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Varying degrees of difficulty

Varying degrees of difficulty

Article by: Michael Selman

Reproduced with permission of the author

In the hot Georgia summers, the common phrase is "It's not so much the heat, but the humidity." Though the temperatures rarely go above the lower 90's, other meteorological numbers, such as dew points and relative humidity (I think they are somehow related) are thrown in to create something called The Heat Index. This is summer's way of suggesting that we forget the actual temperature, because THIS is how hot it really feels. The Heat Index in summer often checks in at over 100.

The wind chill factor is to winter what the heat index is to summer. Usually, we pretty much escape winter's clutches in these parts, but this year, we have already had more than our share of the types of white stuff, and cold stuff usually reserved for the cities we relocated here from. Alberta has been very busy sending its clippers our way, and the hardy among us have dusted off the polypropylene and Gor-tex in order to keep the show outdoors.

Both the Heat Index and the Wind Chill Factor are supposed to tell us how hot or cold you're going to feel when you're in it. But there is a third index that the runner knows all to well. Experts say that running adds about 30 degrees of additional warmth to whatever the temperature would feel like standing still. That means that running in summer's mid-day heat, while the heat index is 100 is going to make it feel like 130. But in the winter, a nippy wind chill of 25 will feel like the mid 50's, quite pleasant for running. It's the Runner Temperature Index, or how hot or cold a runner feels in the midst of a run. In the winter, it's a blessing, and in the summer, it's a curse.

Winter is usually my favorite season to run, and this year has been no exception, but it has been more of a challenge than usual. The cold weather, and stiff breezes have seen actual temperatures often dipping to the teens, with wind chills below zero. December 30, 2000 was a particularly memorable run.

I woke up early, and couldn't go back to sleep that morning, so I decided to get out of bed and go for a run while it was still dark. I turned on the weather channel to get the scoop. The actual temperature was 17 degrees, and the winds were blowing at close to 30 miles per hour. That made the Wind Chill Factor -16, the coldest I could ever remember here. I did the math. That 30 degree cushion was going to warm me up to a sweltering 14 degrees.

I dressed warmly, putting a sweatshirt over a polypropylene undershell, and topped it off with a Gor-Tex top. On the bottom, I wore thick winter tights, and Gor-Tex pants. Finally, I topped it off with a wool hat, and a pair of Thor-lo socks as mittens. I left my watch at home, as this was not a run for speed. The only exposed spot on my body was my face.

I took a deep breath, and stepped out the door. I could feel my beard, moustache, and nose hair immediately crystallize with my first breath. I suddenly felt like I was bonding with people living in Fargo. This was totally nuts, but I never for a moment thought about turning around and going back in the house.

As I started running, my cheeks felt like they were tightening up and freezing solid. I was hoping that the "Runner Heat Index" would kick in before the frostbite did. After a mile or so, I could feel my cheeks slowly and slightly thawing, and I actually started sweating under the many layers. But the sweat from my brow didn't go very far, as it started forming little icicles on my eyelashes. The Gor-tex was doing a good job of breaking the brisk wind, and I actually started to enjoy the fact that I was overcoming the elements after the first couple of miles. But at the same time, I was happy and relieved to be back in the house, once the run was over.

The next morning, the last morning of the year 2000, I was out early again. The actual temperature was only one degree higher than the day before, but the winds were calm. That put the Runner Heat Index in the mid 40's, and the run was comfortable from the first step. It was only a one-degree change in actual temperature, but an exponential difference in the degree of difficulty from one run to the next.

The wind chill factor is the true indicator of how you should dress in winter. If the wind chill dips below zero, take it very seriously, and dress for the chill, not the actual temperature. If it's windy, wear a windproof outer shell, and leave as little exposed skin as possible. It's the exposed areas that will feel the teeth of the wind, as I found out in December 30th. Trust me, I'm in no hurry for summer to be here. But if winter backed off just a little bit, you wouldn't see me complaining.

Michael Selman
Roads Scholar
Atlanta Georgia USA
Michael Selman is a freelance writer who has appeared in publications and web sites throughout the world, including Runner's World, Footnotes, and CoolRunning.

Michael has published many other articles on running and his personal experiences in the Thoughts of a Roads Scholar. Feel free to E-mail him at

This page last updated: Saturday 20 March 2010

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