Study: NCT03106688

Intervention type: DIAGNOSTIC_TEST
Group type: ACTIVE_COMPARATOR
Intervention: fMRI imaging
Description: Using blood oxygenation level dependent (BOLD) echo-planar imaging, fMRI will be used for characterising individual differences in the brain circuits.

Intervention type: DIAGNOSTIC_TEST
Group type: ACTIVE_COMPARATOR
Intervention: fMRI imaging
Description: Using blood oxygenation level dependent (BOLD) echo-planar imaging, fMRI will be used for characterising individual differences in the brain circuits.

Intervention type: DIAGNOSTIC_TEST
Group type: ACTIVE_COMPARATOR
Intervention: [11C]carfentanil PET scan
Description: \[11C\]carfentanil is used to measure μ-opioid receptor (MOR) availability in brain.

Intervention type: DIAGNOSTIC_TEST
Group type: ACTIVE_COMPARATOR
Intervention: [11C]carfentanil PET scan
Description: \[11C\]carfentanil is used to measure μ-opioid receptor (MOR) availability in brain.

Intervention type: DIAGNOSTIC_TEST
Group type: ACTIVE_COMPARATOR
Intervention: [18F]FMPEP-d2 PET scan
Description: \[18F\]FMPEP-d2 is used to measure cannabinoid receptor type 1 (CB1) availability in brain and body.

Intervention type: DIAGNOSTIC_TEST
Group type: ACTIVE_COMPARATOR
Intervention: [18F]FMPEP-d2 PET scan
Description: \[18F\]FMPEP-d2 is used to measure cannabinoid receptor type 1 (CB1) availability in brain and body.

Intervention type: DIAGNOSTIC_TEST
Group type: ACTIVE_COMPARATOR
Intervention: [18F]-FDG PET scan
Description: Brain and body insuin stimulated glucose uptake is measured with radioligand \[18F\]-FDG.

Intervention type: DIAGNOSTIC_TEST
Group type: ACTIVE_COMPARATOR
Intervention: [18F]-FDG PET scan
Description: Brain and body insuin stimulated glucose uptake is measured with radioligand \[18F\]-FDG.

Intervention type: DIAGNOSTIC_TEST
Group type: ACTIVE_COMPARATOR
Intervention: Physical activity measures and fitness tests
Description: Physical activity will be measured over one week following the screening check-up, before the PET measurement days. For the measurement, subjects will wear Polar M600 GPS Sports Watch for the measurement period. The fitness tests will be performed at the Paavo Nurmi Centre.

Intervention type: DIAGNOSTIC_TEST
Group type: ACTIVE_COMPARATOR
Intervention: Physical activity measures and fitness tests
Description: Physical activity will be measured over one week following the screening check-up, before the PET measurement days. For the measurement, subjects will wear Polar M600 GPS Sports Watch for the measurement period. The fitness tests will be performed at the Paavo Nurmi Centre.

Intervention type: DIAGNOSTIC_TEST
Group type: ACTIVE_COMPARATOR
Intervention: Laboratory measurements
Description: Weight, height, blood pressure, medical history, and current medication are determined. Body fat percentage will be assessed using BodPod plethysmograph.

Intervention type: DIAGNOSTIC_TEST
Group type: ACTIVE_COMPARATOR
Intervention: Laboratory measurements
Description: Weight, height, blood pressure, medical history, and current medication are determined. Body fat percentage will be assessed using BodPod plethysmograph.

Intervention type: DIAGNOSTIC_TEST
Group type: ACTIVE_COMPARATOR
Intervention: Questionnaires
Description: All the participants will complete a self-administered questionnaire at baseline, and at 12 months, for assessment of leisure-time physical activity (LTPA). The following questionnaires will be completed: Behavioural inhibition / activation, Dutch Eating Behaviour Questionnaire, Yale Food Addiction Scale, PCL-Revised, Food craving State / Trait (FCS-FCST) questionnaires, Autism Spectrum Quotient, State-Trait Anxiety Questionnaire and Pain Sensitivity Questionnaire.

Intervention type: DIAGNOSTIC_TEST
Group type: ACTIVE_COMPARATOR
Intervention: Questionnaires
Description: All the participants will complete a self-administered questionnaire at baseline, and at 12 months, for assessment of leisure-time physical activity (LTPA). The following questionnaires will be completed: Behavioural inhibition / activation, Dutch Eating Behaviour Questionnaire, Yale Food Addiction Scale, PCL-Revised, Food craving State / Trait (FCS-FCST) questionnaires, Autism Spectrum Quotient, State-Trait Anxiety Questionnaire and Pain Sensitivity Questionnaire.

Intervention type: DIAGNOSTIC_TEST
Group type: ACTIVE_COMPARATOR
Intervention: Hyperinsulinemic euglycemic clamp
Description: Low-dose hyperinsulinemic euglycemic clamp technique will be used to promote glucose uptake and measure insulin sensitivity of the subjects. In the clamp study subjects are administered intravenous insulin at a steady rate of 0.25 mU/kg/min and normoglycemia is maintained using a variable rate infusion of 20 % glucose based on plasma glucose measurements, which are performed every 5-10 min from arterialized venous blood.

Intervention type: DIAGNOSTIC_TEST
Group type: ACTIVE_COMPARATOR
Intervention: Hyperinsulinemic euglycemic clamp
Description: Low-dose hyperinsulinemic euglycemic clamp technique will be used to promote glucose uptake and measure insulin sensitivity of the subjects. In the clamp study subjects are administered intravenous insulin at a steady rate of 0.25 mU/kg/min and normoglycemia is maintained using a variable rate infusion of 20 % glucose based on plasma glucose measurements, which are performed every 5-10 min from arterialized venous blood.