Preoperative Physical Activity Improvement with the Use of Activity Trackers in Patients Undergoing Radical Cystectomy—A Bicentric, Open-label, Randomised Controlled Trial: A Clinical Study Protocol of the PreAct Trial - Johannes Hermann Kilz; Marie Angela Sidoti Abate; Victoria Luise Simone Wieland; Luisa Egen; Caelan Max Haney; Aleksander Antoniewicz; Alexander Studier-Fischer; Thomas Stefan Worst; Maurice Stephan Michel; Patrick Honeck; Niklas Westhoff; Maximilian Christian Kriegmair; et al. (European Urology Open Science)