David Roche is a beacon for hard work, self-belief, and pushing the boundaries of performance. From his debut 100mi course record surprise at Leadville to crushing that time a year later, here is how David transformed as an athlete.
Intro: This is Matt. I’m thrilled that David Roche is writing today’s piece. David is one of the people I learn the most from when it comes to fueling and performance and now you can hear from him directly. This blog is about how High Carb Fueling transformed him as an athlete, be sure to check out his favorite products at the bottom, over to you David...
Have you ever had objective data that you suck?
I have. And it came in the form of a “fatigue resistance test” meant to predict my ultra potential.
Fatigue resistance (often called “durability” in the exercise physiology literature) describes how peak performance deteriorates when fatigued after a certain amount of work. Megan and I developed a test early on in coaching to quantify fatigue resistance, with the goal of informing training interventions for ultrarunners.
The simple design: 90 to 120 minutes of moderate running in high Zone 2 and low Zone 3, followed by a 10-minute hard effort. Compare that to the same 10-minute effort when fresh, and voilà! The percentage always seemed like ultra destiny.
The champions we coached scored off the charts. I’ll never forget seeing Drew Holmen’s numbers way back in 2017 and nearly crapping my pants with joy, knowing he was going to change the whole game. Meanwhile, my scores were bad. Pathetic. Sad, but also funny. I wasn’t going to change the game. I’d be lucky to make it up the stairs without needing an aid station.
Then, the entire endurance world got turned upside down. If you listened closely to the east winds, you heard whispers of athletes in the cycling peloton of Europe consuming levels of carbohydrates that would sustain an elephant. A series of studies found reduced muscle damage, increased performance, and improved adaptation at 120 grams of cabs per hour. In coaching, I saw some similar fatigue resistance cellar dwellers have international breakthroughs, holding finishing tapes alongside dozens of empty gel wrappers.
I had nothing to lose, so I hopped aboard the super-high-carb train, pushing the numbers higher than any ultrarunner I knew about to that point. Overnight, my entire world got turned upside down.
Suddenly, I felt like I didn’t get tired during long efforts. I adapted to training like I was 10 years younger. My biomarkers got healthier (including my Hemoglobin A1C and blood glucose). I saved 15% on my car insurance. Et cetera!
In my first 100 miler, I set a course record at Leadville in 2024. At 36 years old, I learned that my baseline of crappy fatigue resistance wasn’t destiny. From the outside, it must have seemed like a golden retriever getting a master’s degree. From the inside, I knew the truth: carbs make impossible dreams seem inevitable.
My 8 rules for high carb:
During purely easy training days (defined as days in Z1/Z2) under 1 hour, there is no need to take mid-exercise carbs.
On purely easy training days between 1 and 2 hours, 45-60 grams of carbs per hour is plenty.
On purely easy training days above 2 hours, 60-75 grams of carbs per hour is ideal.
On easy/moderate long runs where the effort is not purely easy (like in an ultra), try to fuel at 75-90 grams of carbs per hour no matter what the duration.
On moderate/hard training days (with Z3+ work) under 90 minutes, 60 grams of carbs per hour is ideal.
On moderate/hard training days above 90 minutes, aim for 75-90 grams of carbs per hour.
Once an athlete is experienced and finds benefit from 75-90 grams per hour, they can experiment with 105-120+ grams of carbs moderate/hard training days above 90 minutes and easy/moderate training days above 2 hours.
In races, apply the lessons learned in Guidelines Six and Seven to determine carb intake, trying to max out totals (while doing GI training, which is a topic for another email).
When I reset the Leadville record in 2025, I got to 150 grams of carbs per hour for the first 10 hours. The golden retriever got a PhD. It’s a classic Air Bud situation!
We are so lucky to have advanced products that make this type of fueling possible.
My favorite high-carb products:
Science in Sport Beta Fuel gels (the one gel to rule them all)
Enervit gels (Michelin star taste)
Precision gels (the caffeine gel could power a space shuttle)
Thank you to Matt and The Feed for letting me scream my message from the rooftops: you have no idea what you are capable of until you go all-in on high carb for a few training cycles.
- David
Photo Credit: Cody Bare
