Lex Fridman Podcast

Zach Bitter: Ultramarathon Running | Lex Fridman Podcast #205

Zach Bitter is an ultramarathon runner and coach. Please support this podcast by checking out our sponsors: - Ladder: https://ladderlife.com/lex - Belcampo: https://belcampo.com/lex and use code LEX to get 20% off first order - Noom: https://trynoom.com/lex - BetterHelp: https://betterhelp.com/lex to get 10% off EPISODE LINKS: Zach's Twitter: https://twitter.com/zbitter Zach's Instagram: https://www.instagram.com/zachbitter Zach's Website: https://zachbitter.com/ PODCAST INFO: Podcast website: https://lexfridman.com/podcast Apple Podcasts: https://apple.co/2lwqZIr Spotify: https://spoti.fi/2nEwCF8 RSS: https://lexfridman.com/feed/podcast/ Full episodes playlist: https://www.youtube.com/playlist?list=PLrAXtmErZgOdP_8GztsuKi9nrraNbKKp4 Clips playlist: https://www.youtube.com/playlist?list=PLrAXtmErZgOeciFP3CBCIEElOJeitOr41 OUTLINE: 0:00 - Introduction 1:58 - The marathon mentality 9:07 - The psychology of quitting 20:13 - Variety in ultramarathons 27:29 - What does it take to run 100 miles? 32:52 - Leading ultramarathon events 36:33 - Training and race strategy 39:03 - 100 Mile world record 43:05 - Foot strike variability and cadence 45:54 - The 11 hour barrier 49:21 - The most beautiful thing about running 55:43 - Zach's training regime 1:00:30 - MAF 180 Formula 1:10:55 - Training plans 1:25:54 - Marathons vs. 100 miles 1:34:55 - Zach's diet philosophy 1:49:43 - Fueling for race day 1:56:58 - Training while fasted 2:00:35 - Embracing the chaos 2:02:05 - 100-Mile treadmill WR 2:06:15 - The legend of Bert Kreischer 2:10:40 - The Transcontinental Run across America 2:28:15 - Who is the greatest endurance athlete of all time? 2:35:29 - Shoe technology in running 2:48:39 - Human limits 2:51:14 - Zach's biggest obstacles 2:54:58 - Advice for young people SOCIAL: - Twitter: https://twitter.com/lexfridman - LinkedIn: https://www.linkedin.com/in/lexfridman - Facebook: https://www.facebook.com/lexfridman - Instagram: https://www.instagram.com/lexfridman - Medium: https://medium.com/@lexfridman - Reddit: https://reddit.com/r/lexfridman - Support on Patreon: https://www.patreon.com/lexfridman

Lex FridmanhostZach Bitterguest

Jul 28, 20213h 1mWatch on YouTube ↗

WHAT IT’S REALLY ABOUT

Zach Bitter Explores Ultramarathon Suffering, Mindset, Nutrition, and Limits

Lex Fridman and ultramarathon world-record holder Zach Bitter dive deep into the mental and physical realities of running 100 miles and beyond, including Zach’s planned run across America. They explore how to manage negative thoughts, the psychology of quitting vs. never quitting, and why experience and perspective matter more than raw toughness alone. A large portion of the conversation focuses on training structure, maximum aerobic function (MAF), and how low-carb/carnivore-style nutrition can work—even at elite ultra distances. They also discuss technology’s impact on performance, from super-shoes to treadmills, and the broader philosophical meaning of suffering, improvement, and doing absurdly hard things.

IDEAS WORTH REMEMBERING

5 ideas

Expect—and plan for—the full spectrum of emotions in long efforts.

In a 100-miler you’ll cycle through highs, lows, doubt, euphoria, and nihilism; treating the first race as a full ‘data-gathering’ experience helps you learn your mental patterns so you can better manage them next time.

Use both “Goggins” and “Sam Harris” styles of self-talk selectively.

Sometimes you need a harsh, no-excuses internal drill sergeant; other times a calm, observational voice (“this too shall pass, give it another mile”) works better—effective athletes learn when to use each.

Zoom out when you feel like quitting and remember the big picture.

When the quit-voice shows up at mile 40 of 100, reframe it as throwing away months of work, not just the current 40 miles; pre-listing your deeper ‘whys’ gives you preloaded answers when doubt hits.

Build a massive aerobic base before chasing speed or specificity.

Bitter’s plans start with weeks of mostly easy, MAF-style running to strengthen the aerobic system with low injury risk, then layer in short intervals, tempo work, and race-pace long runs closer to the event.

MAF and perceived effort can guide sustainable, everyday training.

Using a simple formula like 180-minus-age as a heart-rate cap—then calibrating it with breathing and talking tests—lets many runners train frequently, recover well, and avoid burnout while still improving.

WORDS WORTH SAVING

5 quotes

A 100-miler almost feels like you’ve lived a full life in a day.

— Zach Bitter

Once you quit once, that quit pops up in your head a little sooner the next time.

— Zach Bitter

Running is something that has always been difficult for me, but I love it because it is difficult.

— Lex Fridman

If your motivation is to hold a record forever, you probably need to reassess why you’re doing this.

— Zach Bitter

You don’t want to make the thing you love so miserable that you can’t face it when it really matters.

— Zach Bitter

Mental landscape of ultramarathons: managing thoughts, demons, and quittingTraining philosophy: base-building, intervals, long runs, and MAF heart-rateNever quit vs. intelligent quitting: knowing when to push or step backLow-carb, keto, and carnivore-style nutrition for endurance performanceTechnology in running: super-shoes, treadmills, pacing, and record attemptsPlanning and training for a transcontinental run across the United StatesMeaning, joy, and art of running: from daily routines to world records

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