Stress Incontinence Running after Prostatectomy

It's 30 months since my surgery and I am very satisfied overall with the results. I only occasionally use a light shield and most of the time it's only "just in case" I have a slight driblle (typically after urinating). I can engage in exercising without any issue, except for running. That's a bit of a problem for me, since I have been a runner for most of my adult life. When I run, I need to use a light to medium pad. That's not really a problem, but I'm curious as to why I can do push-ups, sit-ups, swim, etc. without any stress incontinence, but when I run I must wear a pad.

I have been do kegel exercises regularly since before my surgery, and, as I've explained, I generally don't have an issue. Even with all of the coughing through a bout of bronchitis, I didn't have any leaking. Is there something specific about running? Are there specific pelvic muscles I could strenghen with exercises other than kegels?