BEYOND COMFORT ZONES, FOR PERFORMANCE, WELL-BEING, AND LONGEVITY
John Ingham
Note: This article is concerned with preventing adverse consequences associated with endurance cycling while maximizing performance and health benefits. Do not take anything I am saying here as medical advice for self-care of existing conditions.
In my own training, I’ve been taught to look for the gaps: the gap at the end of
each out-breath; the space between thoughts; the naturally occurring,
nonconceptual pause after a sudden shock; unexpected noise; or a moment of
awe…
The fleeting moments of no-big-deal me, no internal conversations, no frozen
opinions, are very simple yet powerful. The utter freshness of just being
present introduces us to unshakable confidence: a lionlike pride that refuses to
buy into any negative or limiting story lines.
--Pema Chodrin, The Pocket Pema Chodrin (Shambala, 2008, p. 103).
Free your mind and your legs will follow. Your mind is your worst enemy. Do
all your thinking before you start riding your bike. Once the pedals start to turn,
wrap yourself in the sensations of the ride – the smell of the air, the sound of the
tires, the feeling of flight as the bicycle rolls over the road.
--Rule # 6, The Velominati: Keepers of the Cog.
I have often shared my view that the gravel experience, despite the pain and suffering - or more likely, because of them - is good for our physical and spiritual well-being. I have even suggested that cycling long and hard puts us on the path to awakening. This is not a perspective that some cardiologists and psychologists would endorse, however. James O’Keefe and his collaborators think that longevity gains level off and begin to decline with more than five hours of exercise per week. Extreme endurance exercise, they warn, increases risks for sudden cardiac arrest; atrial fibrillation; heart remodeling; myocardial fibrosis; and arterial calcification.1 Psychologists partial to this view—called the “reverse-J curve hypothesis” (or the “extreme exercise hypothesis”) ² - portray ultra-endurance exercise as an “addiction” seriously in need of psychotherapy. One dyspeptic psychologist - perhaps having nothing better to do - even opines that eating healthy food in support of high levels of exercise is also an addiction!
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| David Tubman and the author finishing the 2018 Filthy 50. (David Markman) |
It has been noted in reviews of the extreme exercise hypothesis, for example, that adverse consequences may reflect low levels of vitamin D and magnesium (common in athletes), and an overactive parathyroid gland,3 problems that can be easily remedied without giving up strenuous exercise. Magnesium supports muscle strength and endurance generally. Among other things it facilitates transport of electrolytes to heart tissue and uptake of vitamin D. Exercise depletes magnesium, and anti-nutrients in grain-based high carb/low fat diets interfere with magnesium’s absorption; vitamin D needs magnesium and fat for absorption. 4 At the same time, high fructose corn syrup and possibly other sugars, common in fueling endurance athletes, degrade vitamin D. Resulting vitamin D deficiency can cause blood calcium to fall, which in turn can cause the parathyroid to produce additional hormone (PTH). While this prompts bones to release calcium into the blood stream, it also causes high blood pressure, left ventricle enlargement, heart arrythmias, and calcification of heart valves and arteries, that is, the very adverse effects the proponents of the extreme exercise hypothesis attribute to exercise. 5 This hypothetical scenario, interesting it itself, alerts us to the possibility that there are yet other ways adverse health consequences may not result from exercise per se.
CARDIORESPIRATORY FITNESS
Evidence for the reverse J-curve occurs in inherently unreliable self-report studies. Moreover, samples drawn from the general population tend to be under-powered for assessing high- volume aerobic exercise. The percentage of people who exceed moderate exercise is small and the number logging ten to thirty hours per week is vanishingly small. In contrast, studies based on cardiorespiratory fitness (VO 2max ) and athletic accomplishment are together more objective and sample a wider range of exercise volume. Such studies find little or no evidence for an upper limit to the benefits of exercise:
- A study at the Veterans Affairs Medical Center in Washington D.C. that included 750,302individuals of both sexes, various ethnic groups, and many individuals in their seventies and eighties measured cardiorespiratory fitness (CRF) on a treadmill. It found a strong correlation between the objective measure of physical fitness and longevity; individuals with the least physical fitness had a mortality risk four times greater than that of extremely fit individuals. There was no increased risk associated with being extremely fit. 6
- A 2017 study by the Cooper Clinic looked at moderate to high CRF and triglyceride/HDL ratios in 40,261 men in relation to longevity. It found a significant positive relation between higher CRF and longevity and a significant negative correlation with triglyceride/HDL ratios, although a high level of CRF remained protective even when triglyceride/HDL was high. 7
- A 2018 study of 122,007 patients with an average age of 53 years tested for cardiorespiratory fitness on a treadmill. The researchers found that fitness is inversely correlated with mortality risk “with no observed upper limit of benefit.” “Extremely high aerobic fitness was associated with the greatest survival.” 8
- A study of 5,107 middle-aged men from the Copenhagen Male Study found a strong, positive linear correlation between CRF and longer life, the benefits of fitness extending into later years. The maximal life extension of nearly five years was observed among the men with the highest CRF. 9
- A study of 2,613 Finnish athletes who had participated in at least one international event found that most of them lived longer than a control group of non-athletes. Among various types of athletes, the Nordic Ski and long-distance runners had the greatest gains in longevity—about six years and tended to be free of cardiovascular disease and diabetes as they aged. 10
- A study of 834 cyclists who participated in the Tour de France between 1930 and 1964 found they lived 17% longer than matched people in the general population of France, or 81.5 years instead of 73.5. According to the authors, cyclists should not fear harm from riding to exhaustion when they are well trained. 11
- Another study compared ages of death with general life expectancy for the first twenty runners who broke the four-minute barrier for the mile run. Eighteen of the 20 surpassed expected life expectancy by an average of 12 years. 12
- A meta-analysis of 165,000 male and female elite athletes found that male endurance athletes have a 31% reduction in mortality risk and females a 49% reduction. The authors conclude that there is no evidence for a reverse J-curve in their data. 13
There is a caveat. About 50% of VO 2max or cardiorespiratory fitness is inherited, and VO 2max alone may be the best predictor of cardiovascular disease. This suggests that elite athletes live longer simply because they have better genes. This is no doubt partly the case, but genes are not the whole story. For one thing, the usual estimate that exercise accounts for 15 to 20% of VO 2max is probably too low. Alan Couzens has found in his lab that large volumes of zone 2 exercise produce an average increase of 24%, with some individuals achieving as much as 40%. 14
Moreover, VO 2 max is not the biggest factor in elite performance. A high VO 2max is a prerequisite for above average endurance, but it does not ensure outstanding performance. Elite performance depends on lactate threshold, which is determined more by exercise volume. And consider that VO 2max varies by a factor of about two, from the sedentary to elite athletes, whereas exercise volume varies by a factor of 20 to 30. If adverse effects of exercise were simply a result of high volumes of exercise, elite athletes would not be living so much longer than most people (see Genes).
THE RISKS
The risks associated with large volumes of exercise are serious, but they may not be as high as the supporters of the extreme exercise hypothesis would have us believe. Evaluations of the hypothesis by medical experts note the following: 15
- Sudden cardiac death triggered by exercise is extremely rare.
- Heart enlargement and myocardial fibrosis are found in some endurance athletes. How much is a reversible effect of training and how much is pathological are uncertain, as are long run consequences.
- Increased artery calcification occurs in many older endurance athletes. Calcification is usually a good marker of cardiovascular risk but not in endurance athletes.
- Risk of atrial fibrillation increases as exercise becomes extreme, perhaps two to tenfold,a concerning finding since atrial fibrillation increases the risk for heart attack and stroke.
- The benefits of high levels of exercise outweigh the risks. Overall, the evidence for a reverse J-curve falls short of establishing an upper limit for aerobic exercise.
TRAINING, RECOVERY, AND REST
Coaching and training ensure adaptation to stress. Pro cyclists and many amateur cyclists have coaches and follow training regimes that include large volumes of low intensity riding; intervals; ample sleep and recovery time; care to prevent over-training; healthy diets; and adequate fueling and hydration. Endothelial dysfunction and oxidative stress or reactive oxygen species (ROS) are at the root of cardiovascular problems in extreme exercise. Progressive training with adequate rest and recovery improves endothelial function and the body’s mechanisms for detoxifying ROS. The point at which oxidative stress becomes harmful is what is at issue in this and other discussions of the extreme exercise hypothesis. 16
Some weekend athletes may be trying to improve fitness too quickly at counter-productive intensities. A recent article in Cell Metabolism finds that daily or near daily HIIT exercises or intervals cause mitochondria to become dysfunctional, resulting in glucose intolerance and insulin insufficiency. The same pattern was found in a sample of world-class endurance athletes. Interestingly, though, systemic oxidative stress did not increase, and glucose sensitivity returned quickly to normal levels with less intensive training. The authors do not recommend against HIIT or interval training. Occasional intervals promote mitochondrial function and beneficial nitric oxide. The temporary mitochondrial dysfunction in the study may be part of how physiological stress, within limits, is a normal part of training. The authors interpret their results as suggesting that athletes should be careful about not overtraining, not as an argument against intense exercise. 17
HITT and intervals can raise VO 2max quickly, but bigger gains can accrue more safely over time from large volumes of easy aerobic exercise. This is so because high volumes of low intensity exercise increase cardiac stroke volume and because peripheral mitochondria increase in response to the number of contractions, not to the intensity of exercise. 18 These findings support polarized training where large volumes of training are devoted to zone 2 and a much smaller portion to intense cardio workouts, say in a ratio of 80 to 20. The large volume of zone 2 exercise supports performance in all zones because it improves the shuttle of lactate in fast twitch muscles to slow twitch muscles, thereby reducing fatigue from all-out efforts while providing additional fuel for the slow twitch muscles. Zone 2 exercise supports not only performance but also cardiovascular health and longevity (Inigo San Millan).
Participating in ultra-endurance events with insufficient training can also have adverse consequences. The high DNF rates in gravel races suggest that too many gravel riders are ill- prepared for ultra-distance events. Long gaps in training weaken strength and resilience, more quickly than one might think. And this is especially true for cardiorespiratory fitness. VO 2 max, for example, can drop about five percent in a one-week layoff.
DIET AND FUEL
Diet and fueling may be the big elephant in the living room when it comes to adverse effects of high levels of exercise. Much of the obfuscation no doubt results from the Diet-Heart Hypothesis that has informed cardiology and national diet guidelines for fifty years. Tim Noakes, the author of The Lore of Running, the “bible” on carbohydrate loading and fueling for endurance sports, now regards his book as a huge mistake that was influenced in part by the Diet-Heart Hypothesis (Noakes).
According to the Diet-Heart Hypothesis, dietary fat causes high cholesterol and high cholesterol, especially high LDL, causes cardiovascular disease. Statins became the treatment of choice for high cholesterol despite their side-effects, which include muscle weakness, increased risk of diabetes, and in the long-term, possibly hardening of the arteries and cardiomyopathy. 19
In fact, the Diet-Heart Hypothesis is in trouble. Since the 1960s studies have shown that
consumption of saturated fats increases cholesterol but not the incidence of heart attacks. 20
The 18-country PURE study found that carbohydrates are associated with all-cause mortality
whereas fats were associated with lower mortality; total fat was not associated with
cardiovascular disease or heart attacks. 21 A meta-analysis of recent diet research confirms that
carbohydrate restriction improves cardiovascular risk factors. 22 Recall from the Cooper
Institute study that a low triglyceride/HDl ratio was associated with lower heart disease risk. In
fact, a low triglyceride/HDL ratio is one of the best markers of a healthy cardiovascular system.
The ratio is made worse by a high carb/low fat diet and better by a low carb/high fat diet. A
recent meta-analysis of LDL-cholesterol and statin studies in the Journal of the American
Medical Association found that statins have only a modest ability to prevent cardiac events and
that lowering LDL with statins has little or no benefit. Putting the statistics in terms of “numbers needed to treat” makes this clear: to prevent one heart attack, it takes treating 77 individuals with statins for 4.4 years. 23 (The small benefit of statins may result mostly from an anti-inflammatory effect and from the way statins promote calcification over soft plaque.) A telling blow to the Diet-Heart Hypothesis is emerging in a study underway by David Feldman and colleagues that is measuring cardiovascular disease with the CT Cardiac Calcium Scoring test, one the most objective and accurate ways of measuring the extent of coronary artery disease. They are evaluating athletic, super lean men and women who are responding to low carb/high fat diets with extremely high cholesterol and LDL. Yet preliminary results are showing that these lean body-mass hyper-responders have little or no coronary artery disease (Feldman). 24 It appears that Timothy Noakes, Jeff Volek, and Stephen Phinney were ahead of their time when ten years ago they suggested that high consumption of sugar and carbohydrate may be why some endurance athletes develop heart disease. 25
The latest iteration of the Diet-Heart Hypothesis argues that red meat is harmful to health, especially cardiovascular health. According to this view, everyone would be better off on a plant-based diet. A recent meta-analysis of large-sample studies that investigated risks associated with red meat, however, finds that the evidence impugning red meat is so thin that it probably should not affect dietary choices. 26 In fact, red meat contains various vital nutrients absent in plants.
Taurine, a sulfur-based free amino acid found in animal food and fish is one of the most interesting of these nutrients. The body gets most of its taurine from meat and fish, although it has a limited ability to synthesize taurine from proteins found in plants as well as animals and fish. A landmark paper in the June 2023 issue of Science suggests that the usual decline of serum taurine with age in mammals (including humans) is a principal driver of aging, and that supplementing with taurine might extend life. Of particularly interest to here, the paper that includes a study that finds that exercise increases serum taurine, and suggests that this effect may partially explain the longevity benefit of aerobic exercise. 27 A few studies with animals and small-sample human studies also suggest that taurine improves muscle strength, muscle recovery, and time to exhaustion in aerobic exercise, although the results are mixed and inconclusive. 28 As one might expect, these findings have drawn skepticism, especially from Diet-
Heart Hypothesis/plant-based diet advocates. It will be interesting to see whether more human studies provide more clarity about taurine benefits.
Anthropology supports and illuminates these findings on diet. We surmise from recent hunter- gatherers that our ancient hunter-gatherer ancestors rarely suffered from cardiovascular diseases despite large volumes of long-distance walking and running and omnivorous diets that were often much higher in fats and lower in carbohydrates than most modern diets. Since they often depended heavily on game animals, their diets would have contained ample amounts of taurine and other nutrients found only in animal food. The diets often included smaller amounts of tubers, nuts, seeds, fruits and honey but lacked added sugar, high glycemic, highly refined grains, and inflammatory vegetable oils. In other words, they were also included plant micronutrients and yet had small amounts of the phytates and lectins in grains and legumes that can block absorption of micronutrients. Unlike corn- and grain-beef, their grass-fed game contained large amounts of K2, a vitamin that activates proteins that guide calcium away from artery walls and other soft tissue and into bones and teeth. Paleolithic meat also had fewer inflammatory omega 6 and more anti-inflammatory omega 3 fatty acids and a healthier mix of saturated fats.
Diets clearly took a big turn for the worse with the agricultural revolution and, even more so, with industrialized and processed food in the last hundred years or so. Sugar-heavy and refined flour diets increase the risk of heart disease by about 30% and stroke up to nearly 50% (all carbs turn into glucose after digestion). Sugar causes immediate acute dysfunction in the endothelial linings of blood vessels. Endothelial dysfunction can then lead to chronic processes that result in atherosclerosis. Hyperglycemia also promotes artery calcification. Spiking blood sugar together with exercise-induced stress may be especially likely to promote arterial calcification. 29
As noted above, many long-time endurance athletes have more than the usual artery calcification. Ordinarily, arterial calcification indicates cardiovascular risk, but this is less so in endurance athletes, probably because they have less soft plaque under calcification (a possible mechanism here may involve higher levels of HDL resulting from exercise. HDL can absorb some of the LDL in plaque and return it to the liver). Even so, it would be better to have no plaque and no calcification. 30 Aerobic exercise at moderate intensities can mitigate endothelial dysfunction. 31 But the time required for exercise to level spikes in blood glucose while the body is under stress may be when fueling with carbs and sugar is most harmful. My guess is that carbohydrate loading and fueling with sugary drinks and gels are at least partially responsible for the plaque and arterial calcification seen in some endurance athletes.
Atrial fibrillation (AFib) is another serious concern, but in its case too there are reasons to suspect that exercise is not the real culprit. Electrolyte imbalances may play a role, especially too little magnesium. 32 Some evidence implicates oxidative stress from sugar and purines in atrial fibrillation. Purines break down into uric acid which can trigger AFib. Fructose breaks down into purines (orange juice is high fructose, while beer is high in purines). 33 Oxidative stress may be the final common pathway to Afib. Various studies have found that elevated oxidative stress is significantly associated with AFib. 34 Both magnesium deficiency and sugar cause oxidative stress. The uric acid produced by purines is antioxidant in plasma, but it has pro-oxidant properties in cells and, in fact, is associated with cardiovascular disease. 35 The increasing cardiovascular risks associated with higher levels of exercise could be an artifact of how healthy and sufficient training, sleep, recovery, diet, and fueling become more consequential as exercise volume increases.
PREVENTION AND PERFORMANCE
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| Racing is a social sport. The start line of the 2023 Filthy 50 (David Markman) |
Many exercise nutritionists still promote sugar and carbohydrates for athletic performance. The contention that carbohydrates are better than fat, however, is hardly overwhelming, and it typically ignores what is now known about the health risks associated with sugar- and carbohydrate-dependent diets. While carbohydrate loading and fueling may have an advantage at maximal effort, fat-adapted athletes do quite well at sub-maximal effort. Research also shows that they burn fat very efficiently even at the highest levels of effort, and that they can switch to fueling with carbs without compromising fat burning efficiency. 36 The debates about whether carbohydrate or fat is better for performance are heated, but they are a bit like a tempest in a teapot for most gravel riders and racers—many studies show that there is little performance or VO 2 max difference between the two macro-nutrient strategies. 37
This said, it is hard to go without sugar and carbs in endurance events. Even ketogenic athletes find that they need sugar at some point in ultra-endurance events. There are ways, however, to reduce the risks of sugar and carbs during training and races. One approach reduces high glycemic carbohydrates during training but allows them during events. An endurance sport supplement company boasts about the maltodextrin (a refined carbohydrate) in its gels, while damning fructose and table sugar as unhealthy. This sounds good but in fact maltodextrin spikes blood glucose and insulin even more than sugar. Big spikes in blood glucose are better avoided by simply spreading sugar out in smaller amounts. Or we can try fueling with low glycemic carbs. And we may need less sugary fuel than we imagine. Timothy Noakes finds that falling blood glucose is the proximate cause of bonking, not muscle glycogen exhaustion, and that only 5 to 20 grams of sugar per hour are required during performance to maintain normal blood glucose levels. 38
Oxidative stress and inflammation during intense exercise can also be moderated with antioxidant and anti-inflammatory snacks, drinks, and supplements (e.g., blue berries; red grapes; tart cherry juice; nuts; dark chocolate; coffee or tea; vitamins C, E, and A; CoQ10; magnesium; taurine; n-acetyl carnitine; quercetin; resveratrol; curcumin; melatonin, etc.). 39 Antioxidant supplements, however, can interfere with adaptation of muscle tissue to stress, so it may be better to take them in small amounts or not at all during training. (Note: Some nutraceuticals interfere with medications; follow dose recommendations and consult with your doctor if you have a medical condition.)
After an engaging review of the relevant literatures, Alex Hutchinson concludes that performance depends not only on training, diet, and fueling but also on elusive mental qualities like grit, courage, confidence, etc. 40 They may be critical for health and longevity as well. Stress was once thought to be uniformly bad for emotional and physical health, but more recent research is exploring how it can be good for us, that is, how stress can prompt “hormesis,” a process of becoming stronger and healthier during adaptation to adversity. Whether stress is harmful or beneficial can turn on positive emotions and attitudes, including I will suggest on how much we transcend egocentric preoccupations with the self. 41 Putting matters this way poses fundamental questions about the nature of mental, emotional, and spiritual health.
MIND-SET
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| The author by the St. Louis river contemplating Lao Tsu's "Flow".(Mary Grove) |
Cardiovascular damage during extreme exercise may be less likely when it is not just about personal success, and when the ride itself is enjoyable, when we ride with friends, and when we are riding in beautiful places. The 80-year-long prospective Harvard study has shown that living with a beloved partner and having many friends have a huge effect on well-being and longevity. By the same token, exercise in groups is more beneficial than exercising alone. 42 Numerous studies find that being in nature also improves health and well-being. 43
These observations make sense in view of human evolution and how the mind is organized. Neuroscientists have identified two opposing but interconnected neural networks, the Default Mode Network (DMN) and the Task-Positive Network (TPN). The two networks are mutually inhibiting; when one is active the other is inactive and vice versa. Roughly speaking, the DMN supports the ego, whereas the TPN supports attention to tasks and the outside world.
The DMN is active during mind-wandering and dreaming. Thoughts are self-referential, featuring memories about status or reputation in social situations, regrets about the past or forebodings about the future (“self” here refers to thoughts and stories about the self, not to consciousness, which is sometimes referred to as the “true self”). The DMN’s basic function may be constructing and updating automatic unconscious responses to recurring situations and events, especially perhaps approach/avoidance conflicts. A few years ago, I published a paper about dreaming in which I argued that dreaming is an evolved system for working out solutions for emotional conflicts, especially those between love and danger. 44 Whether such solutions in dreaming and daydreaming are fearful, or hopeful may depend importantly on what the DMN has been learning in crosstalk with the TPM. At its best, the Default Mode Network underlies wisdom and judgement in dealing with life’s conflicts, dilemmas, and conundrums. In so during, it supports creative thinking and underlies myth, literature, art, and philosophy. It tends to be a bit moody, however, especially when it lacks input from encouraging experiences of the outside world. When overactive and unrestrained by the Task Positive Mode, its moodiness can lead to addiction and depression. 45 Depression in turn is linked to various chronic conditions, including cardiovascular disease.
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| "Non-Racing" racing. Toilet Stop on the 2023 Filthy 50 course. (David Markman) |
The Default Mode Network is oriented toward self-preservation. The Task Positive Network copes with external danger also, but rather by transcending the self and grabbing the bull, as it were, by the horns. It copes with external stress by leaning into it with courage rather than withdrawing from it with trepidation. Transcendental experiences involving deactivation of the DMN, 46 unfold on a continuum from flow, to awe, and finally to awakening.
Flow is effortless action that occurs at boundaries between maximum challenge and risk of failure, on the one hand, and full use of skillsets and intense focus and purpose, on the other. The autobiographical self disappears as one becomes engaged in the task at hand. Flow is an end itself; any ulterior purpose remains in the background. It is often recalled as the most satisfactory experience people have ever had. Flow was described by Lao Tsu, an ancient Taoist philosopher. Among other things, he called it “effortless effort.” He likened it to water flowing downhill.
Awe also occurs on the transcendental continuum. One is moved by majesty and natural beauty in nature, sometimes with a touch of trepidation—awe-inspiring places are often dangerous and daunting as well as beautiful. In the presence of sublime scenes and spectacles, self-importance can vanish as we realize that society and nature are much grander than ourselves, and as beauty overwhelms our fears and self-concerns. Evolutionary psychologists speculate that the extraordinary human capacity for awe expresses an evolved sense of gratitude for community and nature.
Awakening can happen in a momentary flash of brilliant light or, more often, little by little. Movement toward awakening is more likely in what Buddhists call “the bardo” moments. Bardo can take the form of commonplace “gaps” when nothing is happening, or our minds go blank. Life-transforming bardo is more likely in unfamiliar situations like near-death experiences, catastrophic loss, long pilgrimages through unfamiliar countryside, or when in forests, deserts, or high mountains.
The principal features of awakening are dissolution of the ego and, by same token, a sense of deeper connection with other people, nature, and the cosmos. The state is also associated with openness, curiosity, courage, compassion, tranquility, pain tolerance, and in some cases greatly reduced fear of death. It is not difficult to see that these additional qualities may be facets of reduced preoccupation with the self and increased sense of connection with other people and nature. After a period as a wandering monk that deprived him of the comforts and attention he had acquired as a revered teacher, one Buddhist likened his waking up to “being in love with the world.” 47
Effortless effort resembles what I have called “non-racing racing” or “racing that is not racing.” It happens when we are focused less on personal achievement and more on riding itself. Paradoxically, this transcendence of the self is more likely to improve performance than not. It is the optimum state of matching skill to challenge. The qualities of calmness, courage, and pain tolerance associated with the transcendental continuum also enhance performance.
Gravel requires mental toughness, resilience, confidence, and the like, but it may also be that gravel nurtures the very qualities it requires. The long, demanding ride can facilitate elements of awakening. During a long ride, we slip in and out of flow, and there are moments of awe, and bardo-like moments, as when we make a wrong turn in the middle of the night and find ourselves utterly lost, when exhausting effort in extreme cold or heat leave us feeling completely humbled, or when intense pain and suffering take us into very dark holes. These experiences may dissolve the self by promoting humility, by encouraging compassion for ourselves and other riders, or by enhancing consciousness and perception. In so doing, they strengthen bonds with companions and enhance connection with the world. At work in bardo moments, too, may be how adversity makes us stronger and healthier when we confront it with determination and courage.
“Falling in love with the world” on the path to awakening is more than a metaphor. The “love” hormone oxytocin supports pair-bonding, parenting, and friendship, but it is relevant here in other ways as well. Along with a handful of other feel-good hormones, it is elevated in the flow state and when viewing natural beauty or works of art. It increases with exercise, and it is the trigger that shifts the mind from the Default Mode to the Task Positive Mode. Oxytocin increases as we cope successfully with stressful situations and then energizes us to cope with further stress with even more courage and resilience. 48 Love can even mend a broken heart, literally as well as figuratively. Ordinarily, when heart tissue dies from lack of oxygen it becomes fibrous and dysfunctional. In human beings the endogenous mechanisms for healing a damaged heart are strongest when people are feeling loved. Oxytocin is by far the most powerful hormone that can move stem cells from the periphery to the center of the heart
where they can seed renewal of damaged tissue. 49
About two million years ago the earliest humans went through evolutionary changes that enabled persistence hunting, and strenuous foraging for plant food, not just by young men, but by females as well as males, and by young and old alike (not coincidentally, both males and females are capable of long-distance walking, jogging, and running into early old age). The primeval diet supported this active lifestyle. But there is more to the story. About six to seven million years ago, as widespread forests were drying up in Africa, a group of anthropoid apes split off from the chimpanzee-like Last Common Ancestor, came down from the trees, and began foraging on open ground. The more open woodlands and the wide-open savanna were full of big cats, huge snakes, and giant baby-snatching raptors. Early hominids were small but survived by becoming more loving, social, cooperative, courageous, clever, and alert than the ape cousins they had left behind. As they foraged farther from camp, an evolving bipedal locomotion made carrying babies, plant food, and butchered game easier. Much (but not all) of the aggressiveness, sexism, selfishness, and promiscuity of the Last Common Ancestor gave way to pair-bonding, paternal recognition and care of offspring, ramifying kinship relations, and mutual support and food sharing between genders and families. 50 No other species comes close to this degree of love, sociability, and cooperation. We were born to run (or cycle) long distances, but we were also born to explore the unknown despite its dangers, to eat wholesome food, and to love, share, and cooperate. And we were born to experience awe and connection with more than ourselves.
Riding and racing gravel recoup features of the ancestral hunter-gatherer way of life. They involve endurance exercise, challenge, comradery, and they take us into nature. With all due respect to well-meaning proponents of the extreme exercise hypothesis, their misgivings should not dissuade us from riding long and hard. Having found a way back to the garden and the better angels of our nature, we are not about to give up our bikes for walking the dog around the block, at least not yet. We are willing to take some risks. Life is an adventure after all. Encouraging each other while moving into the difficult unknown, is our birthright. It is who we are.
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