Recruitment and Randomization CRC patients will be recruited from the oncology clinic, Rigshospitalet and the gastro-intestinal surgical ward at Hvidovre Hospital. Patients, who have undergone adjuvant chemotherapy, will be informed of the study during their final visit at the oncology clinic. Patients in active surveillance will be informed of the study at the first clinical visit, at least one month after surgery. The responsible clinicians and nurses in the clinical department will present patients with the written information of the study and gather contact information for interested participants to the study coordinator for more information of the study. Before any study related test-procedures are initiated, patients will sign informed consent, and undergo medical screening including former and present medication, physical examination including resting EKG by a study physician to determine if the patient can be included in the trial and subsequently scheduled for baseline assessment.