Mental health has been described as the emotional and spiritual resilience that enables people to enjoy life and to survive pain, disappointment, and sadness. It is fundamental to health and well-being and is more than the absence of symptoms of mental illness. Mental illnesses are health conditions that are characterized by alterations in thinking, mood, or behavior associated with distress and/or impaired functioning. Mental health and mental illness should be considered distinct. An individual may have a diagnosis of a mental illness, such as schizophrenia, yet still attain positive mental health. Mental health problems, such as subclinical levels of depression, can affect individuals without necessarily becoming a diagnosed mental illness. Consequently, mental health concerns everyone, and strategies to promote mental health should be implemented for the benefit of all. No single factor causes poor mental health or mental illness. Rather, these are influenced by a range and combination of factors such as genetic inheritance, biochemical and psychological factors, life events, and socioeconomic circumstances. Similarly, when mental health improves, it is likely that a combination of factors is at work.
The physical health benefits of exercise and physical activity (PA) are well established. PA, as a general term, refers to any movement of the body that results in energy expenditure above that of resting level. Exercise refers to a subset of PA in which the activity is structured and often supervised and undertaken with the aim of maintaining or improving physical fitness or health. Research is rapidly increasing concerning the impact of both on mental health. A focus on this relationship is very relevant as mental health outcomes may motivate people to stay physically active while also having a potentially positive impact on mental health. Without regular participation, both mental and physical benefits will not accrue.
This entry describes four main functions of PA in impacting mental health. First, PA may prevent mental health problems. Second, exercise has been examined as a treatment or therapy for existing mental illness. Third, exercise may improve the quality of life (QOL) for people with mental illness. Fourth, exercise and PA can improve the mental health of the general public in a broad number of ways.
There is some evidence that participation in PA prevents mental health problems from occurring at a later time. Given our aging society, senile dementia and Alzheimer’s disease represent significant public health burdens. Some evidence suggests a reduced risk of dementia for individuals who are physically active. More extensive evidence is available regarding depression. In 2010, the World Health Organization predicted that depression would be second only to ischemic heart disease in global overall disease burden by the year 2020. This prediction is alarming when considering depression’s detriment to physical and mental health. Depression is commonly associated with high morbidity and mortality rates; increased risk of suicide; major suffering; and a decrease in physical, cognitive, and social functioning. To look at the role PA has on the prevention of depression, epidemiological, prospective longitudinal studies are required to identify a temporal relationship. Such studies involve large numbers of people and measure levels of PA and depression at two or more time periods. For example, a study conducted by William Strawbridge and colleagues in California collected measures of PA and depression from 1,947 community-dwelling adults ages 50 to 94 years at baseline in 1994 and after 5 years of follow-up. After excluding individuals with depression in 1994, an increase in PA was associated with a significant (20%) reduction in the likelihood of being depressed in 1999. Perhaps this finding could be explained by bias in some way—for example, individuals with a physical disability may have both a higher risk of depression and lower levels of PA. Most studies like this one, however, continue to demonstrate a relationship between PA and a decreased risk of depression while accounting for a wide range of possible confounding factors, such as disability, smoking, alcohol, and social status, in the statistical modeling. Overall, these types of studies suggest PA has a protective effect against developing depression.
Exercise might be used as a therapeutic strategy to alleviate mental health problems or mental illness. As with the preventive function, the most compelling evidence comes from studies in the area of clinical depression. As depression is the most common mental health problem, it has received more attention by researchers than other conditions. Meta-analyses quantify results from a number of studies and allow statistical techniques to be used as a means of analysis. The basis of a meta-analysis is the effect size (ES), which transforms differences between an experimental and control group to a common metric. As a guideline, ES, usually determined through the calculation of differences between an exercise and control group or from preto post-exercise intervention, of ≥.2, ≥.5, and ≥.8, is generally described as reflecting a small, moderate, and large effect, respectively. In one meta-analysis of 28 studies examining exercise and depression, comparing exercise with no treatment or a control intervention, the ES was –0.67 indicating a moderate clinical effect. However, when only the four methodologically strongest trials were analyzed, the ES was reduced and was small at –0.31. Notably, this ES is comparable to those seen in meta-analyses of the effects of medication on depression. These findings suggest exercise might be an additional consideration for treatment for those who are interested in trying it. Researchers have started to examine how exercise might be an adjunctive treatment for other illnesses such as bipolar disorder, anxiety, and drug dependence.
Physical Activity for Quality of Life and Coping With Mental Illness
For people with severe and enduring mental health problems, improvement in QOL tends to enhance the individuals’ ability to cope with and manage their disorder. In this case, exercise might be useful in improving the mental health of individuals with a mental illness. A good example is schizophrenia—a serious mental illness that is characterized by psychotic symptoms (e.g., hallucinations, delusions), disorganized speech and behavior, negative symptoms (e.g., apathy, blunted or flattened affect), and neurocognitive and social cognitive deficits. Epidemiological surveys demonstrate an excess of physical morbidity and premature mortality in individuals with schizophrenia with the largest causes of death being related to cardiovascular disease, obesity, and diabetes. Potential causes of this excess mortality and morbidity are varied but can be broadly categorized in terms of changes in treatment (metabolic side effects of medication); greater prevalence of engagement in unhealthy behaviors such as smoking, physical inactivity, and poor nutritional habits; and limited access to health care. Consequently, PA promotion is well warranted in this population irrespective of mental health gains. One meta-analysis suggests small effects in terms of improvements in some of the negative symptoms of schizophrenia such as depression, low self-esteem, and social withdrawal. There is less evidence that exercise may be a useful coping strategy for dealing with positive symptoms such as auditory hallucinations. There are limitations to this research literature, but the evidence suggests exercise interventions are feasible in this population and can have healthful effects on both the physical and mental health of individuals with schizophrenia.
Mental Health Promotion for All
There are many components of mental health such as self-esteem, cognitive functioning, stress, and sleep. Although research has been conducted on all of these topics, its extent and degree of methodological rigor vary. The majority of existing research examining exercise and mental health is included in this category. Self-esteem has received much attention because many consider it a central aspect of mental health, as it reflects the overall evaluation or appraisal of one’s own worth. In a meta-analysis, there was a small relationship between exercise and self-esteem (+0.23). One well-accepted approach to self-esteem considers the construct to be multidimensional and hierarchical in nature. That is, self-esteem can be broken down to many constituent parts comprising an extensive number of life domains. For example, one’s self-esteem could be based on how well he or she performs at work, in relationships with others, or how one looks and feels physically. Theoretically, one might expect exercise to have a stronger relationship with components of self-esteem related to the physical self. Research confirms a stronger effect is seen when there are significant changes in physical fitness, for example, and this can extend to more generalized improvements in self-esteem. Overall, there is evidence that exercise can change people’s perceptions of their physical self and identity in a positive way.
How Does Exercise Benefit Mental Health?
Understanding how exercise improves mental health may lead to the development of exercise prescriptions that more effectively and reliably improve the mental health of individuals. Researchers have investigated a range of mechanisms that can be broadly described as being biochemical, physiological, or psychosocial in nature. A commonly suggested biochemical mechanism is that endorphins (endogenous opioid peptides) are responsible for euphoria or other changes in mood during or after acute exercise. While such a mechanism is plausible, there is still no compelling evidence to support such claims. Changes in fitness, a physiological mechanism, may explain improvements in mental health. However, some studies demonstrate mental health benefits even when there are no changes in fitness. Psychosocial mechanisms have also been explored, including how exercise may enhance perceptions of mastery or competence, or provide opportunities for distraction and/or social interaction. Current consensus is that there is unlikely to be one central mechanism that explains mental health benefits for all people. Because mental health is influenced by many factors, it is just as likely that many factors positively influence mental health and that exercise could be helpful through a number of pathways. Several mechanisms most likely operate in concert, with the precise combination being highly individual-specific and varying through exercise characteristics such as intensity and type, preferences of the individual, and even when and where the exercise takes place. Current guidelines for PA aimed at adults (e.g., accumulating 150 minutes of moderate-to-vigorous physical activity [MVPA] per week) are supported in terms of their potential for enhancing mental health.
The field of exercise and mental health is a rapidly growing focus for researchers and practitioners. As with most fields of study, more research is required—particularly, rigorously designed experimental studies comparing the effects of exercise to other therapeutic approaches. Furthermore, there is also scope for exploring issues such as dose– response (e.g., how the type, intensity, frequency, and duration of exercise is related to mental health outcomes), participant characteristics (e.g., who responds most positively to a “dose” of exercise), and the mechanisms that explain mental health change. Because PA is an effective method for improving important aspects of physical health, the promotion of PA for mental health can be seen as a win–win situation—the physical health benefits are indisputable, and evidence suggests that there can be important mental health benefits as well.
- Gorczynski, P., & Faulkner, G. (2010). Exercise therapy for schizophrenia. Cochrane Database Systematic Reviews, 5, Mental Health and Physical Activity. Retrieved from http://www.journals.elsevier.com/mental-health-andphysical-activity
- Rimer, J., Dwan, K., Lawlor, D. A., Greig, C. A., McMurdo, M., Morley, W., et al. (2012). Exercise for depression. Cochrane Database Systematic Reviews, 7,
- Spence, J. C., McGannon, K. R., & Poon, P. (2005). The effect of exercise on global self-esteem: A quantitative review. Journal of Sport & Exercise Psychology, 27(3), 311–334.
- Strawbridge, W. J., Deleger, S., Roberts, R. E., & Kaplan, G. A. (2002). Physical activity reduces the risk of subsequent depression for older adults. American Journal of Epidemiology, 156(4), 328–334.