By signing up for a 100-kilometer race, you’re making a proclamation: you’re ready to go big. The 100K distance is often considered the “gateway” to the 100-miler. But even if you don’t intend to go farther, you’re still going to put in some work. For many runners, this will be the first time you’ve intentionally committed to running after dark, and it’s a big step.

We connected with a few of our favorite coaches and asked them to share their best 100K training advice to better prepare you for the big dance. Regardless of whether you’re a first-timer hoping for a happy finish or an experienced pro going for a shiny PR, we’re confident we’ve got some good tidbits to get you to that starting line healthy, happy, and ready to race.

On this episode of The Trailhead, Corrine and Buzz dive into safety and mandatory gear lists. They may seem overwhelming, especially depending on the country you’re racing in, but will you ever regret following them?

Then, Corrine talks to Jen Sotolongo and Marta Fisher about the Women Who FKT project, which has inspired and encouraged more runners to set out on their own fastest known time adventures. You can read Jen’s piece and some real FKT-er’s stories on UltraSignup News.

Then, Buzz speaks to Jacob about an upcoming journey run that John Muir would be proud of, and to Laura about making the leap from 100 kilometers to 100 miles.

The Trailhead Podcast is a production from UltraSignup News. This episode is presented by Sidas, your foot company. Use promo code “BOGOSOCKS” to get two pairs of running socks for the price of one at us.Sidas.com.

The foot-sock-insole-shoe interface is an important, but often overlooked concept for many runners. It’s important to have the correct shoe for your needs, but without stability and support inside the shoe, your foot can quickly fatigue causing injury. Sidas 3Feet running insoles support and protect the feet while promoting natural motion stride after stride. The integrated grip yarn zones on Sidas Run Feel and Trail Protect socks interface with the insole to stabilize the foot and reduce movement inside the shoe.

Together, Sidas Run Products take care of your feet so you don’t have to worry about them on the trail. Learn more about Sidas running socks and insoles and get 20% off your order when you use code trailhead20 at checkout. 

🥶 Frozen Fast: Can you freeze the biological clock or do you have to get slower as you age? Alex Hutchinson writes about the curious case of coach Alan Couzens’s Immortality Quotient and whether the aging process is an inevitable slide into decrepitude or the result of not getting enough exercise.

🎥 Video of the Week: Have you pushed this hard at the end of an ultra?

👟 Worth It? A pair of Air Jordans from the 1998 NBA Finals just sold at auction for a record $2.2 million dollars. (Hit reply and let us know how much you think Kílian Jornet’s shoes from his first UTMB victory would go for at Sotheby’s.)

✈️ Airport Segments: Despite sunglasses-inside-guy claiming a segment that he didn’t actually get the fastest time on, he did open our eyes to Strava segments at airports, because… who doesn’t want to be more sweaty on their next flight. ⬆️

🥸 Another Rosie Ruiz? Rosie won the 1980 Boston Marathon, dawned the olive wreath, and gave television interviews before they figured out she’d cut the course for her victory. On April 7th, Scottish-Based Ultrarunner Joasia Zakrzewski was found to have ridden in a car during the GB Ultras Manchester to Liverpool 50-mile race. 

👣 Trail Runners Save the World (Again): Wanna help save the world? Apply to attend the Footprints Running Camp for a chance to be part of the solution to the climate crisis. Read Meaghen Brown’s lovely piece for Patagonia, then watch this video, and apply.

🏔️ Caved Out, Zenned Out: Would you spend 500 days in a cave for science? Beatriz Flamini read 60 books and said, “I didn’t want to come out.”

➡️ Lastly, here’s what we’re reading, watching, and listening to this week.