I have butt foam. Meaning, my butt makes foam. Like the foam on the top of a beer. Or is that froth? Do I foam or froth? Do semantics matter here?
It happens on my runs during the hot and humid season in Djibouti, which is from May through September. Temperatures range from 105-120 at all times of day and night. The heat index goes as high as 130. I’ve been running here for 12 years now and am pretty well adapted, as much as one can be, and don’t feel like I’m in a danger zone for heat stroke on these runs.
But still. What is going on back there?
I’ve always been a heavy, salty sweater. Could this be a factor? Or the fact that I don’t have a thyroid and so lack the ability to naturally regulate my body temperature?
When I google: “running foam” or “foaming runner” or anything about running and foaming, I get entries for foam rollers. Finally I tried, “exercise hot humid sweat body foam” and found a Runners World, 2001 article and an article about horses.
On one triathlon comment thread, someone responded to a question about foamy sweat with, “you may have rabies.” Not helpful. Also, most definitely not due to my laundry soap, as another suggested.
The Runners World article wasn’t very insightful. But the horse article says,
“White, foamy sweat is a by-product of over-strenuous work or being exercised in excessive heat. White sweat contains proteins, which take too long to dissipate to make an effective method of cooling the horse's body. While a small amount of white sweat can be present between the hind legs, on the neck by the reins or any other place where friction may occur, excessive white foam is a sign the horse is being over-worked.”
Friction and overworking in excessive heat. That sounds right. Bouncing butt + working hard + excessive heat = foam. Conclusion: I’m a horse.
Do you want to see photos of my foaming butt? I hesitate to show them. A friend recently heard me talking about my foaming butt and asked to see the photos.
“You don’t want to see,” I said.
“Mom, you have a nice sporty butt,” my teenage daughter said. “Show her the pictures.”
Well. If my teen thinks I have a, and I quote, “nice sporty” butt, I guess I can show the pictures.
Our bodies are bizarre and amazing, weird and disgusting. This is one of the strangest and grossest things I’ve discovered about my body. I used to feel embarrassed about it. I used to wipe my hands down my butt to remove the foam.
But you know what? It's the pandemic, and I’m going to own it.
I foam. It is gross and weird—and slightly awesome.
Read more Seven Months into the Pandemic essays.