- Level of daily physical activity To evaluate the level of moderate-to-vigorous-intensity physical activity all participants will be equipped with an accelerometer (Axivity AX3, Newcastle, UK) for 10 consecutive days, 3 times during the intervention period - at baseline and after 4-18 weeks and 52 weeks after enrolment. One accelerometer will be placed with patch (Leukomed T, BSN medical, Germany) on the lateral side of the right thigh and one accelerometer on the lumbar spine. The patients will be instructed not to remove the accelerometer during the three periods. The accelerometers can be worn when taking a shower, swimming etc.