🌵 Javelina Diaries 04: The Hotness

How I'm Training for 62 Miles in the Desert

My first 100k—the Javelina Jundred—is in 115 days. What have I gotten myself into? See daily runs on Strava and more journals here. Happy to have you along for the journey.

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I am a beginner again.

That a lifelong runner, ten-time marathoner, and guy who just had his best racing season ever can be so humbled is a testament to running’s resistance to mastery. We’re light one day, heavy the next. On the heels of euphoric breakthroughs, we experience confusing setbacks and wonder who changed the rules.

So it has gone between me and heat.

I’ve always loved summer running. Warmth radiates from cracked concrete and thaws the stiff limbs of long Montana winters. I dance through ridgetop wildflower fields and breathe deep the dusty air. The sun sees me and winks. I smile back. But not this year. 2025 has been different.

A Realization

During daily jogs this spring, when temps climb into the eighties and beyond, my heart rate shoots two zones above normal and is difficult to normalize. On long breaks in the shade, I’ve had a lot of time to think… mostly about whether running 100k in the desert is wise for someone who’s having a hard time acclimating to heat.

It has been frustrating feeling like I’m moving backward. But, on a recent shade break, I made peace with my new reality and said out loud: “It’s like I’m a beginner again.” I let the words float up and settle softly back down around me. With that, I committed to a training block of curiosity, kindness, and patience.

The Approach: Get Hot a Lot

That realization—I’m new here—laid the groundwork for embracing growth. A Zen beginner’s mind is open and free of preconceptions. It asks, What is this situation trying to teach me? That’s the mind I need. The season I’m in is not about recovering what was. It’s about learning to thrive in the circumstances of now.

Physiologically, with nearly two decades of accumulated fitness in the bank, I’m not starting over. I just need to experiment with some “process tweaks” to see if the heat tolerance needle can be moved. Enter active and passive heat training:

• Active: Many people (the science isn’t conclusive enough to say all) can improve tolerance and even increase blood volume by training hotter than “normal.” This could mean wearing extra layers or, as I’ve been doing, donning a non-breathable hot suit for 15-20 minutes on the treadmill. I have been incorporating active heat sessions once or twice a week since April, always on the tail end of a regular run so that my core temp is already high.

• Passive: Passive heat exposure (hot tub, sauna, and even hot baths) brings similar adaptations as active, just not as quickly. Two or three times a week, I spend time in a cheap sauna tent that, frankly, doesn’t get very hot (90-110 degrees). I do this after runs, listening to podcasts and relaxing. If nothing else, it makes for a nice mental break. I may also be the first person to intentionally self-bake in a hot vehicle. On several occasions, I’ve done 15-20 minutes of Truck Sauna™ after a workout. If you want to try it, I recommend a towel for your seat 💦

On another recent shade break, I had an epiphany. Run-stop-run-stop doesn’t simulate my desired race day rhythm. If I want to run more effectively in the heat, I should train continual movement. So, I have been focusing more on uninterrupted motion, walking instead of stopping when my heart rate creeps too high—hey, just like the Galloway run-walk-run method popular with new runners!

Of course, heat training is just one layer atop the broader rhythms of my summer running—races, travel, recovery, and all the juggling that comes with trying to sustain a strong season while staying open to change.

Training Notes

I’m knee-deep in a summer of trail running, punctuated by races roughly every month. The schedule means I’ve not been able to hold consistently high volume, because I’m always on a compressed build-taper-race timeline. But I’m learning a lot about what my body can handle running-wise, alongside normal life stresses.

I think I’m getting fit, but it’s hard to tell. Trail running doesn’t give you the clear benchmarks of the roads. Paces and heart rate are near-meaningless, and the 28k I ran in Montana in early May was wildly different than the 32k I raced in Idaho a month later. With progression being hard to track, the trails force a return to essence and feel. Coming off a year of road racing, that has been a little disorienting.

April

In preparation for Don’t Fence Me In, I increased vert significantly in April, racking up nearly twice as much climbing as the month before. With no races on the calendar, I was able to hit consistently high (for me) volume.

Coming off my birthday week at the end of March, I ran 15 days without rest in the first two weeks of April, my longest streak ever. Then, after one rest day, I did another nine days straight. While these bouts helped me hit (arbitrary) mileage goals, I can’t help wondering if the lack of recovery came back to haunt me on race day.

April Highlights (4 weeks tracked)

• Miles: 235 (March: 200)

• Vert: 26,650’ (March: 14,975’)

• Average HR: 125 (March: 125)

Notable Workouts

• 4/1: 20x1min

  • 10 road miles with 4x (5x1min on, 1min off)

• 4/19: Big Vert Energy

  • 14 trail miles with 3,200’ vert and 15x20s strides

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May

The month of May was all about Don’t Fence Me In (DFMI). The anticipation for, experience of, and recovery from this 28k in my Montana hometown was protracted and at times difficult. It’s not the most fun to write about still, weeks later. You can read my feelings in the immediate aftermath here.

Stuck in the doldrums and convinced I’d lost all semblance of mojo, I didn’t get back on the horse until two weeks after DFMI. That final week of the month was capped by a fun road excursion to Denver for Outside Festival, and I’m proud of myself for getting a run in most days of the trip.

May Highlights (5 weeks tracked)

• Miles: 165

• Vert: 13,275’

• Average HR: 123

Notable Workouts

• 5/24: 15x1min

  • 15 trail miles with 3,300’ of gain and 15x1min on, 1min off

• 5/26: Tired(ish) Tempo(ish)

  • 4x400 at 6:00, 2x800 at 6:20, alternate 7:00/8:00 for six miles

June

Volume stayed relatively low last month, owing to a 30k race in week two. I like to take a little taper the week before and week of a race, plus a lower mileage week after for recovery. That doesn’t leave a lot of month!

My race was the classic River of No Return (RONR) Endurance Runs 32k in Challis, Idaho. This event was everything that’s right about trail running: a challenging, scenic course, low-key vibe, and a passionate, dedicated community with reverence for the stories held in their mountains.

From the pre-race meeting to the barbecue afterward, RONR made me feel part of something unique. The course was rugged, rocky, and tough on the legs. I wilted in 80-degree heat in the final miles, but managed to hang on for an age group award and the feeling that maybe this body has some good running years left.

June Highlights (4 weeks tracked)

• Miles: 147

• Vert: 18,400’

• Average HR: 127

Notable Workouts

• 6/7: MacDonald Pass

  • 12 miles with downhill focus

  • 1mi down, 1mi up (warmup)

  • 2mi down, 2mi up (2x3min hard on the down)

  • 3mi down, 3mi up (3x3min hard on the down)

• 6/28: FTB Simulator

  • 19 miles with a lot of vert early on, followed by some ridge running and then a long downhill. This is roughly the progression of my next race on 7/13, the Foys to Blacktail (FTB) Trail Marathon

With three months of shifting terrain behind me—literal and emotional—I’ve begun to notice the real adaptation taking place. Not just to heat, but to discomfort itself. The deeper work isn’t just about getting stronger or faster. It’s about learning to stay with the moment, quiet the inner commentary, and let the experience be enough.

The Finish Line

There are three layers to any given moment: 1) What is actually happening, 2) Our awareness of the experience, and 3) The story we tell ourselves about the whole thing.

For some time, I’ve struggled to stay grounded in #1 (I am running and it’s 80 degrees). I move quickly through #2 (I feel hot and this seems harder than on cool days) and get mired in #3 (I run poorly in the heat and won’t ever improve).

This training block, I’m focused on centering around experience. Quieting the chatter is never easy, especially for those of us accustomed to answering the call of the monkey mind to strive and achieve. But it’s here, in the ever-changing moment that we find joy and ease in movement, and gratitude for what we’re capable of.

Run lightly,
-mike

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