Our home, the planet Earth, is a solid sphere (approximately) and spins around a relatively constant axis of rotation as it orbits a star we call "the Sun". Due to this rotation regions of the Earth's surface experience alternating periods of illumination, which we call "day", and periods of darkness, which we call "night". Earth's period of rotation is 24 hours. On average, 12 hours of day is followed by 12 hours of night. The exact division between day and night depends on latitude and on the position of Earth in its orbit around the Sun because Earth's axis of rotation is not perpendicular to its orbital plane, but is tilted by about 23.4 degrees. The hemisphere of Earth tilted towards the Sun experiences more daylight than the other hemisphere for half of an orbital period, or "year", and then this situation is reversed for the other half of the year. The hour is a human construct, but day and night are not. They are part of the nature of our world and affect all life on Earth.
Organisms tend to be more or less active during day or night or during the transition. Humans like you and me are mainly active during the day and rest at night. Human activities that last longer than 24 hours and don't involve jet propulsion may span an entire night. All this is to say that during my upcoming 100 mile trail run in September, which starts at sunrise and will, I expect, last 30 hours or more, I will necessarily be traveling on foot all night long. I will need to work against my normal circadian rhythm to eat, move, make decisions, and not sleep. I'm familiar with staying up after dark, have spent some late nights out on the town, and outdoors in wild forests and deserts. Marching all night on trails in the dark, however, is different. I'm lacking this kind of experience and didn't want the 100 miler to be the first time I tried to do it. Thanks to David Bitner, I've been aware of the opportunity to run overnight at Kettle Moraine. This summer I decided to try it.
The annual Kettle Moraine trail races in Wisconsin have distances of 100 miles, 100 kilometers, 50 kilometers, and a 38 mile "fun run" that starts at the 100 kilometer mark of the 100 mile course and shares a finish line with the 100 mile race. Runners can start the fun run any time after 5 p.m. Bitner and I started a little after 9 p.m., joining a 100 mile runner from his Minneapolis running club as dusk faded into night.
The fun run begins on rolling forest and prairie trails that are, in winter, part of an extensive Nordic ski trail system. The trails are sand and gravel and quite runnable. I saw fireflies and a few stars and enjoyed chatting with Bitner and Christianne, who was having a great 100 mile debut.
To illuminate the trail, I used two different lights. Around my waist I wore a 300 lumen Petzl TIKKA headlamp aimed at the ground about 10 yards ahead. I love that the headband of this lamp fits around my middle. On my head I wore a Black Diamond Sprinter 500 headlamp. I saw runners carrying more high-powered lights. The maximalist Kogalla RA system is popular with Kettle runners. My two small lamp system was perfectly fine. I don't need to run in artificial daylight, I only need to see the trail a few strides ahead. Both of my lights lasted 8 hours. At the Bear, where night will be 12 hours long, I will have extra AAA batteries in a drop bag out on the course.
The Kettle Moraine fun run has aid stations no further than 5 miles apart. In the spirit of simulating an overnight run at The Bear, where aid stations are separated by 7-9 miles, I wore my large running vest with two 0.5 liter soft bottles and carried a first aid kit, rain jacket, light gloves, change of socks, running poles, and some emergency rations. My plan was to eat well at aid stations, and try eating more than I usually do at night during races. I've recognized that I failed to eat enough at the end of my two 100 kilometer races, and that I absolutely have to keep fueling well past the 60 mile mark if I'm going to finish a 100 miler. I think I did a good job of this at Kettle. I snacked at Tamarack, 5 miles in. At Bluff I ate an entire hot dog with mustard and some cookies. At Highway 12 I had a quesadilla, watermelon, more cookies, and peanut M&Ms. Rice Lake, the turn-around point for the fun run, had the best food, and I indulged. I had a pulled pork slider with BBQ sauce, a piece of prime rib, and more watermelon and candy. This was at about 2 in the morning.
Halfway through the fun run, light drizzle turned into steady rain. I put on my rain jacket, unfolded my poles, and took off solo. Following Bitner and Christianne had been pretty easy and I wanted to test my mind and emotions. Would I be able to keep chugging through the night with no company and no pace setter? It was time to find out.
I increased my pace and was able to stay adequately warm without my jacket in spite of the rain for the next 4 hours. Every 30 minutes or so I would see light ahead through the trees and would slowly catch up to and pass a 100 mile runner and their pacer. Otherwise, I was alone on the trail. I continued to eat well at the aid stations, though it did get harder to stay committed to eating the same old junk food. Bluff had bacon, and coffee. I left that aid station with some of each.
It's a different world at night. This sentence is both cliché and true. The air and surfaces in the environment cool. Bird songs are replaced by frog calls. Human perception contracts and changes in quality. The acute color-perceiving cones of our eyes take a backseat and the wide-range grey-scale rods take over. I feel more conscious of sound in this state, aware of cracking sounds in the woods outside the range of my headlamps, hearing the murmurs of other runners or distant aid stations long before I encounter them. This is why humans love being up late at night on occasion. We leave the ordinary world of commerce and labor and enter a world of mystery and spirits. It is a mind-altering experience.
30 minutes before dawn I stumbled going down a little hill, rolled my right ankle, and fell sprawling head first on the trail. I was fortunate to not fall on and snap one of my ultralight poles or injure myself any worse. After a few minutes of walking, I was able to restart running, but more slowly than before the fall and needed to put my jacket back on in order to stay warm. That was the only misfortune of my fun run. I had no regrets about eating a lot, no problems with gear. I ran the second half of the fun run 40 minutes faster than the first half.
Running all night was fun and a useful experience. I'm feeling more prepared for my own first 100 mile run.