By Ryan Woolley
Lying awake in the middle of the night, I suddenly become acutely aware of my heart's rhythm. Tonight, I'm kept awake by its irregular moves - any jazz musician would have been proud to compose a piece to this beat. But, I don't want my heart to sound like it's moving along to a Herbie Hancock tune. I want it to feel like something closer to John Denver, and maybe while I'm running, I want it to jive with Led Zeppelin. It's an arrhythmia that I've been feeling a lot recently, and it's causing me some concern.
An inconsistent heartbeat seemed to be my body’s final cry for help after being trialed and tested throughout 2019. While I was intent on competing in the local track, road, and cross-country circuits, I also had my heart - literally and figuratively - set on exploring ultra and mountain events. While attempting to appease both the physical and mental requirements of each event, I lacked the focus required to take care of my body properly throughout the year. As runners, we rely on some sense of control and predictability, despite the chaos in which we exist. Adding too many variables to this chaos can topple a scale that already seems to sit precariously on the edge of success and failure - whatever that may represent for each of us.
This article is the first in a series that will explore the nature of what too much can look like in the running world. Each one of us is brave - we're fierce, and we're searching for more. But, what if, over months and years, we succumb to taking on more than we handle - mentally, physically, and emotionally? What are some of the subtle signs of too much, and how can we become mindful of what steps we need to take to avoid running and competing at our own expense? To begin, I'll explore two broad forms of impact that result from overtraining: heart arrhythmia and overtraining syndrome. In articles that follow, I'll be covering what other lifestyle-based influences can contribute toward how one responds to training and racing. Then, finally, I'll discuss what steps we can all take to remain healthy while continuing to feel passionate about our running pursuits. Above all, my intention is to start a conversation. When exploring a topic such as this, there are a myriad of intersections to cover. So, please - comment, question, or add your own story. Contribute whatever you feel could add some value.
Looking toward the Seaward Kaikoura Range, Summit of Mount Fyffe - South Island, New Zealand
Part One: The Heart of the Matter
We're raised to believe in several benefits associated with cardiac exercise: lowered blood pressure, lowered low density lipoprotein and cholesterol, lowered resting heart rate, increased cardiac output. This list of benefits became my ABC's while completing my undergraduate degree in Health Science. But, like most endeavors in life, these benefits exist on one side of a knife's edge. None of my professors spoke of what could occur on the other side.
Dr. James O'Keefe Jr., the Director of two Cardiac programs at the Saint Luke's Mid America Heart Institute, stood on top of the TED stage in 2012 to make the case for exercise in moderation. His talk opened with quoting the connotations of Pheidippides' fate after running 25 miles from the battlefield in Marathon to Athens to announce the Greek victory over the Persians. Shortly after his heroic effort, Pheidippides collapsed and died. This legend inspired organizers to set the distance of the 1896 marathon at 40 kilometers before the 42.2-kilometer distance was standardized in 1921 (fact check: Pheidippides actually ran from Athens to Sparta, which totals 140 miles. It was the Athenian army that marched 25 miles or so back to Athens to head off the Persian force approaching by sea).
While on the TED stage, O'Keefe draws attention to the "all-or-nothing" mentality that society upholds with endurance exercise. It's clear that a prolonged sedentary lifestyle can have a dramatic impact on various indices of health and wellbeing. But, Pheidippides' effort can be perceived as the other side of the coin: excessive amounts of endurance exercise (over 25 miles per week, running below eight minutes per mile), O'Keefe claims, can not only be counterproductive, it can also shave years off your life. Exposing the heart to greater than 60 minutes of intensive exercise causes excessive stretching within the cardiac chambers, which hampers its ability to adapt. Micro tears can start to form after repeated, sustained efforts. Over time, damaged cardiac muscle scars, thickens, and becomes stiff. In one study, marathoners with over 25 years of training and racing experience had developed 62% more plaque than controls, despite having fewer risk factors. Scarred and thickened cardiac tissue can create the ultimate recipe for atrial fibrillation, which can increase an individual's risk of heart failure.
Are you running too much? By O'Keefe's standards, most likely. He asserts that we're not born to run; we're born to walk. Protesting the ideas of the grandfather of evolution, he claims, "Charles Darwin was wrong. It's not survival of the fittest; it's survival of the moderately fit." I coughed up a part of the sandwich I was eating as he washed over this sentence. Then, I swallowed some pride. The miles, the hills, each tempo run - have I been doing it all wrong? Are we all living by the wrong standards?
Dr. O'Keefe isn't alone in his assessment; links between cardiac disease and high intensity exercise (sustained, high output activities such as running) have been reported anecdotally by athletes and within the scientific community for decades. In a review of the literature, Stergiou and Duncan (2018) assert that, although moderate forms of exercise reduce the risk of atrial fibrillation (AF), "sustained endurance training is associated with an increase in AF burden" (1). Though there are a vast number of variables to control for, it seems that the correlation between exercise intensity and AF risk continued to present as a U-shaped curve across several of the studies examined in the review.
Let's unfold a couple of layers and drill a little deeper. One study published in the American Journal of Cardiology gathered data from 60 non-elite male athletes who were scheduled to participate in the Grand Prix of Bern, a ten miler in Switzerland. Participants were split into groups according to the number of training hours they had accumulated during their sporting lives: low volume athletes had completed less than 1,500 hours; moderate athletes sat between 1,500 and 4,500 hours; and those considered high volume had completed over 4,500 hours. (As a point of reference, this final value is probably the equivalent of eight to ten years of consistent training for most distance runners.) From the low to high volume groups, several components of the cardiac system had changed. Notably, high parasympathetic tone and greater left ventricle mass, all of which are physiological changes expected to enhance performance. However, this group was also reported to, on average, have greater atrial volume and experience a higher number of premature atrial contractions within a 24-hour period - all of which are related to the development of atrial fibrillation.
Where does this leave us? Stop running? Run less? Run slower? Maybe. Or, perhaps, the health of the heart is only part of a much bigger picture. It is, after all, only one component of an incredibly complex system. Throughout your time as a runner, you're likely to have dealt with at least one of these components, something that may have felt as though it was the heart of the matter at the time. But, that's not what this article is about. At this stage in the series, I'm more interested in context. Let's take a step back.
Alpine meadow, Saint James Circuit - South Island, New Zealand
Part Two: “An Extreme Condition”
Running on Empty, was one of the first Jackson Browne songs I came to love. Through the lens of a man in despair, the song's lyrics recall easier days:
Looking out at the road rushing under my wheels
Looking back at the years gone by like so many summer fields
In sixty-five I was seventeen and running up one-on-one
I don't know where I'm running now, I'm just running on…. Running on empty.
There’s a monster in the closet of all highly trained endurance athletes. At first, you’ll notice something curious and unfamiliar shuffling around in the early hours of the morning. Then, as weeks go by, you’ll start to notice its shape and features. With the closet door now fully ajar, it casts a long shadow from the moon’s light. Its nails are long and hook-like... But, monsters aren’t real, right? And, besides, years of strong performances and tenacity should prove that, if there were to be a monster in that closet, it can be overcome by sheer will and determination! Monsters aren’t real! But, despite its vague and intangible nature, Overtraining Syndrome is – and it’s a subject that has captivated sport and exercise researchers for the past several decades. It also lurks in the shadows, and in the beginning, it’s easy to ignore.
Olivine Ledge, Humboldt Mountains - South Island, New Zealand
Anecdotal reports of Overtraining Syndrome (OTS) can be found across several popular publications. In Outside Online, Meagen Brown links it to a group of successful ultrarunners in her 2015 article, “Running on Empty”. Brown lays out how OTS has impacted ultra-runners such as Geoff Roes (previous Western States 100 record holder), Anna Frost (Hardrock 100 winner), Kyle Skaggs (previous Hardrock 100 record holder) and Mike Wolfe (2nd, Western States 100). Each of these anecdotes is preceded by a series of incredible performances followed by a sharp decline as they began to grapple with, and understand, the signs and symptoms of OTS. Providing later commentary on her research, Brown outlines the potentially insidious nature of OTS and its viral-like ability to latch itself onto the ultra-running community, noting symptoms such as: “bizarre” leg cramps, a loss of appetite, diminished libido, heart arrhythmias, and debilitating staleness.
Kreher (2016) defines OTS as, “...an extreme condition of maladapted physiology” where the hormonal, immunologic, neurologic, and psychologic systems fail to cope with and respond adequately to excessive exercise. Distinguishable from other degrees of training stress, such as functional and nonfunctional overreaching, OTS can require months before performance can recover despite proper rest. In this sense, Carfagno and Hendrix (2014) define OTS as “an accumulation of stress, due to training and additional life stressors, that results in long-term performance decrement.” Though the body responds favorably to well-timed doses of overload through exercise, excessive amounts without adequate rest cause various systems to become suppressed as they struggle to adapt.
One of these systems is the Hypothalamic-Pituitary-Adrenal (HPA) axis, which begins in the hypothalamus and ends in the adrenal gland. The HPA axis serves to regulate the endocrine response to stress. Under conditions of perceived stress and physical activity, it releases a flood of cortisol to prepare the body to “fight or flee” (or compete in a 100-mile foot race). Cortisol is responsible for aiding in the conversion of stored forms of energy (fat and protein) to a more accessible form, blood glucose. To bolster this function, and to make fleeing that much more effective in response to stress, the HPA axis goes all-in by suppressing highly demanding metabolic processes of the immune and reproductive systems.
In healthy athletes, the body’s response to stress is finely tuned. With training, it becomes more responsive to fluctuations in blood glucose. Though, as OTS begins to take hold, research suggests that this pathway begins to lose its potency at multiple points. In an overcooked engine, the hypothalamus, pituitary gland, and adrenal glands all become less responsive to exercise.
Cadegiani and Kater (2017) found that athletes experiencing OTS have blunted hormonal responses to exercise and stress compared to healthy athletes but not when compared to healthy non-active subjects. This suggests that, despite the HPA axis having the ability to adapt in healthy athletes, these adaptations are nullified in those affected by OTS. Though athletes affected with OTS are usually able to perform well in the beginning of any training load, this shift in response within the central parts of the HPA axis causes them to fatigue early while running at an otherwise standard intensity.
In a review article, Carfagno and Hendrix (2014) add a hypothesis that could explain the source of this change in the HPA axis. Paired with inadequate rest, repeated microtrauma to joint tissue sustained during training can shift acute inflammation to a chronic, amplified state. As the body struggles to return to a balanced state of healing, this chronic immune response can act on parts of the brain to decrease hunger, disturb sleep, and cause depression. This dysregulated state of repair can cause the body to permanently shift the balance of the central nervous system, causing a sustained activation of the HPA axis (stress response) while suppressing functions of the HPG (hypothalamic-pituitary-gonadal) axis, which is responsible for growth, repair, and reproduction. It seems that without proper caution we can quickly become consumed – literally and figuratively - by our desire to continue to do what we love.
Jackson continues to sing:
Gotta do what you can just to keep your love alive
Trying not to confuse it with what you do to survive
In sixty-nine I was twenty-one and I called the road my own
I don't know when that road turned into the road I'm on… Running on empty.
Valley of Beans Burn, Humboldt Mountains - South Island, New Zealand
I’m reminded of the need to place my life – my interests and passions – into a wider context. Is my focus too narrow? Perhaps I need to change the lens and adjust the aperture. For everything that running gives me, sometimes it can be difficult to step back and see how it affects – and is affected by - everything else in my life. Though I know that running is going to have an impact on the rhythm of my heart, I have suspicion that it’s only one part of a system that is more interconnected than I had once thought. May the research continue.
In the next article of this series, I’ll be considering what aspects of a runner’s life, beyond running itself, can have an impact on how our bodies and minds respond to our various adventures. This will involve exploring the purpose and use of the Hair Tissue Mineral Analysis test while exploring the root cause of some of the health problems described above. Here, I partner with Gary Moller, a Health Practitioner in Wellington, New Zealand to gather his thoughts on the matter.
Walker Ranch - Boulder, Colorado
About the Author
Raised in Hawke's Bay, New Zealand, Ryan Woolley is a distance runner with a passion for ultra and mountain events. He also has a love for guitar, banjo, drawing, and Quentin Tarantino films. He currently resides in Colorado with his partner, Roni, and dog, Henry.
References
Cadegiani, F. A., & Kater, C. E. (2017). Hypothalamic-Pituitary-Adrenal (HPA) Axis Functioning in Overtraining Syndrome: Findings from Endocrine and Metabolic Responses on Overtraining Syndrome (EROS)-EROS-HPA Axis. Sports Medicine - Open. 3(1), 45. https://doi.org/10.1186/s40798-017-0113-0
Carfagno, D. G. and Hendrix, J. C. (2014). Overtraining syndrome in the athlete: Current clinical practice. Current Sports Medicine Reports. 13(1), 45-51. http://doi.org/10.1249/JSR.0000000000000027
Kreher, J. (2016). Diagnosis and prevention of overtraining syndrome: an opinion on education strategies. Open Access Journal of Sports Medicine. 2016:7. http://doi.org/10.2147/OAJSM.S91657
Stergiou, D. and Duncan, E. (2018). Atrial fibrillation (AF) in endurance athletes: a complicated affair. Current Treatment Options in Cardiovascular Medicine. 20:98. https://doi.org/10.1007/s11936-018-0697-9
Wilhelm, M., Nuoffer, J., Schmid, J., Wilhelm, I., and Saner, H. (2012). Comparison of pro-atrial natriuretic peptide and atrial remodeling in marathon versus non-marathon runners. The American Journal of Cardiology. 109(7), 1060-1065. https://doi.org/10.1016/j.amjcard.2011.11.039