"Ever think of giving it a try?"

It was a year since my knee surgery. Liam needed new running shoes, so we were back at our local shop, the same place where I decompensated after that morning at the symphony. My youngest son was now a senior captain on the JSerra cross country team, tall, independent, and fully versed in the ritual of purchasing trainers and flats.

As Liam bounded off for a test jog, the salesman turned my way. He was new. Part of the myth about being a runner is that we all look alike. You hear people say it all the time: "He looks like a runner." It's code for lean, and sometimes a little too thin. But in truth, there's no singular shape for runners. The growth of running from a niche sport into the world's most popular form of exercise changed all that. Spectate for a morning at any 5k or half marathon and you'll see competitors of all girths and gaits. Each wears a race number and puts one foot in front of the other. Thus each and every one is a runner. Actually, they don't really need the race number — putting one foot in front of the other is proof enough.

Or, as I like to remind myself on those days when the pace lags and my legs feel like bricks, none of those people looking at me from their cars care about fast or slow. All they see is a runner.

I should not have been surprised when the running store guy tried to double his sale. Yet I was devastated he didn't assume I was a runner. My identity has been tied up in running for as long as I can remember. The knee injury came out of nowhere, a sudden inflammation of the joint that occurred while training for Boston. I do not know precisely how I got hurt, because it basically went from a perfect knee to a swollen and incredibly painful gathering of ligaments, tendons and cartilage. But a little online research showed me it was preventative: I sit too long during my writing day, don't stretch before running, increase my mileage before a marathon too quickly, don't drink enough water, and like most runners, was surprised to find that I have very weak hip muscles.

One fact was certain: cartilage in the knee joint is supposed to slide against itself five times smoother than ice on ice. Decade after decade of taking my body for granted had my right knee grating like a bag of rocks.

The surgeon was a triathlete. There was every hope he would give me the green light to run as soon as the procedure was complete. Instead, in the spirit of preventative medicine, he suggested I train the same way he did — swimming, biking, and very little running.

But I didn't want to be a triathlete. I didn't want to be callous in my personal relationships, anal-retentive about my training logs, shave my legs, sport an m-dot tattoo, and endlessly obsess about the correlation between caloric intake and bowel movement consistency.

I just wanted to be a runner..

My body feels different —I would even say better — for having run. Even on days when life is complete shit, there is a moment when the mind, body, trail, and sensation of getting stupendously lost in the act of running leads to a palpable feeling that all is right with the world. I'm not talking about the runner's high — I'm saying that I feel closer to God.

Or, as my friend Terry Sedgewick, major domo of the House of Pain, states simply: "Running has a different sweat."

I was on crutches for five weeks after the surgery. I had no choice but to swim and bike. The knee felt wobbly for six months after that. It might have been in my head, but there was no way I could run on it without risking more injury.

I stuck with the mountain bike and pool. To mix things up, I sometimes ran in a flotation belt, legs churning as if I was in full stride, head barely above the waterline, eyes focused on the sycamore trees surrounding our community pool, pretending I was somewhere on a trail.

But I wasn't. I was in the special lane roped off for lap swimmers, with sunbathers on the deck and children splashing in the water just the other side of the buoys. My presence was annoying to the lap swimmers, who had to swim around me during their relentless back and forth above the black line. I was completely aware that I was an awkward sight — an obstruction, a nuisance, a man clearly out of place — but at least I was accomplishing something that made me feel, if ever so slightly, like a runner.

Eventually, I'd pull my self up onto the deck. Sometimes I'd jog a barefoot lap on the grass at park next door, ignoring the soccer nets that had no business cluttering the green expanse in the middle of baseball season. Every step hurt. I didn't yet know the importance of words like "mobility" and the need to strengthen my hips to take undue pressure off the knee. All I knew was that my leg still didn't feel right. Months passed. The pool running, mountain biking and jogging on the grass became infrequent.

Then one day, I woke up and realized I was no longer a runner.

Not by any stretch of the imagination. The part of me that ran the hills as if they were my own property was no more. The body at rest stays at rest. The body in motion stays in motion. I had been at rest too long. My legs had forgotten how to do more than hobble. Running was for people from another planet. More than anything else, I was afraid of making my knee worse, and perhaps having another surgery.

So it was that the third time I got fat was after knee surgery.

It's what happens when life and fear get in the way of being the best version of myself. It's also the slow progression from medium to large, skipping completely over husky en route to XL. Inevitably, the physical side effects of gaining weight such as high blood pressure, decreased flexibility, and just a wee bit less manliness when I needed it most, made themselves known. It had been fifteen years since that initial visit to the House of Pain. But if anything, I had let myself fall into worse shape than when I first set foot inside those doors.

I missed the things runners say without knowing it. "That would be a pretty running trail," my wife remarked one day on a train. We were in Norway, along the fjords. A narrow goat path cut through a thick green pasture, weaving along the contour of a long body of water covered in mist. I knew just what she meant.

I longed for the things runners can do that normal people are never, ever allowed to do in public. For instance, a man or woman in a business suit cannot discreetly answer the call to nature by jumping behind a tree. Runners can. Most do.

Runners spit and blow snot rockets and fart mid-stride while running up a hill surrounded by their best friends. They talk about their sex lives and politics and thoughts on religion; their children, their fantasies, and failures; their finances, self-image, and the ten things in life they fear most. There are no boundaries.

A male runner can go bare-chested on a city street any time of year, no questions asked. A female runner can do the same in a jog bra. Not so for the normal populace.

Runners write grocery lists, arguments, briefs, poems; calculate split times, family budgets, travel expenses, and the precise number of days to taper before the next big race — all in their heads, without speaking or even moving their lips, as the miles pass. Some ideas disappear like smoke before the run is over. The good stuff percolates in the subconscious, seemingly lost forever before presenting itself once again as a problem solved.

A runner has a love-hate relationship with race day nerves. I call it "waking up nervous." Races are a reckoning. Trying to be a better version of you. This is physically, mentally, and emotionally painful. Who wouldn't be nervous?

In our household, it was now my wife who was waking up nervous. Callie had become the runner in our family. The woman who didn't know a trail ten years ago was suddenly running half-marathons and putting together her own small running group.

Ironically, I was more fixated on running than ever before, thanks to my ongoing role as a high school distance coach. It's been my avocation for almost two decades. I spend hours each week not just planning workouts and studying methodologies of the great coaches like Vigil and Daniels, but also reading new literature about subjects such as the active role of the central nervous system in our training. Not a day goes by that I don't plan, strategize, and strive to learn more about the science and art of distance running. Afternoons coaching my runners and forming friendships within the coaching community are some of the greatest blessings I have ever known.

I don't know whether to call it the butterfly effect or a snowball rolling downhill, but the universe eventually made itself known. Somewhat randomly, a few friends celebrated my birthday on social media by posting old photographs. I was running in almost all of them. I wanted to be that guy again. So I ran a little. A jog on the Live Oak Trail where no one could see me. A walk-run through Hyde Park where there were so many people witnessing my efforts that I was actually anonymous. Everything hurt. It was horrible. I couldn't believe that a sport that had once been so carefree, and which had physically sustained me for so many years, felt so damned hard.

So I stopped.

Which only made things worse. One September morning, as my team was wrapping up the first workout of the day, I walked into the neighborhood 7-11 to buy them post-workout chocolate milk. I get the kind with added protein. It's the perfect recovery drink.

The owner is an old friend who has done well for himself — well enough that he hadn't worked a day in the store for years. I waved when I walked in. He gave me a curious smile.

I gathered up the chocolate milk from the refrigerated section. There were sixteen in all. I hugged them in my arms to hold them as I stepped to the counter. A line started forming behind me.

"I almost didn't recognize you, Coach," my friend growled loudly. He's a big man whose voice is booming in normal conversation. Now it seemed to roar from the hot dog grill by the cash register all the way back to the beer case, falling on every ear in between. "You're so big. I've never seen you that large. Wow. You're really huge. You used to be so skinny. Have you been lifting?"

In a moment like that, all you think of is the draft pints of craft beer, that heated blueberry muffin at Starbucks, the many-many-many hamburgers and spicy hot wings that comprised dinner on the drive home from practice, the pizzas that didn't stop with just two slices, the instant fortification of fast food burritos with extra onions, and basically every calorie I'd stuffed into my face with the exception of salads.

And I realized I had a choice.

I could find a way to grow old with a healthy balance of diet and exercise, once again working hard to become the athlete and lover I wanted to see when I looked in the mirror, knowing I could be there for Calene in mind, body and spirit for decades to come.

Or I could choose not to.

"A man without self-discipline is like a city whose walls are falling down," I read in Proverbs not long after.

And the die was cast.

Time to be a runner — again.

How do you start all over?

My comeback began with humility, and by pretending I'd never run a step in my life. I followed all the lessons I preach to the kids I coach when they show up for their very first practice: buy good shoes, run and walk at first, run on dirt and grass whenever possible, and most of all, show up every day. Consistency is the key to success in all things.

I added new elements to my training, things like mobility, hip strengthening exercises, and a greater emphasis on daily core conditioning. For the millionth time in my life I reminded myself that being a runner does not mean I can eat and drink anything I want.

And I returned once more to the House of Pain. "Nice to see you, Coach," said Terry Sedgewick, looking no older than my first visit so long ago. "Let's get to work."

It's a simple sport, this endeavour of putting one foot in front of the other. Yet it's so damned hard.

That's what makes it great.

I'm not all the way back yet. But I'm out there every day. You don't know how much you miss a discipline until you embrace it again. It's an abused word, discipline. Yet nothing great happens without it.

It's easy to let up, ease back, lower expectations. But "Keep Pushing... Always," means just that. Always.

That's how to be a runner.