Exercise (or simple movement built into a day) was a crucial part of the human environment during human evolution. When we evolved, we walked on our feet, hunted game and gathered berries, brought water from the stream, built our homes by hand, and herded our flocks. All of this involved moving. The homeostatic balances that control human health were all set during a period when humans moved all of the time. Cars and elevators and electric can openers and all the other modern conveniences which reduce the use of our bodies had not yet been invented. It is foolish to think that we humans can simply eliminate movement from our lives without consequence, when it was a crucial assumption present when we were evolving to be who we are. For humans to be healthy, for our homeostatic balance to remain set properly, we need to move, a lot.
Exercise and Stress
Exercise is particularly important related to the human stress response. The stress response is all about preparing your body for an explosive burst of energy consumption right now. In historic times, the stress response was most often triggered by the threat of a predator. Today, we lack predators for the most part, but we have found many situations, mostly psychological like a screaming boss or a violent movie, that induce the stress response. However, these situations typically don’t result in intense physical exertion, the so-called fight or flight response, which was the normal human response to a predator in pre-modern times. This means that the normal response to a stressor which helps the body recover from exposure to the stressor, intense movement, is lacking in westernized societies. And, the stressors that are perceived by the brain to be threats have only increased in frequency and intensity.
This state of affairs is setting humans up for biological disaster, unless an active coping strategy can be invented to substitute. In many western countries, programmed exercise has become the modern human substitute for running like hell from a cheetah. Sports, jogging, aerobics, swimming and all the other forms of exercise we have developed are the primary coping strategy that keeps the wheels from coming off for individuals in our modern world. However, fewer and fewer people are taking advantage of this path to neural salvation, allowing themselves to be distracted from their responsibility to protect themselves from the toxicity of our modern world.
Exercise and Health
Exercise makes the body more resilient in the face of stress. It bleeds off dangerous stress chemicals and hormones. It keeps the body from becoming fat, and fat in excess is very detrimental to the human body, particularly because the adipose tissue highly present in abdominal fat causes a constant, low grade inflammatory response to exist. Exercise improves cardiovascular tone and function. It improves mental clarity and cognition. It reduces the sympathetic activation that occurs during the human stress response. It imposes a balance on cortisol levels. And, it performs many other vital functions that the body needs. Without exercise and movement, humans start a long path towards decline and disease. It is a variant of a pattern present in many animals. For instance, with horses, if they cannot move during a time of stress, they quickly keel over and die. They have to move in order to stay alive. This relationship is not quite as direct and quick in humans, but we, like horses, tend to die early if we do not exercise, and we don’t function very well when we are alive.
A recent study involved numerous people at risk for Type II diabetes. Participants were put on an intensive lifestyle intervention that involved following a low fat diet and walking half an hour five times per week. The results were nothing short of astonishing. Participants in the study reduced their risk of diabetes by 58 percent, whereas participants in another group who took the medication metformin reduced their risk by 31 percent.
People who exercise regularly are less likely to get sick after stressful situations than people who don't exercise. Doctors know exposure to mental or physical stress can increase susceptibility to and severity of disease. In one study, rats that began running on a wheel for four weeks prior to exposure to stress were protected against the suppressive effect of stress exposure on immune response. But rats that either began running on the day of stress or that remained sedentary suffered the negative effects of stress exposure.
New research is showing that exercise beneficially affects your genes, helps reverse the aging process at a cellular level, gives you more energy, makes you smarter, and may even help you grow so many new brain cells (a process called neurogenesis) that your brain actually gets bigger. A study published last year by researchers at the University of Illinois reported that just walking for three hours per week for only three months caused so many new neurons to grow that it actually increased the size of people’s brains.
Regular, moderate exercise also reduces inflammation throughout your body, including in your brain, and reduces the incidence of tiny strokes that can impair your ability to think clearly. Exercise also helps boost your sense of well-being. Levels of beneficial neurotransmitters such as dopamine, serotonin and noradrenaline are higher in those who exercise - the same ones elevated by many antidepressants. These, in turn, may help reduce depression, elevate mood and help you focus better.
In fact, exercise makes you more intelligent. Older adults who exercise regularly have better memory, are better at going from one mental task to another, and can focus and concentrate better than those who are sedentary. In other words, exercise makes older people more intelligent. Exercise makes younger people smarter too. Kids who exercise have fewer problems with attention-deficit disorder and learn faster. Studies have shown that physical education in schools improves academic performance as well as physical fitness. For example, a study by the California Department of Education of 322,000 seventh-grade students found that the most fit scored in the 66th percentile on their SATs, whereas the least fit scored in the 28th percentile.
Exercise and Autism
Probably the most important coping strategy that any autistic child can use to deal with stress is exercise, activity and movement. Research has shown that vigorous aerobic exercise reduced maladaptive and stereotypic behavior in autistic children. Many autistic parents report that their autistic child is much more communicative and calm when they are taking a walk together. This makes all of the sense in the world. The movement is reducing the negative effects of stress response activation, allowing for their brains to operate more effectively and normal motivation programs of desiring to interact to take over from their normal overwhelming desire to withdraw. Personally, I know intimately the benefits of exercise on my mood and thinking. The most effective thinking I ever do is on my bike, riding a familiar route, when I can just let my brain go on sorting through a problem. With my legs churning away, bleeding off my daily stress, the effectiveness of my brain in dramatically enhanced, almost certainly because neural excitation is normalized into an optimal range.
Children with ADHD know the benefits of exercise and movement instinctually; they are not sufficiently troubled to have lost this hard wired coping strategy. They are often described as ‘driven by a motor’, which is how they look as they use constant movement as a way of bleeding off stress. Autistic children need to be encouraged to move in ways other than rocking and flapping. They need to walk, run, crawl, roll, jump, spin circles and do all the other movements that normal children do. Talking and singing are also type of exercise that probably can also help. Chewing is also potentially helpful. Heavy work to the jaw from chomping and biting is energizing.