Special Report: The Pool and the Urge to Pee

It never fails. By the time I get from the pool and to the locker room, I am nearly peeing in my pants. Er ... swimsuit. Even if I use the toilet right before swimming, there is still an uncontrollable urge to pee afterward. I've wondered to myself, "Self, what is this about? Am I unknowingly swallowing lots of pool water? Is the water seeping through my skin and straight to my bladder? Are my ear canals connected to my pee parts?"

So, I used the mighty Internets to find some sort of explanation for this phenomenon. I even asked my med school almost-doctor friend if this is true, and he affirmed. Get ready - Triathablog is about to go scientific on your asses.

"For those of you who are aware of ANP (atrial natriuretic peptide), you may know that ANP is released as a result of the muscle cells (myocytes) of the right atria (part of your heart) in response to their being stretched. As a result, ANP helps to rid the body of salt (sodium specifically) and as a result, decrease the body's water (since water follows salt-osmosis), subsequently lowering one's blood pressure by making you pee out sodium and water. What you may not know is that there is a link between stretch receptors in your neck and ANP being released. Thus, even if you woke up early in the morning, peed in the toilet, and got in the shower, after a while of being in the shower with the water massaging your neck, you'll feel the need to pee again. Similarly, if you're in a swimming pool, ocean, lake, etc. up to your neck, you'll notice after a little while the urge to pee." - The Internets

So, there you have it. Those crazy atrial natriuretic peptides are the culprit for my pee dance all the way to the shower. Did I say shower? I meant, toilet. I never pee in the shower - what are you talking about? Gross. (Okay, maybe I do. But at least it's not the pool).