In today’s media-rich society, the benefits of exercise are advertised around every corner. Most messages seem to promote weight loss and ideal body image as the primary health benefits of exercise. However, abundant research shows that exercise has a positive influence on much more than just the numbers on a scale or waist size, confirming what most people know from personal experience. From the brain and digestive system to mood and sleep habits, physical activity, and exercise have an impact on nearly every part of the body, internally and externally.
Anthropologists hypothesize that the human body evolved in an environment where a tremendous amount of physical activity was required to find food, fight predators, and flee to safety. For most of human history, physical activity has been an integral part of life. Though humans are still built to engage in high levels of physical activity, automation and technology have freed many from the heavy physical labor that was characteristic of previous generations. Although much of humanity no longer lives in the same conditions as our ancestors, our bodies have not changed significantly and still respond to the environment in ways that are very likely similar to the responses of our distant ancestors. Like our ancestors, we still require physical activity for optimal body function and health.
In industrial and post-industrial societies, movement and exercise have become activities that are often separated from daily life, taking the form of sport or leisure activities. Though decades of research show that certain kinds of physical activity and exercise can be an excellent preventative measure and the best prescription for healing the body of ailments and problems that emerge with age, people in many Western countries, like the United States, have become increasingly sedentary. People from cultures where physical activity is intensive and integrated into everyday life do not exhibit the same health problems as people in contemporary industrial and post-industrial societies.
Public health concerns over lack of physical activity among Americans increased in the 1990s, as trends for overweight rose and many chronic health conditions related to sedentary lifestyles worsened. To address these concerns, public health experts conducted an extensive review of scientific research related to exercise and released a reporting important findings:
- The more time one spends exercising and burning calories, the lower the risk of cardiovascular disease incidence and mortality
- Regular moderate physical activity provides substantial health benefits
- Exercising 30 minutes or more on most days provides beneficial health and fitness effects
- In the U.S. as many as 400,000 deaths per year (approximately 17 percent of the total number of deaths in the U.S.) can be attributed to a lack of regular physical activity and to poor diet, so exercise is clearly important. Studies consistently support the numerous health benefits of exercise, including decreased risk factors for coronary heart disease and improved resting blood pressure, glucose tolerance, bone density, immune function, and psychological function, to name a few.
According to a 2007 national phone survey conducted by the Centers for Disease Control and Prevention and state health departments, only 49 percent of Americans got the recommended** daily amount of exercise: 30 minutes of moderate-intensity activity five days per week or 20 minutes of vigorous-intensity activity at least three days per week, or both. The other 51 percent of those surveyed either exercised too little (38 percent) or did not exercise at all (14 percent). The survey also indicated that age (the older one becomes) and education level (the less educated one is) can have a negative influence on exercise habits.
A commonly-cited barrier to exercise is lack of time. Fortunately for people pressed for time, there is good news from some recent studies on high-intensity interval training, or HIT. According to the studies, HIT appears to be an efficient alternative to moderate long-term exercise. A 2007 study from Denmark and a 2010 study from Canada have shown that vigorous exercise over short periods of time can be as effective or more effective than moderate-intensity exercise over a longer period of time. The Canadian study showed that even exercise of less intensity than an all-out sprint can still be effective, suggesting that HIT is accessible to many different types of people. These findings reflect the reality that some exercises are more effective than others.
The scientific materialist approach to exercise and its effect are not the only approach. Other paradigms recognize models of the body that include dimensions that biomedicine and Western philosophy do not generally address. These dimensions are usually characterized by describing or working with energy, also known as life-force, chi or prana. In traditional Asian medicine paradigms (Traditional Chinese Medicine and Ayurveda) circulation, which includes fluids, blood, and energy, is considered primary for sustaining all bodily functions. The better the circulation, the better the body will function and feel. The more energy available, the healthier the body will be. For these health-medical systems one of the principle causes of most bodily dysfunctions and health problems can be traced to a lack of circulation and energy conductivity or an imbalance in circulation. Ill health can be caused by either congested energy or lack of energy. In this view, diet and certain types of physical activity have the greatest effects on circulation and therefore health.
Exercise is often separated into a number of different categories, though these categories are not entirely independent and the many types of exercise influence one other. “Exercise” can be divided into those which focus on gross body and directly address muscles, skeletal systems, and internal organ systems (e.g., jogging, weight lifting, swimming, etc.), and those that focus on subtle-energetic body (e.g., Tai Chi and Qi Gong), which can also effect internal organs and the musculoskeletal system. The distinction between these two types of exercise is not clear-cut, because in actuality they are interdependent. But the focus, practices and results can be very different.
The two most important forms of physically oriented exercise are aerobic exercise and anaerobic exercise. Aerobic exercise includes any type of exercise that raises and then maintains an increased heart rate, during which oxygen is used by the muscles to burn fats and glucose and produce energy. Aerobic exercise, such as running, is usually performed at moderate levels of intensity for extended periods of time so that muscles require oxygen to maintain the activity. In anaerobic exercise the muscles do not require oxygen and instead rely on glycogen, or stored blood sugar, for energy. Anaerobic exercise, such as weight lifting, is usually of moderate or high intensity but is maintained for short periods of time. Anaerobic exercise and aerobic exercises generally occur simultaneously because anaerobic metabolism must often supplement the aerobic system. What is generally called aerobic exercise might be better termed “solely aerobic” exercise.
Physical-energetic forms of exercise focus on the energetic (subtle) level rather than on the gross physical body. Qi Gong and Tai Chi work with both the physical and energetic body and relate the body, mind, energy, and breath through patterns of sequenced movements. Exercises like Qi Gong and Tai Chi are very low impact and promote flexibility, balance, strength and relaxation, improve circulation, lower blood pressure, and increase energy. For some people these exercises may be more appropriate, depending on health goals and physical condition. Ideally, it is best to combine different types of exercises.
It is important to note that each person has a different physical and energetic system and may require a different type of exercise. For example, people who have been sedentary will not be able to leap into a vigorous exercise routine and will have to gradually ramp up to their full potential. Older people may require exercise that is low-impact and that emphasizes flow rather than strength. Each body has different abilities, and each person has a different personality. It is important to tailor any exercise regimen to the body type and personality of the person doing the activity so that it can be maintained over time. More is not always better, and it is essential to take individual circumstances and health conditions into account. Ideally, people should consult professionals before beginning any new exercise program.
IMPROVES HEART HEALTH, DISEASE PREVENTION
There has been a fair amount of research on the link between physical activity and heart health. A 2003 statement by health experts in the U.S. Council on Clinical Cardiology and the Council on Nutrition, Physical Activity and Metabolism strongly supported findings that routine (aerobic) physical activity prevents the development of coronary artery disease and even reduces symptoms in patients already diagnosed with cardiovascular disease. Inactivity is one of five major risk factors (along with high blood pressure, abnormal values for blood lipids, smoking, and obesity) for cardiovascular disease. Inactivity can increase one’s risk of experiencing a cardiac event 50 times compared to the risk of those who exercise five times per week. The statement also reported evidence that exercise reduces the risk of other chronic diseases such as Type 2 diabetes, osteoporosis, depression, and cancer of the breast and colon.
In a 2011 study researchers analyzed the health benefits of weight training versus aerobic exercise and concluded that a combination of the two is optimal for heart and overall health. Participants who engaged in only aerobic exercise lost an average of three pounds and saw a decrease in blood pressure, triglyceride levels and “metabolic syndrome” scores, which reflect combined heart and diabetes risk factors. However, they did not gain much strength. Participants who did only weight lifting, on the other hand, gained strength but did not see many heart health benefits or decreases in diabetes risk factors. Those who engaged in both forms of exercise experienced four pounds of weight loss and all the heart health benefits.
Exercise has long been linked with reduced rates of breast and colon cancers and studies are now exploring why. A recent ABC news report listed several recent discoveries from two studies, both from 2011. First, fat cells in the body create more insulin and estrogen, both of which aid the growth of cancer cells. Exercise actually changes the composition of the body’s cells. It also helps reduce stress and inflammation, both of which have been linked to the growth of cancer cells. One study of 4,000 women with breast cancer found that those who reported the highest level of physical activity had half the risk of dying compared to breast cancer patients who did not exercise. Another study found that women who walked 3-5 hours a week at an average pace saw the greatest benefits in terms of breast cancer. As one doctor explained, bodies are programmed to find and expel the dangerous cells that tend to circulate; exercise might be one of the ways the body does this.
The effects of an exercise program on any single risk factor may generally be small, but the effect of routine, moderate exercise on overall health and cardiovascular risk, when combined with other lifestyle changes (proper nutrition, smoking cessation and medication use when necessary) can be dramatic.
Exercise maximizes oxygen flow in the body and improves cholesterol and triglyceride levels. No matter your weight, being active boosts high-density lipoprotein (HDL), or good cholesterol, reduces low-density lipoprotein (LDL), or bad cholesterol, and decreases triglycerides, a form of fat that circulates in the blood and is stored in fat cells. These improvements keep the circulatory system functioning smoothly, decreasing a number of other health risks such as cardiovascular disease, stroke, type 2 diabetes and metabolic syndrome. In diabetic patients in particular, exercise can favorably affect the body’s ability to use insulin to control glucose levels in the blood.
Several papers presented at the 2011 American Institute for Cancer Research conference emphasize the relationship between sedentary lifestyles, exercise, inflammation, and cancer. One study found that sedentary lifestyles increase the amount of inflammation in the body, in turn increasing one’s risk for cancer. Researchers found that even people who exercise regularly but otherwise experience a sedentary lifestyle may be at an increased risk of inflammation and cancer.
Another paper at the conference concluded that nearly 100,000 cases of breast and colon cancer each year could be linked to a lack of physical activity. Researchers recommend that people break every hour of sitting with several minutes of activity.
THE BENEFITS OF OTHER FORMS, ANCIENT AND MODERN
Although numerous people use jogging and weight lifting as their main types of exercise, other activities such as swimming hold various health benefits. Swimming, for instance, is both low-intensity and works nearly every muscle in the body as well as the cardiovascular system. Bicycling is also a wonderful low-impact exercise. Here are a few very important yet overlooked exercises.
The ancient system of Yoga, which is a part of Ayurveda growing in popularity, is very effective for overall health and well-being. Yoga has been shown to be one of the most effective types of activity for treating back pain. Asana Yoga, commonly referred to as Hatha Yoga, is a low-impact, anaerobic yet very powerful form of exercise. Yoga exercises provide variations on stretching. The exercises work to contract and relax muscles and organs, benefiting the whole body. Specific exercises (known as Asana) affect particular organs and regions of the body. For example, exercises such as Uddiyana Bandha, an abdominal lock, and Bhujangasana, the cobra pose, can affect the abdominal region and the digestive system. Other Yoga poses include Salamba Sirasana (head stand) and/or Adho Mocha Vrksasana (hand stand). These poses greatly increase blood flow and oxygen to the brain and aid cardiovascular function and overall circulation, including the lymphatic system, which is essential to the immune function.
For most people, learning Yoga poses will require some instruction, but the benefits far outweigh any perceived inconveniences. For instance, Yoga helps reduce stress and anxiety, improve sleep, and increase elasticity, blood circulation, endurance, concentration, physical strength, and structural balance. Yoga can also help with conditions such as asthma, fibromyalgia, and hypertension, as well as back pain. Pranayama Yoga exercises can quickly balance the sympathetic and parasympathetic nervous system, helping balance and homeostasis for the whole body.
Significant research—for example, by Loren Fishman, a specialist in physical and rehabilitative medicine affiliated with New York-Presbyterian/Columbia hospital—shows that Yoga poses, in combination with some physical therapy, can, in an overwhelming number of cases, relieve pain associated with orthopedic disorders. For instance, one study using participants with osteoporosis and with its precursor, osteopenia, found that those who did 10 minutes of Yoga daily for two years increased bone density in their hips and spines while the bone density of those who did not engage in Yoga tended to decrease or remain static (Fishman, 2009). Thus, patients with osteoporosis and/or who must undergo surgery should try Yoga first, since it is a less invasive, much less expensive treatment that has yielded significant positive results.
Studies have demonstrated that older people who practice Tai Chi show improvements in balance, flexibility, muscle strength and cardiovascular function. A study of men aged 65 and older showed that men who had been practicing Tai Chi for at least 10 years showed better balance, flexibility, and cardiovascular function than a sedentary group. Significantly, the group who practiced Tai Chi did not participate in any other fitness programs on a regular basis. Another study found that a moderate Tai Chi practice can enhance confidence, quality of life, and functional mobility in older adults with osteoarthritis. There is evidence from other studies that Tai Chi has positive effects on the immune system, aerobic capacity, and bone density.
Tai Chi has been shown to be particularly useful for preventing falls in older people. Up to 50 percent of people 65 years and older are at risk for falling annually, and falls are the most common type of accident in this age group (Zeeuwe et al., 2006). While the number of falls was not greatly reduced in every study, elderly people who practiced Tai Chi in several studies generally reported a reduced fear of falling and a greater confidence in their physical abilities.
Inverting the body has some unique effects on the body that other exercises do not have. It is not a substitute for aerobic exercises but should be considered separately. Inversion exercises include Yoga poses like headstands and handstands, or using an inversion table or stand. Many people cannot do a headstand, but people can purchase inversion tables, which are very easy to use and require almost no physical effort. The Yoga poses are more active and the inversion table is more passive. It is possible for many different types of people to use the inversion table. Inversion is an extremely efficient form of exercise. It is good for relaxing all muscles groups, countering the effects of gravity and lengthening the spine to prevent back pain and to promote good posture. The inversion table can be used simultaneously to add core (back and abdominal) strengthening exercise like sit-ups as well.
Rebounding, a set of exercises on a mini-trampoline, is another equipment-aided form of exercise with unique benefits and advantages. No other form of exercise utilizes gravity to such a great advantage as rebounding. Rebounding is particularly beneficial because the effects of increasing and decreasing gravity while jumping helps strengthen every type of cell in the body, not just muscle cells. One of the keys to maintaining health is for the body to release toxicity. Rebounding helps flush the body of toxins. (Remember to always drink a lot of water after all exercising.) It also activates the lymphatic system, helping to flush metabolic waste and keep the cellular environment saturated with oxygen, nutrients and enzymes.
By simply jumping up and down, the positive effects take place. You can also add aerobic exercises while using the trampoline through gentle jogging, choreographed routines, and jumping with small weights. One study of rebounding found that its aerobic effect was comparable to jogging on a treadmill. Up to 80 percent of injuries related to aerobic exercise are caused by overuse associated with repetitive impact. The rebounder absorbs and decreases the amount of impact sustained by the joints, so the use of rebounding may reduce injuries related to jogging and other forms of aerobic exercise, such as shin splints and tendonitis. Rebounding may be especially useful for people with joint problems or who need to avoid high-impact activities. Not all mini-trampoline are the same so do your research before you purchase one.
EXERCISE IMPROVES DIGESTION
In addition to improving heart health and the body’s blood and oxygen flow, exercise can also improve digestive system function. In fact, there is strong evidence that physical activity reduces the risk of colon cancer by at least 25 percent. One study found that physical activity can improve gastrointestinal (GI) symptoms in people who are obese. Of more than 1,800 participants enrolled in a 24-month randomized trial, those who incorporated some form of exercise into their routine had fewer GI symptoms than others who were inactive—that is, they had fewer stomach pains and instances of constipation, diarrhea, and irritable bowel syndrome.
Other studies have shown that repetitive exercises at relatively low intensity may have protective effects on the GI tract, and may reduce the risk of diverticulitis, gastrointestinal hemorrhage and inflammatory bowel disease. Researchers postulate that decreased GI blood flow, increased movement in the gut, changes in the system that regulates neurological, immune and endocrine responses, and even the bouncing during exercise are behind these effects. It is worth noting that these same studies and others have shown that prolonged intense exercise can have a negative effect on digestion and nutrient absorption and can cause many GI symptoms, with up to half of elite athletes experiencing GI bleeding, heartburn and other symptoms.
POSITIVE IMPACT ON AGING AND BRAIN HEALTH
Exercise can improve blood flow to the brain and heart, decrease muscle decay, produce stronger bones and joints, improve brain activity, increase immune system response, and delay or reduce the risk of developing diabetes and some cancers. Overall, aerobic activities and/or strength training have been shown to help slow the body’s natural aging process by improving and/or maintaining body functions that normally deteriorate with age. While there is no experimental evidence directly linking exercise to the body’s aging process in humans, there is copious anecdotal evidence, and numerous human and animal studies suggest that exercise targets many aspects of brain function and has broad effects on overall brain health, resilience, learning, memory, and depression, particularly in elderly populations.
One study conducted with mice suggests that exercise may reduce the effects of aging. Specifically, physically active mice—who exercised the equivalent of a person running 6.2 miles in 50-55 minutes—were genetically programmed to age more quickly but remained energetic, had dark fur, full muscle mass and retained more brain volume compared to the sedentary mice. Researchers hypothesized the difference lies in exercise’s effect on mitochondrial function.
Over the past decade, magnetic resonance imaging studies have pointed to cardiovascular and aerobic fitness as key components of brain health. Aerobic fitness helps preserve grey matter and tissue density in the brain, which typically decreases with age. Aerobic fitness also affects mitochondrial function, which plays a role in the course of aging and brain volume. This, in turn, delays the onset and decreases the risk of developing Alzheimer’s disease, Huntington’s disease, and Parkinson’s disease. Research also has shown that exercise increases levels of the brain molecule PGC-1 alpha, which may protect against the onset of Alzheimer’s disease. For older populations, studies show that a little bit of exercise every day can go a long way. In a study of 197 participants in their 70s, those who expended the most energy over the two weeks measured had 90 percent lower odds of developing cognitive decline over the five- to seven-year follow-up period.
Exercise fires up growth factor signals that stimulate neuronal plasticity (the brain’s ability to change)—this can enhance cognitive function and stimulate neurogenesis, or the development of nerve tissues. Exercise can also reduce inflammation in the brain, decreasing peripheral risk factors (e.g., diabetes, hypertension, and cardiovascular disease) that lead to cognitive decline and neurodegeneration, most likely through suppressing the growth of pro-inflammatory molecules in the brain while at the same time increasing growth factor levels and signals.
Exercise also triggers the production of endorphins, the body’s own opioids. When one engages in physical activity long enough, the brain’s prefrontal and limbic regions release endorphins. These bind to the brain’s opioid receptors and cause a sensation of happiness, or of being “high.” This endorphin-induced “runner’s high” acts as a painkiller, improves mood, and has been considered for therapeutic uses, especially for anxiety, stress, and depression.
For those already affected by dementia, exercise can help slow the progression of diseases related to dementia. A 2004 meta-analysis of studies analyzing the effects of exercise training on elderly people with cognitive impairment and dementia suggested that walking, dancing, and some weight training (in addition to other low-impact exercises) can improve performance on cognitive tasks. Also, studies suggest that those who engage in long-term, regular exercise three hours or more per week have many more small blood vessels in their brains than those who exercise sparsely, or only one hour or less per week. The increased blood flow to the brain can help those with Alzheimer’s disease keep cognitive function and possibly help delay the onset of Alzheimer’s disease.
Exercise also has the potential to prevent and treat depression. Cognitive decline has been linked to depression and depression is considered a significant global health burden. Numerous human studies have shown the therapeutic effects of exercise on depression in both young and older individuals, with the benefits, linked to hippocampal neurogenesis, comparable to those achieved with anti-depressants. The more one exercises, the greater the depression-related improvements. A recent study, reported on in The New York Times, found that exercise works well in some people for achieving remission from depression that is resistant to treatment with standard anti-depressants. For men, fairly energetic exercise, such as a brisk 30-minute walk every day, and, for women a slightly lighter exercise regimen, in tandem with an SSRI anti-depressant, was effective in achieving remission.
AFFECTS SLEEPING HABITS
For years, researchers and specialists have tried to understand the benefits of sleep for the body. There is a general consensus that sleep (the right type and amount) positively affects brain and body functions. More recently, research has begun analyzing the role exercise plays in sleeping habits, specifically how physical activity can improve sleep quality.
Reaching the dream stage (REM stage) during sleep, for instance, has been shown to be important for the development of the central nervous system (which has an impact on memory formation) and for pain sensitivity (uninterrupted sleep protects against pain, including chronic pain). Getting to the dream stage may be easier after engaging in exercise, since physical activity leads to deeper sleep. Exercise promotes slow-wave sleep, or delta sleep, which helps promote the feeling of being refreshed and rejuvenated and encourages the release of growth hormones. Children with conditions that interrupt slow-wave sleep (e.g., chronic asthma) can experience growth hormone deficiencies.
To help ensure more accurate measures, researchers have begun using athletes as participants. One study that examined the properties of slow-wave sleep in athletes and non-athletes found that, despite being exposed to noise stimuli meant to slightly interrupt sleep, athletes woke up feeling much more refreshed than non-athletes, who felt as though they did not sleep enough, indicating that their slow-wave sleep was not refreshing. Athletes included participants who routinely ran 10,000 meters daily, and non-athletes included non-intense, non-habitual runners. In addition to improving slow-wave sleep, exercise may also have an impact on how quickly one falls asleep. Physical activity increases the core body temperature, and when the body cools down, the decrease in temperature can invite sleep.
The rise of automation has brought with it ease and freedom from physical labor, though it also has produced unexpected side effects—sedentary lifestyles and a population that is disconnecting from everyday physical activity. Integrating activity and exercise into daily life has been shown to be essential to good health. Physical activity is often not naturally integrated into our lives, so it is important to find the most effective exercise for your lifestyle. Experts, researchers and others cannot yet give an absolute answer for which type of exercise is the best for overall health—rigorous high-intensity interval exercises, sustained low-intensity and low impact exercise and vigorous activities of daily living have all proven effective under different circumstances, for different people. There is wide consensus, however, that being physically active, at any age and for all body or somatic types, is greatly beneficial to human health. We also know physical health can be improved through energetic exercises developed in Asia. Physical activity has an effect on every major organ system, and it deeply affects mind, brain, and mood. Both Western biomedicine and Asian medical practices acknowledge the importance of exercise and physical activity. Raising the heart rate for a sustained period of time at least three days a week is ideal, but exercise can be as simple as a brisk walk, a Tai Chi practice, stretching or even vigorous gardening. And now, thanks to modern equipment like the trampoline and inversion table, we are able to utilize gravity in ways we haven’t in the past. For the best results, determine your particular needs and formulate an exercise regimen to follow those needs. Whatever form it takes, it is important to find a way to just get moving every day.
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