Weak bladder and added years, seem to go hand-in-hand. I've done sit-ups 5 days a week, for years. Still, I have some problems every now and again. I lift weights. And I walk a couple miles a day. And yet I have problems. I know lots of women, who've gone or are going through menopause who have problems with the bladder. In fact, lots of women at all ages have that problem. I'd even venture to say, "It's a women thing." So, you're not alone.
Some of it could be structural: cramps, period, then menopause. But I doubt if a man has a clue what we gals suffer. It might be wise to ask a female doctor about this particular discomfort. Good luck!!!