- End of week 1: phone call. An investigator will call the patients one day before the end of the recording period of physical activity to remind them to send back the accelerometer. Furthermore, patients will reply by telephone to the generic HRQoL questionnaire (EQ-5D-5L questionnaire, please see details of this questionnaire in the "Cost-effectiveness of the intervention" section). This questionnaire will be administered repetitively throughout and at the end of the intervention.