
A mental illness is defined, according to the National Alliance on Mental Illness, as "a condition that impacts a person's thinking, feeling or mood and may affect his or her ability to relate to others and function on a daily basis" ("Mental ... "). People worldwide suffer from mental illnesses that can cause difficulties in everyday life as well as in personal relationships. Medications and other preventative measures are used to keep mental illnesses at bay; however, exercise has primarily been overlooked as an alternative and offers the potential to be a viable option for treatment. There is an overall positive effect of exercise on many mental illnesses including anxiety, depression, schizophrenia, substance abuse and addiction, eating disorders, and cognitive decline such as Alzheimer's. There are studies that show no effect or even a negative effect on some of these disorders; however, the majority of the official and non-official studies report and overwhelmingly positive effect on most mental illnesses. 

Anxiety can come in many forms with many different symptoms and triggers but the general classification of an anxiety disorder is, "persistent, excessive fear or worry in situations that are not threatening" ("Anxiety ... "). Results of different studies on the effects of exercise showed improvement in specific forms of anxiety including panic attacks, social phobia, specific phobia, and agoraphobia (Goodwin). The general consensus is that exercise has a very positive effect on anxiety in the majority of people with the disorder. People with higher levels of anxiety who regularly preform aerobic exercise and were not physically fit to begin with tend to show the best results (Landers). At the end of a ten week study on people with anxiety, those with anxiety who exercised for the ten weeks had much better results than the placebos who did not exercise at all (Stathopoulou, Powers, Berry, Smits, Otto). More studies were conducted with different age groups, types of exercise, and durations of exercise and the constant variable that had the most effect on anxiety was not the age or the type of exercise, but the duration. Those who preformed exercise for more than twenty minutes showed the most improvement across the board, while those who did not continued to have symptoms (Callaghan). The only argument against the aid of exercise to people who suffer with anxiety is that some studies show little to no effect on anxiety. This argument; however; is invalid because the case studies are unofficial and often do not take into consideration the age of the person, the severity of the disorder, the duration of exercise, or the amount of time that the person has been exercising in total (Barr, Sallis, Needle). 

Depression is another mental disorder researched in conjunction with exercise. Depression is "a state of being associated with feelings of hopelessness or a sense of defeat. People with depression often feel "down" or "blue" even when circumstances would dictate otherwise" (Landers). Exercise is a very helpful tool when treating depression because it produces endorphins that improve a person's overall mood. The effect of exercise on depression is similar to that of anxiety, the best results come from vigorous exercise regularly preformed by patients with more severe cases of depression (Landers). Evidence suggests that, "depression is indeed associated with low activity/fitness and that those who maintain activity are less likely to develop depression" (Biddle, Fox, Boutcher). There is an article that states that exercise does not have much of an effect on depression; however, this article was written in 1974, which shows how the research is out of date while the official studies of the modern day prove the benefits of exercise for this mental illness (Barr, Sallis, Needle). Along with the research of how exercise can help patients suffering with depression and anxiety, studies have also been done with schizophrenics.

Schizophrenia is "a serious mental illness that interferes with a person's ability to think clearly, manage emotions, make decisions and relate to others. It is a complex, long-term medical illness, affecting about 1% of Americans" ("Schizophrenia"). There was a ten week study conducted that consisted of biweekly exercise sessions, the results showed significantly reduced auditory hallucinations and improve self esteem, sleep patterns, and overall behavior. Another study consisted of cycling four days a week for sessions of thirty minutes. These results showed "reduced depression, increased general well-being and improved aerobic fitness" in patients who suffer from schizophrenia (Daley). The majority of opinions about the effects of exercise on this disorder are in support of the use of exercise as an improvement but not a complete treatment of schizophrenia. 

There are mixed opinions although other disorders have shown almost definite positive results with the use of exercise, there is controversy about the effects of exercise on substance abuse and addiction. Substance abuse and addiction in general can include addiction to drugs, alcohol, food, sex, and most of anything else. Many of the studies on the effects of exercise on these illnesses are positive according to both official and unofficial studies. The results of a study show that fifty-eight alcoholics who preformed regular exercise showed higher abstinence rates three months after treatment than those who did not preform exercise (Barr, Sallis, Needle). Exercise is said to help those who struggle with addiction because it releases dopamine in the brain which is the same chemical released when drinking, taking drugs, or having sex (Breene). Studies indicate that exercise is especially beneficial to people with substance abuse issues who have recently been released from treatment. This is because the exercise gives them something to focus on and helps them cope with the lifestyle changes that sobriety entails. Active alcoholics and drug addicts who exercise exhibit less alcohol misuse than those who do not exercise. (Daley) A strong factor in the reduction of cravings in people with this disorder further supports that exercise is beneficial to people who struggle with anxiety and depression. This is because people with substance abuse issues often struggle with anxiety or depression which can lead to them using substances to cope with their disorder. A study was conducted in which active alcoholics took up running for eight weeks and the results showed a decrease in the consumption of alcohol in its participants (Stathopoulou, Powers, Berry, Smits, Otto).

While there are many benefits to exercise when dealing with substance abuse and addiction, there are many arguments against the use of exercise as a treatment. The issue with exercise when treating addiction is the possibility of the person becoming addicted to exercise which would only make it a replacement for the old addiction. This constant need to exercise otherwise knows as "running addiction" (Barr, Sallis, Needle) can cause the complete neglect of responsibilities and personal relationships. Substance abuse and addiction are similar to eating disorders such as anorexia and bulimia which can relate to this "running addiction" (Barr, Sallis, Needle).

Eating disorders are any abnormal type of eating patterns and can be classified as Anorexia Nervosa, Binge Eating Disorder, Bulimia Nervosa, Purging, and Night eating syndrome ("Types ... "). Similar to substance abuse and addiction, the opinions and views are mixed when it comes to whether or not exercise is positive or negative to eating disorders. Some concerns with using exercise as a treatment for eating disorders is that it could cause more weight loss; however, there was a study conducted to prove otherwise. The study used 254 women with anorexia nervosa, half acted as the placebo and the other half were assigned an exercise regiment. The women who exercised had a more positive outcome because they gained one third more weight than the women who did not exercise. (Stathopoulou, Powers, Berry, Smits, Otto) Another concern about the use of exercise as an aid to the treatment of eating disorders is the issue of addiction. "Running addiction" (Barr, Sallis, Needle) can occur in people who suffer from eating disorders, not just those with substance abuse and addiction problems. It is unclear whether or not this addiction to running is a result or the cause of anorexia nervosa; however, it can be common especially in people with this disorder (Barr, Sallis, Needle). 

Cognitive decline can lead to dementia and Alzheimer's but is often improved by exercise. Cognitive decline, also known as mild cognitive impairment, "causes a slight but noticeable and measurable decline in cognitive abilities, including memory and thinking skills. A person with MCI is at an increased risk of developing Alzheimer's or another dementia" ("Mild ... "). Exercise helps prevent cognitive decline because it prevents the hippocampus, the part of the brain that controls memory and learning, from degenerating (Breene). Exercise, in this case, is not a treatment for cognitive decline; however, it does improve mental and physical health overall. After looking at studies focusing on cognitive functioning in the elderly, the results showed that aerobic exercise for twenty to thirty minutes, three to five times a week showed slight improvement in cognitive functioning (Callaghan). 

While the results of the majority of studies are positive ones, there is still some skepticism on how effective the exercise method actually is when treating mental illness. Some concerns that still remain include: Addiction to exercise; compulsiveness; decreased involvement in job, marriage, and so on; escape or avoidance of problems; exacerbation of anorexia nervosa; exercise deprivation effects; fatigue; over competitiveness; overexertion; poor eating habits; preoccupation with fitness, diet, and body image; and self centeredness (Barr, Sallis, Needle). These are all valid concerns; however, the benefits outweigh the costs for the majority of people with these mental illnesses. Exercise provides a decrease in anxiety and depression, a reduction in auditory hallucinations and better sleep for people with schizophrenia, improvement for people with substance abuse issues and addiction, weight gain in people with eating disorders, and the slowing of cognitive decline because of the preservation of the hippocampus therefore preventing types of dementia including Alzheimer's. Exercise should not be written off as a method that does not work because there are studies and personal accounts that prove otherwise.

Factors that could have an impact on the effectiveness of exercise include the type of exercise, the duration of that exercise, and how often the exercise is preformed. There are many different opinions on this subject because different studies yield different results depending on the duration of the exercise and how often it is preformed. One study was conducted using fifteen males and fifty females all in the age range of eighteen to thirty years old. Some were assigned to a control group that stretched for thirty minutes three times per week while others were assigned to an exercise group that participated in a cycling class three times a week for thirty minute sessions.  The results of this study for depression showed that the cycling-exercise group exhibited a significantly larger decrease in depression than those in the stretching-control group. The results for anxiety showed a slight, but not notable, decrease in symptoms for those in the cycling-exercise group opposed to the stretching-control group. The results for both depression and anxiety showed a decrease in symptoms which means that, according to this study, aerobic exercise has a more of a positive impact on people who suffer from these mental illnesses than stretching does. (Wipfli, Landers, Nagoshi, Ringenbach)

Two other studies measured the effects of aerobic exercise versus anaerobic exercise which resulted in very different outcomes from the previous study. In the first study, 40 women with depression were randomly assigned to either a running group, a weight lifting group, or a control group. They exercised four times a week for eight weeks and the results showed that both groups showed the same amount of decrease in depression symptoms. In the second study, 90 participants were assigned to either an aerobic group or a muscle strength training group. Each one of the twenty-four sessions lasted for one hour and the study took place over the course of eight weeks. Just as in the first study, the final results of both groups showed no difference in the effectiveness of the aerobic group versus the muscle strength training group. (Stathopoulou, Powers, Berry, Smits, Otto). In conclusion, when looking at the three different studies, the overall result is that there is a very small difference between the effectiveness of aerobic and anaerobic exercises, both prove to be beneficial when treating mental illnesses.

Another factor that contributes to the treatment of mental illnesses using exercise has to do with overall psychological well being brought on by the social stigma that surrounds being physically fit versus overweight. Physical health is viewed as beneficial to everyday life and as more "socially acceptable" in todays society, overweight people can often feel rejection socially because of this standard. Being overweight tends to make a person more self conscious and causes them to have self esteem issues which can lead to disorders including social anxiety, depression, and especially eating disorders. Eating disorders can stem from a need to look perfect so that others accept them, this supports the idea that being physically fit is more desirable socially than being overweight is. People relate being physically fit to being more capable, younger, well educated, and having a higher income. Mental disorders can arise from feeling rejected and undesirable socially, which shows how exercise can be used as a preventative measure against mental disorders. (Hayes, Ross)

The outcome of using exercise as a way to treat mental illnesses is overwhelmingly positive; however, it is unclear whether it is enough on its own or if it should be paired with medication. One study consisted of 156 depressed adults who were each put into either a medication group, an exercise group, or a combination of exercise and medication group. The results of this study showed a more positive effect on people with depression who used exercise alone rather than a combination of the medication and exercise (Stathopoulou, Powers, Berry, Smits, Otto). Other research suggests that exercise should be incorporated in treatment but it should not replace medication or other methods of treatment (Callaghan). The results are mixed but disregarding the role of medication in the treatment of mental illnesses, exercise produces consistent positive results when treating certain disorders. 

After reviewing the studies and research, it can be concluded that exercise has an overall positive effect of people who suffer from anxiety, depression, schizophrenia, substance abuse and addiction, eating disorders, and cognitive decline. Age and the type of exercise do not have a significant impact on the effectiveness of this treatment method; however, the duration of the exercise and the amount of times the exercise is preformed in a week have an impact on the effectiveness of this treatment. The relation between medication and exercise when treating these mental illnesses is undetermined specifically because of the lack of research on the effects of the combination between exercise and medication as a treatment in itself. What can be concluded by the mixed results of these studies is that exercise can be used as a treatment method on its own for less severe cases of these disorders. Participants in the studies post-treatment reported extremely positive feedback and claimed that exercise acted as "antidepressant" (Daley) and caused them, "mood-elevation, moderate anxiety-reduction, increased self esteem, and improved concentration" (Daley). Exercise, whether aerobic or anaerobic, is a relatively undiscovered treatment method but it is an extremely viable one according to the numerous studies that prove its positive effects. Its role as a treatment method should be further explored and utilized because of its positive effects on mental illnesses and overall psychological well being. 

