NEAT and Insulin Sensitivity

The effect of Non-Exercise Activity Thermogenesis (NEAT) or inactivity on insulin sensitivity and lipid metabolism is unclear. Research recently published shows that activities associated with everyday activities, summarized as NEAT, such as walking and standing, have a much greater role in energy expenditure than exercise. Therefore, the objective of the present study is to evaluate the effect of 4 days of inactivity (mainly sitting), 4 days of everyday activities (sitting, walking and standing), and 4 days of inactivity and exercise (sitting and biking) on glucose metabolism and insulin sensitivity using an oral glucose tolerance test, and on lipid metabolism in sedentary, overweight people. The investigators hypothesize that: 1. 4 days of everyday activities (NEAT) will cause an increased glucose tolerance and increased insulin sensitivity compared to 4 days of inactivity in sedentary, overweight people. 2. 4 days of exercise will improve glucose tolerance and insulin sensitivity more than 4 days of NEAT with equal energy expenditure, in sedentary, overweight people. 3. Fasting triglyceride will have the same course as glucose, mentioned in 1. and 2.