A single bout of Interval-Walking (IW) exercise is superior to energy-expenditure and time-duration matched Continuous Walking (CW) exercise upon improving glycemic control. The reason IW is superior is unknown.

This study will look into whether it is the larger peak intensity during IW or if it is the alternating exercise pattern that is responsible for the larger improvements seen.

Subjects with type 2 diabetes will be included in a crossover, counter-balanced, controlled study, where each subject will undergo three trials. Trials will be identical except the following interventions:

1. One hour of rest (Con)
2. One hour of classical interval walking (repeated cycles of 3 min of fast and 3 min of slow walking; IW3)
3. One hour of fast alternating interval walking (repeated cycles of 1 min of fast and 1 min of slow walking; IW1).

After the interventions subjects will undergo a standardized mixed meal tolerance test, with consecutive measurements of blood glucose, insulin and c-peptide.

Inclusion Criteria:

• Type 2 diabetes mellitus
• Body mass index > 18 but < 40 m2/kg
• Agreement to pause antidiabetic medication from 2 days before to after each trial

Exclusion Criteria:

• Pregnancy
• Smoking
• Use of exogenous insulin
• Contraindication to increased levels of physical activity
• Evidence of thyroid, liver, lung, heart or kidney disease