One of the major challenges facing the United States is the high number of overweight and obese adults, along with the growing number of overweight and unfit children and youths. To improve the nation’s health, young people must move into adulthood without the burden of obesity and its associated chronic diseases. To address these issues, the American College of Sports Medicine, the Academy of Nutrition and Dietetics, and the US Department of Agriculture (USDA)/Agriculture Research Service convened an expert panel meeting in October 2012 titled “Energy Balance at a Crossroads: Translating the Science into Action.” Experts in the fields of nutrition and exercise science came together in Washington, DC, to identify the biological, lifestyle, and environmental changes that will most successfully help children and families attain and manage energy balance and tip the scale toward healthier weights. The desired outcome of this expert panel meeting was to translate the science of energy balance into practical and appropriate recommendations for training current and future professionals in nutrition, exercise/physical activity (PA), health education, and pre-K–12 teacher education. This included discussing the associated components necessary to achieve and maintain a healthy body weight. The specific goals were as follows:
- Professional training. Develop a comprehensive strategy to facilitate the integration of nutrition and PA education—emphasizing the dynamic nature of energy balance in the regulation of weight—into the training of undergraduate and graduate students in dietetics/nutrition science, exercise science/PA, and pre-K–12 teacher preparation programs as well as into the training of existing cooperative extension faculty.
- Consumer and community education. Develop best practices for integrating education on the dynamic nature of energy balance into new and currently funded nutrition and PA federal/state programs for preventing and/or reducing obesity.
The expert panel meeting was divided into three sections. The first section addressed the biological and lifestyle factors that affect energy balance. The second section addressed undergraduate and graduate educational and training issues, and the final section addressed best practices associated with educating the public including consumers and communities about the dynamic nature of energy balance. The key points addressed by each speaker are summarized in the following sections and followed by the group consensus recommendations for each goal.
EXAMINING BIOLOGICAL AND LIFESTYLE FACTORS INFLUENCING THE DYNAMIC NATURE OF ENERGY BALANCE
The concept of energy balance for regulating body weight is simple in principle. When energy expenditure exceeds energy intake, weight is lost. When energy intake exceeds energy expenditure, weight is gained. Because of the high prevalence of obesity in the United States, interventions for prevention and treatment of obesity have typically focused on reducing energy intake, increasing energy expenditure, or a combination of these strategies. Although these interventions have shown success, weight change may be less than expected and not all individuals respond to these interventions similarly (9,12). A potential factor contributing to individual variability in weight regulation, with different patterns of diet and PA, may be the type of intervention used. Dietary interventions to reduce energy intake or efforts to increase energy expenditure through PA are often treated as separate and independent approaches. For example, suggesting that a deficit of 500 kcal·d−1 from energy intake will consistently yield 1-lb weight loss per week (e.g., 3500 kcal = 1 lb) for everyone (9,11,12). This static approach to energy balance does not take into account the effect that changing energy intake has on total energy expenditure (7). By definition, energy balance is a dynamic, not static, process, in which altering one component of the energy balance paradigm can affect the physiological and biological components of the other in an unpredictable or unintended way (7,10,16) (Fig. 1). We know that body weight is regulated by several factors, including genetic, metabolic, environmental, social, and behavioral components, which can influence both sides of the energy balance equation differently, depending on the individual and the circumstances (7,12,18). This concept is important as we ascertain the contribution of dietary factors, including macronutrient composition, and PA factors, including varying modes, intensities, and quantities, to energy balance. With this new information, we can refine recommendations to improve the regulation of body weight and composition.
We now have strong scientific evidence supporting the benefits of consuming a healthy diet and being physically active for improved health and longevity, achieving or maintaining a healthy body weight, and reducing risks of chronic disease (5,19,27,28). Although the amount of daily PA required to significantly improve the health of most sedentary Americans is within reach (27), there has been little success in motivating the vast majority of people to add even this modest level of PA into their lifestyle (2). The biggest question for the new millennium may not be “what” or “how much” but simply “how” to make sustainable lifestyle changes that foster healthy body weight.
The “small changes” approach has had some success (25). This approach emphasizes small consistent changes in lifestyle to eliminate the “energy gap” that leads to weight gain. However, even this method requires individuals to find a compelling reason to sustain this behavior change in the face of competing life priorities (22). One promising approach may be to shift the focus away from the emphasis on health (e.g., appropriate diet and PA) to discussing other benefits, such as improved learning, cognition, and productivity in the workplace. Rather than aiming at self-actualization as the motivator, more basic motivators of human behaviors could be used to help individuals thrive in the modern world, such as education and employment, which provide the means for acquiring the basic elements for survival. If the reason for building recommended guidelines for diet and PA into schools was to improve classroom learning and test scores, the discussion might change. The outcome would be better educated children who are able to compete more successfully in the marketplace. Likewise, the workplace could be transformed if healthy living, derived through using science- and evidence-based PA and healthy eating practices, was an expectation of employers because it improves productivity. More research is needed on the effectiveness of using an “alignment of purpose and incentives” approach in different settings throughout society.
Finally, consumers also need to embrace and understand the role of diet and PA in managing body weight. The high prevalence of overweight and obesity in the United States has increased the importance of balancing energy (calories) consumed and energy expended to achieve and maintain a healthy weight and body composition. Numerous policy and educational efforts aim at helping consumers achieve energy balance. Still, the International Food Information Council Foundation’s 2012 Food & Health Survey consistently finds that consumers who remain largely unaware of their estimated daily energy needs and how these energy needs can be altered—and weight management improved—by changing daily PA (15,24). In the 2010 Dietary Guidelines Alliance Consumer Research (research specifically on parents), the outcomes revealed a lack of basic understanding of the term “calories” and the effect that calories (e.g., energy intake) have on weight. There was also a belief among some parents that “calories” may be the latest food and nutrition fad (4). The need to individualize communications about the numerous factors that affect energy balance is essential because each person has a unique weight management profile that is affected by many factors, including genetics, age, PA, health issues, and desired weight outcome. Although some Americans would like to maintain weight and prevent further weight gain, others would benefit from achieving successful weight loss. However, to effectively communicate energy or caloric balance, it will be imperative to examine consumer response to energy balance communications. Some messages or terminology, although widely accepted by health professionals, are not understood by consumers. A key first step in addressing consumers’ calorie confusion may be to familiarize them with their daily calorie needs. Consumers need to understand the amount of energy needed to maintain weight and how that daily calorie need is affected by the type and amount of PA as well as food and beverage choices.
ENERGY BALANCE EDUCATION: PREPARING THE NEXT GENERATION OF EDUCATORS IN NUTRITION AND DIETETICS AND EXERCISE SCIENCE
Dietetics education is a process of accruing knowledge and skills that are subsequently implemented within the field. As registered dietitian–nutritionists (RDN) grow professionally, they layer new knowledge, skills, and experience onto existing foundations. The layering effect allows dietetics students to move from the novice level in undergraduate programs to competency in the coordinated or internship programs and ultimately to proficient dietetics practitioners. Education standards, established by the Accreditation Council on Education for Nutrition and Dietetics, are in place to ensure that the proficient practitioner is ready for an entry-level position in the work force. In February 2012, new education standards were released for Didactic Programs in Nutrition and Dietetics, Internships for Nutrition and Dietetics, and Coordinated Nutrition and Dietetics Programs. Current standards do not address knowledge or skills in the areas of exercise science or PA (2012 Standards for Dietitian Education Programs, available at: http://www.eatright.org/ACEND/). In general, dietetics students are trained to work with individuals in applying the Nutrition Care Process and prescribing diet recommendations for prevention and treatment of acute and chronic diseases. To lead effective interventions that help Americans achieve and maintain healthy body weights, RDN must understand the dynamic nature of energy balance. The lack of education requirements related to the role of PA in energy balance and chronic disease prevention may limit nutrition and dietetics practitioners to only one side of the equation when working with today’s overweight and obese pediatric and adult populations.
Within the exercise science area, formal education on the energy expenditure side of the equation has focused on exercise prescription. Exercise science students are typically trained to work with people to prescribe exercise for fitness and/or sports performance, whereas others are trained in bench and laboratory sciences. Although this training has its place, much of the research and public health recommendations have shifted from exercise for fitness to PA and exercise for health and prevention of chronic disease (27,29). Exercise science educators need additional training in nutrition and in the field of PA and health at the population level. How do we prepare exercise science students to help reduce the obesity epidemic and its associated chronic diseases? This goal cannot be accomplished by having students simply take one course in nutrition or vice versa. Students need to be trained using a multidisciplinary model that includes a curriculum in exercise/PA and an understanding of nutrition and behavior sciences. This approach would enable students to better understand the factors that can prevent or reduce overweight and obesity.
These educational approaches will help the RDN and the exercise science professional work together. They will better understand the scope of practice and language used within each profession and the role each can play in helping clients. Finally, it will help them work together within schools and communities to achieve healthier lifestyles.
TRANSLATING THE DYNAMIC NATURE OF ENERGY BALANCE INTO PUBLIC AND CONSUMER EDUCATIONAL PROGRAMS FOR HEALTHY LIFESTYLES AND OBESITY PREVENTION
Cooperative Extension System positioned for a role in training
The Cooperative Extension System (CES) is a nationwide, noncredit educational network in the United States. Federal, state, and local governments provide core funding for the CES. Every state and territory has a cooperative extension state office located at its land-grant university and a network of regional or local offices. CES is an active partner of other organizations addressing state and local community interests. The CES faculty, staff, and volunteers provide practical, research-based education on food, nutrition, and health to children, youth, and adults. The Cooperative Extension is uniquely positioned to lead training for community educators. Such education could include the dynamic nature of energy balance and translation of this science into practical approaches to prevent and decrease obesity and its associated diseases. The USDA National Institute for Food and Agriculture (NIFA) is the federal partner of the CES. USDA–NIFA contributes funding to the CES and helps the CES identify and address current issues. Obesity prevention is a priority issue for NIFA. Traditionally, food and nutrition have been the primary foci of CES programs addressing obesity prevention. NIFA and its land-grant university partners have infrastructure and networks that are uniquely situated to use their three-part mission of research, education, and CES to integrate food, nutrition, and PA education into effective programs to help solve the multifaceted obesity problem (17,21). USDA is in a unique position to spearhead program leadership and partner with other government agencies to facilitate dissemination of accurate energy balance messages in public education programs including the Supplemental Nutrition Assistance Program Education and the Expanded Food and Nutrition Education Program (www.nifa.usda.gov).
Integrating dynamic energy balance into public school programs
Most (>90%) US children and youth spend approximately 7 h·d−1 in school most of the year. In 2011, schools served 35 million school lunches to students each school day (26). Schools also offer opportunities for students to be active through physical education, recess, and in-class activity breaks for PA. Unfortunately, schools have repeatedly sacrificed PA to increase academic time despite evidence of the benefits of PA in learning readiness and academic performance (29).
Because of the vast reach and potential for sustained intervention, schools are central venues for translation of energy balance science into action (8,29). This potential was recognized when the Institute of Medicine identified schools as a national focal point for obesity prevention (8). School-based controlled studies offer insights into best practices but have had limited success in reducing obesity, in part, because the intervention programs have not been sustained (1). Adoption and maintenance of lifelong healthy behaviors require ongoing opportunities in a supportive environment. Thus, schools should provide a consistent environment that is conducive to healthful eating and regular PA inside and outside the classroom. Coordinated changes in curricula, school environment, school food and health services, and after-school programs are needed to reinforce the numerous factors that affect energy balance and advance obesity prevention (20).
In this era of dwindling resources and high-stakes testing, stakeholders must be convinced of the benefits and partnerships must be formed to sustain programs. Programs must move forward on the basis of the best available evidence rather than waiting for the best possible evidence. As an example, the University of Arizona is currently conducting a successful school–community partnership. Their College of Agriculture and Life Sciences, Nutritional Sciences Department, and cooperative extension have partnered with the Pima County Health Department, YMCA, Food Bank, and local schools to deliver reinforcing “model” programs supporting PA, access to healthy food, and increased nutrition and PA knowledge (6). Feasible contributions by each partner add up to consistent opportunities for translating the science of dynamic energy balance into action in communities.
Educational efforts to prevent obesity and manage weight have focused primarily on reducing energy intake and more recently on combining reduced energy intake with increasing energy expenditure. The effect of PA alone on weight change is more limited (5). Despite these approaches, overweight and obesity are still major public health issues. Frequently, weight loss approaches advocate changes in diet without discussing appropriate PA or how the integration of these two factors will affect weight change (5,14,27). Emphasizing only one side of the energy balance equation ignores the dynamic nature of energy balance, which requires the integration of PA and nutrition. Through understanding that PA and nutrition have equal and integrated roles in weight management, educators can help people understand how each side of the equation influences the other.
A review of curricula for future health care practitioners reveals that current training does not provide the groundwork for an integrated approach that includes both nutrition and PA and the understanding of the dynamic nature of energy balance (http://www.csress.usda.gov/nea/food/pdfs/health_infocus_background_el.pdf). Exercise science training does not integrate nutrition, and nutrition and dietetics training typically lacks exercise science and PA education in its training competencies. Moreover, additional inclusion of behavioral theory in these disciplines would be beneficial. These disconnected sets of disciplines are less effective in isolation when confronting the obesity epidemic.
CALL TO ACTION/OPPORTUNITY
Nutrition and exercise science professionals need to effectively communicate the importance of both sides of the energy balance equation and its dynamic nature, placing emphasis on both energy intake and expenditure and the effect one has upon the other (3,7,19,21,23). This message should be consistent yet tailored to the specific interests of each audience. The messages need to be science- and evidence-based and easily understood. Incorporating behavioral psychology principles can help engage and motivate people to effect sustainable change in energy intake and expenditure. For example, school administrators may be motivated by opportunities to improve the learning and test taking skills of their students, whereas health care providers may respond to potential improvements in cognition and other health benefits, and business professionals may respond to the potential for improved productivity of workers.
Training Future Educators and Health Professionals
Higher education needs to integrate nutrition and PA using an understanding of the dynamic nature of energy balance for undergraduate and graduate students in dietetics/nutrition, exercise science, health and wellness, and pre-K–12 preparation programs.
- Integrate a multidisciplinary approach to the training of exercise science/PA professionals and RDN in the dynamic nature of energy balance. This approach integrates PA competencies into the training of RDN and nutrition knowledge and skills into the training of exercise science/PA professionals. Both groups need training in the behavioral sciences. As a first step, the Academy of Nutrition and Dietetics and the American College of Sports Medicine are currently considering the development of a joint certificate program addressing these three areas.
- Develop competencies for pre-K–12 school teachers and physical education teachers using the dynamic energy balance approach. This outcome would allow teachers to be champions for integration of nutrition, PA, and behavioral education focused on reducing obesity. Thus, teachers would have the knowledge and skills to help their students make healthy choices.
- Develop comprehensive nutrition education core standards, both in nutrition and PA, for K–12 schools that include a clear integration of the dynamic energy balance approach. The USDA Food and Nutrition Service and the Institute of Medicine are considering benefits of national nutrition education curriculum standards for elementary and secondary school children (13). This is an opportunity to widen the scope of such standards to include dynamic energy balance. Integrating similar standards into the PE curriculum would provide children with the knowledge and skills to facilitate lifetime PA and also be advantageous to ensure cross-curriculum promotion of the importance of both healthy eating and PA.
- Encourage the development of comprehensive curricula emphasizing the dynamic nature of energy balance and providing experiential learning opportunities for students and current health professionals. This could be done through the USDA Higher Education Challenge Grant program, US Department of Education grants, university programs, or through professional organizations producing educational materials that can be used in training future health professionals.
Consumer and Community Education Programs
Developing a strategy to incorporate more realistic energy balance messages into education programs for consumers and communities is vital for achieving and maintaining healthy weight and body composition among the population. It is also critical that we better understand how this energy balance concept can be shared with the public. Figure 2 shows descriptions of three school-based nutrition and PA programs that are already successfully working toward this goal.
- Determine what energy balance messages work most effectively with consumers. Research is needed to help the professional better communicate clear and realistic energy balance messages to consumers. These messages need to help consumers better understand the effect of nutrition and PA on their health and weight.
- Communicate the message of dynamic energy balance to a wider audience. Once messages are identified, collaborative effort will facilitate the reach of the messages to a wider audience. Government and public health agencies and schools, community agencies, businesses, and medical, health, and fitness facilities can distribute these educational messages to diverse sectors within communities. USDA is in a unique position to spearhead program leadership and partnership with other government agencies and land-grant universities to facilitate dissemination of integrated energy balance messages in public education programs including the Supplemental Nutrition Assistance Program Education and Expanded Food and Nutrition Education Program. Promoting collaboration among key professional networks would help promote accurate and realistic messages about energy balance to the public.
- Facilitate partnerships with schools and local public health professionals, organizations, and programs. Pre-K–12 schools provide an excellent vehicle for the delivery and practice of energy balance. From the meals, snacks, and vending machines to the physical education, recess, and sports programs, there are opportunities to promote integrated nutrition and PA. Enhancing these efforts through community partnership programs such as school and community gardens, walking school buses, community walking programs, and before- or after-school programs expands opportunities to access healthy food and PA. Programs like Fuel Up to Play 60 and Energy Balance 4 Kids with Play are excellent examples of the integration of daily PA and movement in schools and improved access to healthy food.
- Map integrated nutrition and PA programs currently being provided. A mapping resource would allow individuals to quickly find and select integrated nutrition and PA programs in which to participate or to bring to their schools, organizations, churches, or communities. Many government, corporate, and foundation nutrition and PA programs are now available but not widely marketed. Mapping would reduce duplication of programs and allow providers to identify “nutrition and PA educational program deserts.” This mapping could be done similarly to the way the USDA Economic Research Service currently maps food deserts.
We thank Dr. Margaret Bouvier of Meg Bouvier Medical Writing for her help in writing this manuscript.
Corporate speakers were sponsored by their respective organizations (K.B.M. S.E.A.S. L.G.G. and A.M.K.) and presented programs, research, or positions of their organizations. Other speakers (L.H. J.M.K. and J.C.P.) had travel costs and honorarium provided by the Energy Balance Work Group through the American College of Sports Medicine Foundation. M.M.M. received travel costs provided by the Energy Balance Work Group through the ACSM. J.C.P. is on the advisory board of Arkansas Biomedical Sciences Institute and is retired from the Procter and Gamble company but no longer receives compensation. Other authors have no conflict of interests.
The following institutions are conveners, sponsors, and speakers: American College of Sports Medicine (convener/sponsor), Academy of Nutrition and Dietetics (convener/sponsor), US Department of Agriculture/Agriculture Research Service (convener/sponsor) and National Institute of Food and Agriculture, International Food and Nutrition Council (speaker), International Life Sciences Institute North America (sponsor), National Dairy Council/Dairy Research Institute (sponsor/speaker), Quaker/Pepsi (sponsor), National Cattlemen’s/Beef Association (sponsor), American Council on Exercise (sponsor), Centers for Disease Control and Prevention (speaker), Healthy Weight Commitment Foundation (speaker), and Sports, Cardiovascular, and Wellness Nutrition Dietetic Practice Group (sponsor).
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