If You Don’t Use It, You Lose It
I get bursts of creativity with bursts of physical activity.
Payal Kadakia1
I want you to do an experiment. Use a stopwatch or clock with a second hand, and for just one minute—only sixty seconds—sit perfectly still. Not just quiet, not with minimal movement, but don’t move one muscle in your entire body (other than breathing)—don’t blink, don’t shift, don’t turn your head, don’t swallow. Try it. What happened at the end of that one minute? Did you find you had some urgency to move?
We are designed for movement, for activity, for exercise. Yet our modern world has interfered with healthy exercise. Ancient humans exercised as part of daily life. Survival required exercise—long hunting trips, often walking or running great distances, working long hours in the fields planting and harvesting crops. Just the routines of gathering firewood and water, washing clothes, preparing food (grinding flour, kneading bread, etc.), and even walking outside to the privy required movement. Those who didn’t exercise often didn’t live very long. Almost all of life’s activities required significantly more exertion—exercise—than life requires today. But the benefits of exercise have been known for millennia.
In China around 2500 BCE, it was noted that exercise prevented certain diseases termed “failed organs.” These diseases were perhaps diabetes and heart failure. The writings of Confucius promoted exercise and various gymnastics. Martial arts with daily, regimented routines were introduced and are still practiced by large segments of the Chinese people today. The Chinese also enjoyed other physical activities such as badminton, archery, dancing, and wrestling.
In India, a form of yoga was developed that is the most commonly known form in the West and is a series of various body postures and positions requiring regular physical exertion. It was recognized in ancient India that regular exercise was necessary for optimal health.
Perhaps no ancient society has had greater impact on physical fitness in the West than ancient Greece. The Greeks not only found the human body beautiful and the object of art but also promoted the development of physical fitness. Ancient Greeks developed the Olympics, and some Greek scholars such as Hippocrates and Galen spent their lives studying the human body and promoting physical health. However, much of their influence was lost with the fall of the Roman Empire and the breakdown of organized society.
During the Dark and Middle Ages life consisted of hunting, gathering, maintaining shelter, and tending cattle. Exercise was required if one was to survive. Those not fit enough to engage in the physical rigors of life, unless they were from quite wealthy families, would typically die.
Tribal life in the Americas was similar. Exercise was required for survival. Even those who didn’t hunt and gather would carry heavy loads, tan leathers, set up dwellings, cut wood, and prepare food. Life prior to the modern industrial revolution was a life of nearly constant physical exertion.
The founders of the United States recognized the importance of regular exercise. Benjamin Franklin said, “Use now and then a little Exercise a quarter of an Hour before Meals, as to swing a Weight, or swing your Arms about with a small Weight in each Hand; to leap, or the like, for that stirs the Muscles of the Breast.”2 And Thomas Jefferson is noted for recognizing the value of regular exercise, and not just for the health of the body; he also realized that a healthy body promoted a healthy mind. Following are three of his noteworthy comments:
Exercise and application produce order in our affairs, health of body, cheerfulness of mind, and these make us precious to our friends.3
Walking is the best possible exercise. Habituate yourself to walk very far.4
A strong body makes the mind strong.5
From the founding of the United States in 1776 throughout the nineteenth century, the vast majority of life’s activities required daily physical exercise. The industrial revolution, however, changed life drastically. Modern machinery reduced the amount of physical labor required for almost every task. The cotton gin, steam engines, tractors, automobiles, trains, dishwashers, washing machines, dryers, and vacuum cleaners have reduced the amount of exercise required for vast segments of society.
Indoor plumbing and electricity further reduced physical activity. Elevators reduced stair climbing; cable cars, buses, subways, and automobiles cut down on walking. Manufacturing plants and assembly lines drew people from agricultural life to city living, resulting in standing in place for long hours. And all this modern living has contributed to an epidemic of diseases never before seen in society—diabetes, hypertension, hypercholesterolemia, heart disease, and obesity—all of which accelerate aging and undermine brain health.
Please don’t think I am suggesting humanity was better off before the industrial revolution—not at all. I am only saying that along with many blessings to humanity, the industrial revolution also brought an unforeseen consequence—reduced physical exercise with subsequent worsening health.
The good news is we are still free to exercise. Whereas prior to the industrial revolution exercise was part of daily living, for most of us today we must choose to make exercise part of our lives. If we do, the benefits are enormous.
Benefits of Physical Exercise
Regular resistance and aerobic exercise increase muscle strength, cardiovascular fitness, and bone density.6 And the benefits of exercise are realized at every age. The Fitness Arthritis and Seniors Trial (FAST) demonstrated that older adults who exercise are 40 percent less likely to develop disability than those who do not exercise.7
We not only have fewer disabilities as we age if we exercise, but we also reduce inflammation in the body. Regular aerobic exercise causes the muscles to produce the powerful anti-inflammatory factor interleukin-10.8 This factor suppresses inflammatory cytokines known to contribute to increased risk of depression, dementia, vascular disease, diabetes, obesity, and some chronic-pain conditions.
Regular exercise causes the brain to produce at least three different neurotrophins (brain-derived neurotrophic factor, nerve growth factor, and vascular endothelial growth factor). These proteins cause the brain to make new neurons, stimulate existing neurons to sprout new connections, and provide support in maintaining the health and vitality of our brain cells.9 Older persons who exercised regularly saw 2 percent growth in the hippocampus of their brains. This is the part of the brain in which all new learning takes place. As I mentioned previously, this new growth reversed approximately two years of aging!10 Let me emphasize this last point. Exercise resulted in growth in the part of the brain in which new memories occur, and the new growth was the equivalent to turning the clock back two years! In this study participants started out walking ten minutes per day at a faster pace than their normal walking speed and increased each session by five minutes each week. At the seventh week they were walking forty minutes per day.
Animal studies reveal the same results. Active animals have larger hippocampi, which means they can learn faster than sedentary animals.11 And older people who walk just fifteen minutes per day have a lower risk of Alzheimer’s dementia.12 People who routinely exercise exhibit better cognitive abilities and sharper memory and have larger brains than people who do not routinely exercise.13
Physical exercise provides all the benefits listed above, and the circuits of the brain that initiate movement (striatum) also initiate thinking. This is why persons with Parkinson’s disease, which is caused by the loss of cells in the striatum, have not only slowed physical movement but also more difficulty initiating thoughts.14 And while scientists have known for years that the cerebellum coordinates our physical movements so they are smooth, organized, and balanced, more recent research has documented that the cerebellum also coordinates our thinking.15 This means that physical exercise not only improves brain volume but also enhances the circuits of the brain involved in initiating, organizing, and coordinating our thought processes. This is why sparks of insight often occur when people are exercising. It is also an important reason for children to get regular physical activity; as they exercise they develop the circuits of the brain that not only help motor control but also improve thinking and cognitive control.
Every organ and motor system of the body has as its primary purpose to serve the brain—to provide oxygen, nutrients, and data input to the brain or to move the brain from place to place or to carry out the desires and intentions of the brain. It is no wonder, then, that maintaining a healthy body has such a huge impact on the health of the brain.
Exercise is a requirement for life. It is a design law—a parameter on which life is constructed to operate. If you want something to get stronger, you must exercise it. As we discussed in chapter 2, if you want stronger muscles, you must exercise them. If you want stronger math ability, you must work problems. If you want stronger musical skill, you must practice your instrument. This is the law of exertion—strength comes from exercise. Or as it’s more commonly put: use it or lose it.
Benefits of Mental Exercise
While it is true that we must exercise the body in order to be healthy, to have the healthiest brain possible we must also exercise our minds.
When we choose to practice a musical instrument we direct neural circuits to fire that are associated with that activity. The more we fire them, the more neurotrophins (brain-produced fertilizers for the neurons) are released in those specific circuits and the more neurons and neuron-to-neuron connections are made, thus increasing the complexity of the brain circuitry, which corresponds with increased capacity and efficiency of whatever behavior one is practicing. And sure enough, the brains of musicians have been found to be structurally different from the brains of nonmusicians in areas that correspond to fine motor activity and auditory and visual processing.16 The brain adapts and changes as a result of our choices for every activity of life. To maintain a healthy brain we need to exercise both our bodies and our minds.
We can exercise our minds by reading new material that requires thinking and contemplation and learning new concepts. Write, do puzzles, engage in new physical activities such as art or learning to play an instrument, playing ping-pong, learning to waltz, or learning a new language. Mentally stimulating activities and certain brain-training programs are associated with lower brain amyloid levels (a protein associated with Alzheimer’s) and a decreased risk for AD, as are graduating from college or engaging in lifelong learning.17
Physical Exercise Recommendations
See Your Doctor!
First and foremost, before starting any exercise program see your doctor, get a physical exam, and discuss your plans with your health-care provider. Starting an exercise routine after years of sedentary living can be dangerous and actually cause injury, so it is important to start low and go slow. This means to start with low intensity, low weights, and low repetitions and increase slowly. Overdoing it can cause muscle, bone, joint, and tendon injuries as well as potential life-threatening problems for those with serious cardiovascular disease. Therefore, step one is to see your doctor and together formulate a plan to get you back in top physical shape.
Choose Exercises That You Find Enjoyable
After seeing your doctor, step two is to choose exercises that you find enjoyable, not stressful.
Anecdotal reports have been around for years of individuals who exercise but who don’t experience improvement in metabolic health—they don’t lose weight and they don’t experience improvement in lipids or glucose control. This led health-care providers to doubt their patients who reported they were exercising.
However, in 2012 a study of 1,687 individuals revealed that 10 percent of people who exercised regularly experienced worsening cardiovascular and diabetes risks.18 This may be due to the mindset of the person doing the exercise. When we are stressed the brain activates the amygdala (stress circuit), which in turn activates the hypothalamic-pituitary-adrenal axis, increasing stress hormones. The stress hormones activate the immune system, increasing chemokines, cytokines, and other inflammatory factors. It is well documented that chronic activation of this inflammatory cascade contributes to worsening cardiovascular and metabolic risks, including worsening diabetes and obesity. Therefore, one potential reason that a subset of people who exercise regularly do not experience benefit is that they may be exercising with a mind that is stressed; they may dread or dislike the exercise and thereby worsen the inflammation in their body.
A very simple fix is to choose physical activities that you enjoy. Make the exercise a by-product of the activity, such as playing tennis, racquetball, walking while golfing, hiking, dancing, or rowing while fishing. Another way to make exercise more enjoyable is to make it a part of a group experience—walk together with family or friends or join an exercise class. If none of these work for you, consider exercising while listening to audio books that you look forward to hearing. Doing these things shifts the mind’s focus away from the exercise and onto the game, the friends, the beauty of nature, or the story, which in turn changes the emotional experience from one of stress and dread to one of fun and joy.
Be Balanced!
While it is well documented that too little physical activity undermines health, recent research has demonstrated that too vigorous exercise also undermines health, increasing oxidative stress. Those who engage in extreme exercise routines such as marathon running, iron-man competitions, and the like have the same mortality rates as those who don’t exercise at all.19
Recommendations for optimal exercise include:
LEARNING POINTS
ACTION PLAN: THINGS TO DO