Running Through the Night? Here’s What You’ll Need (sponsored by Petzl)

Running through the night is one of my favorite aspects of running long ultras.

It’s a rare occasion that I spend hours traversing trails in the dark, so when the chance presents itself, I relish it all—the crisp air, the distinctive variety of peace and quiet in the woods at night, the simple pleasures of arriving at an aid station to decorative lights, a campfire and cheerful volunteers dishing up quesadillas at 3 a.m.

But nighttime running—especially in the middle of an already epic endurance effort—comes with its own unique set of challenges, not the least of which is choosing the right gear for the task. If you have an upcoming ultramarathon that will take you beyond daylight hours, here are a few key things to keep in mind.

Choose Your Lighting Wisely

One of the most important gear decisions you’ll need to make ahead of time is choosing a good headlamp for the night portion(s) of your race. Unfortunately, there’s no one-headlamp-fits-all solution for ultrarunning, since a number of factors play into which light will work best for you and your target race. You’ll want to strike the right balance between brightness, battery life and weight.

Generally speaking, I’m willing to wear a slightly heavier headlamp in exchange for a brighter beam. I can’t tell you how many times I’ve flown past runners with dull headlamp beams, slowing picking their way through the woods. On more than one occasion, someone has called out after me, “How can you run so fast in the dark?!”

I assure you it has nothing to do with my lung capacity; it’s because I wear a headlamp so stupidly bright it feels as if I’m not running in the dark at all.

That said, here are a few things to take into consideration when choosing the right headlamp for your race:

• How technical are the trails? The more rugged they are, the brighter a headlamp you’ll want.
• How shaded are the trails? You can get away with a lighter, less powerful headlamp in the Arizona desert than in the dense forests of the Pacific Northwest.
• Which phase will the moon be in during your race, and what’s the weather forecast? A clear sky with a full moon might let you get away with a lighter light than an overcast or moonless night.

*Pro Tip: Pack a spare headlamp or mini flashlight, just in case. Nothing will slow you down more, if not put the kibosh altogether on your race, than getting unexpectedly caught in the dark without a light. Also, unless you’re running a course with multiple, short loops that take you past a personal gear stash or drop bag regularly, I advise against stowing your only headlamp in a drop bag along the course. Long ultras are notoriously unpredictable and there’s a decent chance you won’t reach that drop bag at the time you hope or expect to. And, especially if you’re running in dense woods, the trail may grow dark and difficult to see earlier than you expect.

Master the Art of the Battery

Headlamp manufacturers’ specs include a variety of factors, such as lumens, beam distance and battery run-time—the latter often broken up into separate categories for low-, mid- or high-output, depending on what setting you use.

The battery run-time spec is based on how long a headlamp can produce “usable light”—a significantly dimmer level of light than any given headlamp will producewith fresh batteries. In most headlamps, regardless of stated battery run-time, beam distance tends to decrease rapidly after a few hours of use. This is no biggie if I’m reading a book in my tent, but for running on technical trails, I find it’s worth swapping out my batteries for fresh ones once the decrease in beam distance becomes noticeable.

You can conserve your headlamp’s batteries by switching your headlamp to a lower beam setting—or even, sometimes, off entirely—whenever possible. (I did this for some stretches of the 2015 Ultra-Trail du Mont-Blanc, during relatively non-technical stretches above timberline when the light of the full moon reflected off surrounding glaciers.) A few Petzl headlamps, including the perennial ultrarunner favorite Nao, offer a “reactive lighting” setting that automatically does such battery-conserving gymnastics for you.

Always pack spare batteries, especially if your race occurs during winter, early spring or late fall, when nighttime hours last longest. If you’ll be running through a full night or more, be wary of rechargeable headlamps, which often don’t have the option to swap in fresh batteries mid-race.

Pro Tip: Not all batteries are created equal. Always consult your headlamp manufacturer’s battery specs first and foremost, but generally speaking, lithium batteries are a better choice for ultrarunners than alkaline. Though they cost a bit more, lithium batteries weigh less, work longer with more consistent output, and hold up better in cold weather—all boons in an ultra.

Pack a Few Clothing Accessories for the Night

Naturally, your apparel choices will depend largely on the climate and weather forecast of your race. Take a gander at the average high and low temperatures for your race’s environs. Keep in mind that temperatures may fall considerably if the race course climbs in elevation overnight.

I find that as long as I continue moving at a relatively steady clip through the night, my body tends to keep its core temperature well regulated. However, certain extremities can grow chilled in the cool night air, especially my hands, arms and ears.

Here are a few accessories I like to have for the night stretches:

• Arm sleeves
• Lightweight beanie or warm cap
• Buff or comparable neck gaiter
• Lightweight pair of fleece gloves, or spare pair of socks that could be worn as mittens in a pinch
• Packet of air-activated handwarmers or toewarmers, just in case

Pro Tip: Tucking an emergency blanket into your pack is not a bad idea for any ultra—least of all in case you get uncontrollably sleepy on a stretch between aid stations and need to take a power nap on the side of the trail. In the middle of the night during my first 100-miler, I gave the emergency blanket in my pack to a runner I came upon who was exhausted and experiencing the early stages of hypothermia.

Practice Makes Perfect

Ever heard the old adage “Never try anything new on race day”? Well, it applies to night running as much as to any other aspect of our sport. If your headlamp is new, make sure it provides enough light to run trails confidently in the dark. Familiarize yourself with its user guide ahead of time. Practice adjusting the fit and changing its batteries; you’re likely to need to do both sometime during your race.

In addition to testing out and honing your gear choices, it’s wise to gain confidence ahead of time navigating trails in the dark, and also get more comfortable with the sleep deprivation that frequently accompanies overnight runs.

Here are a few great ways to do so:

• Run a night trail race
• Pace someone through the night at a 100-miler or other long ultra
• Organize a post-dusk or pre-dawn social run with friends
• If you plan to use a pacer or two at your race, invite them out for a long nighttime training run with you

Pro Tip: Pack a small tube of anti-chafe product such as BodyGlide or 2Toms SportShield. Aside from being a great idea in general for ultras, it can be helpful in the (hopefully rare) event that the skin on your forehead gets a bit raw after hours of wearing a headlamp.