How many hours do you spend sitting in a chair every day? Eight hours in the office plus three hours in front of the TV after work is the norm for many people.     You probably don't need an expert to tell you that sitting too much is not good for your health--from an increased risk of heart disease and obesity in the long term,to reduced cholesterol maintenance in the short term,not to mention the strain on your neck and spine.     To make matters worse,many researches show a good diet and regular exercise call't reduce the negative effects of sitting too much.     A 2010 study of nearly 9,000 Australians found that for each additional hour of television a person watched per day,the risk of dying rose by 11 percent.Another study tracked the health of 123,000 Americans between 1992 and 2006.The death rate for men who spent six hours or more per day sitting was about 20 percent higher than for men who sat for three hours or less.     So what can we do about it? Health experts suggest we break up those many hours spent sitting with more hours spent standing.     The BBC conducted a simple experiment with a group of 10 volunteers who usually spent most of the day sitting.They were asked to stand for at least three hours a day.The researchers took measurements Oil days when the volunteers stood,and when they sat around.When they looked at the data there were some striking differences,the BBC reported. Blood sugar leveled off much quicker on the days when the study subjects stood compared with the days they spent in a chair.Standing also burned more calories----about 50 calories an hour.A member said although doing exercise offers many proven benefits,our bodies also need the increase in muscle activity that standing provides. The researchers believe that even small adjustments,like standing while talking on the   phone,will help. What is the purpose of the experiment in the text?
To help the 10 volunteers to lose weight. To find the difference between standing and sitting. To prove the benefit of standing. To teach us how to control blood sugar.