I'm really surprised that nobody here has mentioned D-Mannose.

For a time, I used to get UTI even if I just thought about it. It was both painful and frustrating. I tried nearly everything to keep it at bay, from homeopathy to cranberry, to unfortunately when it got bad, antibiotics (which sucked because then it usually meant I got an yeast infection afterwards). I even got the procedure to widen my urethra which was more painful than it was effective. Along the way, I found out about D-mannose.

It's a type of sugar, and say what you will, it works immensely well. Cranberry works, but if you're full-blown into an infection, it doesn't work so well. D-mannose does. The only drawback is that it's not cheap. The cheapest I found was on iherb.com.

Until you can get your bladder/urethra to settle down, you can take d-mannose every day and then you can have some before a workout if you know that's a trigger.

Good luck!