How Exercise Can Help With the Healing of Depression - Research Paper Example

Theories on and Evidence of Relationships among Physical Activity, Exercise, and Depression November 22, Psychology 480 – Senior Project National University Abstract Table of contents List of Tables List of Illustrations Background of the Study Depression is a mental health condition that is characterized with low moods (e.g. feeling unhappy, hopeless, and restless) and loss of interest in normal daily functions and activities (Bentall, 2006). Dinas, Koutedakis, and Flouris (2010) stated that around 340 million people have depression all over the world. Carek, Laibstain, and Carek (2011) noted that depression is one of the most common psychiatric conditions because it affects millions of people in the United States. The Centers for Disease Control and Prevention (CDC) (2011) reported that the Morbidity and Mortality Weekly Report (MMWR) article, CDC: Current Depression among Adults: United States, 2006 and 2008, showed the results of the Behavioral Risk Factor Surveillance Survey, which estimated the occurrence of major and other forms of depression in the U.S. This survey showed that 9.1% of the surveyed 235,067 adults had current depression, while 4.1% showed symptoms of major depression. Because of this incidence rate, depression can be described as the common cold of psychiatry. The Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV) from the American Psychiatric Association (APA) (1994) states that depression, considered as a mood disorder, is a spectrum of negative mental health state that can span mild, moderate, and serious episodes of melancholy and may become the more severe and persistent kind in time, called Major Depressive Disorder (p. 317). Major Depression Disorder happens when a person has one or more Major Depressive Episodes (APA, 1994, p. 339). People are diagnosed with a Major Depressive Episode if they exhibit five or more of the following symptoms for at least two weeks, most of the day, or almost every day (APA, 1994, p. 320). These symptoms are: (1) having a depressed mood (e.g. feeling sad or empty), (2) lower or no interest or pleasure in all or many activities, (3) significant weight loss even when not dieting or weight gain, or decrease or increase in appetite, (4) insomnia or greater desire to sleep, (5) restlessness or slower behavior based on the assessment of others who have been with the patient many times, (6) fatigue, (7) feelings of being worthless or guilt, (8) lower ability in making decisions, thinking, or concentrating, and (9) having thoughts about suicide or death or conducting a suicide attempt (APA, 1994, p. 327). These symptoms produce clinically considerable distress or debilitation in social, occupational, or other vital areas of functioning (APA, 1994, p. 327). This paper, when referring to depression, includes Major Depression Disorder and Major Depressive Episodes. The most severe effect of a Major Depressive Episode is suicide or attempted suicide. Suicide risk is quite high for people with psychotic characteristics, a record of earlier suicide attempts, a family history of completed suicides, or coexisting substance use (APA, 1994, p. 323). Hawton et al. (2013) noted that, according to 1993 and 2003 studies, nine out of ten people who committed suicide had a psychiatric disorder at the time of their deaths and that autopsy studies in 1986 to 2001 showed that depression is the most prevalent of these disorders (p. 18). A Major Depressive Episode might also increase premature death rates from general medical and psychiatric conditions (APA, 1994, p. 323). Hawton et al. (2013) conducted a systematic review of international literature and learned that these factors enhance suicide risks among those who are diagnosed as having Major Depression Disorder and Major Depressive Episodes: being male, having a family history of psychiatric disorders, previous suicide attempts, more severe depression, hopelessness, co-morbid disorders (e.g. anxiety), and drug and alcohol abuses. Depression and being sick with other illnesses can increase morbidity and mortality rates (CDC, 2011). Depression can be treated through medication and other treatment and therapy options. Antidepressant medications include selective serotonin reuptake inhibitors (SSRIs), serotonin and norepinephrine reuptake inhibitors (SNRIs), norepinephrine and dopamine reuptake inhibitors (NDRIs), atypical antidepressants, tricyclic antidepressants, monoamine oxidase inhibitors (MAOIs), and other medications. SSRIs are the most prevalently used for treating depression because of their efficiency and tolerability (Walker, 2013, p. 313). Besides medication, psychotherapy is another treatment option for depression. Psychotherapy is also called talk therapy because it involves talking about depression with a mental health care practitioner. Several randomized controlled trials (RCTs) showed that psychotherapy has moderate to large effects on treating depressive orders (Barth et al., 2013; Cuipers et al., 2013), although relapse rate after two years is somewhat high, although lower when compared to non-psychotherapeutic treatments (Steinert et al., 2014). Another common treatment that is used for treating mild depression is cognitive behavior therapy (CBT). This includes the patient meeting with a psychotherapist for counseling sessions. In these sessions, a therapist will guide the patient in positive thinking patterns that will help them see the big picture (Carter et al., 2013). Patients with severe cases of depression are often given medication as part of their treatment. Another treatment that is used in people with a severe case of depression is giving them electromagnetic therapy (ETC). This treatment is used when other treatments have failed. ETC involves passing electrical currents to the brain. Around a third of patients do not positively respond to many current therapies and medicine for depression, while relapse to depression can be high, however, which emphasizes the need for alternative and complementary options (Danielsson et al., 2014, p. 168; Keitner & Mansfield, 2012; Singh & Fiatarone Singh, 2000). Increases in physical activity, which includes exercise, has received considerable attention from researchers and physicians because several systematic reviews indicated that it can have a small to large impact on treating the symptoms of depression (Dinas et al., 2011) or curing depression itself (Brosse et al., 2002; Carek et al., 2011; Rot, Collins, & Fitterling, 2009; Ströhle, 1996). Physical activity, based on some studies, is believed to be beneficial to health, while its absence may lead to different kinds of illnesses, including mental disorders (Carless, 2008; Ströhle, 1996). Physical activity refers to any kind of bodily movement that skeletal muscles perform and which uses up energy. Physical activity normally includes the categories of occupational physical work, sports activities, household work, and exercise, among other tasks that require energy expenditure. Exercise is different from ordinary physical activity because it is a planned structure for repetitive sets of physical activities that has goals of improving or maintaining physical fitness. Physical activity is an important option in treating depression because it can respond to the social, emotional, and cognitive dimensions of depression. Statement of the Problem The relationship between physical activity, exercise, and depression has been the subject of a number of psychological and neurological studies, as some clinical human and animal studies showed that increasing physical activity or engaging in exercise can help prevent or treat depression disorders (Martin, & Wade, 2000, p. 302; Ströhle, 1996, p. 777). The exact mechanisms of how physical activity and exercise treat depression are not yet fully known, because researchers have not determined the ethiopathology of depression up to now (Lanni et al., 2009, p. 2986). The fundamental causes of depression remain unknown, aside from the determination of risk factors. Some studies have only conjectured on the possible causes of these beneficial effects of physical activity on depression. Depression is a serious illness that cannot be overlooked because it can lead to a host of other physical and psychological illnesses that increase the morbidity and mortality for people, particularly who already have co-occurring physical diseases, such as cardiovascular diseases, and mental disorders. It is important to know more about the effectiveness of physical activity and exercise in curing depression because it can offer a lasting, efficient treatment option. It is also essential to determine how they work in curing depression to further improve their components. My research questions are: (RQ1) Will an increase in physical activity cure depression? (RQ2) Does exercise help treat depression? (RQ3) How does physical activity cure depression? Definition of Terms Abnormal: Different from what is considered as average by a field or discipline. Abuse: Misusing something or someone in any shape or form. Antidepressants: Medications that helps a depressed person feel better. Assuage: to relieve or heal. Attribution: Making a judgment on the cause of an outcome. Cognitive: To know or to remember something. Cognitive behavioral therapy: Guidance from a professional to think positive. Depression: Is an emotional state of mind that causes a person to have negative thoughts. Disorder: Being irregular or different than what is considered normal. DSM: Diagnostic and statistical manual for psychiatry that defines specific mental disorders. Electromagnetic therapy (ECT): Use of electric current that stimulates the brain. Exercise: Different from ordinary physical activity because it is a planned structure for repetitive sets of physical activities that has goals of improving or maintaining physical fitness. Fatigue: Feeling very tired. Genes: DNA inherited by a family member. Hopelessness: Having no courage in life. Hormone: The body’s chemical messenger. Insomnia: Being unable to sleep. Low self-esteem: A low or negative evaluation or outlook of one self. Mastery: Sense of self-control over one’s moods and activities. Mood: A state of mind. Neurotransmitter: Brain chemicals that inform one another throughout the brain and body. Physical activity: Any kind of bodily movement that skeletal muscles perform and which uses up energy. Psychiatry: A practice that deals with the mind and thoughts of a person. Psychiatric condition: A mental illness. Psychology: The study of a thinking process and conduct. Psychotherapist: A person who specializes with human thoughts and behavior. Stress: A state of mental or emotional strain due to difficult circumstances in life. Wellbeing: Being and feeling satisfied in every aspect in life. Limitations of the Study The study is limited to depression itself, though it includes mild to severe depression. It does not include other mental illnesses, although some studies included related diseases in studying the effects of physical activity and exercise on them. In addition, the study is a secondary research that explores the theories underlying the relationship between physical activity and exercise. It summarizes and analyzes the results of past clinical findings and does not conduct new experimental studies. Theoretical Framework Physical activity has social, emotional, psychological, and cognitive dimensions which can explain why and how it may relieve depressive symptoms or cure depression (Eyre & Baune, 2012; Keitner & Mansfield, 2012). Cognitive and physiological theories can be used to understand how physical activity affects people with depression. Self-schema theory is a relevant theory because depression is considered as treatable through psychotherapy and cognitive behavioral therapies and self-schema theory can facilitate the involvement of patients in curing their illnesses through improving how they see themselves (Barth et al., 2013; Cuipers et al., 2013). Markus (1977) defined self-schemas as “cognitive generalizations about the self derived from past experience that organize and guide the processing of self-related information contained in the individual’s social experiences” (p. 64). Self-schemas are specific to domains wherein they stand for the attributes and abilities of people for particular domains (Strachan & Whaley, 2013, p. 213). Self-schemas influence decision-making and behaviors through affecting how people encode, evaluate, and retrieve domain-specific information (Strachan & Whaley, 2013, p. 213). Ennigkeit and Hänsel (2014) learned from their study of participants with or without exercise self-schemas that those with exercise self-schemas reacted to positive feedback and that their motivation could be coming from their self-enhancement motives. Physical activity and exercise may improve self-schema, when people develop more positive schemas of themselves that can treat depressive symptoms. Besides self-schema theory, physiological theories can also help understand how physical activity treats depression because clinical animal studies and neurological findings from brain imaging studies are improving the knowledge on how physical activity changes the brain. The first theory is the monoamine hypothesis. This hypothesis has several variants. Monoamine theories believe that depression is connected to diminished levels of essentially available monoamines, normally either the catecholamine, noradrenaline (norepinephrine in the U.S.), or the indoleamine, serotonin (called also as 5-hydroxytryptamine, 5-HT) (Mulinari, 2012, p. 366). See Figure 1 for relationships among noradrenaline, serotonin, dopamine, and some behaviors. Figure 1: Relationships among Noradrenaline, Serotonin, Dopamine, and Some Behaviors Source: Lanni et al. (2009, p. 2988) The catecholamine description of the monoamine theory became popular after the 1965 publication of American psychiatrist Joseph Schildkraut. He conjectured that emotional states may come from changes in brain catecholamine levels, chiefly noradrenaline levels (Schildkraut, 1965). British psychiatrist Alec Coppen (1967) responded that it is serotonin that is most implicated in the pathophysiology of depression. Since catecholamines and indoleamines are monoamines, their models were called as the monoamine theories of depression (Mulinari, 2012, p. 366). These psychiatrists admitted, nevertheless, that their theories cannot fully grasp the complexity of the neurological aspects of depression (Mulinari, 2012, p. 370). A new theory may also help explain how exercise benefits people with depression, the hippocampal neurogenesis theory. Individuals with chronic depression have shown changes in hippocampal brain regions. Sawyer et al. (2012) examined hippocampal changes for depressed and non-depressed patients who are 60 years old and above. Using Magnetic Resonance Imaging (MRI) conducted every two years, findings showed a decrease in the right part of the hippocampus for four years among patients with depression (Sawyer et al., 2012). They hypothesized that this effect may be explained through the glucocorticoid cascade hypothesis. This hypothesis states that some depressed people have “high-circulating levels of glucocorticoids, which can lead to neuronal death and inhibit neurogenesis in the hippocampus” (Sapolsky, 1996). Furthermore, an animal research showed that higher levels of glucocorticoids elevate amyloid-beta deposition (Dong & Csernansky, 2009) that can result to hippocampal atrophy (Sawyer et al., 2012, p. 754). Vassilopoulou et al. (2013) conducted volumetric brain studies to compare three groups: (1) patients with melancholic major depressive disorder (MDD); (2) patients with psychotic MDD; and (3) normal patients. MRI results showed that patient groups had larger amygdala volumes and smaller left ASCVs for the patient groups compared to healthy groups (Vassilopoulou et al., 2013). These studies indicate that having chronic depression may result to hippocampal atrophy and larger amygdala volumes. Exercise can have a positive effect on depression through hippocampal neurogenesis (Wolf et al., 2010). Some researchers believe that if pharmacological treatments can promote neurogenesis, so can exercise (Eyre & Baune, 2012, p. 256; Wolf et al., 2010). Eyre and Baune (2012) reviewed the neuroimmunological effects of exercise on depression. Clinical evidence indicates that exercise overturns neuroimmune processes that are pertinent to stress-connected depressed behaviors (Eyre & Baune, 2012, p. 258). Some studies indicated that exercise lowered stress-based depression through lowered levels in IL-6, IL-18, CRP and TNF-alpha (Eyre & Baune, 2012, p. 258). Improving neuroimmune processes can result to hippocampal neurogenesis (Eyre & Baune, 2012, p. 256). Majority of the studies on hippocampal neurogenesis are animal studies. Li et al. (2013) showed that treadmill running increased neurogenesis for experimental mice groups. Exercise can also increase neurogenesis through increasing growth factors, such as the vascular endothelial growth factors (VEGF) (Fournier & Duman, 2012). VEGF serves as a neurotrophic factor that controls neurite outgrowth and maturation during development, and may affect a number of complex processes, for instance, learning and memory, in the adult brain (Fournier & Duman, 2012, p. 444). These theories underscore that exercise can have both physical and psychological effects that can effectively cure depression. Literature Review Some of the earliest researches on the effects of physical activity on depression were done during the 1970s and 1980s. From the earliest research until today, the focus has been on how physical activity can assuage symptoms of mental health disorders. Most of the information that has been gathered shows a positive outcome from exercise. Physical activity has shown to improve a person’s overall wellbeing, mood, and self-esteem. Researchers have also discovered that physical activity, such as sports involvement, can help a person because they put some value in it. Being involved in physical activity also helps a person to become more social by being able to share the sport with another person. It enables them to have something to talk about with others, by having more positive stories in their lives and reducing the negative storylines that usually come with a person experiencing some type of mental illness. The most recent research has provided information that states that in order for physical activity to make some type of impact on a person with mental illness a type of exercise needs to be prescribed along with, frequency, duration and intensity (Carless, 2008). Carek, Laibstain, and Carek (2011) stated that: Physical activity has been consistently shown to be associated with improved physical health, life satisfaction, cognitive functioning, and psychological well-being. Conversely, physical inactivity appears to be associated with the development of psychological disorders. Specific studies support the use of exercise as a treatment for depression. Exercise compares favorably to antidepressant medications as a first-line treatment for mild to moderate depression and has also been shown to improve depressive symptoms when used as an adjunct to medications. They showed that physical activity helps improve psychological and cognitive functioning, while lack of activity can contribute to psychological disorders. Dinas et al. (2011) reviewed the evidence published to date in order to determine whether exercise and physical activity can be used as therapeutic means for acute and chronic depression. Topics covered include the definition, classification criteria and treatment of depression, the link between β-endorphin and exercise, the efficacy of exercise and physical activity as treatments for depression, properties of exercise stimuli used in intervention programs, as well as the efficacy of exercise and physical activity for treating depression in diseased individuals. The presented evidence suggested that exercise and physical activity have beneficial effects on depression symptoms that are comparable to those of antidepressant treatments. Martin and Wade (2000) conducted an empirical investigation of the relationship between physical exercise and generalized distress for a Canadian sampling. They used a stress process framework that studied how chronic strains, self-esteem, mastery, and social support affect the connection between physical exercise and distress. Their data came from the 1994 wave of the National Population Health Survey that was conducted on 12,636 Canadians whose ages spanned 20 to 64 years old. They learned that physical exercise significantly predicts generalized distress when chronic strain, self-esteem and social support were controlled as influencing variables. Having more physical exercise decreased generalized distress, with no differences for moderate and highly active individuals (Martin & Wade, 2000, p. 304). Furthermore, this study showed that mastery affected the relationship between physical exercise and distress (Martin & Wade, 2000, p. 305). A sense of self-control is an important mediator when understanding how physical exercise affects distress. This study has an important implication to people with depression because it signifies that mastery and physical exercise can help them manage their feelings of distress. Exercise helps prevent and improve a number of health problems, including high blood pressure, diabetes and arthritis. Research on anxiety, depression and exercise shows that the psychological and physical benefits of exercise can also help reduce anxiety and improve mood. The links between anxiety, depression and exercise are not entirely clear — but working out and other forms of physical activity can definitely ease symptoms of anxiety or depression and make people with depression feel better. Exercise may also help keep anxiety and depression from coming back. Regular exercise probably helps ease depression in a number of ways, which may include: releasing feel-good brain chemicals that may ease depression (neurotransmitters, endorphins and endocannabinoids); reducing immune system chemicals that can worsen depression; and increasing body temperature, which may have calming effects. Regular exercise has many psychological and emotional benefits, too. It can help patients gain confidence because meeting exercise goals or challenges, even small ones, can boost self-confidence. Getting in shape can also make patients feel better about their appearance. Exercise can also take people’s minds from their worries. Exercise is a distraction that can get them away from the cycle of negative thoughts that feed anxiety and depression. In addition, exercise can boost social interaction. Exercise and physical activity may give people the chance to meet or socialize with others. Exercise is also a form of coping with stress in a healthy way. Discussion Conclusions Recommendations References American Psychiatric Association (APA). (1994). Diagnostic and Statistical Manual of Mental Disorders (4th ed.) (DSM-IV). Washington, DC: APA. Barth, J., Munder, T., Gerger, H., Nuesch, E., Trelle, S., Znoj, H., Juni, P., & Cuijpers, P. (2013). Comparative efficacy of seven psychotherapeutic interventions for patients with depression: A network meta-analysis. 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