It always comes as a surprise, the first time: On a late-spring afternoon, I’m running repeats of a half-mile trail segment that snakes over two hills alongside a field. As I approach the biggest hill, I prepare for the slog, expecting to wallow in the steep, sandy surface and to have to muscle my way over.

Instead, my feet dance over the uneven terrain, my legs power up the slope with ease. I crest the hill and charge down the other side, my strides extending behind me, my hips channeling their force smoothly into forward motion.

I feel light and balanced, a fine-tuned machine. I’m breathing hard and my heart pounds in my chest, but I’m in control. I fly over the ground, driving myself faster as I descend the hill and hit the final straight.

I can sense tumblers falling into place, unlocking the “thing behind everything” that makes all else seem second-rate, as John Updike described in Rabbit, Run. I’m riding the wave, hitting the sweet spot, in the zone, in flow. As I finish the workout, I feel invincible, fully alive, connected and powerful.

The next day, the feeling is there again as I accelerate to a cruising rhythm on an eight-miler. At this more relaxed pace, power plays second fiddle to a consciousness of deep strength, the “tireless state” that legendary New Zealand coach Arthur Lydiard spoke about. It lures me to extend my run two extra miles, then four. I roll along, barely touching the ground, feeling like I could run over the horizon.

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While the exact moments when I unlock this power always come unexpectedly, the elements that get me to this place are no secret. I don’t have to wait for random lightning to strike. In fact, with running, it never arrives out of the blue, as it might in other sports. You may randomly sink a jump shot or drive a golf ball on a straight, soaring flight, but you’ll never levitate on the run without first putting in some prerequisites.

Once you learn the way, however, running provides a predictable path to satisfaction. I can control running variables far easier than I can relationships, work, or community, and the payoff is never disappointing. Running is what I turn to when I’m tossed about and need to know that, at least in one area, I can act on my world and be confident it will respond and reveal that place where life resonates in harmonic frequencies.

Class predictable doesn’t mean it is easy, however. I’ve learned that I can’t get there until I put in consistent 35- to 40-mile weeks for more than a month, regular long runs of at least 80 minutes, and a small amount of speed stimulus. That speed includes some all-out strides a few times per week and quality workouts like yesterday’s 800s.

The method is straightforward: Build an endurance bed of hot embers, gently fan it with speed, being careful not to get greedy and blow too hard, and one day flames burst forth. I can never tell exactly when it will combust, but I know what conditions need to be present before it does.

What I need to get there is not necessarily what you’ll need. The elements are essentially the same, but every body responds differently to each stimulus: volume, intensity, frequency, variety. You must discover your own unique combination.

Not only is your recipe different than mine, but the recipes also change over time. As I’ve aged, I’ve found I need to add one more ingredient. While I can get fit on running alone, I won’t ever float unless I also work on flexibility and strength. Outside of my running, I mostly live the life of a sedentary middle-aged American, and it has taken a toll. To dance like Bekele I need to get my body back in balance, and correct for years of sitting and hunching.

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And while for me, running isn’t “exercise”—a chore, something I force myself to do because it is good for me—strength and flexibility training is. It’s hard to achieve flow while stretching my hip flexors, hard to even know if I’m making progress. There are no Strava apps to track how many squats and donkey kicks I did today, and no one is ever impressed with my toe splay ability or how long I can hold perfect one-leg bridges. My desire to keep running and to run well, however, has driven me to do them. But I still rarely schedule this exercise time. I’ve mostly made the supplemental work part of my daily life: I do air squats while I’m grinding coffee beans, short foot exercises at my desk, hip flexor stretches while reading email or on a call.

These new routines, while first only accomplished with discipline, have now become habits that yield benefits. I am taller, lighter, more balanced and fleet-footed than ever in my life. When I don’t do the exercises, I feel off, a bit gross, like I would if I skipped brushing my teeth. On the run, everything gets harder, and old aches and pains creep back. I have fewer, if any, moments of grace like I did on yesterday’s hills and today’s rhythm run.

About those back-to-back flights: After riding high two days in a row, I’m tired. Tomorrow I’ll be sluggish. The feeling of connected power is not a place you arrive at and stay; it is fragile and temporary. No worries. The bright flame may have burned itself out, but the embers are still there. This base of steady strength is a comfortable place, one that provides its own satisfaction if not the same heady rush.

I won’t tempt the gods and try to force the feeling to stay another day. I’ll run easy for a while and rebuild the fire before I again fan it into flames. I may need to experiment with the ingredients and the timing, but I know it will be there for me. I know, as well, that it will be worth finding. It always is.

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