Before surgery, urinary control comes from several structures working together. Prostate removal changes that arrangement, so the remaining muscles — including the pelvic floor — carry more of the job.
Add post-surgical swelling, tissue healing, deconditioning, and changes in pressure control, and leakage with standing, coughing, lifting, or walking is common early on.
The pelvic floor helps close the urethra, supports the bladder, and responds to changes in abdominal pressure. Good control depends on strength, but also on timing, endurance, and the ability to relax between efforts.