Exercised - Book Summary

Rediscovering the true meaning of staying fit: a glance through evolutionary history

Let's face it, the mantra "exercise more" has almost become a universal chorus echoing through gyms, offices, and online forums alike. Our culture is saturated with the belief that physical activity is the silver bullet for combating a plethora of issues from obesity and mental health to fatigue and various diseases.

But as well-intentioned as this advice is, it often comes wrapped in confusion and contradiction. Take running, for example. Sure, it's celebrated as a cardiovascular king, yet there's that nagging worry about worn-out knees. And the age-old "eight hours of sleep" rule is challenged by the countless who spring out of bed after only seven.

To slice through these mixed messages, we turn to a two-pronged approach that marries the wisdom of our ancestors with cutting-edge contemporary studies. What emerges is a rejuvenated perspective that weaves together the best of both worlds, breathing new life into our understanding of what it means to live - and move - healthily.

In this journey through anthropological insights and scientific discoveries, you'll uncover fresh answers to common queries, such as:

Do we really need a full eight hours of uninterrupted sleep to thrive?

Did evolution skimp out on making us naturally strong and muscular?

Can a simple walk be the underrated hero in our quest to shed those extra pounds?

Join us as we traverse time and scrutinize science to reshape the narrative around exercise and wellness, navigating a path that feels both novel and as old as humanity itself.

Tracing the roots of our relationship with physical activity

Picture our ancient forebears — always on the move: hunting, gathering, trekking across vast terrains, and yes, sometimes engaging in skirmishes that demanded agile and robust physiques. It seems only logical to think that they were exercise incarnate, living out a life of constant activity out of sheer necessity.

And yet, if we dig a little deeper into our evolutionary journey, we come across an intriguing revelation: when it comes to exercise, we're not the natural enthusiasts we might think we are.

Here's the crux — exercise is not an innate drive implanted by evolution.

Broadly, we may associate exercise with any physical activity, but there's a distinction to be made. Exercise refers to intentional movement done specifically for health and physical fitness. Our evolution, on the other hand, nudged us towards activity driven by necessity, not for the fun of it. Sure, there have been exceptions — dance and play have always been part of our cultures — but these are the outliers, not the standard.

Our reluctance to commit to unnecessary exercise offers an insight into our primal instincts. After all, engaging in physical exertion saps energy, and for the vast majority of human history, energy — or rather, the food that provided it — was in scarce supply. Unlike today where calories can be easily replaced, back then, unnecessary energy expenditure could mean the difference between survival and peril.

So if you find yourself dragging your feet at the thought of hitting the gym, take solace in the fact that this resistance is essentially written into our DNA. Our ancestors' lives depended on conserving energy, making economy of movement more valuable than we can probably comprehend from our modern standpoint.

Does this mean hanging up our running shoes for good, in the spirit of ancestral wisdom? Absolutely not. Instead, acknowledging this historical context helps us understand why maintaining a fitness regimen can feel like an uphill battle, and reminds us to practice patience and compassion with ourselves and others when it comes to leading an active lifestyle.

In essence, let’s drop the stigma surrounding exercise reluctance and recognize the triumph in every step taken against the grain of our most primal instincts.

Debunking the eight-hour sleep myth

We're in what seems like a modern slumber conundrum. Everywhere we look, sleep experts are sounding the alarms: we're just not getting enough Zs. The story goes that once upon a time, our predecessors basked in luxurious ten-hour sleep cycles, while today, we're lucky to snatch seven — falling woefully short of the prescribed eight. With whispers of a sleep deprivation “epidemic” hurting our health, encouraging car accidents, and dulling our work performance, the concerns are real.

But should we take these declarations at face value, or is there room for digging deeper into our sleep cycles?

Let this sink in: We don't all need eight hours’ sleep.

The origins of this eight-hour sleep edict are somewhat murky and more cultural chant than scientific dictum. The idea can be traced back to the catchphrase of nineteenth-century factory workers, advocating for balanced divisions of the day: "Eight hours for work, eight hours for rest, eight hours for what we will!" Although catchy, this slogan makes a shaky foundation for sleep science.

Enter Jerome Siegel and his research colleagues at UCLA, who decided to unravel the threads of our sleep patterns by closely observing traditional societies — hunter-gatherers and hunter-farmers in locales from Tanzania to the Amazon to the Kalahari. Their findings were eye-opening: these groups enjoyed less sleep than their modernized counterparts, averaging around six and a half hours, fluctuating slightly with the seasons.

Further studies involving Amish farmers and subsistence farmers in Madagascar echoed these findings, demolishing the notion that natural sleep should stretch for eight uninterrupted hours. Even more provocatively, research suggests that the seven-hour sleepers might just have the edge, correlating with longevity more so than their longer or shorter sleeping peers.

So if you've been tossing and turning over sleep recommendations, it's time to ease those furrowed brows. While achieving the 'recommended' eight hours may not be the mark of sleep success, incorporating daytime exercise could pave the way to more restorative nights. Embrace your natural sleep rhythm — it might be just what your body has been craving all along.

Myth-busting: Our ancestral strength was practical, not Herculean

When we conjure images of our hunter-gatherer ancestors, many of us imagine rippling muscles and formidable strength, the type befitting characters in a prehistoric epic. Advocates of primal fitness regimes hold the belief that routine activities like wrestling wild beasts and heaving stones sculpted our forebears into paragons of human power.

The modern couch-bound lifestyle, they argue, has stolen this robust form from us — and now, it's our duty to reclaim our birthright of brawn.

But does this line of thinking align with the facts?

Let's set the record straight: We didn’t evolve to be naturally brawny.

Reality paints a different portrait of our foraging forefathers, one not characterized by exaggerated muscularity but by modest strength and leanness — think survival-fit, not bodybuilder-imposing. If you observe the Hadza of Tanzania, a surviving hunter-gatherer tribe, you won't find monstrous musculature. Their physical prowess lands squarely within the parameters of average Westernized populations.

This moderate build holds true across a spectrum of contemporary traditional societies — from Africa's Mbuti to Paraguay's Aché — fitter than many in the industrialized world, yes, but not equipped with the kind of muscle mass that inspires awe.

How about building muscle with nature's equipment? Well, training with only your body weight, while beneficial for fitness, hits a plateau since increasing strength becomes a harder target to push as your own body weight remains constant. Gym gear and techniques that amplify muscle gain are comparatively recent human inventions.

Evolutionarily speaking, the case for humankind as naturally bulky beings further crumbles when you consider the metabolic cost of muscle maintenance. Roughly one-fifth of our caloric intake serves just to keep our muscles in working order; any increase in muscle mass proportionally guzzles more energy, a luxury our ancestors couldn't afford.

The evolutionary calculus here is simple: muscle mass beyond that which was required for day-to-day survival and occasional confrontations wasn't worth the additional metabolic expense. In essence, utility won out over bulk — we were engineered to handle life's rigors effectively, not to flex superhero-sized biceps for the Gram.

So, before you start comparing your physique with that of a marble statue from antiquity, remember that evolution favored balance — strength sufficient for survival, not enough to grace a bodybuilding stage.

Walking: A step in the right direction for weight management

When it comes to exercise and weight loss, few questions ignite as much debate among researchers as the effectiveness of walking. It seems reasonable — step up your walking game to burn calories and tip the scales of energy balance towards fat loss, and voilà, you slim down. However, skepticism lurks in the scientific shadows, suggesting that a stroll around the park might be an inefficient tactic for tipping the scales.

So what's the skinny on walking and weight loss? Should our sneakers be reserved for runways rather than runway models?

Here's what's worth putting one foot in front of the other for: Walking does have a role to play in weight loss.

Those who cast doubt on walking's weight-loss benefits point out that walking is a bit of a calorie miser and can trigger increased hunger, leading to a calorie intake that effectively cancels out the calories burned. This view gains traction with studies showing minimal weight change when overweight individuals incorporate a moderate increase in walking without dietary changes.

Yet, our bodies are marvels of motion efficiency, and walking is a pinnacle of that evolutionary excellence. It's an activity we've honed to require minimal energy; great for endurance, but an obstacle for those trying to shed pounds through walking alone.

However, where there's will — and walking — there's a way. Research indicates that doubling down on the duration, with brisk walks adding up to 300 minutes per week, can indeed shift the weight needle. The results aren't jaw-dropping on their own, but patience pays off — persistence can accumulate to significant weight loss over time.

More than being a tool for weight reduction, walking shines as a champion of weight maintenance. Crash diets often see a weight rebound where intermittent exercise is absent, while individuals pairing weight loss with regular walking are likely to keep the pounds off for the long haul.

Walking isn't a one-size-fits-all solution for weight loss, but it's a contributor that can't be underestimated. It's an accessible, sustainable step forward towards not just reaching a target weight, but remaining there too. So lace up those walking shoes — each step counts towards maintaining a balance on the scale and in your life.

Pounding the pavement without pounding your joints

Stepping up from the gentle stride of a walk, running is the next echelon for many seeking to elevate their fitness. More than just a workout, for some, it’s virtually a rite of passage — but it's also a source of trepidation, cast in the grim anecdotes of long-time runners nursing injuries and chronic pains.

Is this fear justified? Does lacing up for a run inevitably set you on a collision course with injury?

Consider this reassuring insight: Running doesn’t have to lead to injuries.

The fear of running-related injuries isn't unfounded — runners do end up on the sidelines from time to time. Yet, the injury rates don’t surge evenly across the board; rather, they trace a U-shaped curve where novices and running zealots tend to be more injury-prone, while moderate runners enjoy a smoother ride.

Moreover, let's debunk one of the biggest myths shadowing the tracks: the belief that running invites osteoarthritis through relentless joint strain. The evidence rallies against this notion, showing that running can actually foster cartilage health rather than its breakdown.

However, acknowledging that running occasionally does cause injuries, the next step is understanding how to sidestep these hazards. The key is pace — not in your step, but in your progress. A runner's enthusiasm is like kindling to a flame — necessary, but too much too quickly can burn down the whole endeavor. Adhering to the ten percent rule, where you cautiously increase distance or speed weekly, is a strategy that helps stave off injury by allowing the body to adjust.

The body's potential for adaptation is remarkable, as witnessed by the author while tracking eight runners on their grueling 3,080-mile journey across the United States. Their initial experiences were a patchwork of aches and injuries, but as days rolled into weeks, their bodies found a rhythm, toughened by the daily marathon distances. Remarkably, the spate of injuries clustered in the first month, with the final month sailing by injury-free.

This evolutionary flexibility highlights an empowering narrative — that running, a primal activity we're naturally designed for, can be approached with confidence rather than caution. With gradual conditioning and a respect for our body's adaptability, running can be a joyful, injury-minimal pursuit, threading fitness into the fabric of our day without the looming threat of harm. So go ahead, take that run — your journey might just be clearing the air of myths with every ground-covering stride.

Active aging: The secret to a robust twilight

Envisioning retirement often conjures images of leisure, rest, and well-deserved tranquility. However, the lifestyles of the elderly in hunter-gatherer communities could reshape our expectations of the golden years.

Consider the Hadza of Tanzania, a continuation of the theme we've explored before. When contrasted with the declining physical activity of Americans from their forties to their seventies, the Hadza's gradual and less pronounced activity decline is striking — they maintain their strength and vigor well beyond the years we typically associate with frailty.

Hunter-gatherers don't just enjoy enviable physicality in their later years; their longevity, often reaching into the seventies, rivals that of places with modern healthcare, despite their lack of it. So, what pearls of wisdom can we glean from their enduring vitality?

Here's what we should take to heart: We need to stay active as we age.

Research into geriatric health among traditional societies indicates that the "diseases of aging" we accept as standard — heart disease, type 2 diabetes, Alzheimer's — are not the norm for them. The term "compression of morbidity" enters the conversation here: while many in industrialized societies experience a prolonged decline in health, hunter-gatherers face a swift, late-stage decline. Their key to delaying morbidity? Lifelong physical engagement.

This principle doesn't just hold on the savannas of Tanzania but also closer to our own backyards. The Stanford Runners Study, spearheaded by medical professor James Fries, casts a revealing light on active aging. The study tracked runners and similarly healthy but sedentary peers over fifty, discovering that mortality rates steadily climbed for non-runners compared to their more agile counterparts. Furthermore, the runners exhibited a slower pace of decline in their day-to-day functional abilities.

Whether you're taking a spirited walk through the Serengeti or jogging through city streets, the message is universal and clear: staying active as the years ascend is not only synonymous with longevity but also the key to warding off age-related diseases and preserving independence.

Hence, regardless of our geographical coordinates, embracing physical activity into our later years could very well be the open secret to a healthier, more vital, and fulfilling lifecycle.

Transforming exercise from a chore to a choice delight

It's set in stone: exercise is beneficial. Yet despite the well-documented perks, many of us treat workout time like a tiresome duty. Why is that? Our evolutionary backdrop provides a clue — voluntary physical activity wasn't a feature of our ancestors' lives, thus modern day exercise can feel unnatural and arduous.

Knowing that we have a biological inclination to dodge unnecesssary physical exertion shouldn't dishearten us but rather fuel our creativity in overcoming this hurdle.

The endgame is clear: To bolster our exercise habits, we must inject elements of necessity and joy into our routines.

Exercise, by nature, isn't usually regarded as essential for survival in today's world, meaning we're less compelled to prioritize it. However, we can craft a sense of urgency around our fitness goals with clever strategizing.

One approach is to involve someone whom you hold in high regard to hold you accountable. Another tactic might be to register for an athletic event and pay in advance — a commitment of funds can be a surprisingly effective motivator. These strategies give our fitness pursuits a taste of necessity, increasing our incentive to stay the course.

Yet, we don't just want to feel obliged to exercise — we want to enjoy it. To turn physical activity from a dreary task into a delightful diversion, we can look to the communal aspect of exercise throughout human history. We, like the hunting and foraging groups of yesteryears, are inherently social creatures. Sharing the exercise experience — be it a partner workout, team sport, or engaging with a personal trainer — can considerably uplift the enjoyment factor.

If social interaction isn't your cup of tea or if you're venturing solo, there are other ways to make exercise pleasurable. The simple act of listening to an engaging podcast or audiobook can transform a mundane workout into an escape you anticipate.

Understanding our natural propensity to seek ease rather than exertion empowers us to adopt smarter, more enjoyable tactics for integrating exercise into our lives. By making workouts necessary, social, and stimulating, we can shift them from the fringe of our daily expectations to a cornerstone of our daily enjoyment.

The essence of integrating exercise into our daily lives

Let's circle back and tie up what we've learned about exercise with a neat bow. The takeaway from this exploration is somewhat paradoxical: while exercise brims with benefits, our innate drive leans towards energy preservation rather than exertion. This inclination might make a regular jog feel less like a joy and more like a job.

But therein lies the challenge and the opportunity. The trick to overcoming our evolutionary energy-saving bias is to craft an exercise regime that appears both indispensable and enjoyable. It's about smartly positioning physical activity not as an option but as a necessity, while also making it a source of pleasure and social connectedness.

Finding the sweet spot also means balancing activity with adequate rest and shunning the temptation to push our bodies into overdrive. Exercising smarter, not necessarily harder, is the mantra for harmonizing our present-day fitness goals with our past survival strategies.

In the end, the goal isn't just to move — it's to move in ways that feel rewarding, sustainable, and intrinsically motivated, reshaping exercise from a modern imposition into an integral, cherished part of our everyday lives.