fbpx Skip to main content

Zach Bitter on Heart Rate Running, Nutrition and Mindsets

By September 12, 2019May 20th, 20232 Comments
zach bitter running
Zach Bitter (Strava | IG | Twitter) recently set the new 100-mile (161km) running World Record in 11 hours and 19 minutes. He averaged 6:48 min / mile = 4:13 min / km and beat the previous world record by 9 minutes! That’s about four sub 3 hour marathons in a row!! ⁣He then continued running another 4.88 miles to run the 12 hours World Record as well.
In the past 10 years Zach Bitter ran more than 50,000 miles = 80,467km. Using performance as his compass, he learned a lot over the years of what works well for him.
He is an absolute fat burning machine and I was thrilled to interview Zach for The Extramilest Show. We take a deep dive into heart rate training, nutrition, mindsets and much more.

Big THANK YOU to Zach Bitter for taking the time to share his insights!

🚨BIG CONTEST TO WIN RUNNING SHOES! What was your favorite quote or takeaway from this episode? I would love to hear from you in the comments on YouTube. 1 random winner gets a pair of Altra shoes of your choice. (Zach Bitter and I both run in Altras) Comment to enter here🚨

Watch this full interview on YouTube.

Listen to the conversation on Apple PodcastsSpotifyOvercastStitcher or your other favorite podcast platform.

Extramilest show on Apple Podcasts

Find out more about Zach Bitter here:


  • Brief background as a runner [3:42]
  • His first ultra running experience [7:02]
  • How Zach Bitter first got into HR training and how he integrates it in his training [9:22]
  • How to figure out your correct heart rate training zone, more specific than the 180 formula alone.  [11:02]
  • How Zach Bitter trains for his different races [16:07]
  • Zach’s preparing specifically for this World Record run [21:22]
  • Importance of positive mindsets during races [26:22]
  • Looking at HR vs looking at pace [27:32]
  • How does Zach Bitter overcome though spots in training and racing [29:22]
  • Benefit of Zach training in a lot of heat in Arizona [35:22]
  • His race hydration and nutritional approach on race day [36:52]
  • Running 4 sub 3 hour marathons back to back [41:22]
  • Zach Bitter’s approach with high fat, low carb, ketosis and carb intake [42:22]
  • How do you find the minimum dose of carbs to perform well? [46:00]
  • How would Zach change his nutritional approach if he would race at higher intensity [50:10]
  • How Zach limits his injuries risks [54:20]
  • Improving tight calves [1:00:10]
  • The importance of consistency and the right training approach [1:01:50]
  • Shoes Zach’s runs in are Altra running shoe [1:04:20]
  • Running watch, Zach Bitter uses the COROS Apex [1:06:05]
  • Zach’s coaching calls for problem solving [1:09:47] 
  • About the Human Performance Outliers podcast Zach co-hosts [1:10:52]

Products / videos / people mentioned:

You can find me, Floris Gierman here:



  • Csaba Burillak says:

    I have Altra Lone Peak 3.5 trail shoes and I like them, too.

  • Csaba Burillak says:

    Fantastic show as always! Thanks, Floris, nice to be part of the Extramilest community! Zach deserved to become the world record holder of the 100 mile, great athlete achieving great results by the training of several years. I listened to many of his videos explaining his training and nutritional strategy.
    I like Zach’s approach in ultra races emphasizing the positive mindset as well as conciously setting a range of minimum and maximum pace where he should range in order to get home safe on the particular ditance.
    I was glad to hear that he considers optical heart rate monitors as quite accurate because I like my Polar Vantage M very much and I think the only kind of issue is the delay of showing the actual HR, otherwise it’s very accurate. I had many problems with chest straps, I’m quite happy with the change.
    Excellent job, Floris, thanks a lot, looking forward what Lewis says about wrist based heart rate monitors. :-)

Leave a Reply