from 3,626 United States adults who participated in the National Health and Nutrition Examination Survey conducted by the Center for Disease Control and Prevention. These adults agreed to wear health monitors, which tracked their movement throughout the experiment. After three years, the researchers counted the patients that had died to calculate the risk of dying prematurely and whether time spent sitting had an effect on the outcome.The researchers found that standing was no better than sitting when it came to premature death. However, it was found that two minutes of walking every hour decreased the chance of dying prematurely by 33 percent.
While the data from this study is quite novel, the study itself was observational. As a result,we cannot conclude that walking actually reduces the chance of premature death as there may be other factors at play. For example, it is possible that those that are healthier to begin with walk around more than less healthy individuals.
An additional study published last year in the British Journal of Sports Medicine suggests that those who sit for most of the day should aim to stand or walk for about 2 hours per day, and progress to walking about 4 hours per day. In addition, people should break up time spent sitting with a few minutes of standing or walking.
For every hour that you spent in the library studying, spend a few minutes getting up from your chair and walking around. Any amount of walking is helpful, whether it be just around your table or through the book racks. If it is too cold to go outside, there are indoor wellness trails set up in different buildings around campus. Even just a little bit of stretching at your desk can help undo the harms of prolonged sitting.