Let me share an interesting bit of physics that occurred to me as I was wrapping up my run, a run that started with me deciding that I'd have a better/safer run on the roads than trudging through virgin snow on the trails.
As I rounded the last corner and finished off the run in the office parking lot, I noticed that my feet were wet. Really wet.
That's not the interesting part.
It was 14F outside. No sun. And the parking lot, as well as many of the roads I had just run on, were wet. There were even puddles.
Water freezes at 32F. That's what we call ice. Yet at 14F, there was still water.
That's the water-phase-changing magic of salt. Salt lowers the freezing point of water. That's why it's spread on roads and parking lots. No ice, no slipping, everyone's safe. Still that the interesting part.
Here's the interesting part. The water in those puddles, and on the road, and in the parking lot, and all over my feet, is also 14F.
My tissues aren't full of salt water, just plain water. The kind of water that freezes at 32F.
We all know what's coming, right?
Yep, I got a touch of frost bite today. After dozens of bitterly cold runs last winter, and several already this winter, runs in which I returned safely with numb but yet unfrozen skin, today I wasn't so lucky.
It wasn't until mid-afternoon that I knew anything was even wrong. Tips of a couple toes stung a bit when I walked around the office. Something was definitely up. And it wasn't a good something.
When I got home, I took my socks off to find the tips of three toes sporting big honkin' blisters. I'd feared they'd be black and half falling off, so blisters were a relief. (I thought about posting a picture, but really, who wants to look at blistery toes? No one.)
The internet, the digital age's free clinic, guided me to this page, which told me to dip my piggies in warm water, and keep them there. It's been a couple hours, and 2 warm-ups, and they feel better already.
I was only out for about 30 minutes. I've been out longer in colder temperatures. But the combination of frigid temps and salted water sucked the heat right out of my toes.
So, it will be conventional shoes for a few days. And socks. Thick socks.
I got lucky. I'd grown complacent and careless. Numb toes were nothing new. But, that numbness can hide more serious problems. Don't ignore numb toes. Or numb anythings, for that matter.
Numbers: 4.0 miles, and, you know, the frostbite.