Hiker on top of mountain running on a trail

Feeling Refreshed After Every Workout

Zone 2 training reviewed through many real life examples.

Having learned about the transformative effect of Zone 2 training and its underlying mechanisms, it is natural to want to more fully explore the protocols and how they might fit into your training program and lifestyle.


Until your metabolic fitness catches up to your muscular capacity, you will be dialing back your pace. For the initial ten weeks, you will need to suspend your typical evaluation of a workout’s effectiveness. Understanding that this will work for you is the vital bridge to get you through these first several months.

Two goats talking while training outdoors. One says "I'm sorry to say that your fitness assessment puts you in the "easy prey" category, but we can work together to fix this...

A frequent Zone 2 training question is how the focus on fat oxidation interacts with nutrition and body composition. While we still want carbs for fuel, the evidence suggests that we can train extensively without supplemental calories while in Zone 2. Alex Hutchinson describes in Endure: Mind, Body, and the Curiously Elastic Limits of Human Performance how prominent climber Adrian Ballinger “shifted his training following a failed attempt to summit Everest without supplemental oxygen”:

Lab testing showed that Ballinger’s metabolism shifted from burning predominantly fat to predominantly carbohydrate at a relatively low heart rate of 115 beats per minute. In the “death zone” near the summit of Everest, where appetite is suppressed and digestion and other bodily functions begin to shut down, this carbohydrate dependence left him starved of energy, shivering uncontrollably, with hands so numb that he could no longer work the carabiners that protected him. Wisely, he turned back two hours from the summit.

To help Ballinger tap into his fat stores more effectively, Johnston told him to add fasted endurance workouts to his training and shift to a higher-fat diet. The changes were initially challenging: Ballinger’s usual twelve mile runs turned into seven miles slogs taking the same amount of time. But before long, he was going out for five-hour workouts without needing to eat anything. A return visit to the lab four months later confirmed that his fat-carbohydrate crossover point had moved from 115 to 141 beats per minute, allowing him to rely more on fat during moderate-intensity ascents and preserve his precious carbohydrate stores for when they were really needed.

In the spring of 2017, Ballinger and his climbing partner Cory Richards returned to Everest, with Johnston and House monitoring their uploaded heart rate data from afar. On the 12-mile climb to Advance Base Camp, higher than the highest point in North America, Ballinger’s heart rate was below 120; two days later, climbing to the North Col, it stayed below 125. The difference from the previous year was dramatic, and on May 27, Ballinger joined the very short list…of those who have stood on the roof of the world powered by their lungs alone.


Getting the idea? Here are some additional brief case histories of Zone 2 progressions:
Todd Marentette, a 46-year-old runner from Ontario, Canada, had been training at an 8:00 per mile pace. Running at his MAF calculated zone slowed his pace to 12:00. He focused on his form rather than thinking about his pace. After a year, his pace was back to 9:40 at the lower heart rate, and he had noticeably improved his energy and lost significant weight. His marathon time dropped from 5:00 to 3:47.
Danny Huibregtse, a constantly jet-lagged pilot from the Netherlands, bonked out while improving his 3:59 marathon to 3:38. After adopting Zone 2 training, he dropped his time to 2:34. He also embraced Chi-running, which brings Tai-Chi and posture principles into the running form.

Why So Many Examples?

There is something to learn from the dynamics revealed in each Zone 2 example throughout this essay. Stack them together and the picture starts to form.

Alex Karp, the Palantir CEO of Palantir, featured in this Fortune article: “…Skis 5 hours a day and ‘runs like a deer’. Now he has the same body fat percentage as peak Michael Phelps.”

⁃ He advised those looking to emulate his routine to go the “slowest pace a human can run for as many hours as you can afford. And then once, preferably twice, a week, you’re doing [speed] intervals. You’re almost always moving like a snail—except for when you’re doing intervals and you’re going fast.

⁃ Training in longer stints with short bursts has since become a “discipline” worth sticking to: “I saw results after 18 months—and especially huge results after 36 months.”


Kilian Jornet, perhaps the greatest trail runner of all time, logged 1200 training hours over the year—spending 77% of his time in Zones 1 and 2:

Kilian has consistently averaged 1000+ hours of training per year, mostly easy, across multiple sports. His aerobic roots run deep. For all of us, the first principle of endurance training is to stack up easy volume over time. The foundation for all performance from the 800 meters up to 200+ milers is how the aerobic system processes energy and associated fatigue. That ability comes from the daily grind of easy training.


Rich Roll, in Finding Ultra: Rejecting Middle Age, Becoming One of the World’s Fittest Men, and Discovering Myself:

“But if all I do is go slow, how will I ever get fast?” I asked Chris.

“The prize never goes to the fastest guy,” Chris replied. “It goes to the guy who slows down the least.” True in endurance sports. And possibly even truer in life.

…Up to this point, I’d been spending the vast majority of my running, cycling, and swimming sessions in what is referred to as the “gray zone”—a dreaded no-man’s-land where the effort exerted exceeds that which is required to properly develop the aerobic engine, yet falls short of the intensity necessary to significantly improve speed or increase anaerobic threshold. It’s that level of effort that leaves you feeling nice and winded after a brisk run but yields little in terms of performance improvement. In actuality, such training undermines true progress. It leaves you tired, with little to no gains in either endurance or speed. It creates plateaus that stunt athletic development, and often leads to injury. And it is by far the most common mistake made by amateur endurance athletes—myself included.

Allocating Our Energy

Most of us have several priorities ahead of athletics. We give our best energy to our closest relationships, balanced closely by our commitment to work and important projects. When it comes to slotting in fitness, we do our best.

Constrained by time, we often go-for-it when we do workout. Consequently, many recreational athletes are just piling on the same stressors that lead professionals to burnout.

April Zilg describes chasing a gold medal at the Paddleboarding World Championships:

I trained.

I trained so F@CKING HARD!!!

I'll never forget my last session from Goleta Pier in California. I went out a few days before my flight and did 2.5 hours of 20min pieces as hard as I could…
…I was cooked. I raced. But it was pathetic. About half way through the course, I could barely breathe, I felt like I could die. My heart rate was dangerously high, not to mention the mental anguish of training for years and getting to the world championships just to absolutely f@cking blow it. I hated myself. I hated the experience. I got so sick I couldn't talk.

Once home, I coughed and sneezed with dis-ease for about 3 weeks. I should note that even before arriving in China, I had packed on close to 20lb of extra weight - and it wasn't muscle. It was that hormonal imbalance weight around your midsection, the kind you get if you under eat and your body is panic-storing energy for your insane training and racing habits.  

I never wanted to paddle again.


What would training look like if it wasn’t one more source of challenging stress? What if we acknowledged that we already live at our limits of adrenal stimulation and high cortisol?

Turning On and Tuning In


Zone 2 training has been described as training slow to race fast, but I think a better description, albeit not as catchy, is turning on the slow twitch muscles while tuning in awareness and form.


The Chi-runner’s focus on postural form resonated with me, and not just because my initial Zone 2 running efforts resembled those slow moving Tai-Chi practitioners in the park. It was because when I slowed down, I began to notice things like my core and shoulders and neck placement, how my legs came up and where my feet struck the ground. I found myself practicing awareness.

A dog watching video of himself running with his tongue hanging out and says "Oh my god, do I really look like that when I'm running?"


Kilian Jornet combines his aerobic training with such mastery:

He likes slower days “on terrain that challenges other aspects (cognitive, mental, technique, visualization…and they’re much more fun!).”

…on purely easy days, you can have fun with it! Plus, working on technical abilities requires constant reinforcement, like all cognitively and neuromuscularly demanding physical movements.

When we are no longer focused primarily on exertion, it gives all of our senses a chance to be involved.

The Next Great Aerobic Training Narrative

In the first essay of this series, we shared how Mark Allen dropped his MAF (Maximum Aerobic Fitness) running pace from an 8:15 mile to a 5:20 mile—an effort level that had previously left his heart redlined at over 190 bpm.


Those times are so stunning that it is easy to forget that his improvements were forged via restrained Zone 2 exertions. Rich Roll in Finding Ultra:

True to Chris’s word, unwavering adherence to the plan began to pay significant dividends. I found myself able to run quicker without my heart rate escalating. What started at a 10:15-minute-per-mile run pace at 145 beats per minute was soon a 9:30 pace. Before long, an 8:30 pace morphed to 8:00—all within the sacrosanct Z2 range.

But the bulk of my training was spent on the bike. Because the body can ride many more hours than it can run or swim, it’s the optimal and most time-efficient way to build endurance fitness without risking leg and shoulder injuries. And by sticking to the ethos of Z2, I was surprised to never experience the debilitating fatigue I’d grown accustomed to as a collegiate swimmer.

Escalating volume very incrementally gave my body time to adapt without suffering exhaustion, the idea being that aerobic zone training allows the body to train day in and day out without heading into that black hole of fatigue that can bury an athlete for weeks, sometimes months, and destroy a season.


These are all great case histories. However, I’m now most interested in discovering new narratives. If you’re like me, you might find yourself asking how a regular person might lock into some of these transformations.

I’ve shared a lot of Zone 2 training links in the Digital Garden section of Always Invert. However, I am also interested in setting up a private group where we can dig into this a little deeper and share a bit more freely. Let me know if you want to join in. Zero cost of course. Just friendly sharing.


When I began my Zone 2 training, I believed that the biggest risk was that boredom. But soon enough, I was taking it all in. Embracing awareness not only improved my form but added new levels of appreciation while out and about in the world.


What about establishing a deep love of training? Who knows? That might happen. Which would be amazing and helpful as the adaptations we are seeking will take years to develop.


One last observation. I used to decide at the end of a workday if I had enough energy to “bring it” for a workout, and if so, did I have enough time available to slot it in around family and dinner and still being able to wind down in the evening, aka, Zone 0 training.

Nowadays, without the need to “go for it”, you might just find Zone 2 is a better wind down to your day. This can also be combined with the opportunity to catch up on all those streaming shows guilt-free, and your posture will undoubtedly improve compared to sitting on a couch.


Recognizing that you feel refreshed after every workout will significantly reduce your resistance to getting started.


Until next time, take it slow!

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