Epidemiological studies as well as both longitudinal animal and human inactivity studies indicate that low physical activity is associated with the pathophysiology of type 2 diabetes mellitus (T2DM) and obesity, and recently it has been estimated that physical inactivity (worldwide) causes 7% of the burden of disease related to e.g. T2DM. Physical inactivity, a high energy dietary intake, and T2DM are also associated with dementia, depression, and impaired cognitive function. It is critical that we understand how inactivity alters body composition, glucose and lipid metabolism, and cognitive function, if normal physical activity can prevent these changes, and if there are any differences between sexes.

The present protocol is divided in several in several sub-studies:

1. To test whether and how a physically inactive lifestyle will influence body composition, glucose and lipid metabolism, and cognitive function.
2. To test whether normal physical activity can prevent the deleterious effect of a physically inactive lifestyle despite a high-caloric intake.
3. To test whether the influence of a physically inactive lifestyle combined with a high-caloric intake differs between sexes.

Inclusion Criteria:

• Normal physical active
• Healthy
• 18-40 y of age
• Non-smokers

Exclusion Criteria:

• Pregnancy
• Diabetes in family