American Journal of Lifestyle Medicine

Lifestyle interventions have evolved from proof-of-concept pilot studies to efficacy and effectiveness studies and have now moved toward translation and dissemination studies because of their demonstrated ability to improve cardiovascular disease (CVD) outcomes. When combined with diet, they also have demonstrated the ability to normalize blood glucose levels and help to regulate weight. This review highlights the converging lines of evidence that led to lifestyle physical activity interventions, beginning with early epidemiology studies, and provides evidence for the efficacy and effectiveness of lifestyle interventions. However, if lifestyle interventions are to play a role in preventing CVD and improving CVD outcomes, their use must be more widespread. This will require translational and dissemination research to understand how to move into real-world settings. Successful examples of translational studies will be highlighted, and issues related to theoretical and practical issues as well as capacity building will be discussed. Building bridges between research and practice must be done if lifestyle interventions are to deliver on their public health promise.

The epidemiologic transition describes changing patterns of population age distributions, mortality, fertility, life expectancy, and causes of death. A number of critiques of the theory have revealed limitations, including an insufficient account of the role of poverty in determining disease risk and mortality, a failure to distinguish adequately the risk of dying from a given cause or set of causes from the relative contributions of various causes of death to overall mortality, and oversimplification of the transition patterns, which do not fit neatly into either historical periods or geographic locations. Recent developments in epidemiologic methods reveal other limitations. A life course perspective prompts examination of changes in causal pathways across the life span when considering shifts in the age distribution of a population, as described by the epidemiologic transition theory. The ecological model assumes multiple levels of determinants acting in complex and interrelated ways, with higher level determinants exhibiting emergent properties. Development, testing, and implementation of innovative approaches to reduce the risks associated with the sedentary lifestyle and hypernutrition in developed countries should not overshadow the continuing threat from infectious diseases, especially resistant strains or newly encountered agents. Interventions must fit populations and the threats to health they experience while anticipating changes that will emerge with success in some areas. This will require new ways of thinking that go beyond the epidemiologic transition theory.

The 20th century in the United States has experienced a dramatic increase in life expectancy among adult men and women, an increase unprecedented in the history of this country. As a result, the pattern of disease and conditions most responsible for death in the United States shifted during the past century from infectious diseases and unintentional injuries to the current array of the leading causes of mortality dominated by the chronic diseases. During this same period, daily lifestyle dramatically shifted from a life full of active living to one of inactivity. The argument has been made that in the case of human beings, there has been little or no change in our genotype within the past 50 years. However, there have been major changes documented in the living environment among economically developed societies during this same time period. Through the collection of epidemiologic, clinical, and experimental findings, evidence suggests that physical inactivity is associated with the onset of chronic diseases of our day. Trends in physical inactivity, evident through the monitoring of transport, recreation, sport, and purposeful activity, have demonstrated that the current lifestyle of the 21st century has contributed substantially to the chronic disease burden in the United States and elsewhere. By addressing the domains that influence physical activity behaviors including the environment (both physical and social/cultural), health systems access, and behavioral correlates of physical activity and inactivity, the current chronic disease crisis potentially can be addressed.

Epidemiologic studies have consistently identified a strong inverse association between coronary heart disease (CHD) and regular, predominantly moderate-intensity physical activity and cardiorespiratory fitness. Supporting evidence of causative relationships has been provided by aerobic exercise training studies in both animals and humans. This research demonstrated multiple plausible cardioprotective biological mechanisms. These include direct antiatherosclerotic effects by improving artery endothelial function and reducing inflammation and indirectly via modification of other risk factor components of the metabolic syndrome, by reducing risk of a coronary thrombotic occlusion (antithrombotic effects), by decreasing myocardial oxygen demands and increasing its vascular supply (anti-ischemic effects), and by improving cardiomyocyte electrical stability and autonomic nervous system adaptations (antiarrhythmic effects). Although much additional research is needed to better define and establish optimal dose-response relationships, clearly these pleotropic effects strongly suggest that aerobic exercise can attenuate the risk of CHD at all stages of the underlying atherothrombotic process.

The development of the understanding of the underlying causes of coronary heart disease has undergone several stages. Ecological studies, such as the Seven Countries' Study, showed a possible relationship between mortality in coronary heart disease and intake of saturated fats. The investigated area with the lowest rates of cardiovascular disease was the island of Crete, Greece. A discussion soon started to evolve around the Mediterranean diet, which at the time consisted mainly of foods of vegetable origin, olive oil, and cereals of unrefined nature. Several clinical trials have been undertaken since then, including the Lyon Heart Diet Study, in which it was clearly shown that both mortality and morbidity in coronary heart disease were substantially lowered by Mediterranean food compared with controls. Dean Ornish proved that an extreme regimen actually could reduce already existing sclerotic plaques, while the Women's Health Initiative study showed that a more modest diet change did not cause the intended reduction in heart disease in middle-aged women. Another prospective study of a similar age group of women showed that a diet with a low glycemic load provided a good reduction in coronary heart disease. Multiple studies of different components of food have shown no positive result, pointing at the whole diet rather than its components of nutrients as being of importance. Today, the experts agree on the optimal diet to prevent not only heart disease but also cancer forms and other chronic disease such as type 2 diabetes mellitus. This diet consists of a lot of fruit and vegetables, lots of fish, less salt and sugar, more unrefined cereals, beans, and nuts. Going from a general notion of Mediterranean food to testing that food in clinical settings and testing nutrients as preventative agents, it can be concluded that a generally healthy lifestyle, including a healthy diet, appropriate amounts of physical activity, good sleep, and less stress, is the way to a heart-healthy life.

There is growing consensus that systemic inflammation is at the heart of cardiovascular disease (CVD). Inflammation is a key feature of the immune system, functioning to defend tissue integrity and function. However, chronic stimulation of inflammatory mediators leads to lasting vascular reactivity, insulin resistance, hyperlipidemia, and, subsequently, chronic disease. Dietary practices to minimize inflammatory stimuli and CVD risk include regular intakes of fatty fish rich in the eicosapentaenoic and docosahexaenoic acids that compete with the more pervasive membrane fatty acid, arachidonic acid, disrupting the metabolic cascades that stimulate inflammation. Another effective dietary strategy is to consume less arachidonic acid by reducing beef, poultry, fish, and eggs from the diet (eg, adopting a vegetarian-like diet). Because oxidative stress plays a prominent role in immune system activation, regular ingestion of ample amounts of fruits and vegetables (8+ servings/d) rich in antioxidant compounds, the polyphenols, carotenoids, and vitamin C (eg, citrus, tomatoes, berries, carrots, and greens), lowers inflammatory mediators and risk for chronic disease. Whole grains, legumes, and nuts have also been demonstrated in clinical trials to effectively reduce inflammatory mediators and risk for CVD. As proclaimed in antiquity, “let food be thy medicine and medicine be thy food.”

Physical inactivity is an established risk factor for cardiovascular diseases. However, although physical activity is recommended as a component of healthy lifestyle, the amount (intensity, duration, and frequency) of physical activity required to protect against coronary heart disease (CHD) and cerebrovascular disease (ie, stroke) is unclear. In general, there is a graded inverse association of physical activity with CHD and total cardiovascular disease (the combination of CHD and stroke). The patterns of association between physical activity dose and stroke are less clear; individual studies suggest a threshold effect for benefits, whereas meta-analytic studies report a graded inverse association. Despite known differences in physical activity behaviors between men and women, the patterns of association between dose of activity and cardiovascular diseases are similar by gender. Observational studies of walking behaviors and one recent clinical trial suggest that lower “doses” of physical activity are associated with a lower risk of cardiovascular disease. Thus, with very few specific cautions, there is enough evidence to recommend to healthy adults that any activity is beneficial and that more activity is even better.

The purpose of this article is to describe a pedometer-based physical activity intervention (and the research that has been conducted on this program) to provide insight into workable strategies focused on promoting lifestyle physical activity. The First Step Program (FSP) is a facilitated theory-based behavior modification program, originally developed for individuals with type 2 diabetes, that capitalizes on the unique properties of a pedometer to serve as a stimulus for walking and an instrument for individual goal setting, self-monitoring, and feedback. Formative evaluation revealed that participants were highly enthusiastic about the program, and pilot testing demonstrated an immediate and dramatic increase in walking behavior (by approximately 3700 steps/d or 34 minutes of walking per day). A randomized and controlled evaluation produced similar results, as have head-to-head comparisons of participant outcomes produced by professional versus peer delivery, and adaptations of the program to work site and community-based delivery. The effectiveness of the FSP can be explained by a thoughtful consideration of pedometer characteristics, program features, and the people who participate. Sustained delivery is contingent on funding sources and administrative structures that support formalized implementation.

Sleep disturbances are a common problem, with chronic insomnia occurring in 10% of the general adult population and obstructive sleep apnea present in 4% and 2% of middle-aged men and women, respectively. In addition, Americans are sleeping fewer hours per night than they did 20 years ago. There is now increasing evidence that reductions and increases in sleep duration, as well as various sleep disorders, including obstructive sleep apnea and insomnia, may be causal factors in the development of cardiovascular disease. Some of the evidence linking disturbances of sleep with cardiovascular disease is described in this review.

In recent years, a growing body of evidence has linked positive emotional health with lower cardiovascular morbidity and mortality, independent of negative emotion. Several potential mechanisms have been posited to account for these associations, including improved health behavior, direct physiological benefits, and enhanced resistance to and recovery from stress among individuals with high versus low positive emotional resources. Links between positive emotion and health have implications for targeted interventions, but no empirical investigations to date have tested the impact of efforts to enhance positive emotion on cardiovascular risk. Nevertheless, some existing data point to the potential value of strategies to increase emotional resources for individuals' functional health and capacity to manage stress.

Culture plays an integral role in people's food choices and lifestyle decisions. Health care messages may conflict with cultural beliefs for many immigrant, minority, and low-income populations. The multiple ways that culture can positively and negatively affect disease risk must be used in the development of culturally tailored messages or interventions. Only through the creation of interventions that are meaningful and culturally relevant can successful behavior stability or change occur. The recognition of current health-promoting factors is important to develop rapport and credibility with individuals and population groups to reduce the risk of cardiovascular disease and other lifestyle-based chronic diseases for optimal health.