David Raichlen is a professor of biological sciences at the University of Southern California whose research examines how human evolution, physical activity, and brain health are linked across the lifespan. In this conversation, Zoë and Brendan talk with David about what's actually happening in your brain when you go from couch to consistently active, why exercise might be the closest thing we have to a dementia preventative, and why his research on the runner's high, which famously involved humans, dogs, and ferrets, suggests it evolved as something more useful than feeling good.

They also get into what hunter-gatherers like the Hadza can (and can't) tell us about how to live, why "more is better" hits diminishing returns at the high end, the trouble with paleo prescriptions, and whether sitting really is the new smoking. Plus: Brendan tries to figure out if his rock-climbing mom or his golfing dad is doing better cognitive work than he is.

This episode is brought to you by Running Warehouse, the one-stop shop for all things trail running, with gear guides and expert resources to help you figure out what actually works for you. Use code TRAILHEAD for free two-day shipping on orders over $50.

Our featured race is the Sonoma Fall Classic, the inaugural fall festival in the heart of California wine country featuring a 100-miler, the original Lake Sonoma 50 returning to its 2008 point-to-point roots from South Lake Trailhead, a trail marathon, and four-person relays. Sixteen miles of buttery single track, sweeping lake views, swimmable water crossings, and free on-site camping. Registration closes Monday, October 12. Sign up at UltraSignup.com.

The Trailhead is part of the UltraSignup Podcast Network.

Rochelle Bilow is a romance novelist, food writer, French Culinary Institute graduate, former Bon Appétit editor, and current kitchen gear expert at Serious Eats, and she just came back to ultrarunning after nearly a decade away from the sport. In this conversation, Zoë and Brendan talk with Rochelle about what she learned cooking on a farm that culinary school never taught her, why she pivoted from heartbreak memoir to romance fiction, and what it's like to balance writing deadlines with ultra training (her answer: ask for a deadline extension).

They dig into why romance as a genre gets unfairly dismissed, what makes a great enemies-to-lovers arc, and the trail running romance novel she's currently writing. Plus: the $400 toaster that changed Rochelle's life, the truth about toaster oven air fryers, and the only correct way to clean a cloudy Vitamix.

This episode is brought to you by LMNT. Stay on top of your electrolytes all day, not just on the run. Grab a free sample pack with any order at drinklmnt.com/UltraSignup.

Featured Race: Booneville Backroads Ultra — 10K to 100 miles through the Bridges of Madison County countryside in rural Iowa. New for 2026: a fully marked course and crew support allowed. Trail Sisters members can DM the race for a discount code. Race day is September 5th, registration closes August 28th. Sign up at UltraSignup.com.

The Trailhead is part of the UltraSignup Podcast Network.

Ryan Goodman grew up on a cattle ranch in Arkansas, studied beef cattle science at Oklahoma State University, and now manages WSU's beef cattle research program as Beef Cattle Operations Manager in Pullman, Washington, where he also teaches hands-on lab courses to the next generation of pre-veterinary students. Online, he goes by @BeefRunner. He also runs a lot of 100-mile races.

In this conversation, Zoë and Brendan talk with Ryan about what six weeks of calving season: sleepless, high-stakes, completely indifferent to your training plan, taught him about finishing a hundred-miler, and why "one thing at a time" works as well in the Crazy Mountains of Montana as it does on a ranch at 2 a.m. They get into the complicated but more negotiable than you'd think relationship between ranchers and trail runners, the farm-versus-ranch distinction (I-35 is the line, roughly), why the heifers following you on BLM trail are curious not threatening, and Red Dirt music as the ultrarunning soundtrack you didn't know you needed. Also: cow tipping, the correct post-ultra meal, and whether Pullman counts as a town.

This week's featured race is Mujeres and Marigolds, a women's only event with a 5k, 10k, 25k, 50k, and 100k relay!

Thanks to TrailCon for supporting the podcast. Register now to attend!

C. Thi Nguyen is a philosopher at the University of Utah, a former food writer for the Los Angeles Times, a rock climber, and one of the world's leading thinkers on the philosophy of games. His new book, The Score: How to Stop Playing Somebody Else's Game, argues that games are the defining art form of our era, and that the scoring systems that make them so joyful turn quietly destructive when institutions and apps wield them instead. In this conversation, Zoë and Brendan talk with CT about why ultrarunning is a game in the deepest philosophical sense, his concept of value capture and why it explains your relationship with Strava better than you'd like, what carbon plates and trekking poles reveal about game design, and why Bernard Suits, the philosopher who defined play as "voluntarily taking on unnecessary obstacles", thought games might literally be the meaning of life. Also: fly fishing pickup artists, the shot clock, elite yo-yoing, and Zoë's Smash Mouth Strava segment situation.

This episode is brought to you by Running Warehouse, the best place to find shoes, kit, and gear from top brands, with honest reviews and filters that actually help.

Our featured race is the Baker Trail Ultra Challenge, a 50-mile point-to-point through the Cook Forest stretches of the North Country Trail in Western Pennsylvania with 6,200 feet of climbing and a three-part commemorative medal — complete all three sections and you get the full set. Registration closes August 28. Sign up at UltraSignup.com.

The Trailhead is part of the UltraSignup Podcast Network.

Pavel Cenkl is a climate writer, ultrarunner, and Dean of Academics at Prescott College who has run hundreds of miles across Iceland, Scandinavia, and the Arctic through his project Climate Run. He grew up in the White Mountains, worked the AMC huts, started one of the first collegiate trail running teams in the U.S., and built a master's program combining movement, environmental philosophy, and ecology.

In this conversation, Zoë and Brendan talk with Pavel about what happens when you push yourself to the edge of exhaustion in landscapes that are literally shifting beneath your feet — disappearing glaciers, the vulnerability of being utterly alone in midnight sun, why "resilience over resistance" is a better framework for running and life, and the moment he screamed so loud on day three of his Iceland crossing that he scared a goose into flight and accidentally had a paradigm shift.

This episode is brought to you by Precision Fuel and Hydration, use code TRAILHEAD26 for 15% off at PrecisionHydration.com.

Our featured race is the White Lake Ultras on May 2nd in Tamworth, New Hampshire, a two-mile lakefront loop where you pick your poison: 6, 12, or 24 hours. Costumes encouraged. Register at UltraSignup.com.

The Trailhead is part of the UltraSignup Podcast Network.

Christie Aschwanden is a New York Times bestselling author, former lead science writer at FiveThirtyEight, and one of the sharpest science journalists working today. She's also a former elite Nordic skier for Team Rossignol and a national collegiate cycling champion, so when she set out to investigate the multibillion-dollar recovery industry for her book Good to Go, she brought both a scientist's rigor and an athlete's bullshit detector.

In this episode, Zoë and Brendan talk to Christie about why cold plunges might actually delay your recovery, how your sleep tracker could be making your sleep worse, and why the most effective recovery strategies are boring, cheap, and unsexy. They dig into the rise of the "recovery industrial complex", from Tom Brady's infrared pajamas to cryotherapy chambers that NBA teams bought just because other teams had one, and what the research actually says about inflammation, ibuprofen, HRV, and the post-workout "window" myth.

Christie also makes a compelling case for radical acceptance, situational awareness for your body, and trusting your own perceptions over your Garmin readiness score. Plus: the beer mile, knitting as recovery, and why pizza might be the most underrated performance fuel.

Brad Stulberg co-wrote Peak Performance with Steve Magness and has spent over a decade studying what excellence actually requires. He joins Zoë and Brendan to dismantle the myths of hustle culture and explain why genuine excellence isn't about optimization, it's about caring deeply about something worthwhile. We dig into "zombie burnout" (exhaustion from doing too little of what lights you up), what Brad learned from studying Courtney Dauwalter and powerlifter Layne Norton, and why chasing flow states prevents you from experiencing them. A grounded, research-backed conversation about pursuing excellence without losing yourself.

Brad Stulberg is the author of The Way of Excellence, Master of Change, and The Practice of Groundedness. He's on faculty at the University of Michigan and hosts the podcast Excellence, actually.

Sponsor: This episode is brought to you by LMNT—electrolytes with no sugar, no BS. Try their chocolate flavors heated up for the ultimate winter hydration hack. Get a free sample pack with any order at drinklmnt.com/ultrasignup.

Featured Race: The Devil Makes Three 50k and 10 Miler — May 16th in Waxhaw, North Carolina. Technical singletrack, prairie grass, lake views, generous cutoffs, and a low entry fee because trail running should be accessible. Cupless race, so bring your own hydration. Registration closes May 13th at ultrasignup.com.

What happens when you strip away sleep, ego, and every external measure of success for 330 kilometers? Doug Mayer, founder of Run the Alps, former Car Talk producer, and three-time Tour de Géants finisher, has spent years trying to answer that question.

His new graphic novel, Last of the Giants, is his best attempt yet. In this episode, Doug joins Zoë and Brendan to talk about leaving a 25-year career in radio to build a trail running tour company in Chamonix, why he kept going back to one of the world's most grueling ultramarathons, and how he translated the experience of hallucinating in a snowstorm at 3am into a visual story. He shares what he learned from interviewing neuroscientists, a Buddhist monk who specializes in suffering, and the world's leading expert on pilgrimages, all in service of understanding why we do hard things and what we bring back from them. The conversation touches on "meeting the dragon" (a Buddhist concept for the moment when your usual tools stop working), the hero's journey, why Tour de Géants feels like "the PhD of ultrarunning," and how Doug accidentally started dating someone mid-race because her prefrontal cortex was too exhausted to know better.

Links: • Last of the Giants by Doug Mayer, available at Bookshop.org, Amazon, and wherever books are sold

•Run the Alps – trail running tours in the European Alps

•Running Warehouse – gear guides and the Salomon Genesis

•Salt Lake Foothills Trail Races – May 30, 2026 (10k, half, 50k, 50 miler) More from UltraSignup Podcasts:

•The Buzz with Buzz Burrell – deep dives into ultrarunning culture and philosophy

•Between Two Pines – A trail running podcast that doesn't take itself too seriously