Exercise addiction

An exercise addiction can have harmful consequences although it is not listed as a disorder in the latest revision of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV). This type of addiction can be classified under a behavioral addiction in which a person’s behavior becomes obsessive, compulsive, and/or causes dysfunction in a person's life. The next revision of the DSM (DSM-5) will include an addictions and related disorders section; gambling is the only non-substance addiction that is likely to be included. Other non-substance addictions, such as exercise addiction, are being researched but their inclusion is undetermined.

Exercising has the potential to become maladaptive: it may become an addictive behavior and can cause a person to not have adequate rest. Exercise addiction shows a high comorbidity with eating disorders. Exercise is considered to be both physically and psychologically beneficial to health, but exercise without limits and to damaging degrees can be harmful or become addictive. Differentiating between addictive and healthy exercise behaviors is difficult but there are key factors in determining which category a person may fall into.

Classification
A concrete classification of exercise addiction has proven to be difficult due to the lack of a specific and widely accepted definition. While excessive exercise is the overarching theme with exercise addiction, the term also includes a variety of symptoms like withdrawal, "exercise buzz", and impaired physical function. Excessive exercise has been classified in different ways; sometimes as an addiction and sometimes as a compulsion. With an addiction, individuals become "hooked" to the feeling of euphoria and pleasure that exercise provides. This pleasure keeps the individual from stopping and leads to excessive exercise. With a compulsion people often do not enjoy repeating certain tasks but feel like it will fulfill a duty that is required of them. There are many opinions on whether concrete diagnostic criteria should be created for this type of addiction. Some say preoccupation with exercise that causes significant impairment in a person's life, not due to another disorder, may be enough criteria to label this disorder. Others say there is not enough information about exercise addiction to develop diagnostic criteria. The term "excessive exercise" continues to be used and the acceptance of the term "exercise addiction" continues to be debated.

Signs and symptoms
Five indicators of exercise addiction are:
 * 1) An increase in exercise that may be labeled as detrimental, or becomes harmful.
 * 2) A dependence on exercise in daily life to achieve a sense of euphoria; exercise may be increased as tolerance of the euphoric state increases.
 * 3) Not participating in physical activity will cause dysfunction in one's daily life.
 * 4) Withdrawal symptoms following exercise deprivation including anxiety, restlessness, depression, guilt, tension, discomfort, loss of appetite, sleeplessness, and headaches.
 * 5) High dependence on exercise causing individuals to exercise through trauma and medical conditions.

Key differences between healthy and addictive levels of exercise include the presence of withdrawal symptoms when exercise is stopped as well as the addictive properties exercise may have leading to a dependence on exercise.

Causes
Exercise addiction is thought to be related to the euphoric feelings resulting from the rapid release of endorphins that occurs during intense bouts of exercise. Although the evidence is not conclusive, there is a high correlation between exercise addiction and endorphins. Endorphins work by activating opiate receptors in the brain causing pain relief and are also correlated with causing euphoric feelings. The decrease of pain and increase in euphoric feelings creates a positive feedback loop associated with exercise which is thought to be a cause of addiction. This feedback loop also helps to explain why intensity of exercise increases over time with exercise addiction. For individuals who exercise more frequently the effects of endorphins are decreased. A person with an exercise addiction will need to increase the frequency, intensity, and/or time of exercising to reach the desired euphoric feelings.

Assessment
Different assessment tools can be used to determine if an individual is addicted to exercise. Most tools used to determine risk for exercise addiction are modified tools that have been used for assessing other behavioral addictions. Tools for determining eating disorders can also show a high risk for exercise addiction.

The Obligatory Exercise Questionnaire was created by Thompson and Pasman in 1991, consisting of 20 questions on exercise habits and attitudes toward exercise and body image. Patients respond to statements on a scale of 1 (never) to 4 (always). This questionnaire aided in the development of another assessment tool, the Exercise Addiction Inventory.

The Exercise Addiction Inventory was developed by Terry et al in 2004. This inventory was developed as a self-report to examine an individual's beliefs toward exercise. The inventory is made up of six statements in relation to the perception of exercise, concerning: the importance of exercise to the individual, relationship conflicts due to exercise, how mood changes with exercise, the amount of time spent exercising, the outcome of missing a workout, and the effects of decreasing physical activity. Individuals are asked to rate each statement from 1 (strongly disagree) to 5 (strongly agree). If an individual scores above 24 they are said to be at-risk for exercise addiction.

Treatment
Behavioral addiction and substance abuse disorders are treated similarly; treatment options include exposure and response prevention. No medications have been approved for the treatment of behavioral addictions. Studies have shown promise in the use of glutamatergic altering drugs to treat addictions other than exercise. Exercise addictions comorbid in patients with an eating disorder may be treated through psychotherapy involving education, behavioral interventions, and a strengthened family support structure. In treating the eating disorder, obsessions and compulsions produced by obscured body image ideals will also be treated, this includes exercise addiction.

Epidemiology
Most research has focused on adult population or on college students, but little is known about epidemiology of behavioral addictions in adolescence. A study conducted by Villella et al looked at a group of students and the prevalence of various addictions. His results showed exercise addiction was the second most prevalent, after compulsive buying. High risk groups that appear to have exercise addiction include athletes in sports encouraging thinness or appearance standards, young and middle-age women, and young men.

Prognosis
Individuals with exercise addiction may put exercise above family and friends, work, injuries, and other social activities. If not identified and treated, an exercise addiction may lead to a significant decline in one's health.

Comorbidity
An addiction, by definition, includes repeated compulsive behaviors that negatively affect daily living. There are two ways to classify addictive behaviors: substance addiction and process addiction. An exercise addiction is a type of process addiction, in which an individual's mood toward a certain event becomes dependent on addictive behaviors. Many educational, occupational, and social activities are stopped due to excessive exercising. Depression may develop if exercise is neglected or may result from reoccurring physical injuries that limit exercise. Exercise addiction is often related to obsessive-compulsive disorder as exercise addicts may have obsessions or compulsions toward physical activity. Exercise addiction is also commonly associated with eating disorders as a secondary symptom of bulimia or anorexia nervosa. When diagnosing bulimia, exercise addiction is referred to as a compensatory behavior and indicator of the underlying disorder. Research also shows exercise addiction influences not only the development of eating disorders but also their maintenance.