Physical activity learning by medical students: the current picture in Brazil

Introduction: Physical activity is essential for preventing and treating many diseases. Although physicians are the most influential health professionals in advising their patients on the benefits of physical activity, most medical degree programs in Brazil do not seem to include physical activity topics in their curricula. Objective: This study aimed to investigate physical activity topics on active medical curricula in Brazil. Method: The research was conducted separately in April 2015 and February 2019 using a governmental resource, the e-MEC system, and search in internet databases. Data were split into categories according to the type of enrollment (mandatory or optional) of the courses that have subjects or thematic modules with topics on physical activity, type of activities (theoretical, practical, or theoretical-practical), and emphasis on the content (health, performance, or health and performance). Results: Of the 223 medical curricula compiled in 2015 and 286 in 2019, respectively, only 24 (10.8%) and 19 (6.7%) had at least one subject or thematic module concerning physical activity with emphasis on health. Conclusion: In Brazil, the number of undergraduate medical curricula covering physical activity topics is still small and suffered a reduction between 2015 and 2019, which should warn medical education institutions about the need to include physical activity longitudinally distributed contents, with theoretical and if possible practical approaches, and emphasis on health promotion and treatment of diseases, in mandatory curricular units.


INTRODUCTION
Physical activity (PA) has been recognized for centuries as an important contributor to health promotion [1][2][3] . According to Hippocrates (460-377 BC), a prominent philosopher considered the father of modern medicine and even the first physician to provide a written exercise prescription 4 , "if we could give every individual the right amount of nourishment and exercise, not too little and not too much, we would have found the safest way to health" 2 . Also, Plato (424-348 BC) said that the "lack of activity destroys every human being's good condition, while movement and methodical physical exercise save it and preserve it" 3 . An old Indian medicine book reports that the first definition of physical exercise was recorded around 700 BC as any physical action capable of producing bodily stability and strength 1 . Nowadays, physical activity (PA) is defined as "any bodily movement produced by skeletal muscles that results in energy expenditure, but does not include the effect of dietinduced thermogenesis"; and physical exercise (PE) as "a subset of PA that is planned, structured, and repetitive and has as a final or an intermediate objective the improvement or maintenance of physical fitness" 5 .
The World Health Organization (WHO), which endorsed this concept of physical activity, the Brazilian Society of Sports Medicine and Exercise 6 , and nine more sports medicine societies 7 , have intensively emphasized the importance of PA in health promotion. Physical inactivity is reported as one of the leading causes of disability and mortality 8 , with significant economic 9 and social [10][11][12][13] impact, making it one of the most urgent health problems of the 21 st century 9 . PA plays an essential role in preventing and treating several chronic illnesses [14][15][16][17] , mainly noncommunicable diseases (NCDs) 18 . Mortality from these diseases is rapidly increasing worldwide and already accounts for more than half of the global deaths under 70 years of age 19 . In low to middle-income countries, such as Brazil, the risk of premature death from NCDs is 1.5 times higher than in high-income countries 20 . Therefore, it is indisputable that people must be physically active and the governments must apply PA as a public policy 9,21 .
Several studies have shown that medical counseling encourages patients to change behaviors towards healthier lifestyles, and this represents an essential strategy for health promotion 7,[22][23][24][25][26] . Besides, the promotion of physical activity in medical education could increase students' advising skills aiming to modify patient behavior 27 . Therefore, physicians and other health professionals should encourage the practice of PA and warn patients about the risk of physical inactivity 28 . These physician-induced behavioral changes in patients' lifestyles should be better accomplished by including PA in the undergraduate institutional curricula or training 21,29 . In this context, in addition to the theoretical knowledge, the medical students' practice of PA might also be a significant additional factor for counseling 30,31 , and might contribute to necessary medical training and not only for the sports medicine specialty 7 .
The existence of static and outdated curricula undermines professional health education considering the constant updating of the global health system and the emergence of new health risks 32 . In recent years, discussions on medical education in Brazil have been stimulated, and they have, in general, emphasized the need to adopt active methodologies as pedagogical strategies 33,34 . Although those discussions point out that the physicians from the 21 st century should have transdisciplinary training that allows them to exert multi-professional activities aiming to improve the health problems solutions 33 , no mention of PA among these multiprofessional activities has been reported.
In some countries, PA introduction in medical education has been stimulated [35][36][37] to prepare medical students for physical activity counseling to prevent and treat diseases. In Brazil, we still do not have a picture of this situation. Since the need to prepare medical students for physical activity counseling to prevent and treat diseases is a critical one, this study investigates PA topics regarding the Brazilian active medical curricula.

Ethical Aspects
This study does not require prior approval by an ethics committee since public access to academic curricula is guaranteed by law 38 .

Data Collection Instruments
Initial searches were carried out on the MEC website

Data Collection Procedures
The compiled curricula were randomly divided into three groups. Two independent reviewers analyzed each group regarding the presence of topics on physical activity (PA) in the name of the curricular unit, i.e., subject or thematic module (S/ TM), and/or in its respective syllabus. PA presence as a main or secondary topic within a broader topic in the syllabus was considered an approach to the subject. In case of disagreement between the two researchers examining a curriculum, the study coordinator resolved the dispute. It is essential to note that throughout this study, the term PA refers exclusively to the definition adopted by the WHO 5 .

Qualitative Data Analysis
Subsequently, the information was filtered to reduce possible selection biases, and then the data were pooled. The S/TMs were classified according to the type of enrollment (mandatory or optional), type of activity (theoretical, practical, or theoretical-practical), and emphasis on the content (health, athletic performance, or health and athletic performance).
Therefore, this study consists of documentary research using pre-existing thematic categories.
S/TMs classification concerning the type of enrollment and type of activity was made based on the information collected from each institution's web site. S/TMs with only theoretical activities were considered theoretical; those comprising any practical activity, aiming recreation or training, were considered practical; S/TMs with the simultaneous theoretical and practical activities were considered theoretical-practical.
The S/TMs classification concerning the emphasis (health, performance, or both) was made in an inferential way.
The S/TM titled Exercise Physiology: From Normal to Pathological, for example, which was found in one institution located in the state of the São Paulo, has focused on the associations of physical exercise with either cardiac ("acute and chronic effects of physical exercise on the cardiovascular system") or respiratory ("acute and chronic effects of physical exercise on the respiratory system") systems, and this characterizes it as having an emphasis on health. On the other hand, the S/TM Sports Medicine, which was found in another institution in the state of São Paulo, has guidelines for evaluating athletes, among other items, which means that it emphasizes athletic performance. In some situations, the emphasis was on health and athletic performance, as observed with the S/TM Exercise and Sports Medicine, found in one of the institutions in the state of Rio de Janeiro. The excerpts "to develop skills in the evaluation of athletes" and "clinical bases for the prescription of exercise in health and disease" present in its syllabus denotes a concern with both athletic performance and health.

Quantitative Data Analysis
The present study does not have a sample calculation with a description of statistical power because its objective was to analyze the universe of curricula made available by the institutions. The selected S/TMs were subsequently classified according to the type of enrollment (mandatory or optional), type of activity (theoretical, practical, or theoretical-practical), and emphasis on the content (health, athletic performance, or health and athletic performance).
The number of S/TMs with PA content in each category was then converted into frequency (%).  In 2019, the undergraduate program in Acre (AC) adopted a new curriculum and began to consider that topic as optional but added four subjects containing the topic of PA (Integrated Practices Health I, II, III, and IV).
In general, the curricular unit of Sports Medicine and other similar ones, which are not mandatory, are focused exclusively on performance.
It is worth mentioning that S/TM on pharmacology was mandatory in all assessed curricula.     Overall, the 2019 search showed that when S/TMs containing topics on physical activity were mandatory, PA was only a small part of a broad administered content (e.g., Geriatrics, Locomotion, Integrated Health Practices, among others).
There were some S/TMs (e.g., Exercise and Sports Medicine, in Table 1; Geriatrics, in Table 2) that appeared twice or more in only one federation state because they belong to different medical curricula.

DISCUSSION
To the best of our knowledge, this is the first study that investigated the presence of PA topics in the Brazilian medical schools' curricula. Since regular physical exercise is widely known to bring people many health benefits 17,[39][40][41][42] , in addition to reducing health care expenses [43][44][45]  It is worth mentioning that this reduction in curricular units that address PA occurs in the context of an increase in chronic diseases and their risk factors in Brazil 46 , which is absolutely unjustifiable, since physical exercise is one of the greatest allies in the prevention and control of these diseases 47,48 .
About one-third of the world population is physically  inactive 49 and overweight, and obesity rates are alarming and have been increasing over the years 50 . In Brazil, 41.2% of men and 50.4% of women are physically inactive 51 . It is a consensus among experts that PA itself contributes substantially to health promotion. Up to 80% of coronary heart disease, 90% of type 2 diabetes, and one-third of cancers can be prevented by healthy habits, maintaining a desirable weight, and regular physical activity 52 . Also, at least 13 different cancer types show a risk reduction by leisure-time physical activity practice 53 . Physical activity contributes to the regulation of the immunological system and reduces systemic chronic inflammation 17,40,41 , which is the leading cause of comorbidities and death worldwide 17 .
As mentioned before, increasing the practice of PA has become an important global issue. Physical inactivity is one of the leading causes of disability and mortality 8 , with great economic 9,45 , and social [10][11][12][13] impacts, making it one of the most urgent health problems of the 21 st century 9 . Therefore, PA should be prioritized worldwide as part of a comprehensive strategy to reduce illnesses, especially the NCDs 17,45 . In this context, recently, Arocha Rodulfo suggested that a sedentary lifestyle should be considered a disease 54 . This suggestion makes sense.
Muscles work as an endocrine gland 55 and can interfere in all human systems 17,39 . In turn, PA is essential to modulate muscle epigenetics 56 , promoting the release of thousands of proteins into the bloodstream 57 .
We observed that pharmacology contents appear as mandatory during the curricula evaluation, without exceptions.
This observation contrasts with the presence of PA topic, which occurs in medical curricula as an exception and not a rule. However, PA may behave as a medication 2,14,39,58 in many cases, with actions comparable to or even superior to drug interventions 14 . While some medications used to treat the most common conditions, such as NCDs, may increase the risk of other diseases 59-63 , PA may even modulate the immune system, contributing to the prevention and/or treatment of several illnesses 40,41 , and increase longevity 64 . This action of PA is why the pharmaceutical industry has been searching for pharmacological agents that can mimic the benefits of exercise, the "exercise pill" 65  Although many US medical schools report providing some PA content, the time dedicated to this topic is still lower than that dedicated to other topics, such as nutrition education 35 .
In Australia, most medical schools reported the inclusion of some physical training in their medical curricula.
However, key topics, such as the national strength training recommendations, is not taught in most schools in Australia 36 .
In the United Kingdom (UK), sports and exercise medicine in the undergraduate medical curriculum was proposed almost forty years ago 73  activity, low confidence in counseling, and a tendency to better recognize the importance of exercise aimed at prevention but not for disease management, which reinforces the need to promote knowledge of the benefits of PA not only for the prevention of NCDs but also for its management 78 .
Given PA's relevance for the prevention and treatment of many physical and mental diseases, it is unlikely that the attention it currently receives is sufficient to prepare medical students for their professional performance. As Jaques and Loosemore asked, "Why is PA medicine not adequately included in the undergraduate curriculum" 72 ? Impediments include lack of curricular space, time, and qualified educators [75][76][77]79  It is a fact that PA is seen as part of other topics in medical schools and can be worked on within various curricular units.
However, considering the findings of the present study and the raised discussions, it is essential that the approach be explicit and programmed in the medical curricula, not necessarily as a curricular unit, but longitudinally during the course and, ideally in conjunction with other discussions, aimed at both disease prevention and treatment. The mere presence of PA in the syllabus of mandatory curricular units can be an initial step to guarantee its adequate inclusion in medical education.

Strengths and limitations
The greatest strength of the present study is its pioneering characteristic, since this is the first study on the proposed topic One of the study limitations was not identifying curricular units that work with PA within broader topics and that do not necessarily contain the term PA in its name. Moreover, some of the accessed institutional documents were very succinct and did not allow an in-depth analysis of how PA was effectively addressed in its program.