Exercise: The Medicine Since Antiquity

Introduction

The exercise boom is not just a fad; it is a return to ‘natural’ activity—the kind for which our bodies are engineered and which facilitates the proper function of our biochemistry and physiology. Viewed through the perspective of evolutionary time, sedentary existence, possible for great numbers of people only during the last century, represents a transient, unnatural aberration.” (1).

As discussed in my earlier post, ‘Exercise is Medicine: but a grossly underutilised therapy‘, physical activity is one of the most important things you can do for your health. Overwhelming evidence exists that lifelong exercise is associated with numerous health benefits. Regular physical activity helps improve your overall health, fitness, and quality of life. It also helps reduce your risk of lifestyle diseases like type 2 diabetes, cardiovascular diseases (heart disease and stroke), many types of cancer, and chronic respiratory diseases. It also improves mental health (reduces depression, anxiety, and dementia).

Physical inactivity is the biggest public health problem of the 21^st century (2, 3). In this background, in Nov 2007, the American College of Sports Medicine (ACSM) and the American Medical Association (AMA) co-launched Exercise is Medicine: A Global Health Initiative. The aim was to make physical activity assessment and exercise prescription a standard part of the disease prevention and treatment paradigm for all patients. On the face of it, it looks as if exercise’s role in people’s health is a new ‘discovery’. However, the concept that exercise could be considered medicine, or part of medicine, is almost 2.5 millennia old.

Contribution of ancient physicians in promoting exercise for health

Though in most writings on the role of exercise in health and disease, authors begin with the two most prominent physicians of the ancient world – Hippocrates and Claudius Galenus, or Galen. However, this is an obsession of Western historians of medicine that needs correction. There is enough evidence of physicians from India’s ancient civilisation recognising the role of exercise in health and disease more than a century before Hippocrates.

Contribution of physicians from the ancient Indian civilisation

India was one of the great seats of an ancient civilisation. The two most prominent physicians from ancient India who richly contributed to exercise physiology are Sushruta (600 BC) and Charaka (250 – 100 BC).

Sushruta

Sushruta (also spelt as Susruta) was a physician in ancient India who taught surgery and medicine at a university in the ancient Indian city of Kashi, popularly known as Benares, around 600 BC (4). The most authentic compilation of his teachings and work is presently available in a treatise called “Sushruta Samhita”. From a historical perspective, Tipton from the Department of Physiology, University of Arizona, based on an extensive review of literature, highlighted the vast contribution of Sushruta to exercise physiology and how this information has been omitted by most authors while considering the history of Exercise Physiology (5).

Sushruta was the first “recorded” physician to prescribe moderate daily exercise for his patients for health reasons (5). Sushruta believed that medical practice should lay equal emphasis on the prevention of disease as well as curative remedial procedures. He believed that a sedentary lifestyle that involved physical inactivity and sleeping through the day, along with excessive food and fluid consumption, would sufficiently elevate the Kapha humor to a level that could disrupt the humoral equilibrium leading to a disease state and potential death. He felt regular moderate exercise provided resistance to disease(s) and “against physical decay” and stated, “Diseases fly from the presence of a person, habituated to regular physical exercise…” (5, 6). Interestingly, Sushruta even talks about diabetes and obesity and the role of exercise in both these conditions.

Charaka

Charaka is another prominent physician of ancient India who lived sometime between 100 BC to 150-200 AD. He is well known as the editor of the medical treatise Charaka Samhita, one of the basic books of traditional Indian medicine and Ayurveda. Charaka Samhita has been divided into eight parts, and in each part, exercise (vyayama) has been referred to multiple times, with more than 120 verses (shlokas) on exercise (vyayama) (7). Like Sushruta, he advocated moderate exercise for most diseases; however, to “cure” diabetes, he recommended strenuous exercise (6).  

Physicians from the ancient Greek civilisation

Three ancient Greek physicians recognised the significance of exercise in human health.

Herodicus

Herodicus (500 BC), a former teacher of Hippocrates, was a Greek physician and former exercise instructor  (8). His dual expertise combined gymnastics with medical science paving the way for subsequent Greek study of the health benefits of exercise. He was the first to study therapeutic gymnastics – or gymnastic medicine, as it was often called (8) and has been designated as the “father of sports medicine” (9).

Hippocrates

Hippocrates (460 BC to 375 BC) is traditionally regarded as the father of medicine. While Sushruta was the first “recorded” physician to prescribe moderate daily exercise, Hippocrates was the first “recorded” physician to provide a written exercise prescription for a patient suffering from consumption. Hippocrates has written in detail on the benefits of exercise in his writings Regimen in Health and stated, “Eating alone will not keep a man well; he must also take exercise. For food and exercise, while possessing opposite qualities, yet work together to produce health” (8, 6, 10). Furthermore, he regarded that idleness (inactivity), excessive exercise, and excessive food consumption (compared with exercise) could lead to disease (6).  

Galen

Claudius Galenus or Galen (129-210 AD) was a Greek physician, author, and philosopher, who worked in Rome, a former physician of gladiators, and was the most influential physician of the Roman Empire. Galen, who borrowed much from Hippocrates, made his own significant contributions to the field of medicine. He wrote numerous works of great importance to medical history, including his book entitled On Hygiene, which provides the most information on the role of exercise in promoting good health. He stated, “Whether by sailing, riding on horseback, or driving, via cradles, swings, and arms, everyone, even infants, needed exercise.” (8). His belief that health could be improved through one’s own actions, such as eating right and getting enough sleep and exercise, cast a major influence on medical theory as it developed over the centuries (8).

His “medical theory” was based upon the “naturals” (of or with nature, i.e., physiology), the “non-naturals” (things not innate – i.e., health), and the contra-naturals (against nature – i.e., pathology. Hygiene (named after the goddess of health, Hygieia) and the uses and abuses of the “six things non-natural” were central to Galen’s medical theory. The “six things non-natural” included: 1) Air, 2) food and drink (diet), 3) sleep and waking, 4) motion (exercise) and rest, 5) excretions and retentions, and 6) passions of the mind (10, 11). Galen’s medical theory was bolstered by the above “six things non-natural”, which were factors external to the body and not innate and over which a person had some control. Galen proposed that these factors should be observed and practised in moderation to promote good health. But if these are not followed adequately or performed in excess, that would create an imbalance in the body and lead to illness or disease (10, 11).

During Galen’s era, exercise was prescribed for multiple diseases (6). Notably, while Galen recommended exercise for treating various ailments, including gout, dyspepsia, and consumption, among others, exercise was primarily used for prophylaxis (10). In his text, Galen emphasised the need for exercise (motion) in all ages and described work as both “movement and exercise”. Because of the influence of Galen, exercise was advocated for the promotion of good health and minimisation of the consequences of disease until the beginning of the 16^th century (6).  

Role of exercise for health in the medical literature

The significance of non-natural traditions and the importance of exercise for good health abound in the medical literature. Spanish physician Christobal Mendez, in 1553, wrote the first printed book devoted to exercise entitled Book of Bodily Exercise (8, 10). He wrote, “The physician must organise his patient’s life and the things called unnatural, such as eating and drinking, evacuation and retention, sleep and vigil, movement and rest, and the passions of the soul and alteration of the air.” He further stated that “if we use exercise under the conditions which we will describe, it deserves lofty praise as a blessed medicine that must be kept in high esteem” (8, 10).

Another text on the subject of exercise in relation to health and medicine, entitled The De Arte Gymnastica, was written by a great Italian physician, Girolamo Mercuriale (1530-1606), usually known by his Latinized name, Hieronymus Mercurialis, in 1569 (12). After describing the physical training and gymnasia of the ancients, Mercuriale systematically highlighted the importance of exercise in the prevention of disease, preservation of health, the development of bodily function, and the treatment of affections.

In 1724, An Essay of Health and Long Life by George Cheyne was published in London. Over the next two decades, it went through 10 editions and numerous translations. He recommended walking as the “most natural” and “most useful” exercise but considered riding on horseback as the “most manly” and “most healthy”. In the early 1700s, a physician in London, Francis Fuller, published Medical Gymnastics: A Treatise Concerning the Power of Exercise. In 1747, John Wesley published a book entitled Primitive Physic. In his preface, he wrote that “the power of exercise, both to preserve and restore health, is greater than well can be conceived; especially in those who add temperance thereto” (8). About a decade later, in 1769, Scottish physician William Buchan published a book entitled Domestic Medicine, which became highly popular. He recommended that “of all the causes which conspire to render the life of man short and miserable, none have greater influence than the want of proper exercise.” He also explained that “exercise alone would prevent many of those diseases which cannot be cured, and would remove others where medicine proves ineffectual” (10).  

In 1780, French physician Clement Tissot wrote a book entitled Medical and Surgical Gymnastics. Under the subtitle’ Essay on the Usefulness of Movement, or Different Exercises of the Body, and of Rest, in the Treatment of Diseases’, he emphasised the importance of both active and passive exercises as well as the essentiality of exercise for rehabilitation after surgery (10). During the 19^th century, the classical Greek tradition and general hygiene movement found their way into the United States through American editions of Western European medical treatises or books on hygiene written by American physicians (8). Subsequently, the “six things non-natural” came to be known as the “Laws of Health” (10) and were expressed as “value prescriptions” (8, 13).

In 1830 John Gunn published his classic Gunn’s Domestic Medicine Or Poor Man’s Friend. The “Exercise” section recommended temperance, exercise, and rest and valued nature’s way over traditional medical treatment. Notably, he recommended a training system for all. He emphasised: “…were training introduced into United States and made use of by physicians in many cases instead of medical drugs, the beneficial consequences in the cure of many diseases would be very great indeed” (8).

During the later part of the 19^th century, efforts were made to popularise the Greek laws of health and make individuals responsible for maintaining their health. Therefore, individual reform writers discussed the importance of self-improvement, self-regulation, the responsibility for personal health, and self-management. “If people ate too much, slept too long, or did not get enough exercise, they could only blame themselves for illness. By the same token, they could also determine their own good health” (8). Notably, the Greek “physis” meant “nature” or “natural” and was the root of “physick”, the term used for medicine into the 1700s and also for the present-day term “physician” (10).  

Medical literature on the role of physical inactivity in the causation of diseases

Besides the role of exercise in preserving and maintaining good health, medical literature over the last few centuries abounds on the role of physical inactivity in the causation of diseases. An English physician Thomas Cogan recommended his book The Haven of Health, published in 1584, to his students who, because of their sedentary lifestyles, were believed to be most prone to ailments (8). An Italian physician Bernardino Ramazzini, considered to be the father of occupational medicine, in his book Diseases of Workers, published in 1713, wrote about chronic inactivity and poor health. In the chapter entitled “Sedentary Workers and Their Diseases”, he wrote – “those who sit at their work and are therefore called ‘chair workers’, such as cobblers and tailors, suffer from their own particular diseases.” He concluded that “these workers…suffer from general ill health and an excessive accumulation of unwholesome humors caused by their sedentary life”, and he encouraged them to at least exercise on holidays “so to some extent counteract the harm done by many days of sedentary life” (8).

A New York physician, Shadrach Ricketson, In his book Means of Preserving Health and Preventing Diseases, published in 1806, explained that “a certain proportion of exercise is not much less essential to a healthy or vigorous constitution, then drink, food and sleep; for we see that people, whose inclination, situation, or employment does not admit of exercise, soon became pale, feeble, and disordered” (8, 10) and warned that “idleness and luxury create more diseases than labour and industry” (10).

The emergence of ‘Physical Education’ as a profession

During the 19^th century in America, the “laws of Health” found further expression through new literature and profession devoted to physical education. In the early part of the century, this term was used by many physicians in their journal articles, speeches, and books to describe the task of teaching children about the ancient Greek’ laws of health’ (8, 10). As AFM Willich, a German medical writer, explained in his “lectures on Diet and Regimen”, “by physical education is meant the bodily treatment of children; the term physical being applied in opposition to moral.” In those early days, physical education meant much more than merely exercising the body; its essence was maintaining health (8, 10). Books like Thoughts on Physical education, written in 1834 by Charles Caldwell, a physician from the Transylvania University Medical School and Physical Education and Preservation of Health, written in 1845 by John Warren, a Harvard medical school physician, helped birth the “physical education” movement in America (10).  

By the 1880s, the “physical education” movement led to the formation of the American Association for the Advancement of Physical Education. This professional body was founded by, dominated by, and presided over by physicians (MDs) who held faculty appointments at major American universities like John Hopkins, Yale and Harvard. The dominance of physicians in physical education was such that out of the first 12 presidents of this association, 11 were physicians (10). Besides, physicians dominated other bodies related to physical education. In 1897, out of the 16 members of the Society of College Gymnasium Directors, 12 were MDs. In the early 1900s, the editor of the American Physical education review was an MD. In 1903, the entire executive committee of the American Society for Research in Physical Education comprised MDs. Besides, in 1904, out of the 20 American Physical Education Association’s National Council members, 15 were physicians, including the President and Vice President. Most of the physicians who taught “physical education” carried out varied tasks, including taking anthropometric measurements, prescribing exercise, giving health lectures, and supervising the new gyms built on college campuses that the Superintendent of Public Instruction in Massachusetts called “Palaces of Health” (10).

One such physician, J. William White, a faculty member at the University of Pennsylvania, in 1887 wrote an article A physician’s view of exercise and athletics in Lippincott’s magazine. He wrote: “Let it be understood that the main object and idea of exercise is the acquirement or preservation of health; that it is by far the most important therapeutic and hygienic agency at the command of the physician today; that it can be prescribed on as rational a basis with as distinct reference to the correction of existing troubles or the prevention of threatened ones as any of the drugs of the pharmacopeia” (10).

Accordingly, due to their perceived importance, by 1900, all states in the US mandated the teaching of the “Laws of Health”, which were incorporated into the curriculum of physical education. Interestingly, one of the earliest books about physical fitness as we know it today, Health, Strength & Power, was written in 1904 by Harvard physician Dudley Sargent (10). Another physician and physical educator, R. Tait McKenzie, from the University of Pennsylvania, in 1909 wrote a book, Exercise in Education and Medicine, which is further testimony to this long-established link between exercise, health and medicine (10).

Changes in the American Medicine and “Physical Education” systems

However, by the early 1900s, both the field of medicine and physical education began to undergo significant changes. Scientific research led to the evolution of newer treatments and diagnostic techniques. Bacteriology and germ theory which displaced the ancient humoral theory, changed past beliefs about public health, disease, and infections. New drugs were available that could now cure; this, combined with the emergence of new surgical techniques, shifted the emphasis to treating rather than preventing the diseases (10). Fighting infectious diseases like influenza, yellow fever, smallpox, diphtheria, typhus, cholera and tuberculosis and finding effective vaccines for these became a greater priority for physicians. Gradually, the medical profession shifted from “health care” to the “sick-care” model wherein greater emphasis was placed on cure rather than prevention.

As medical science progressed, most physicians began to specialise. As a result, more and more physicians did not find “physical education” as a field of potential employment or one where their expertise would be best utilised or appreciated. Accordingly, the exercise began to lose the attention previously displayed by many physicians (10).

Around the same time, in the early 1900s, “physical education” began to experience a shift in emphasis from body development and health instruction to games and sports. In the mid-19^th century, a philosophical movement known as Muscular Christianity originated in England. The basic premise of this movement was that participation in sports could contribute to the development of Christian morality, physical fitness, and “manly” character (14). The movement is often associated with English author Thomas Hughes, his 1857 novel Tom Brown’s School Days, and another writer, Charles Kingsley. Both Hughes and Kingsley were keen sportsmen and advocates of the strenuous life. Both believed that the Anglican Church had become weakened by a culture of effeminacy and viewed manliness as an “antidote to the poison of effeminacy – the most insidious weapon of the Tractarians – which was sapping the vitality of the Anglican Church” (14).

During the late 1850s, the tenets of Muscular Christianity became an integral part of the public school educational system. The notion of Kingsleyan manliness was the main driving force behind the Muscular Christianity movement within public schools. The sport of Rugby was particularly popular because it provided enough opportunity to “take hard knocks without malice”, a desirable attribute in possible future leaders (14).

This movement also influenced the founding of the British Young Men’s Christian Association (YMCA) in London in 1844 by George Williams. Even though, at its inception, YMCA emphasised “…bible-study, prayer and education” and disapproved of sport and athletic activities as an unwanted distraction from evangelism, however, towards the end of the 19^th century, as Kingsleyan manliness became a pervasive theme in evangelical literature and rhetoric, the concept of Muscular Christianity was thoroughly institutionalised into the YMCA. This resulted in the proliferation of gymnasia and health and fitness programs within the YMCA on both sides of the Atlantic (14). The invention of Basketball by James Naismith, a Canadian-American physical educator, physician, Christian chaplain and sports coach, who was an instructor from the International YMCA Training School in Springfield, Massachusetts, in 1891, spurred a massive gymnasium building spree to accommodate this new indoor game. Gradually, basketball joined games like football, baseball, swimming, track and field, and tennis, among several other games and sports, to become the new subject matter of physical education (10).

Accordingly, men and women with expertise in these sports and who could teach and coach these new games replaced physicians in the metamorphosed “physical education” system. Furthermore, gyms which earlier featured a variety of exercise equipment and were built to support a curriculum designed to improve and maintain health and were the domain of physicians, now featured basketball courts and bleachers for adoring fans. These remodelled or newly built gyms became new classrooms for physical education. This greatly impacted the role of physical education in high schools and colleges; its goal of “education of the physical” changed to “education through the physical”. Gradually the moral and educational benefits of playing games overshadowed their health promotion values (10).

Physical education had now become a sports skills program and was directly linked with intramural, interscholastic, and intercollegiate sports. As games and sports became central to physical education, their competitive nature catered only to students more highly skilled and the majority who were not athletically inclined were neglected (10). This problem was highlighted in a JAMA article in 1905 – “The men on the teams are the very ones whom Nature has endowed superabundantly with physical capacity, but on them, the physical director spends most of his energies, while the average student is left to get his physical development by yelling from the bleachers” (10).

Notably, Edwards, in his book Sociology of Sport (15), noted, “The Sports Creed emphasising citizenship, teamwork, character, democratic living, and sportsmanship had replaced the “Laws of Health” as the focal point for physical education.” In the changed scenario, where the physical education curriculum focused on competitive sports, coaches and not physicians were hired, and students endowed with physical attributes were favoured, while those not so fortunate got a very little exercise. In sum, the hallowed role that exercise once played in people’s health was lost in the glamour of new games and sports, where success was defined by wins and losses rather than the overall health of the students at large (10).

The fallout of the new physical education system

The fallout of the new physical education started manifesting as early as World war I when almost one-third of the American conscripts during World War I were found to be inadequately fit to serve their country (8, 10). Similarly, even during World War II fitness results of draftees and enlistees were dismal (10).

The problem continues to grow, and as discussed above, physical inactivity has now emerged as the biggest public health problem of the 21^st century and may be more detrimental to health than cigarette smoking and obesity (2). Along with tobacco use, unhealthy diet, and harmful use of alcohol, physical inactivity is one of the major risk factors for this pandemic. A pooled analysis of 298 population-based surveys with 1.6 million participants (16) highlighted that globally, in 2016, 81% of students aged 11-17 years were insufficiently physically active; girls were more inactive compared to boys 84.7% vs 77.6%. Another pooled analysis of 358 population-based surveys with 1.9 million participants (17) found that 27.5% of adults currently do not meet WHO’s recommended levels of physical activity; as for adolescents, there was a difference between sexes of more than eight percentage points (23.4% in men vs 31.7% in women).

This will have a huge adverse impact on not only individuals over their life span and their families but also health services and society. According to the WHO’s Global status report on physical activity 2022, published on 18 Oct 2022 (18), physical inactivity has a huge economic burden. Worldwide, between 2020 and 2030, almost 500 million (499 208 million) new cases of preventable noncommunicable diseases will occur and will incur treatment costs of just over US$ 300 billion (INT$ 524 billion) or around US$ 27 billion (INT$ 48 billion) annually, if there is no change in the current prevalence of physical inactivity. More worryingly, three-quarters of all cases will occur in lower- and middle-income countries, where healthcare infrastructure is inadequate and overstretched. While low- and middle-income countries have a larger proportion of the disease burden, high-income countries will bear the largest economic cost, accounting for 70% of healthcare expenditure on treating diseases resulting from physical inactivity.

Furthermore, with more and more people failing to meet physical activity guidelines, Global deaths per year attributed to physical inactivity may soon overtake deaths ascribed to smoking (19). To address the issue, WHO has launched a Global Action Plan on Physical Activity 2018-2030 with the theme More Active People for a Healthier World (20). Its goal is to reduce physical inactivity by 10% by 2025 and 15% by 2030.  

As is evident from the above discussion, exercise was a key part of ancient medical theory, and the preservation and promotion of health, as well as the prevention of diseases, were part of the physician’s duties. Ancient physicians across all major civilisations prescribed exercise as part of the regimen to manage, minimise or treat the effects of diseases. Although much of what they believed to be true has been disproved, they did emphasise the importance of exercise and physical activity for health and laid the foundation for the development of exercise science as a medical discipline. Notably, nearly 2.5 millennia later, the debate about exercise and its effects on health continues with little understanding beyond the teachings of these ancient physicians.

As discussed, physical education, once dominated by physicians, changed to games and sports led by coaches, who introduced competition and athletic achievement into the classroom. This gradually overshadowed the anointed role of exercise in the body development and health of students. As this transformation took place, physical education moved out of the domain of physicians, and they gradually disappeared from the profession of physical education.

The role of physicians in exercise prescription comes full circle

In 1927 Harvard Fatigue Laboratory was established at Harvard University. The collective body of work by various investigators led to the recognition of exercise physiology as an important area of research and study in its own right. Nearly four decades later, the first academic department of exercise physiology came into existence, hitherto having been part of the physical education department (21). This led to the recognition of the importance of exercise physiology in health and wellness, among others.

In 1954, the American College of Sports Medicine (ACSM) was founded by a small group of physical educators and physicians who recognised that certain lifestyles, especially smoking and lack of exercise, were associated with various health problems. A large contingent of physicians, who were both founders and charter members of ACSM, through partnerships with groups like the American Heart Association and the American College of Cardiology, brought exercise back into the physicians’ domain (10). Now a great deal of exercise science research dealt with different aspects of physical activity, fitness and health. An important event in the revival of the almost 2.5 millennia old concept, forgotten over the last century, was the co-launching of ‘Exercise is Medicine: A Global Health Initiative’ by the ACSM and the American Medical Association (AMA) on 05 Nov 2007 (10). This initiative seeks to make physical activity assessment and exercise prescription a standard part of the disease prevention and treatment paradigm for all patients.     

Another significant development in the revival of exercise prescription becoming part of the physician’s role was the advent of a new clinical discipline – “lifestyle medicine”. The term lifestyle medicine resulted from the association of lifestyle (chronic or noncommunicable) diseases with people’s lifestyles. Lifestyle medicine fills the gap between public health, focusing on health promotion, and clinical practice, by adding behavioural, motivational, and environmental skills to conventional medical practice. The term lifestyle medicine was first used in 1989 as a title of a symposium and first appeared in publication in 1990 as a title of an article (22). Lifestyle medicine has been defined in many different ways and has changed over time. However, the common point of these definitions is the focus on lifestyle modifications for the prevention, treatment, and rehabilitation of various lifestyle diseases. Exercise is one of the important pillars of lifestyle medicine.   

Significance of physical activity prescription by physicians

As per a study by Weiler et al., approximately 25% of the people in England were willing to become physically active if they were advised to do so by a general practitioner (GP) or nurse, and yet 54% of the patients reported not even being advised on diet and exercise by their GP (23). Though exercise physiologists and other exercise professionals are being trained and certified in exercise prescription, however, for various reasons, physicians are better positioned to provide exercise counselling to their patients.

Firstly, physicians have a unique position in the health care system, as a large majority of patients visit a physician at least once annually. Patients with lifestyle diseases visit their physicians more frequently, which enables a physician to provide ongoing preventive counselling, feedback, and follow-up. Secondly, physicians are viewed as the most credible and respected source of health-related information; hence, patients prefer to get health-related information directly from their physicians. Finally, because of the substantial health benefits of physical activity, including the prevention of various lifestyle diseases, physicians may be ethically obligated to prescribe exercise to sedentary patients to reduce their risk of chronic health conditions (24). This obligation is an example of one of the six basic principles of medical ethics; ‘Salus aegroti suprema lex’ (Beneficence – “A practitioner should act in the best interest of the patient”) (25). Accordingly, healthcare providers, particularly physicians, are expected to provide evidence-based preventive counselling to their patients, including exercise prescriptions.

Furthermore, several studies have shown that simple physical activity counselling by general practitioners to sedentary patients can help reduce physical inactivity (26). A randomised controlled trial (27) also found that intervention by family physicians was effective in increasing physical activity in physically inactive patients. Another study (28) examined the effect of physician counselling on the physical activity levels of patients over 20 months. The study found that physician counselling effectively increased physical activity in patients over the long term.  

Prevalence of exercise counselling by physicians

Despite the great amount of information about the health benefits of physical activity and the effectiveness of physical activity prescription by physicians in improving the physical activity behaviours of patients, rates of physical activity counselling by physicians are low. Only 34% of US adults reported physical activity counselling by their physicians at their last visit to the physician (25). Another study (29) found that only 19.2% of the patients reported receiving physical activity advice from physicians. Furthermore, in patients who received physical activity advice, various parameters of exercise prescription, such as frequency, intensity, duration, and type of activity, were not commonly provided. 

Barriers to physical activity prescription by physicians

Barriers exist to all health behaviour change and can be broadly divided as under:

Attitudinal barriers – beliefs about efficacy or the status of physical activity promotion within general practice.

System barriers – time constraints, lack of incentive or reimbursement, lack of standing protocols, lack of success in the counselling role, lack of appropriate training and absence of a coordinated and systematic daily approach in practice operations.

Physicians’ health behaviours – Physicians’ (25, 30) and medical students’ (25) own physical activity habits are important predictors of their practice of physical activity history taking and exercise prescription.

Patient barriers – limited time, fatigue, family obligations (especially for caregivers), or other competing priorities.

Role of physician’s own physical activity habits in exercise prescription

Studies have shown that physicians’ own physical activity habits influence their practice of physical activity history taking and exercise prescription as well. Patients also like consistency in their physicians; they respond more positively to exercise promotion when they perceive that the doctors “walk their talk”. 70% of a family medicine centre patients reported that this would motivate them to comply with the physician’s recommendation to exercise more (31).

Studies have shown that physicians who themselves act on the advice they give are more likely to provide better counselling and motivation to their patients to follow such health advice (25). Early evidence of the association between physicians’ own Physical activity habits and their exercise prescription habits was shown in the US Women Physicians Health Study (WPHS) (32). Women physicians who followed physical activity recommendation guidelines were more likely to advise patients on exercise, counsel confidently, and be trained in counselling. Furthermore, those who perceived exercise as a high priority were more likely to advise patients on exercise (33). In contrast, physically inactive physicians were less likely to provide exercise counselling to patients and were less reliable role models for adopting healthy behaviours (25).  

A subsequent study, the Healthy Doc = Healthy Patient (HD = HP) project, examined the effects of the medical education received by medical students on their personal and clinical prevention-related practices. The study showed that healthy personal behaviours and attending a medical school that promoted healthy personal behaviours significantly predicted the frequency with which seniors counselled patients about preventive interventions (34).

However, another study based on the Healthy Doc = Healthy Patient (35) presented the most troubling finding from this study; while physical activity levels were relatively stable during four years of medical training, the proportion of students perceiving physical activity counselling in their future practices as highly relevant decreased significantly from 69% in the first year to 53% in the fourth year.

Frank and colleagues further tested whether promoting the health of medical students could efficiently improve patient counselling. For this, they developed and implemented a 4-year curricular and extracurricular intervention to promote health behaviours among students in the class of 2003 attending Emory University School of Medicine, Atlanta, Georgia (36) and used the class of 2002 as controls (37). Notably, students in the intervention group had about 50% greater odds of providing extensive counselling on healthy behaviours, including diet and exercise, during their standardised patient encounters than those in the control group (37).

A few additional studies have also assessed the association between personal physical activity habits and patient counselling on physical activity. They have also concluded that more physically active physicians are more likely to counsel their patients about the health benefits of physical activity (25). Overall, there is enough evidence to indicate a robust association between personal physical activity behaviours and physical activity counselling practices in both practising physicians and medical students. Besides, studies have demonstrated that physicians’ disclosures of their own healthy behaviours make them more believable and credible, and it improves their ability to motivate patients to adopt an active lifestyle (38).  

The above studies demonstrate a clear link between the health promotion environment in medical schools, the personal health practices of physicians, and their preventive counselling practices in their intended practice. These findings highlight the need to implement programs in medical school aimed at improving physical activity habits and other healthy behaviours in medical students as a strategy to create a healthy physician workforce who counsel patients about prevention.

Integration of exercise assessment and prescription in clinical practice

As highlighted, lifestyle diseases are the leading cause of morbidity and mortality globally. Four modifiable behavioural risk factors, viz. tobacco use, unhealthy diet, harmful use of alcohol and physical inactivity, are primarily responsible for this pandemic of lifestyle diseases (39). Health behaviours have the potential to greatly influence future health and well-being, especially among patients with risk factors for lifestyle diseases or suffering from any of the lifestyle diseases. Changing unhealthy behaviours is foundational to medical care, disease prevention, and health promotion. The United States Preventive Task Force has addressed behavioural counselling as it relates to lifestyle health issues suggesting that “Changing the health behaviors of Americans has the greatest potential of any current approach for decreasing morbidity and mortality and for improving the quality of life across diverse populations” (40). Besides, all well-established chronic disease practice guidelines uniformly call for lifestyle change for the prevention and first-line treatment of various lifestyle diseases. Exercise is the cornerstone of a multifaceted plan to prevent and manage lifestyle diseases.

As highlighted, the WHO’s Global Action Plan on Physical Activity 2018-2030 (20) has set a target to reduce physical inactivity by 10% by 2025 and 15% by 2030. Unfortunately, despite the vast benefits of exercise in disease prevention and health promotion, it remains a grossly under-utilised and under-prescribed therapy. Hundreds of billions of dollars are spent on medications each year (41), but exercising can be free of cost.

Considering the levels of physical inactivity and its impact on the health of the people, the American College of Sports Medicine (ACSM), in consultation with various stakeholders, made a call to action to physicians and the healthcare community for the implementation of physical activity vital sign (PAVS) in clinical practice (19). The PAVS has great potential to be a catalyst for a complete transition from the current ‘sick-care’ model, which emphasises treating diseases, to the ‘health-care’ model, wherein the focus will be on disease prevention and a culture of health and wellness (19). Besides, the integration of PAVS into clinical practice serves two more important purposes. Firstly, it allows the physician to initiate physical activity counselling. Secondly, the routinisation of physical activity screening will impress upon the patients the significance of physical activity in health (42).

Significance of a vital sign in clinical practice – Traditionally, the vital signs measured in routine clinical practice include temperature, pulse rate, blood pressure, and respiratory rate. Unfortunately, barring blood pressure measurement, these vital signs do not provide evidence of the presence of lifestyle diseases, the biggest cause of morbidity and mortality, particularly during their long latency period, when behavioural interventions can prevent or delay the manifestation of these conditions. In the context of lifestyle diseases, physical activity status is the best indicator of a person’s long-term health and likely longevity. Physical inactivity may be more harmful to health than cigarette smoking and obesity (19). As more and more people fail to meet current physical activity recommendations, global deaths per year associated with physical inactivity may soon surpass deaths related to smoking (19). In this background, all clinicians are duty-bound to assess every patient’s physical activity status and educate them about the health risks associated with physical inactivity. Furthermore, clinicians should examine practical ways to help patients overcome barriers to being sufficiently physically active.

Steps for implementation of PAVS in clinical practice

As discussed above, the unique position of the physician in the health care system and the trust patients repose in their physicians, exercise prescriptions by physicians can be one of the best and most cost-effective ways to increase physical activity among patients. An essential first step in this direction is to query their physical activity habits. Physical activity screening is the simplest way to start a conversation about the importance of physical activity (regardless of weight status). Obtaining answers to the following two simple questions during each outpatient visit can give a fair idea of the physical activity status of the patient (19, 43):

1. On average, how many days per week do you engage in moderate to strenuous physical activity (like a brisk walk)? And
2. On average, how many minutes do you engage in physical activity at this level?

The product of the answers to these questions determines the total number of minutes per week the patient performed at least moderate-intensity physical activity level. Kuntz et al. examined the validity of the Exercise Vital Sign (EVS) Tool (44). They found that EVS is useful for assessing physical activity status and correctly identifies individuals who do and do not meet physical activity guidelines.

The literature suggests the third question on strength training as optional. However, considering the role of muscle mass and function and the rapid population ageing globally, there is a need to incorporate this question, under PAVS, on strength training. The question can be framed as:

• How many days per week do you perform muscle-strengthening exercises using external resistance?

For most people, the term ‘exercise’ means aerobic activities like walking, jogging etc. However, as highlighted under health-related components in my post, Exercise is Medicine: but a grossly underutilised therapy, muscular fitness is an equally important component of physical fitness. The health benefits of enhancing muscular fitness are on par with aerobic fitness, if not more. However, its most important and distinctive advantage over aerobic activities is its ability to preserve muscle mass and function, which invariably tends to decline with advancing age.

As discussed under sarcopenia in my post, Healthy Ageing – Adding Years to Life and Life to Years, the ageing process, even in the absence of chronic disease, is associated with a progressive and generalised loss of muscle mass and function and appears to occur even in relatively weight-stable healthy individuals. It is accompanied by loss of muscle strength, which is often greater than what can be accounted for by the loss of muscle mass. This disproportionate loss of muscle strength is due to impaired muscle quality with ageing. This age-related loss of muscle mass and function is termed sarcopenia. Sarcopenia is a major contributor to the risk of physical frailty, a common geriatric syndrome that carries an increased risk for poor health outcomes, including falls, incident disability, hospitalisation, functional decline, poor health-related quality of life and premature death in older people.

Exercise prescription – For patients who do not meet the recommended guidelines for physical activity, physicians should recommend that patients increase their weekly physical activity levels to the recommended amount. The exercise prescription should take into account the FITT-VP factors, as discussed in my post, Exercise Prescription for Optimal Health Benefits. Physicians may also enquire about barriers or challenges preventing patients from being sufficiently physically active. This enables the physician to engage in individualised counselling specific to the patient’s situation. A written exercise prescription is a critical indicator that physical activity and exercise can be therapeutic (30).

However, even though sustaining healthy behaviours is one of the most important things people can do to live long, healthy lives, behaviour change is hard. Behaviour change is complicated and complex because it requires a person to disrupt a current habit while simultaneously fostering a new, possibly unfamiliar, set of actions. To facilitate effective health behaviour change counselling during a medical visit, the 5A guidelines, in which physicians Ask about (or Assess), Advise about, Agree upon, Assist with and Arrange follow-up regarding patients’ behaviour change efforts, are recommended as an evidence-based clinical tool for counselling on health behaviour change. The model was initially developed by the National Cancer Institute of the US as the “4 A’s” for smoking cessation; the 5A’s have been endorsed by the US Preventive Task Force, the Canadian Task Force on Preventive Care, and national guidelines in the UK and Sweden as a unifying framework for health behaviour counselling for health behaviours other than tobacco (45). Health behaviour counselling interventions based on the 5A’s model have proven effective for smoking cessation and physical activity in primary health care set-up (46).

However, as highlighted, in practice, motivating patients to change health behaviours is a frustrating and challenging task. Simply encouraging patients to change their behaviours at the end of a patient visit yields limited results (47). Unfortunately, most physicians who counsel on exercise perform only the first 2 A’s, that is, ask about the physical activity behaviour and advise behaviour change; however, it is the latter, less frequently performed 3 A’s that have the maximum impact on health behaviour change (19). Accordingly, it is recommended to invest in lifelong education of physicians in health behaviour change to improve the practice of physical activity counselling (46).

Approaches to overcome barriers to physical activity counselling by physicians.

As discussed above, physicians face various challenges to physical activity counselling. Strategies to overcome two of the most common barriers, viz. lack of time and training, will be discussed here briefly.

Strategies to overcome lack of time

Lack of adequate time is one of the main barriers to physical activity counselling by physicians. An effective way to deal with the time constraint is to build an interdisciplinary support team around the physician (19, 42). A medical assistant or nurse practitioner can record the PAVS (commonly, it takes less than a minute to query and record PAVS), a physician writes the exercise prescription, an exercise physiologist or a trainer may create an individualised exercise plan based on the exercise prescription, and a health coach or behavioural counsellor may arrange follow-up and help identify resources for the patient.

Strategies to overcome inadequate training

As highlighted above, physicians’ lack of adequate training in exercise counselling is one of the major barriers to counselling patients about physical activity. Unfortunately, despite the huge burden of lifestyle diseases arising from physical inactivity and other unhealthy lifestyle behaviours, medical education, clinical practice and public health strategy continue disregarding physical activity as a tool to prevent diseases and promote good health. This is despite WHO highlighting through various reports (18, 39), issued from time to time, both the disease burden and economic costs associated with physical inactivity, as well as the need to make people more physically active for a healthier world (20). Notably, United Nations General Assembly convened a High-Level Meeting on Noncommunicable Diseases (NCDs) on 19-20 Sep 2011. Heads of State and Government adopted by consensus the resolution titled “Political Declaration of the High-level Meeting of the General Assembly on the Prevention and Control of Noncommunicable Diseases” (48). This declaration provides a roadmap for Member States and WHO to address the noncommunicable disease epidemic. In addition to WHO, various national organisations and institutions of several countries have issued guidelines for promoting physical activity. Thirty-nine different disease-specific clinical guidelines also support physical activity and exercise promotion, usually as a primary treatment and management recommendations, covering a wide range of diseases and conditions (49). The paper raises the possibility of a doctor being sued for failing to provide physical activity counselling to their patients, given that exercise is known to be one of the highest modifiable risk factors for morbidity and mortality.

Unfortunately, all these efforts do not seem to have produced significant tangible results. One main reason for this failure appears to be that all these policies have failed to target one of the major stakeholders in health care, providers – the healthcare professionals. To be able to fight the battle against the raging pandemic of lifestyle diseases, physicians must understand the basic science and health benefits of physical activity alongside other lifestyle interventions.

However, despite the growing number of clinical and public health guidelines, physicians are neither trained, experienced, nor confident to provide physical activity counselling to their patients (23). Bull and Bauman described physical inactivity as the Cinderella of NCD risk factors, defined as “poverty of policy attention and resourcing proportionate to its importance” (50). Changing this situation will require a substantial transformation of the healthcare system and medical education, including integrating physical education in its new avatar – exercise medicine, into undergraduate, graduate, and continuing medical education (19).

Undergraduate-level medical school curriculum

Almost four decades ago, it was acknowledged that given the growing evidence that physical activity was important in the management, treatment, and prevention of disease as well as the promotion of health, physical activity education should be introduced in the curriculum in medical schools. A basic understanding of the health benefits of physical activity, ways to effectively promote physical activity using health behaviour change techniques, and address sedentary behaviour across all ages, underpin the ability of future physicians to handle the present-day pandemic of lifestyle diseases (23).

Notably, the inclusion of physical activity education in the medical school curriculum increases the chances of medical students becoming physically active, having improved fitness, and having more favourable attitudes towards physical activity and the outcomes of counselling (19).

As discussed above, the Healthy Doctor = Healthy Patient project demonstrated that in both developed and developing countries, the physical activity habits of medical students were associated with a more positive attitude towards physical activity counselling. When physicians understand the health benefits of physical activity and engage in exercise, they are more likely to appreciate its value as a preventive and therapeutic tool. In this background, besides introducing exercise medicine as part of the medical school curriculum, students should be encouraged to adopt and maintain regular physical activity habits. This can be a powerful strategy to improve future physicians’ attitudes towards physical activity counselling. Subsequently, this could play a decisive role in our battle against the present-day scourge of lifestyle diseases.

Graduate-level medical education

Physical activity education and training are not part of the residency and fellowship programs. Several studies have demonstrated that lower preoperative physical activity status and/or cardiorespiratory fitness leads to poor outcomes in most patients with chronic diseases and those undergoing elective or emergent surgery (19). Pitsavos et al. demonstrated that engaging in simple, inexpensive lifestyle modifications, such as regular physical activity, is associated with reduced severity of the acute coronary syndrome, lower in-hospital mortality rates, and better short-term prognosis (51).

Smith et al. evaluated the association between preoperative cardiorespiratory fitness and short-term morbidity and mortality after coronary artery bypass grafting (CABG). The study found that after adjusting for potential confounding variables, lower preoperative cardiorespiratory fitness was associated with higher complications after CABG, including higher operative and 30-day mortality after CABG (52). McCullough et al. examined the association between preoperative cardiorespiratory fitness and complications after bariatric surgery. The study found low preoperative cardiorespiratory fitness was associated with higher short-term complications after bariatric surgery (53). Accordingly, the authors recommended that cardiorespiratory fitness be improved before bariatric surgery to reduce postoperative complications. “Better in, Better out” is a participatory, preventive, predictive and personalised perioperative exercise training intervention which could be implemented in a vulnerable group of patients undergoing major elective surgery who are at risk for prolonged hospitalisation, complications and/or death (54). 54.

Given the above, it is warranted that exercise medicine be part of all graduate residency and fellowship programs. Most importantly, the emerging field of Lifestyle Medicine should be recognised as part of mainstream medical specialities.     

Continuing Medical Education Programs

While focusing on interventions to improve future physicians’ attitudes towards exercise counselling, it is paramount to educate practising physicians about the significance and health benefits of physical activity and empower them to counsel patients on physical activity at every visit. The CME activity is effective in changing the behaviour of some physicians (55).

An appeal to the American College of Sports Medicine

As discussed, the concept that exercise could be medicine is not new – this concept is almost 2.5 millennia old. Given the same, it is requested that ACSM voluntarily give up its patent right on the phrase ‘Exercise is Medicine’, a very ‘common’ phrase. Furthermore, to recognise the contribution of physicians over the ages, the phrase Exercise is Medicine should be replaced by a more appropriate phrase, Exercise: The Medicine Since Antiquity.

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