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Who is Zach Bitter? (Training, Diet and Running World Records)

Who is Zach Bitter? (Training, Diet and Running World Records)

Let’s admit it, Zach Bitter is on FIRE! He’s been around for quite some time but it appears he has found yet another level of greatness. Maybe it’s just the accumulation of all those years of hard work, but he’s doing something right. I’ll admit that for me it took awhile to get really interested in his story.

Living in the mountains of Montana and now in Bend, Oregon, my interests have always naturally gravitated towards the mountain athletes, the guys who train in the mountains and do well on the terrain that I enjoy running on.

But Zach’s name kept on popping up and when I saw his name scrolling through Joe Rogan’s podcast episodes, it was a sign, I could no longer ignore this guy.

What I learned from that podcast was that (1) Zach is a straight up beast, and (2) he doesn’t leave anything up to chance, he’s meticulous in his preparation, and he’s not afraid to integrate new ideas and philosophies into his training. In short, he’s a trailblazer and we’d be wise to listen to what he has to say.

If you aren’t familiar, Bitter’s most prominent achievement is his 100 mile world record (WR) of 11 hours, 19 minutes and 13 seconds, which he set in August of 2019 at the Six Days in the Dome event in Milwaukee, Wisconsin. He averaged…wait for it…6 minutes and 48 seconds per mile [insert one thousand head-exploding emojis here].

Yet as if that wasn’t enough, Bitter continued to run so he could set the 12-hour world record of 104.8 miles. Through this singular achievement, Bitter thrust himself into the highest echelons of the sport. The 100 mile distance has a strong history so the record was well-established and very competitive. Zach deserved all the publicity and recognition he received.

And then just recently, on May 16, 2020, Zach set the 100 mile treadmill world record in 12 hours, 9 minutes and 15 seconds. He jumped back and forth between two NordicTrack X22i treadmills because they timed out every couple hours. He took a few bathroom breaks and even a full two minute mental break at mile 87 to gather himself.

You can watch the full live stream—yup, all 12 hours on YouTube. Here’s the morning…


…and here’s the afternoon session:


Zach Bitter’s Training Philosophy

In my research, I can’t say that Zach’s training is too out of the ordinary. What’s out of the ordinary is his diet and nutrition, which we tackle below. For training, he’s a big proponent of specificity, tailoring his training to the elements he’ll see on race day. He comes fully prepared to his races having mimicked the course/environment/terrain/conditions multiple times in training.

For example, in preparation for his track races, Zach will do a lot of weekly mileage on hard surfaces, the road or the track. He is also diligent in preparing those unique muscles that are only really triggered when leaning into a track turn.

Zach says he likes to keep things fresh by dedicating the first half of his year to more mountainous trail running experiences and then shift to flatter more runnable races during the second half of the year. For example, in 2019, he started out with the San Diego 100 (1st place) and then the legendary Spartathlon, which is a road race in Greece.

But apparently he likes to keep things flexible because he ended up getting distracted by the 100 mile WR attempt, which was just fives weeks before Spartathalon.

Bitter does run quite high weekly mileage. Before his world record on the track, he ran a solid four-week block that included 129.4, 150.1, 72.2 and 150.2. Read his full write-up on preparing for the race here:

Another major element of Bitter’s training seems to be the practice of negative splitting his long runs. By that, I mean he ran the second half of each of his long runs faster than the first half. You can imagine how difficult that could be. As we fatigue and deplete our resources, most runners experience a drop-off in pace during the second half of a road or ultra marathon, but not Zach.

He prepared his body to know that it was go time when things got tough. Come race day, he taps into that muscle memory and is able to ramp up the pace when most others are starting to fade.

Zach’s Coaching Services

If you want to hire someone with a massive base of experience, and who will take an analytical approach to your training, Zach might be your guy. After reading many of his blog posts, I get the feeling that he’s a great motivator, someone who has developed a strong mental approach to the sport, but also leans into the science and the WHY behind what he does.

Prior to making his career out of running and coaching, Zach was a high school teacher, so he knows a thing or two about flipping light bulbs and helping people walk through the learning process. And then, of course, from what I can tell he seems like a super nice guy who’d be a real pleasure to work with.

Zach offers a couple services through is website ( First, he offers 30 and 60 minute consultations, which you can sign up for via a portal and a few clicks. They are $40 for 30 minutes and $75 for 60 minutes. Depending on your experience level, this might be very valuable to you if you want to dive into a few key topics but don’t need all the highly detailed training programs.

You could use a consultation to ask him about specific events such as Six Days in the Dome, nutrition advice, training philosophies, or anything else under the sun.

Next, you can email Zach at to inquire about his full blown coaching services where he offers basic to advanced plans and services.

Also read:

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Zach Bitter’s Diet

Many of you may have found yourself here for this topic alone. How does a man fuel his body to run 6:48 pace for 100 miles? Well, he follows the low-carb high-fat diet. He’s not full-blown ketogenic, but integrates phases where he’s close. He made this diet switch after dealing with poor sleep, wild energy level swings, and lower leg inflammation.

He credits Jeff Volek M.D., P.H.D. as his key influencer. As a result, Zach says he’s become so efficient at burning fat that he could cut his caloric intake during a race by half. He says that even really skinny runners, who have 4-5% body fat, can (if adapted properly) run off those reserves for an entire endurance event.

Apparently, it’s all about teaching your body to metabolize your fat stores instead of relying solely on all those sugary gels we consume at the rate of 200-300 calories per hour.

In an interview with Men’s Journal, when asked what a typical day of food looks like, Zach responded, “For breakfast, instead of having cereal or oatmeal, I’ll have eggs and bacon with maybe some spinach. Lunch is usually a Cobb salad, and my favorite dinner is a tri-tip steak or something like that.”

What I like about Zach’s approach is that it’s not set in stone. It ebbs and flows based on his training, his lifestyle, season of the year, and also simply how he’s feeling on a day to day basis. He doesn’t demonize carbs, he just reserves them for when he feels his body really needs them.

If your body is adapted to burn fat really efficiently, you can imagine how amazing it might feel to finally release a gel bursting with carbohydrates into your body. Probably a nice bump in energy and performance!

Zach is quick to advise that transitioning to a high-fat diet should be done with care and proper planning. Graciously, he released a four part series on his blog to walk us through each step so that we can do it safety and be confident in the process.

For a deep dive, read Zach’s periodized nutrition protocol blog entries:

What supplements does Zach Bitter use?

Zach is sponsored by SFuels and uses their low-carb high-fat products before, during and after his training runs. While this list is a bit dated, Zach said he uses the following supplements in addition to his fueling protocol (

  • omega 3 fish oil
  • glucosamine chondroitin
  • lactic acid buffer
  • magnesium
  • vitamin k12/D3
  • whole food multi vitamin
  • CoQ10
  • spirulina powder
  • super greens powder

In a blog post about recovery nutrition, Bitter writes that, “I believe a healthy lifestyle allows you to get the nutrition you need from your diet, but with training volumes exceeding 25 hours a week at times, supplementation allows me to better meet the demands I put on my body—and help with recovery.” So before you head out to your local GNC, make sure you’re maximizing your vitamins and nutrients from your food itself!


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Zach Bitter’s Wife – Nicole

Nicole Bitter is an attorney and works as the Director of Compliance for Willis, Towers, Watson out of Phoenix, Arizona. She ran collegiately for Northwestern University in both Cross Country and Track & Field. She took that speed and transitioned it to the mountain/ultra/trail scene and continues to compete at the highest levels to this day.

A few of her accomplishments: (1) Nicole set the USATF 100 Mile National Record in 14:22 in 2015, (2) she won the Zane Grey ultra and still has the second fastest time ever on the 50 mile course (race established in 1990), (3) she won Rocky Raccoon 100 three years in a row (2013-2015), and finally, (4) she finished in the top-10 at the Western States 100 three times!

I’m going to place Zach and Nicole Bitter up there with Emelie Forsberg and Kilian Jornet as one of the sport’s true power couples. Sheesh, the talent pool is strong if they ever have kids!

How to Follow Zach Online

In the media:

If you want a deeper dive into the Zach Bitter mania, he catalogues all his podcast interviews, articles about him, articles he’s written, YouTube appearances, and more under the media tab of his website ( Dive in and kill a couple days. I’d definitely recommend the Joe Rogan interviews (he’s appeared on the show twice).


Zach hasn’t written a new blog post since 2017 but he still has a nice collection of posts to peruse dating back to September of 2011. He has a ton of irons in the fire so I don’t blame him that he gave up the blogging. Check out his legacy posts here (


Zach co-hosts the Human Performance Outliers Podcast with Dr. Shawn Baker ( They interview a variety of guests, looking at the outer edges of human performance, and have already recorded over 200 episodes!


Zach’s website is a great jumping off point for discovering everything he’s doing ( It’s fairly clean and organized with links to all his social media accounts, his blog, podcast, media, sponsors, coaching services and more!

YouTube channel:

Zach has uploaded 36 videos to his YouTube channel since he started two years ago. He has a nice combination of informational videos on topics pertinent to ultra running.

He posts videos that are associated with his big efforts including the the live streams from his recent treadmill world record, and he even recorded some weekly training updates and brings us into his kitchen for some cooking show and tell. Egg Frittata anyone?


With over 1,000 posts, Zach is pretty active on Instagram. He keeps his followers up to date with all his major projects and goals. He also posts lots of awesome desert running shots; who knew Phoenix was such a cool trail town? Check out his IG account here.


Turns out people still use Facebook. Zach posts all of his content on his Facebook page but doesn’t share a lot of personal tidbits or lifestyle photos there like he does on Instagram.


You can find Zach’s twitter profile here ( I always find it interesting to see what he retweets. He does do one of my pet-peeves though by tweeting his Instagram posts. Y’all know what I’m talking about. You post a photo on Instagram and then click the also-post tab to twitter. Ugh.


What watch does Zach wear? Coros Global Vertix.

What shoes does Zach wear? Always Altra, but he jumps between the Torin 4s, Timp 2s, Paradigm 4s, and Provision 4s.

How old is Zach? Zach was born on the 21st of January 1986 making him 34 years old this year (2020).

Where does Zach live? Phoenix, Arizona.

That’s a wrap on my Zach Bitter profile! He’s definitely one to keep an eye on. There’s no telling what he’ll do next now that he has a handful of world records under his belt; whatever he feels like I suppose. Trail, road, mountain, track, treadmill; the guy does it all! I hope you learned something you can integrate into your training and lifestyle. I know I have.


Up Next In Trail Running: 

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Why is My Running Pace Getting Slower? (top 10 reasons…)

Camille Herron’s 24 Hour Record | Training and Diet That Got Her There

Couch to 50k Training Plan (8, 12 and 20 Weeks Out)

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