I found this on Mount Sinai website :

"To hasten the recovery of urinary control, we teach you pelvic floor exercises to strengthen the urinary sphincter. These exercises are known as Kegel exercises. Basically, they consist of tightening the urine control muscle (the sphincter muscles) 10 to 20 times every hour to strengthen the muscle that controls urine flow. We may recommend other behavioral strategies as well, including timed voiding, double voiding, and reduced fluid intake, which can significantly help facilitate urinary control and can be started shortly after surgery."

As you can see, they mention "reduced fluid intake" also. It made me thinking - is your PT working with RP patients or is just helping people with regular incontinence ?