The purpose of this study is to evaluate the potential interaction between metformin and exercise in order to optimize clinical guidelines for treatment of T2D.

Physical activity is a first line treatment for patients with type 2 diabetes (T2D ), however, the vast majority of patients with T2D do not achieve satisfying glycemic control with physical activity alone, which is why pharmacological treatment with metformin is most often initiated. It is known that metformin and exercise both activates AMPK, which results in many different metabolic effects. Because of this similarity, an interaction between metformin and exercise is plausible, but knowledge in the area is sparse. With this study the investigators aim to look at the individual and combined effects of metformin and exercise in order to investigate whether an interaction occur. An Interaction will have tremendous clinical importance for patients with T2D given current guidelines where the vast majority of these patients are recommended both exercise and metformin treatment.

The investigators hypothesize that metformin treatment reduces self-selected exercise intensity, which may be explained via decreased mitochondrial complex 1 function, increased blood lactate levels, heart rate and RPE during exercise. Furthermore exercise-induced AMPK-activation is reduced with metformin treatment.

Inclusion Criteria:

• male
• HbA1c < 39 mmol/l
• BMI < 25
• structured physical activity < = 150 min/week
• apparently healthy

Exclusion Criteria:

• smoking
• daily pharmaceutical treatment
• contraindication to increased levels of physical activity
• ALAT/ASAT elevated 3 times above upper normal values
• renal insufficiency (eGFR < 60 ml/min)
• prior history of lactic acidosis