Book Review: Exercised – Why Something We Never Evolved To Do Is Healthy and Rewarding

I learned of this book from a Twitter account that I follow. The book looks at exercise from the anthropology and biology perspective to answer a few key questions such as:

  • Did we evolve over thousands of years to exercise? Or did we evolve not to spend more energy than we should? Why is exercise such a struggle for many?
  • Why is sitting harmful to our body?
  • How much exercise is enough? What exercise should we do?

The book is jam-packed with research and studies that serve as corroborating evidence of the points that the author tries to make. It must have taken him a long time to dig into hundreds of research like that, including trips to remote places so that he could live with ethnic tribes whose lifestyle is so different from ours dominated by modern technologies. Clearly, the author knows what he is talking about. Even though it’s very research-oriented, the book is well-written and engaging. I do admit that I got tired at times due to its overwhelming length and the number of topics packed in one volume, but for the most part, it was time well spent and an enjoyable read.

The core message of the book is nothing new: Exercise is great for our health and rewarding. But this book offers a little bit more insights into how we can integrate exercise into our daily routine more easily, why certain things happen and how we should design exercise that can benefit us more, especially when we age. I am fairly certain that readers will get away from reading this book with some new knowledge. Below are some of my notes:

“Imagine you have been asked to conduct a scientific study on how much, when, and why “normal” people exercise. Because we tend to think of ourselves and our societies as normal, you’d probably collect data on the exercise habits of people like you and me. This approach is the norm in many fields of inquiry. For example, because most psychologists live and work in the United States and Europe, about 96 percent of the subjects in psychological studies are also from the United States and Europe.

Such a narrow perspective is appropriate if we are interested only in contemporary Westerners, but people in Western industrialized countries aren’t necessarily representative of the other 88 percent of the world’s population. Moreover, today’s world is profoundly different from that of the past, calling into question who among us is “normal” by historical or evolutionary standards. Imagine trying to explain cell phones and Facebook to your great-great-great-grandparents. If we really want to know what ordinary humans do and think about exercise, we need to sample everyday people from a variety of cultures instead of focusing solely on contemporary Americans and Europeans who are, comparatively speaking, WEIRD (Western, Education, Industrialized, Rich, Democratic)

Excerpt From: Lieberman, Daniel. “Exercised : Why Something We Never Evolved to Do Is Healthy and Rewarding

“Which brings us back to physical inactivity. From the perspective of natural selection, when calories are limited, it always makes sense to divert energy from nonessential physical activity toward reproduction or other functions that maximize reproductive success even if these trade-offs lead to ill health and shorter life spans. Stated simply, we evolved to be as inactive as possible. Or to be more precise, our bodies were selected to spend enough but not too much energy on nonreproductive functions including physical activity”

“So let’s banish the myth that resting, relaxing, taking it easy, or whatever you want to call inactivity is an unnatural, indolent absence of physical activity. Let’s also refrain from stigmatizing anyone for being normal by avoiding nonessential exertion. Unfortunately, we have a long way to go. According to a 2016 survey, three out of four Americans think obesity is caused by a lack of willpower to exercise and control appetite.27 Despite stereotypes of non-exercisers as lazy couch potatoes, it is deeply and profoundly normal to avoid unnecessarily wasting energy. Rather than blame and shame each other for taking the escalator, we’d do better to recognize that our tendencies to avoid exertion are ancient instincts that make total sense from an evolutionary perspective.”

Excerpt From: Lieberman, Daniel. “Exercised : Why Something We Never Evolved to Do Is Healthy and Rewarding

“Although most fat is healthy, obesity can turn fat from friend into inflammatory foe. The biggest danger is when fat cells malfunction from overswelling. The body has a finite number of fat cells that expand like balloons. If we store normal amounts of fat, both subcutaneous and organ fat cells stay reasonably sized and harmless. However, when fat cells grow too large, they distend and become dysfunctional like an overinflated garbage bag, attracting white blood cells that trigger inflammation”

“A second way lengthy periods of sitting may incite widespread, low-grade inflammation is by slowing the rate we take up fats and sugars from the bloodstream. When was the last time you had a meal? If it was within the last four or so hours, you are in a postprandial state, which means your body is still digesting that food and transporting its constituent fats and sugars into your blood. Whatever fat and sugar you don’t use now will eventually get stored as fat, but if you are moving, even moderately, your body’s cells burn these fuels more rapidly. Light, intermittent activities such as taking short breaks from sitting and perhaps even the muscular effort it takes to squat or kneel reduce levels of fat and sugar in your blood more than if you sit inertly and passively for long.38 Such modest extra demands appear to be beneficial because although fat and sugar are essential fuels, they trigger inflammation when their concentrations in blood are too high.39 Put simply, regular movement, including getting up every once in a while, helps prevent chronic inflammation by keeping down postprandial levels of fat and sugar.

Excerpt From: Lieberman, Daniel. “Exercised : Why Something We Never Evolved to Do Is Healthy and Rewarding

“These ubiquitous miniature batteries, which power all life on earth, are called ATPs (adenosine triphosphates). As the name implies, each ATP consists of a tiny molecule (an adenosine) attached to three molecules of phosphate (a phosphorus atom surrounded by oxygen atoms). These three phosphates are bound to each other in a chain, one on top of the other, storing energy in the chemical bonds between each phosphate. When the last of these phosphates is broken off using water, the tiny quantity of energy that binds it to the second phosphate is liberated along with one hydrogen ion (H+), leaving behind an ADP (adenosine diphosphate). This liberated energy powers almost everything done by every cell in the body like firing nerves, making proteins, and contracting muscles. And, critically, ATPs are rechargeable. By breaking down chemical bonds in sugar and fat molecules, cells acquire the energy to restore ADPs to ATPs by adding back the lost phosphate. The problem is, however, that regardless of whether we are hyenas or humans, the faster we run, the more our bodies struggle to recharge these ATPs, thus curtailing our speed after a short while.”

“Sugar is synonymous with sweetness, but it’s first and foremost a fuel used to recharge ATPs through a process termed glycolysis (from glyco for “sugar” and lysis for “break down”). During glycolysis, enzymes swiftly snip sugar molecules in half, liberating the energy from those bonds to charge two ATPs. Restoring ATPs from sugar doesn’t require oxygen and is rapid enough to provide almost half the energy used during a thirty-second sprint. In fact, a fit human can store enough sugar to run nearly fifteen miles. But there is a consequential catch: during glycolysis the leftover halves of each sugar, molecules known as pyruvates, accumulate faster than cells can handle. As pyruvates pile up to intolerable levels, enzymes convert each pyruvate into a molecule called lactate along with a hydrogen ion (H+). Although lactate is harmless and eventually used to recharge ATPs, those hydrogen ions make muscle cells increasingly acidic, causing fatigue, pain, and decreased function. Within about thirty seconds, a sprinter’s legs feel as if they are burning. It then takes a lengthy period of time to slowly neutralize the acid and shuttle the surplus lactate into the third, final, but long-term aerobic energy process”

Excerpt From: Lieberman, Daniel. “Exercised : Why Something We Never Evolved to Do Is Healthy and Rewarding

“If you keep up a regimen of two sessions a week of HIIT, your muscles will gradually improve their ability to produce high, rapid forces in part by augmenting how many fibers contract simultaneously when stimulated by nerves. In addition, your muscles will change composition. Although HIIT cannot stimulate your body to produce more fast-twitch muscle fibers, the ones you have will thicken, making you stronger and hence faster. On average, sprinters’ muscles are more than 20 percent thicker than distance runners. HIIT can also modify slower, more fatigue-resistant pink fibers into faster, more fatigable white fibers; lengthen fibers slightly, thus boosting their shortening speed; and increase the percentage of fibers in a muscle that contracts, thereby increasing force. But these and other changes don’t happen on their own, and require constant effort to maintain. If you want to run faster, you have to try to run faster.”

“The benefits of regular HIIT go well beyond its effect on muscles. Among other payoffs, HIIT increases the heart’s ability to pump blood efficiently by making its chambers larger and more elastic. HIIT also augments the number, size, and elasticity of arteries and increases the number of tiny capillaries that infuse muscles. HIIT further improves muscles’ ability to transport glucose from the bloodstream and increases the number of mitochondria within each muscle, thus supplying more energy. These and other adaptations lower blood pressure and help prevent heart disease, diabetes, and more. The more we study the effects of HIIT, the more it appears that HIIT should be part of any fitness regimen, regardless of whether you are an Olympian or an average person struggling to get fit.”

Excerpt From: Lieberman, Daniel. “Exercised : Why Something We Never Evolved to Do Is Healthy and Rewarding

“And therein lies an important lesson about why we exercise. Because exercise by definition isn’t necessary, we mostly do it for emotional or physical rewards, and on that horrid April day in 2018, the only rewards were emotional—all stemming from the event’s social nature. For the last few million years humans rarely engaged in hours of moderate to vigorous exertion alone. When hunter-gatherer women forage, they usually go in groups, gossiping and otherwise enjoying each other’s company as they walk to find food, dig tubers, pick berries, and more. Men often travel in parties of two or more when they hunt or collect honey. Farmers work in teams when they plow, plant, weed, and harvest. So when friends or CrossFitters work out together in the gym, teams play a friendly game of soccer, or several people chat for mile after mile as they walk or run, they are continuing a long tradition of social physical activity.”

Excerpt From: Lieberman, Daniel. “Exercised : Why Something We Never Evolved to Do Is Healthy and Rewarding

“In the end, the 2018 HHS panel concluded that some physical activity is better than none, that more physical activity provides additional health benefits, and that for “substantial health benefits” adults should do at least 150 minutes per week of moderate-intensity or 75 minutes per week of vigorous-intensity aerobic physical activity, or an equivalent combination of the two. (Moderate-intensity aerobic activity is defined as between 50 and 70 percent of your maximum heart rate; vigorous-intensity aerobic activity is 70 to 85 percent of your maximum heart rate.) They also reaffirmed the long-standing recommendation that children need an hour of exercise a day. Finally, they recommended everyone also do some weights twice a week.”

Excerpt From: Lieberman, Daniel. “Exercised : Why Something We Never Evolved to Do Is Healthy and Rewarding

“Aerobic exercise additionally stimulates the growth and upkeep of just about every other system in the body. Within muscles, it increases the number of mitochondria, promotes the growth of muscle fibers, and increases their ability to store carbohydrates and burn fat. In terms of metabolism, it burns harmful organ fat, improves the body’s ability to use sugar, lowers levels of inflammation, and beneficially adjusts the levels of many hormones including estrogen, testosterone, cortisol, and growth hormone. Weight-bearing aerobic activities (alas, not swimming) stimulate bones to grow larger and denser when we are young and to repair themselves as we age, and they strengthen other connective tissues. In moderation, aerobic exercise stimulates the immune system, providing enhanced ability to ward off some infectious diseases. And last but not least, aerobic exercise increases blood flow to the brain and elevates the production of molecules that stimulate brain cell growth, maintenance, and function. A good cardio workout really does improve cognition and mood.”

Excerpt From: Lieberman, Daniel. “Exercised : Why Something We Never Evolved to Do Is Healthy and Rewarding
Physical Activity Guidelines for Americans. Source: HHS

A bit about matcha, how it can benefit your health and why it’s expensive

I have recently taken up a habit of consuming matcha. It is refreshing in this hot weather to drink an iced latte matcha that mixes plant-based milk such as soy or almond milk with the green matcha powder. Apparently, matcha can be pretty good for your health for several reasons, as follows:

Each food has been measured for their antioxidant capacities, in a unit called ORAC (Oxygen Radical Absorbance Capacity). List of ORAC-rich food items – Source: matcha

It can be expensive

There are two main and popular grades of matcha: ceremonial and culinary. Ceremonial grade is the highest grade of matcha that is made of very young tea leaves and requires a lot more care during the process. Hence, it’s quite expensive. Ceremonial grade matcha reportedly has a delicate flavor and should be used in tea ceremonies only. On the other hand, culinary grade match is cheaper because it reportedly is made of tea leaves that are young, yet older than those used to make ceremonial grade. Culinary grade can be used in baking, cooking and beverages.

To get a sense of how expensive matcha can be, take a look at the listings on Amazon for “matcha green tea powder” keyword

Source: Amazon

I buy my matcha from a local shop called The Tea Smith in Omaha. One ounce of culinary grade matcha from The Tea Smith costs $4.5. There is a cheaper alternative that costs only $2.5 per ounce. It is cheaper because it mixes matcha powder with sugar cane. It baffled me as to why matcha is expensive. I did a little research and apparently, the process of producing matcha is quite laborious and unique. Tea leaves have to be shaded from sunlight a couple of weeks at least before they are picked. After they are picked, they go through several steps of steaming, air-drying and removing stems & old leave parts. In the end, there are only soft particles left, which weighs about 1/10 of the original leaves. The particles are then stone-grounded, using uniquely crafted and carefully maintained stone mills. Each mill produces only one ounce or 30-40 gram of matcha per hour.

There is also a Chasen

A Chasen is a whisk specially used to mix matcha powder with water. I bought my whisk for $18.5! I was shocked at the price at first, but would soon understand the reason why after I learned how Chasens are made. Watch the videos below to know how they are created. Trust me, you’ll be blown away by the craftsmanship, patience and incredible talent of the Japanese

This video touches a little bit more on the hachiku bamboos used in the matcha whisks.

In sum, even though regular consumption of matcha can cost a bit, I do think I will continue with this habit in the future, unless there are scientific studies proving that matcha is hazardous to humans. I think given that matcha is linked with a lot of health benefits, it’s a cheap investment into the most valuable asset one can have. Also, as I learned about the art of producing matcha and Chasen, my already big admiration and respect for the Japanese craftsmanship and culture only grew bigger.

Let me know what you think about matcha. Stay safe and have a nice weekend!

Weekly readings – 26th October 2019

AWS Customers Rack Up Hefty Bills for Moving Data. Cloud spending isn’t as cheap as some may think.

The Heart of a Swimmer vs. the Heart of a Runner

Source: DuckDuckGo

Craftmanship in 1930 Vietnam as Seen in Paris Specialized Municipal Libraries. If you want to see a little bit of how Vietnam looked almost 100 years ago, here is a great article

Jeff Bezos’s Master Plan

Is Amazon Unstoppable?

News tab on Facebook

A great post with usrprising details on the spectacular fall of WeWork

Weekly readings – 19th October 2019

Amazon published their official position on a few social issues

Global electric car sales and market share, 2013-18

Source: IEA

The poor in America pay a higher tax rate than the rich. I guess the tax cut is doing what it is supposed to? (I am being sarcastic)

TurboTax’s decade-long war to prevent Americans from filing taxes online for free. I was angry when I read this article. Billions of hours and dollars are wasted every year on filing taxes and only a handful of people benefit at the expense of millions

To buy a phone in China, a face scan will be required as of 1st December 2019

Bob Iger’s massive bet on Disney’s future.

Sleep Deprivation Shuts Down Production of Essential Brain Proteins. The sleep deprivation pandemic is real in our society and there doesn’t seem to be signs of its abating.

How Amazon is redefining the expensive and wasteful process of returns

Boeing lead pilot warned about flight-control system tied to 737 Max crashes, then told regulators to delete it from manuals. Frankly, this is just disgusting. Boeing is one of the two plane manufacturers that dominate the sky and it still has this kind of behavior

America consumes the most sugar per capita

Among what I have to be conscious of while living in the US is not to be drawn into the excessive sugar consumption here. Food & drinks are a bit too unhealthily sweet for my taste and it’s not really uncommon to find items whose more than 50% of their weight are sugar. It’s not that different from pour sugar straight into your mouth!

According to WHO, the recommended daily amount of sugar for consumption is about 11 grams and the figure shouldn’t exceed 25 grams. Below is the list of the top 10 countries where citizens consume the most sugar

Source: World Atlas

Americans on average consume more than 10 times the absolute recommended limit! I have seen folks get sweet spice pumpkin latte instead of black coffee at Starbucks, a boba tea with 70-100% sweetness instead of none, a normal coke instead of a diet one or a big haul of pop corns instead of just drinking water at a cinema. Even though I am aware that sugary items bring instant gratification, we should stay away from them so that we can live a longer and more healthy life, given the dramatic risks that a heavy sugar diet comes with.

Around 3:22 of this clip will you see the harms sugar brings to our health, including brain damage

Almond Milk or Soy Milk

Looking for a tasty and nutritious drink besides cow’s milk and store-bought juice. 90% of which is made from concentrate, I decided to do some research on almond milk and soy milk to see which one is the better choice.

One of the benefits of these two choices is that they are great for those who want to lose weight. Both almond and soy milk contain little saturated fat, sugar or calories.

Source: Healthline

Unfortunately, neither of them naturally contain much calcium, though store-bought milk can be calcium-fortified.

Compared to almond milk, soy milk is richer in nutrition, especially protein (the stereotype that almond milk is a good source of protein is false) and more environmentally friendly as soy requires less water than almond.

Soy milk is allegedly related to weakened fertility in men. A Harvard study in 2009 reported that soy milk consumption might have detrimental effects on male fertility.

The soy study was part of a long-term investigation of environmental factors and fertility. The subjects were 99 male partners of sub-fertile couples. Each man had a medical evaluation and complete semen analysis, and each provided a detailed three-month dietary history that evaluated 15 soy-based foods, ranging from tofu and tempeh to soy milk, veggie burgers, and “energy bars” containing soy protein.

The study found that the men who consumed the most soy had the lowest sperm counts. And it didn’t take much soy to do the trick — as little as one portion every other day was linked to a reduction in sperm count. All in all, the men who ate the most soy had counts that averaged 41 million fewer sperm per cubic milliliter than men who ate the least. The impact was greatest in overweight men, and the results remained valid after age, smoking, alcohol, caffeine, body mass index, and the time between specimen collection and the preceding ejaculation were taken into account.

Harvard Medical School

However, the view was challenged by a study by Harvard School of Public Health in 2015 and another study in 2010. A definite conclusion on the matter remains to be determined. Given all the factors above, soy milk looks to be the winner in this contest.

A podcast on the importance of sleep

I wrote about the book: Why We Sleep before. If you are interested in the subject, yet don’t find the time or the motivation to dive into the pages, you can get the gist of the book at the podcast series here. If you care about your health and brain, I urge you to have a listen.

One of the things I would like to call out here is the unhealthy practice of boasting how little sleep one has in public. Some folks tend to take their deprivation of sleep as a badge of honor. I used to be the same. There was a time before I graduated when I lived on coffee and sweet, to keep myself awake. And I talked about that to my friends with a little bit of pride. However, I learned that it was stupid of me. I was killing my brain and myself. The author is right in calling BS on the “sleep is for the weak. You can have all the sleep after you die” notion.

One of my goals in 2019 is to form the habit of sleeping 7-8 hours a night. Admittedly, I have failed spectacularly so far in the year. There is a lot of work to do…

Most important book I read in 2018

2018 has been a good year in terms of great books. Great reads so far this year include Sapiens, Messy Middle, The Courage to be disliked, Subscribed, to name a few. I wrote quickly about some of them on this blog. However, none is more important than Why we sleep.

Here are a few things I learned:

Sleep isn’t like money in the bank. If you over-spend this month, saving up a little more next month will make up the difference. If you lose one quality sleep one night, that ship has already sailed. There is no getting it back. Hence, the notion of staying up late on the weekdays just to make it up on the weekends is false

Without sufficient sleep, amyloid plaques (poisonous to neurons, killing the surrounding brain cells and associated with Alzheimer’s disease) build up in the brain, especially in deep-sleep-generating regions, attacking and degrading them. The loss of deep NREM sleep caused by this assault therefore lessens the ability to remove amyloid from the brain at night, resulting in greater amyloid deposition. More amyloid, less deep sleep, less deep sleep, more amyloid, and so on and so forth

At fault were the two characters, leptin and ghrelin. Inadequate sleep decreased concentrations of the satiety-signaling hormone leptin and increased levels of the hunger-instigating hormone ghrelin. It was a classic case of physiological double jeopardy: participants were being punished twice for the same offense of short sleeping: once by having the “I’m full” signal removed from their system and once by gaining the “I’m still hungry” feeling being amplified. As a result, participants just didn’t feel satisfied by food when they were short sleeping.

When given just five and a half hours of sleep opportunity, more than 70% of the pounds lost came from lean body mass – muscle, not fat. Switch to the group offered eight and a half hours’ time in bed each night and a far more desirable outcome was observed, with well over 50% of weight loss coming from fat while preserving muscle

With a genuine lack of malice, I proceed to inform them that men who report sleeping too little or having poor-quality sleep have a 29% lower sperm count than those obtaining a full and restful night of sleep, and the sperm themselves have more deformities.

Routinely sleeping less than 6 hours a nigh results in a 20% drop in follicular-releasing hormone in women – a critical female reproductive element that peaks just prior to ovulation and is necessary for conception.

One such foreign entity that natural killer cells will target are malignant (cancerous) tumor cells. Natural killer cells will effectively punch a hole in the outer space of these cancerous cells and inject a protein that can destroy the malignancy.

Examining a healthy young men, Irwin demonstrated that a single night of four hours of sleep – such as going to bed at 3AM and waking up at 7AM – swept away 70% of the natural killer cells circulating in the immune system, relative to a full 8-hour night of sleep.

A large European study of almost 25,000 individuals demonstrated that sleeping 6 hours or less was associated with a 40% increased risk of developing cancer.

A chemical called melatonin helps regulate the timing of when sleep occurs. It governs when the race (sleep) begins, but does not participate in it. Our distractions by modern technology and LED lights suppress and delay the rise of melatonin, meaning that our body is told that sleep should start late. Throw in the enforced awakening by virtue of the industrial culture (alarm clock) and we have a recipe for inadequate sleep.

Memories remain perilously vulnerable to any disruption of sleep (including that from alcohol) even up to three nights of learning, despite two full nights of natural sleep prior.

Selectively warming the feet and hands by just a small amount (0.5 Celsius degrees) caused a local swell of blood to these regions, thereby charming heat out of the body’s core, where it had been trapped. The result of all this ingenuity: sleep took hold of the participants in a significantly shorter time, allowing them to fall asleep 20% faster than was usual, even though these were already young, healthy and fast-sleeping individuals

Most controversial and alarming are those highlighted by Dr Daniel Kripke, a physician at the University of California, San Diego. Kripke discovered that individuals using prescription sleep medications are significantly more likely to die and to develop cancer than those who do not

Saying that alcohol is a sedative often confuses people, as alcohol in moderate doses helps individuals liven up and become more social. How can a sedative enliven you? The answer comes down to the fact that your increased sociability is caused by sedation of one part of the brain, the prefrontal cortex, early in the timeline of alcohol’s creeping effects. As we have discussed, this frontal lobe region of the human brain helps control our impulses and restrains our behavior. Alcohol immobilizes that part of our brain first. As a result, we “loosen up”, becoming less controlled and more extroverted.

Your desire and ability to remain conscious are decreasing and you can let go of consciousness more easily. I am very deliberately avoiding the term “sleep”, however, because sedation is not sleep. Alcohol sedates you out of wakefulness, but it does not induce natural sleep.

Reflection

I have mixed feelings from reading this book. On one hand, I am glad to be enlightened by all the scientific findings on sleep. On the other, I am a bit horrified by what I have done to my body. Nonetheless, I am determined to prioritize sleep more in 2019 and beyond or at least to limit the hard done to my body.

Above are just a few of many great insights that the book offers. I am not doing the book justice, but I hope you spend some time reading this book and gifting it to friends or beloved ones. (I have no connection whatsoever with the author or the publisher. Just a big fan who wants as many to learn about the science of sleep as possible)