Breaking news: Olympic swimmers pee in the pool. A lot. From a former USA national team member:
Before a race is an interesting time. It depends on the meet and to some extent the color of the pool deck. I kid you not. You always try to pee before you swim, but sometimes your body defies logic and finds a way to refill your bladder just to spite you. Adrenaline and nerves wreak havoc on your system, and I knew tons of other swimmers that always, regardless of prior planning, had to pee right before a race. What to do if you’re desperate?
Read the whole thing here.
Words on the Word 
I’m learning to recognize the “pee dance” of my own kids and intervene when we are at the pool. Me: Are you sure you don’t have to pee? Daughter: Nah, I’m just doing this dance cuz I like to wiggle my butt.
🙂