Jason Steed Certified Primal Health Coach
Fat Fueled—Running On a Full Tank
In 2012 I competed in Ragnar's first-ever trail running event. It was called The Trail Experiment, held at Ponderosa Ranch, Zion National Park. This year I performed my own "experiment" namely to see how I would compete after several months of slower cardio training, and on a fat-adapted diet.
Known as the Maffetone Method or Primal Cardio, you essentially reduce your cardio workouts to fat-burning zone heart rate. For me that's 133bpm or lower. In essence, the lower heart rate zone helps you to train your body to burn nearly boundless fat stores for energy, thereby relying less on limited glucose stores for energy. There are other reported benefits such as staying away from a prolonged fight-or-flight hormonal responses indicative of chronic cardio efforts and accelerated aging at a cellular level. Bottom line, if you're driven by that "workout high" like I am then you're in for a whole new workout mindset with slower, shorter cardio sessions.
My own experiment in 2018 was to race faster by training slower
Back in September I picked up a copy of the Primal Endurance audiobook by Mark Sisson, narrated by his partner in crime, Brad Kearns. I was already well on my way with a whole foods lifestyle, having taken the Whole30.com plunge earlier in the year. Primal Endurance introduced me to a schedule for seasonal cardio, strength training and recovery. My first race this year would've been a month later, but I saw an opening for a spot on a Zion Trails Ragnar team and snatched it up. So, this would officially be my first race on a fat-adapted, low speed cardio mode. Oh, and regarding competing while fasting? Well, read on.
Gluconeogenesis Pulled the Weight
Molly, the organizer picked me up a day ahead of Zion Ragnar and we picked up some of the regulars: Bacon & eggs, bagels, brats, Swedish Fish, chips, bridge mix, and some fresh fruits and veggies. As part of my fueling experiment, I had packed my own foods, including cottage cheese, sardines, 99% dark chocolate, Mystic Mango Kombucha, organic walnuts (yes, I said 'sardines' earlier), olives, and a few organic mango strips (I inadvertently left my bag of avocados on the garage floor).
So, here's where it gets interesting. My first of 3 race legs was a 7.4-miler in the heat of day, and I ran roughly a personal-best 12-min. mile pace on a mix of steep terrain and soft sand. In this event my heart rate averaged around 170bpm (close to 95% Vo2 max), but I finished the leg feeling energetic. Three hours later I ate my dinner comprised of minimal carbs (apple, raisins, kombucha), medium proteins (brats, sardines), and an abundance of healthy fats (olives, hard boiled eggs, walnuts, almond butter). I was finished with dinner by 7pm, and my next race was at 11:45 pm. At the end of that midnight leg I felt great, and my heart rate averaged around 165bpm (another personal-best 12-min. mile pace). I stayed hydrated overnight with water only, and remained in a fasted state all the way up through my final 9:45 am leg (165pbm, personal-best 11-min. mile pace), then 2 hours beyond that.
In short, I was able maintain my energy by pulling energy reserves from fat cells, which are in much more abundance and burn more slowly than when burning glucose as fuel. The ability to access fat energy requires gluconeogenisis, a cellular process of stimulating and maintaining a body's homeostasis. But the body will always access the easiest and typically most prevalent energy source, glucose. Getting gluconeogenesis to instead access mostly fat-stored energy requires you're both fat adapted and conditioned to intermittent fasting.
Without fat adaptation, the body will always access the easiest and typically most prevalent energy source, glucose.
Intermittent Fasting
I've been experimenting with intermittent fasting for around 2 months, fasting between an 8pm dinner and 11am or 12pm lunch. I fast maybe 3 or 4 days per week, and sometimes on cardio training days. I hadn't initially planned to fast during an event like Ragnar, but the timing of my events along with my body's familiarity with fasting, got me thinking about it during the event. I broke my 15-hour water fast with a Macademia Pecan fat fuel packet from DropAnFBomb.com and delved into my lunch an hour later.
Post-race Assessment
I learned some valuable things from this experiment, having come away from the experience free from any gut issues, sore muscles, or noticable fatigue. First of all, for me, fueling with minimal carbs and maximized healthy fats gives me day-to-day energy that I've not had during my entire active lifestyle. And I see runners in my Facebook circle of friends who are constantly dealing with injuries, energy challenges, and in-event bonking. I know we are all built a bit differently, but seeing how in prior years I started confronting unexplained weight gain, IT Band right knee discomfort, and other incidental fatigue, I know for certain I'd be in a worse place right now without some of these training and nutrition tools. Learn more about the correlation between endurance and speed from this more eloquently stated scientific explanation from Dr. Mirkin.