In today’s episode, we’re joined by Zach Bitter, an American ultra-marathoner. In May of 2020, Zach ran 100 miles on a treadmill in 12 hours, setting a world record. Today’s episode will dive into all things ultramarathons, running, endurable bodies and Zach’s diet and training regimen.

As a kid, Zach participated in various sports, eventually realizing his gift for running. In 2010 he jumped into a 50-miler and was hooked from then on. By the end of the next year, he was training specifically for ultramarathons, though he enjoys switching up his routine from time to time. Zach held two 100 mile records in running. The first being 11 hours 19 minutes in August 2019 and the second in May 2020, 100 miles on a treadmill in 12 hours and 9 minutes. Having to match the pace of the machine was the most difficult aspect of his treadmill ultramarathon.

Then, Zach discusses the mental demons that can arise over the course of an ultramarathon. In order to make it to the end, the pace of a 100-miler has to be much slower than your single mile or even marathon pace. Thus, the mentality differs greatly when running such long distances at a slower pace, allowing for the mind to wander much more. Nick offers his own experience realizing the importance of pacing and not pushing yourself to be as fast as you can be. His slower morning runs are his most creative part of the day .

Zach has learned to use the following week or two after an ultramarathon to reflect on the experience. Uniquely, because of the length of ultramarathons, it’s rare to actually train for the full distance. He likes to incorporate block training into his routine, focusing on specific quality sessions back to back. Depending on the type of race he has coming up, Zach says his training varies quite a lot in terms of intensity. About 8-10 weeks before a race is when he really begins to focus on things he will be doing during the race. He says the most difficult period of training is during the very beginning coming off from an off season. But, his body catches up to him and he quickly adapts to the regimen.

Zach tends to maintain a diet higher in fats and lower in carbohydrates. On average, his diet consists of 10% carbs, 20% protein and the rest fats. On days before he works out harder, he finds it beneficial to incorporate more carbohydrates into his diet. In preparations for lower intensity higher volume races, such as 100 milers, he sees the implications of carbohydrates or even a strict keto diet. During his college years, he began looking more into the scientific aspects of the foods he ate. Around 2011 he started getting more interested in a low carb diet when he noticed irregular sleeping and energy patterns. It took time to figure out what kind of foods worked best for him. He’s experimented with diets ranging from plant based low carb to animal based low carb and everything in between. Everyone’s gut and microbiome is different, so it’s important to find out what really works for you instead of basing your diet on someone else’s.

In Zach’s opinion, maintaining peak-season fitness isn’t sustainable year-round. During his off seasons when he isn’t training for a specific race, he listens to his body and doesn’t push himself. During a race he is typically at his leanest, so he doesn’t mind gaining a few pounds when off season rolls around. His training foundation remains mostly the same throughout the year, and is just tailored a bit differently towards any upcoming races. He averages about 100 miles per week factoring in both on and off seasons. He is cautious of over training, believing it to pull away from your potential down the road.


0:05 – Introduction of today’s episode and guest.

2:30 – Zach’s background in running.

7:57: – Zach discussing his mentality during the treadmill 100 miler.

13:55 – How Zach navigates training and race preparations.

27:10 – Most difficult period of training. 

30:30 – Overview of Zach’s typical diet.

37:40 – Zach’s relationship and experimentation with nutrition.

44:40 – What Zach’s off season looks like.

51:11- Zach’s weekly mileage average.

54:40 – Zach’s upcoming transcontinental event.


Learn more about Zach Bitter.

Follow Zach on Instagram.

Visit the Fight for the Forgotten website.

Learn more about BPN