(Photo: Warren Goldswain/Shutterstock)

When I first started running regularly, about 30 years ago, three miles qualified as a decent workout. That distance soon crept up to five miles. After training for my first marathon in 1992—26.2 miles—it was six or seven. When I joined an official marathon-training group about a decade ago, eight became the magic number. Today, as an avid marathoner and sometimes ultra-marathoner, I need to run closer to 10 miles a day to feel the satisfaction of a workout. It’s not unusual for me to have run 15 miles before the rest of my household has even gotten out of bed.

This might not sound like much of a problem. And in many ways it’s not. Aside from a pulled hamstring and a torn meniscus, running has generally kept me in good physical condition. Even in middle age, it’s hard to run 60 to 70 miles a week and become overweight. Research shows that avid runners tend to avoid depression, sleep relatively well, and experience reduced stress—all of which has generally been the case for me. Plus, because I routinely exercise with a large group, running has become, for me, as much a social as a physical activity, thus delivering the numerous benefits that an active social life has been shown to confer.

But still, there are times—usually when I’m thoroughly exhausted—that I find myself concerned about what increasingly looks like an addiction. The fact that I now need more and more miles to experience the benefits of physical exercise comes uncomfortably close to the chronic substance abuser who needs more and more hits to get high, or the alcoholic who needs more and more drinks to feel sedation. Perhaps we’re too quick to highlight addiction when an activity becomes intense, but still, the parallels are hard to ignore.

Would addicts be pushed to go cold turkey, as many drug and alcohol addicts are advised to do? That option would deny them the real benefits of a healthy activity they had merely taken too far.

Adding to my concern is the poor judgment that too often interrupts an already intense workout regime. Two weeks ago I woke up feeling a little under the weather, but this condition didn’t keep me from leaving the house at 4:45 a.m. in rainy, 38-degree weather to cover 11 miles with hill intervals worked in for good measure. It was really never a choice. I wouldn’t have considered doing anything else. When I finally made it back home I felt like death, immediately came down with a high fever, and was confined to bed for three days. This was, I had to admit it, a self-inflicted flu.

And I’m smarter than that.

THE PSYCHOLOGICAL LITERATURE ON exercise addiction can be confusing. Despite the inclusion of other behavioral addictions (such as gambling), exercise addiction is currently not listed in the Diagnostic and Statistical Manual of Mental Disorders. That exclusion, however, hasn’t prevented an upsurge of professional research on the subject, especially over the last 20 years, as endurance activities such as marathoning and triathlons have spiked in popularity.

What we now have is a lot of information about a problem that’s not officially a problem, but is still deemed by experts to be possibly “devastating” (PDF). Making matters more confounding is the fact that intense exercise is often prescribed to help mitigate the effects of certain mental conditions (such as depression), reiterating the paradox that an activity we should all be doing for our physical and mental health—regular exercise—can also ruin both.

Fortunately, there are a few things we do know with reasonable assurance about this otherwise elusive condition. An estimated three percent of the general population suffers from exercise dependency. The more endurance-oriented the sport—ultra-marathoning, Iron Man competitions—the better the chances there are for some sort of addiction to set in. Exercise addiction overlaps with other disorders—most notably eating disorders, but also drug and alcohol abuse—about 25 percent of the time.

We also know what this dependency is not. However it ends up being officially codified, exercise addiction (or what looks like it) has been clearly distinguished from obsessive-compulsive disorders (such as anxiety-related issues) and impulsive control disorders (such as gambling). Unlike these behaviors, excessive exercise is more like an addiction in that—like so many other addictions—it’s notable for a “dual capacity to reduce negative affective states while also creating positive affects, be it a rush or improved mood.” In other words: a double whammy, one that, fully experienced, is hard to resist.

The most useful research on exercise addiction charts a plausible course of declension from recreational exercise to dysfunction. In this sense, it offers something of a behavioral map for nervous runners to check in on from time to time. On the safe end of the spectrum, there’s recreational exercise. As one would expect, this is the kind of exercise that substantially improves our quality of life. One controls the exercise, can stop when it’s time to stop, enjoys basic health and fitness benefits from it, doesn’t freak out when it’s missed, and appreciates the modest changes in physical appearance—changes that enhance self-esteem and inspire dedication to staying fit and living the good life.

But from there it’s a slippery slope into darker territory. “At risk exercise” involves a more conscious awareness of exercise’s mood enhancing impact. There may be a neurochemical element kicking in for those whose workout schedule enters this phase, with endorphin production dropping off and the body making up for that decline by working harder to extract pleasure from more sustained physical exertion. My own experience of needing increasingly more miles to feed the seductive opiate rush of a workout speaks to the insidious impact of this possible chemical rationing. The body and mind recall all too vividly what it’s like to exist (blissfully, mind you) in post-exercise equilibrium and will do what it must do to rediscover that balance. When your workouts are overly tuned in to this “high,” you may have crossed a line.

The next phase approaches the doorstep of addiction. It’s what Marilyn Freimuth et al, who have cogently laid out this typology, call “problematic exercise.” Leading researchers on the topic tellingly explore this phase using the psychological criteria for substance dependence. Much like a problem drinker who keeps drinking despite having had enough alcohol to alleviate stress, the problematic exerciser will pile on the miles despite having already met the articulated goal.

I see this behavior all the time among my fellow runners. If the training schedule says to do 18 miles, with 10 miles at marathon goal pace (MGP), runners will do 20 to 22 miles, with 12 of those miles well ahead of MGP. They will do this—I will do this—despite the counterproductive fatigue and increased risk of injury that inevitably results. Then they’ll spend the day kind of proud of the added effort. Throw in the physical benefits that accrue from kicking your own ass during a hard workout, and this failure to stick to a rational plan becomes easier to understand. Elite runners tend to like how they look.

The final stage is all out addiction. According to Friemuth et al, this is the point at which “the frequency and intensity of exercise continues until this behavior becomes life’s main organizing principle.” Existence centers on exercise. I’ve seen a lot of this. I’ve known runners who, stuck in a hotel with no treadmill or safe place to run, will, in a mild panic, jog around the parking lot for 90 minutes. I recently interviewed an elite triathlete in her fifties who, when she had to miss a day of working out (which she does for about three hours a day, every day), fasted.

Potentially addicted runners will cheat family time to run, sneak in runs without telling people, design vacations around exercise opportunities, will (if injured) count the days since their last run like an alcoholic counts the days since his last drink, and forgo sex to run (we often joke that nobody spends a Saturday morning running 20 miles because they have a great sex life). It seems certain that, if these symptoms are in any way common, running addiction will become an official disorder in due time.

The problem, from the perspective of these symptoms, seems quite real.

BUT THEN WHAT? IT’S hard to imagine how such “addicts” would be treated in a clinical setting. Would they be pushed to go cold turkey, as many drug and alcohol addicts are advised to do? That option would deny them the real benefits of a healthy activity they had merely taken too far. In the end, quitting could lead to a worse situation than the one the addict was already in. Scaling back, which is becoming an option for substance abusers, seems like it would be a more realistic option. But here, too, it’s hard to see how—given the tendency of the high to diminish for the exercise freak—the temptation to add one more mile could be resisted, especially when acute negative consequences do not result. It’s hard to imagine ever effectively treating this “disorder.”

In the course of writing this piece a friend asked me to pace him during the Austin Marathon, which I agreed to do. As our mileage reached a point where the body begins to yell back a bit—around 18 miles—I fell into thinking how unhealthy this activity was—a line of thought no doubt reflecting the reading I’ve been doing on exercise addiction. But then again, I wondered, why was I so deeply at ease with the world, in spite of the pain, as I moved through space for several hours? Contemplating the mysterious nature of this pleasure, something occurred to me that led to rethinking the whole idea of exercise addiction: Those we classify as exercise addicts might be a rare sort who are honoring what their bodies are designed to do and, historically, have done.

I don’t mean to simply regurgitate the Born to Run thesis so much as expand it to help better address the problem of exercise addiction. Consider that less than two hundred years ago life was predominantly agricultural. The sheer physicality of work was enormous. But men, women, and children did it every day. They had to. Was the Puritan work ethic enhanced with an endorphin rush? The Puritans aren’t saying. But it seems perfectly reasonable to hypothesize that the physical nature of life left pre-industrial people with a sense of bodily and mental equilibrium that, at the end of the day, they might have enjoyed. Today, by contrast, we spend most of our days sedentary while seeking to pathologize those who move around too much. And too many of us feel lousy.

What if the real addicts are those who seek to be sedentary—which could be just as unnatural as seeking to be drunk or high—while the crazed athletes are the ones who are seeking the deeper wisdom and capacity of the human body?