Excessive Exercise as an Eating Disorder Symptom

Exercise is generally seen as a virtue; therefore, you may wonder how it could possibly be bad for you. For most people, exercise does confer significant health and mental health benefits. However, for those with eating disorders, excessive exercise is a common symptom and can play a role in the development and maintenance of the disorder. Our culture’s celebration of exercise makes it so that excessive exercise is often not recognized or taken as seriously as it should.

This article will describe excessive exercise as it has been studied by eating disorder researchers, and then review how excessive exercise manifests itself in various eating disorders, the risks of overexercising, and what to do if you think you (or a loved one) are engaging in too much exercise.

Overview

Whereas most people would understand self-induced vomiting to be a negative eating disorder behavior, they would generally not think the same of exercise. Those who exercise excessively are often praised for their motivation and self-discipline. But taken to an extreme, this behavior can have serious consequences.

Link to Eating Disorders

Excessive or driven exercise is a common component of different types of eating disorders. It may be found among patients with anorexia nervosa, bulimia nervosa, and muscle dysmorphia, as well as other specified feeding and eating disorder (OSFED) and subclinical presentations. In the case of restrictive eating disorders, including anorexia, there is even some evidence that increased exercise may be a fundamental biological reaction. 

Activity-Based Anorexia in Rats. Animal studies have demonstrated that eating disorders can give rise to excessive exercise behavior, by inducing what is called “Activity-Based Anorexia” in rats. When researchers restrict rats’ food intake while giving them unlimited access to a wheel, many of the rats become hyperactive and run more than they did prior to the food-restriction. Paradoxically, these rats opt to continue running rather than eat during the short intervals of time food is made available to them. If allowed, they will literally run themselves to death.

These rats display the puzzling behavior of self-starvation exhibited in anorexia nervosa. One would expect that rats (and humans) who are starving would become less, rather than more, active. Yet in young children who develop anorexia nervosa, restricted intake is usually accompanied by increased activity. Youngsters with anorexia often present as hyperactive—they won’t sit still, they fidget, and they often run around aimlessly. They do not express a conscious attempt to burn calories the way older adolescents and adults do. Thus, excessive activity or exercise is postulated to be a more basic drive that gets turned on by the energy imbalance of restricted intake.

Exercise in Anorexia Nervosa. Hyperactivity is a common, intriguing, and well-documented symptom of anorexia nervosa, noted as early as 1873 by the French physician Ernest-Charles Lasègue, one of the earliest writers about the disorder. Lasègue observed that patients with anorexia exhibited high levels of activity seemingly incompatible with their impoverished nutrition:

Another ascertained fact is, that so far from muscular power being diminished, this abstinence tends to increase the aptitude for movement. The patient feels more light and active, rides on horseback [the French text also mentions: ‘long walking-tours'], receives and pays visits, and is able to pursue a fatiguing life in the world without perceiving the lassitudes he would at other times have complained of. (Lasègue, 1873, p.266)

In one study, 37 percent to 54 percent of patients with anorexia nervosa (depending on subtype) engaged in excessive exercise. Patients may underreport the amount of time that they engage in physical activity, making it hard for caregivers and treatment professionals to fully assess. 

One patient in a study about exercise reported:

"Before I attended treatment, I only sat down during meal times, or else I felt I did not deserve to sit still. I was incredibly restless, so it was difficult to relax…I feel like I am being compelled to exercise…"

Excessive exercise in anorexia nervosa is associated with younger age and higher rates of anxious/obsessional and perfectionistic traits.

Exercise in Bulimia Nervosa. Excessive exercise has been included in the diagnostic criteria for bulimia nervosa since the publication of DSM-III-R in 1987. The current diagnostic criteria (DSM-5) for bulimia nervosa specify that there is compensatory behavior for binge eating which can include self-induced vomiting, but also intermittent fasting, laxative use, diuretics, and excessive exercise.

Excessive exercise is a common compensatory behavior in individuals with bulimia nervosa. In one study, 20 percent to 24 percent of patients with bulimia nervosa engaged in excessive exercise. Among patients with bulimia nervosa, excessive exercise is associated with greater baseline eating disorder severity as well as poorer treatment outcome.

Exercise in Muscle Dysmorphia. Excessive exercise is a common symptom of muscle dysmorphia, a condition that sometimes affects bodybuilders. Some researchers believe it to be a variation of anorexia nervosa characteristics of patients with a more traditional masculine gender identity. It is sometimes known as "reverse anorexia." Currently, this disorder is classified diagnostically as a type of body dysmorphic disorder versus an eating disorder.

Muscle dysmorphia is characterized by the persistent belief that one is not muscular enough and associated behaviors related to increasing musculature including an extreme exercise program and dietary intake designed to build bulk (often with a focus on protein). Supplements and steroids are sometimes used in the pursuit of muscle. Among men with muscle dysmorphia, approximately 71 percent lift weights excessively and 64 percent exercise excessively. 

Excessive Exercise in OSFED and Subclinical Disordered Eating. There is little research on excessive exercise in OSFED. In subclinical samples, the relationship between compulsive exercise and elevated scores on measures of eating psychopathology is well established. Behaviors such as dieting and exercise often coexist and reinforce one another. It is also the case that excessive exercise in the absence of disordered eating or disordered eating attitudes is believed to be less clinically significant and less impairing.

Risks

Exercise in patients with eating disorders and disordered eating can be dangerous. Patients may exercise and not fuel properly, putting themselves at risk for a variety of serious medical complications. These complications can include electrolyte imbalances, heart problems, muscle wasting, injuries, and sudden death. Patients with anorexia often have weak bones and so may generally be more likely to experience fractures; the physical strain associated with over-exercising exacerbates this risk.

Recovery

Excessive exercise immediately following hospital discharge is a significant predictor of relapse. Exercise can both maintain the beliefs that keep one caught in an eating disorder and be physically counterproductive when weight gain is a goal of treatment.

For this and other reasons, it is common for treatment professionals to recommend cessation of exercise in individuals with eating disorders until they are stable in recovery. The idea of allowing an individual in recovery continued participation in a sport as motivation to recover is enticing, but often backfires for the reasons cited above.

Signs and Symptoms

Excessive exercise may be difficult to distinguish, especially among athletes. The key feature that determines whether the exercise is problematic lies less in the quantity of activity than it does in the motivations and attitudes behind it: feeling exercise as a compulsion; exercising primarily to influence shape and weight; and feelings of guilt after missing an exercise session. An elite athlete may engage in more total time exercising than a person with an eating disorder, but we could define the eating disorder person’s exercise as excessive while the elite athlete might not have the attitudes about exercise that would qualify it as excessive or problematic.

It should also be noted that the prevalence of eating disorders is higher among athletes, especially those in sports that emphasize leanness than it is in the general population. Thus, athletes who are exhibiting signs of an eating disorder should be assessed.

Recovery advocate Jenni Schaefer has made the Compulsive Exercise Test, a measure used to assess excessive exercise, available on her website.

Treatment

If you or someone you know is exhibiting signs of excessive exercise and/or an eating disorder, eating disorder treatment, including psychotherapy, can help address both the eating disorder and exercise obsession. Cognitive-behavioral therapy, which helps to modify behaviors as well as underlying beliefs about exercise, can help individuals to develop moderation and balance. If you are a parent of a child in treatment, it may be beneficial for you to help limit or restrict their exercise.