 Nature and extent of the burden and risks associated with participation, benefit and group relatedness: Despite participation in this study being reserved for those without any contra-indication for physical exercise and despite the conclusion of the American College of Sports Medicine Roundtable on Exercise Guidelines for Cancer Survivors that exercise is safe during and after cancer treatment 13, in doing physical exercise there is always a risk of sports straininjury. However, regarding the nature of the targeted intensity of exercise moderate, this risk will be low and the investigators expect the benefits both physically and psychologically to far outweigh possible risks. 