Inclusion Criteria:  men aged 18 or older candidates for a prostate curative treatment with RT (which includes exclusive RT +/-hormone therapy, surgery followed by RT +/- hormone therapy) AND good performance status (ECOG < 2) AND written informed consent obtained AND willing to be randomized to either group, AND willing to wear the wrist-based activity monitor during the 6-month study period.  Exclusion Criteria:  BMI <18.5 AND extra pelvic lymph node involvement or metastasis and severe medical condition(s) that would prevent optimal participation in the physical activities prescribed AND Malnutrition Universal Screening Tool (MUST) ≥ 2. It considers body mass index, weight change and acute disease effect equally and determines a malnutrition risk score. A score ≥2 identify a patient at high risk of malnutrition AND investigator does not approve participation in the study in case of severe clinical condition that would prevent optimal participation in the physical activities prescribed; any other severe medical condition or advanced age impeding the patient to adhere at the planned study follow-up period.