Exercise interventions for women with anorexia nervosa: a review of the literature

Gains in relative cortical area during growth and their relationship to nutrition, body size, and physical activity

OBJECTIVES

In studies of growth in the past, low percentage of cortical area (%CA) is commonly attributed to poor general health, due to factors including poor nutrition, low socioeconomic status, or other physiological stressors. What constitutes low relative cortical dimensions has not been established across a diverse range of human skeletal samples. This study examines %CA in a large immature skeletal sample to establish typical variation in humans with consideration of both body mass and subsistence strategy.

MATERIALS AND METHODS

Percentage of cortical area was calculated at the midshaft of the humerus, femur, and tibia in seven skeletal samples. Age at death was estimated from dental development, and body mass from bone dimensions. Patterns of %CA with age and log-transformed body mass were examined in the pooled sample and compared among samples using LOESS regression, Welch's ANOVA, and Kruskal-Wallis tests.

RESULTS

Across all samples, %CA displays a generally non-linear pattern, but variation in %CA with age was high, particularly in samples with lower levels of %CA. There was no relationship between %CA and age-adjusted body mass.

DISCUSSION

The lack of a relationship between %CA and body mass suggests that %CA should not be used as an indicator of mechanical loading. The variation present across samples implies that appositional bone growth is affected by physiological stress in varying ways. Without a deeper understanding of what is "typical" for long bone development, it is impossible to draw conclusions about individual or population level health.

A machine learning investigation into the temporal dynamics of physical activity-mediated emotional regulation in adolescents with anorexia nervosa and healthy controls

OBJECTIVE

Anorexia nervosa (AN) is commonly experienced alongside difficulties of emotion regulation (ER). Previous works identified physical activity (PA) as a mechanism for AN sufferers to achieve desired affective states, with evidence towards mitigation of negative affect. However, temporal associations of PA with specific emotional state outcomes are unknown.

METHOD

Using lag-ensemble machine learning and feature importance analyses, 888 affect-based ecological momentary assessments across N = 75 adolescents with AN (N = 44) and healthy controls (N = 31) were analysed to explore significance of past PA, measured through passively collected wrist-worn actigraphy, with subsequent self-report momentary affect change across 9 affect constructs.

RESULTS

Among AN adolescents, later lags (≥2.5 h) were important in predicting change across negative emotions (hostility, sadness, fear, guilt). AN-specific model performance on held-out test data revealed the holistic "negative affect" construct as significantly predictable. Only joviality and self-assurance, both positively-valenced constructs, were significantly predictable among healthy-control-specific models.

DISCUSSION

Results recapitulated previous findings regarding the importance of PA in negative ER for AN individuals. Moreover, PA was found to play a uniquely prominent role in predicting negative affect 4.5-6 h later among AN adolescents. Future research into the PA-ER dynamic will benefit from targeting specific negative emotions across greater temporal scales.

Cardiopulmonary exercise testing for patients with anorexia nervosa: a case-control study

PURPOSE

Patients with anorexia nervosa (AN) require appropriate nutrient therapy and physical activity management. Eating disorder treatment guidelines do not include safe, evidence-based intensity criteria for exercise. This study used cardiopulmonary exercise testing (CPX) to evaluate the exercise tolerance of patients with AN.

METHODS

CPX was performed with 14 female patients with AN admitted to a specialized eating disorder unit between 2015 and 2019. Their anaerobic threshold (AT) was determined by assessing their exercise tolerance using CPX and compared with 14 healthy controls (HC). The metabolic equivalents (AT-METS) were compared when AT was reached. We examined factors related to AT (AN-AT) in the AN group, including age, body mass index (BMI), previous lowest weight, minimum BMI, past duration of BMI < 15, exercise history, and ΔHR (heart rate at the AT-resting heart rate).

RESULTS

The AT of the AN group (BMI: 15.7 [Mean] ± 1.8 standard deviation [SD]) was significantly lower than that of the HC group (BMI: 19.7 ± 1.8) (AN: 10.0 ± 1.8 vs. HC: 15.2 ± 3.0 ml/kg/min, P < 0.001). AT-METS was also significantly lower in the AN group than in the HC group (AN: 2.9 ± 0.52 vs. HC: 4.4 ± 0.91, P < 0.001). AN-AT was highly influenced by ΔHR.

CONCLUSIONS

This study showed that AT and AT-METS were lower in patients with AN than in HC. Patients with AN should be prescribed light-intensity aerobic exercise, and the current findings may help develop future physical management guidelines for patients with AN.

LEVEL OF EVIDENCE

III: Evidence obtained from case-control analytic studies.

Measuring exercise in eating disorder patients: a Delphi study to aggregate clinical and research knowledge

BACKGROUND

Exercise is a prominent feature of most eating disorders, and has been shown to have a number of detrimental effects on treatment outcome. There is some disagreement in the literature regarding the construct of compulsive exercise, and assessment and treatment varies significantly. This study therefore aimed to aggregate expert clinicians' and researchers' views on how to define and measure compulsive exercise in eating disorder patients. The expert panel was also asked about questionnaire design, and possible problems when measuring compulsive exercise.

METHOD

This study used the Delphi method to establish consensus amongst an expert panel. Three successive rounds of questionnaires were distributed to the panel over a period of six months. The first round consisted of four open-ended questions regarding the definition and measurement of compulsive exercise in eating disorder patients. For Round 2, 70 statements were derived from the answers, and panelists were asked to rate each item on a Likert-based scale. An 85% consensus level was chosen. In Round 3, 44 statements were re-rated by the panel.

RESULTS

Seventeen of 24 participants completed all three rounds of the study. Consensus was achieved for 63% of the items, while 18.5% reached near consensus, and 18.5% did not reach consensus after Round 3. The panel agreed on a number of important aspects of compulsive exercise. Several suggestions regarding the format of a questionnaire assessing this behavior were also endorsed. The panel further identified common difficulties when assessing compulsive exercise in eating disorder patients, notably a lack of consensus still apparent in the literature.

CONCLUSION

The current findings constitute a further step towards a unified definition of compulsive exercise, and contribute important suggestions to the measurement of this behavior.

Exercise therapy in the treatment of anorexia nervosa: Its effects depending on the type of physical exercise-A systematic review

BACKGROUND AND PURPOSE

Clinical research focusing on the effectiveness of exercise therapy (ET) in patients with anorexia nervosa (AN) shows increasing interest in the last decade. The aim of this systematic review was to provide an overview of quantitative studies that have examined the impact of ET in AN patients and to examine its specific effects on physical and mental health according to the type of physical exercise (PE) practiced.

METHODS

The review was carried out based on the PRISMA 2020. Electronic databases PubMed, Web of Science, Embase, and Wiley were searched from inception to December 2021. Quantitative studies assessing the effects of ET interventions on AN patients were included and study quality was assessed using the PEDro scale.

RESULTS

A total of 27 studies were selected, including 13 randomized controlled trials. Regarding outcomes measured, results showed that aerobic and resistance exercise improved muscle strength, that mind-body PE decreased main symptoms of AN and mental health, and that combined PE reduced dysfunctional exercise and improved weight gain.

CONCLUSION

The findings suggest that ET intervention can induce benefits and has no deleterious effects on patients. In addition, specific effects on anorexia symptoms and physical and mental health have been observed according to the type of PE. However, this review reported several methodological weaknesses, including a lack of control group or randomization and statistical misconduct. Finally, ET intervention parameters were heterogeneous, and ET intervention generally lacked details, making reproducibility and comparability difficult. All these limitations underscore the need for a more rigorous methodology for further research.

What role can accredited exercise physiologists play in the treatment of eating disorders? A descriptive study

Including exercise alongside other therapeutic approaches may help to address dysfunctional exercise use and improve eating disorder treatment outcomes. However, traditional treatment teams often lack the expertise needed to safely prescribe exercise. The aims of this study were to explore the perceptions and experiences of Accredited Exercise Physiologists (AEPs) relating to working with clients diagnosed with eating disorders to identify the role they play in the treatment of eating disorders and identify future training needs. Individual semi-structured telephone interviews were conducted with 12 (n = 9 females) AEPs working in the eating disorders field. Thematic analysis was conducted to extract major themes from the interview transcripts. Five major themes were identified: (1) The role of AEPs in the treatment of individuals with eating disorders is comprehensive; (2) Treatment is more effective when all components are addressed; (3) The absence of therapeutic exercise within standard treatment protocols reflects limitations of traditional scope of practice and knowledge about the role of AEPs; (4) Methods of acquiring further knowledge are insufficient for those in current practice; and (5) Accredited comprehensive training is currently unavailable but needed. This qualitative study showed that AEPs believe they can play a major role in the treatment of eating disorders and that treatment outcomes for individuals are likely to be greatly enhanced when dysfunctional exercise is addressed. Multidisciplinary training is needed.

Suppression of food restriction-evoked hyperactivity in activity-based anorexia animal model through glutamate transporters GLT-1 at excitatory synapses in the hippocampus

Severe voluntary food restriction is the defining symptom of anorexia nervosa (AN), but anxiety and excessive exercise are maladaptive symptoms that contribute significantly to the severity of AN and which individuals with AN have difficulty suppressing. We hypothesized that the excitability of hippocampal pyramidal neurons, known to contribute to anxiety, leads to the maladaptive behavior of excessive exercise. Conversely, since glutamate transporter GLT-1 dampens the excitability of hippocampal pyramidal neurons through the uptake of ambient glutamate and suppression of the GluN2B-subunit containing NMDA receptors (GluN2B-NMDARs), GLT-1 may contribute toward dampening excessive exercise. This hypothesis was tested using the mouse model of AN, called activity-based anorexia (ABA), whereby food restriction evokes the maladaptive behavior of excessive wheel running (food restriction-evoked running, FRER). We tested whether individual differences in ABA vulnerability of mice, quantified based on FRER, correlated with individual differences in the levels of GLT-1 at excitatory synapses of the hippocampus. Electron microscopic immunocytochemistry (EM-ICC) was used to quantify GLT-1 levels at the excitatory synapses of the hippocampus. The FRER seen in individual mice varied more than 10-fold, and Pearson correlation analyses revealed a strong negative correlation (p = .02) between FRER and GLT-1 levels at the axon terminals of excitatory synapses and at the surrounding astrocytic plasma membranes. Moreover, synaptic levels of GluN2B-NMDARs correlated strongly with GLT-1 levels at perisynaptic astrocytic plasma membranes. There is at present no accepted pharmacotherapy for AN, and little is known about the etiology of this deadly illness. Current findings suggest that drugs increasing GLT-1 expression may reduce AN severity through the reduction of GluN2B-NMDAR activity.

Physical activity behaviors and attitudes among women with an eating disorder: a qualitative study

BACKGROUND

Physical activity (PA) is an integral part of healthcare for the general population and individuals with psychiatric disorders. However, PA is significantly more complex for and related to both healthy (e.g., reduced anxiety and depressive symptoms) and unhealthy outcomes (e.g., intrusive, repetitive thoughts that lead to abnormally high levels of PA) among women with an eating disorder (ED). Consequently, many healthcare professionals recommend abstinence from PA during ED treatment. Despite this, women may remain engaged in PA during ED treatment or resume PA shortly thereafter. Little has been done to understand women's PA behaviors and attitudes and to explore how they integrate PA into their lives during and after ED treatment. Thus, this study sought to explore PA behaviors and attitudes among women with an ED.

METHODS

Nine women who self-reported receiving an ED diagnosis participated in semi-structured interviews, which were transcribed and analysed thematically.

RESULTS

Six interrelated themes were constructed to represent participants' PA experiences: PA as a lifestyle, PA can be beneficial, How I feel when I can't do PA, Being cautious about PA, Reactions to healthcare professionals' practice of recommending abstinence from PA during ED treatment, and PA programming thoughts.

CONCLUSIONS

Overcoming dysfunctional PA behaviors (e.g., engaging in abnormally high levels of PA) and attitudes (e.g., associating PA with caloric expenditure) can be a long and complicated journey for women with an ED. Nevertheless, women with an ED want PA to be integrated into their ED treatment protocol for two key reasons, namely to accrue the benefits associated with PA and to learn how to engage in PA in adaptive and healthy ways.

Treatment of compulsive exercise in eating disorders and muscle dysmorphia: protocol for a systematic review

BACKGROUND

Compulsive exercise is a core feature of both eating disorders and muscle dysmorphia. Earlier models of treatment recommended complete abstinence from exercise in eating disorder populations, but recent guidelines advocate for the gradual inclusion of healthier forms of exercise into an overall treatment plan where appropriate. Given the association between problematic exercise behaviour and poorer prognosis, there has been a recent upsurge in the number of treatment interventions for compulsive exercise in eating disorders. However, no systematic review has been published summarising this existing treatment literature. The aim of this review is to determine the efficacy of existing treatments for compulsive exercise in eating disorders and muscle dysmorphia.

METHODS

A systematic review will be conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Five electronic databases (PsycInfo, MEDLINE, Embase, Web of Science, and Scopus) will be searched from database inception until November 2020. We will include studies that: (a) sampled adolescents and/or adults with either an eating disorder or muscle dysmorphia; (b) assessed changes in compulsive exercise from pre- to post-intervention; and (c) used a standardised instrument to measure compulsive exercise or related constructs. We will include studies with a comparison group (e.g., randomised controlled trials) and without a comparison group (e.g., pilot studies and case studies) to provide a comprehensive overview of the literature. One reviewer will screen all titles and abstracts against eligibility criteria, with 20% of excluded articles cross-referenced by another reviewer. Full texts will be obtained for articles deemed relevant or where inclusion was uncertain, and will be screened by both reviewers. We will also evaluate the quality of the included studies using a modified Downs and Black (J Epidemiol Community Health 52:377-384, 1998) assessment checklist.

DISCUSSION

Results from this review will help to determine the most efficacious treatment components for compulsive exercise in eating disorders and muscle dysmorphia. We hope that our results will help inform clinical practice guidelines in recommending targeted interventions for the treatment of compulsive exercise.

Development and evaluation of an adapted physical activity program in anorexia nervosa inpatients: A pilot study

BACKGROUND AND CONTEXT

Problematic use of physical activity is frequent in subjects with anorexia nervosa (AN). Although it increases resistance to therapeutic treatment, paradoxically, physical activity in AN can also improve mental and physical health. Based on the literature review we hypothesized that adding an adapted physical activity (APA) program to treatment programs could be more beneficial than a total suppression of physical activities. We designed this open study to evaluate the outcome of AN inpatients after an APA program implementation as well as the perceived effect of APA.

METHOD

Forty-one women with AN (17.2 (±2.5) years old, BMI of 16.86 (±2.0)) were included. An eight-session (1 h30/session/week) standardized APA program was delivered and evaluated by structured questionnaires assessing exercise dependence, perceived physical activity, eating disorder (ED) symptoms, body mass index (BMI), along with an interview before and after the APA program.

RESULTS

Twenty-nine women complete the PA program and evaluation. BMI and perceived PA score significantly increased, ED and exercise dependence scores significantly decreased (p < .01). Participants appreciated the program.

DISCUSSION/CONCLUSION

The inpatient program which included APA program helped AN inpatients in decreasing their ED symptoms and their dependence to PA, without any deleterious effect on BMI. Furthermore, APA was appreciated by participants.

High-intensity exercise is associated with a better nutritional status in anorexia nervosa

OBJECTIVE

Our aim is to investigate the links between duration and intensity of exercise and the nutritional status in terms of body composition in acute anorexia nervosa (AN) patients.

METHOD

One hundred ninety-one hospitalized women suffering from AN were included. Exercise duration and intensity were assessed using a semistructured questionnaire. Body composition was measured using bioelectrical impedance. Linear multiple regression analyses were carried out using body mass index, fat-free mass index, and fat mass index as dependent variables and including systematically exercise duration, exercise intensity, and other confounding variables described in the literature that were significantly associated with each dependent variable in univariate analysis.

RESULTS

A lower BMI was linked to lower exercise intensity, AN restrictive type, and presence of amenorrhea. A lower FFMI was linked to lower exercise intensity, older age, AN restrictive type, and premenarchal AN. Duration of exercise was not linked to the nutritional status.

CONCLUSIONS

Exercising at higher intensity in AN is associated with a better nutritional status, thus, a better resistance to starvation. The impact of therapeutic physical activity sessions, adapted in terms of exercise intensity and patient's clinical status, should be evaluated during nutrition rehabilitation.

Is abstinence really the best option? Exploring the role of exercise in the treatment and management of eating disorders

Exercise prescription is suggested to help manage exercise abuse and improve overall eating disorder (ED) prognosis. This study explored emerging perceptions of ED health professionals concerning the role of exercise as a supportive treatment for EDs. Semi-structured interviews were conducted with international health professionals (n=13) with expertise in ED treatment. Verbatim transcripts were analyzed through thematic analysis. Four themes were revealed and titled 1) understanding the current state; 2) gaining perspectives; 3) barriers and benefits; 4) one size does not fit all. Within these themes, participants described the current state of exercise in ED treatment and suggested there exists a gap in research knowledge and practice. Participants also identified the implications of incorporating exercise into treatment and how an exercise protocol may be designed. Results enhance the understanding of the role of exercise in ED treatment and how it may further benefit individuals with EDs.

How to integrate physical activity and exercise approaches into inpatient treatment for eating disorders: fifteen years of clinical experience and research

BACKGROUND

The importance of physical activity and exercise among patients with eating disorders (EDs) is acknowledged among clinicians and researchers. The lack of clinical guidelines, the differing attitudes towards exercise approaches in treatment, and the lack of specialized competence all influence the management of ED symptoms in specialist ED treatment units. The purpose of the study was to examine 15 years of clinical experience with exercise approaches as an integrated part our inpatients treatment program.

METHODS

From January 2003 to December 2017, 244 patients were admitted to a specialist ED unit in Norway. The treatment program at the ED unit is multidisciplinary. It is based on psychodynamic theory, and designed to enhance patients' recovery and to enable them to adopt a lifestyle that is as healthy as possible. The authors describe the clinical management of patients with reference to practical examples and a case example.

RECOMMENDATIONS AND EXPERIENCE

The treatment for exercise is not manualized, but adjusted to the specific symptoms and needs of individual ED patients. The treatment approaches to exercise are part of the body-oriented treatment at the Specialist eating disorder unit (Regionalt kompetansesenter for spiseforstyrrelser (RKSF)), and the therapy addresses the entire body and the relation between the body, emotions, and the patient's social situation. It covers a chain of approaches from admission to discharge, from rest and relaxation to regular exercise groups.

CONCLUSIONS

Our experience and recommendations support earlier proposals for treatment approaches to exercise and exercise-related issues as a beneficial supplement to the treatment of ED inpatients. We have not experienced any adverse influences on patients' recovery processes, such as their rate of weight gain. Our intention is that this paper will be a contribution to the field of ED, the integration of exercise approaches in the inpatient treatment of ED and development of clinical guidelines.

Exercise in Eating Disorders Treatment: Systematic Review and Proposal of Guidelines

INTRODUCTION

Although exercise is an effective intervention for many psychological health issues, it has often been overlooked as a potential adjunct to eating disorder (ED) treatment. Thus, our objective was to summarize the literature by synthesizing themes identified in clinical studies and explicit guidelines or recommendations for the use or management of exercise in ED interventions into a proposed set of guidelines for the use of exercise in ED treatment.

METHODS

A literature search in exercise science, health psychology, and the ED literature was conducted. The focus was to obtain articles that reported on therapeutic effects and/or guidelines for the therapeutic use of exercise in individuals with ED.

RESULTS

Our review identified 11 core themes describing techniques that have been successful in using exercise therapeutically in ED treatment. These 11 guidelines are as follows: employ a team of relevant experts, monitor medical status, screen for exercise-related psychopathology, create a written contract of how therapeutic exercise will be used, include a psychoeducational component, focus on positive reinforcement, create a graded exercise program, begin with mild-intensity exercise, tailor the mode of exercise to the needs of the individual, include a nutritional component, and debrief after exercise sessions.

CONCLUSION

Our review identifies specific guidelines that may enhance ED treatment outcomes. It is the first to summarize divergent literature and synthesizes previous successes that may guide the use of therapeutic exercise in some, but not all ED patients. This review provides a practical set of guidelines for the clinical management and therapeutic use of exercise in ED treatment by focusing on empowering individuals with exercise as a tool for healthy living.

The assessment and treatment of unhealthy exercise in adolescents with anorexia nervosa: A Delphi study to synthesize clinical knowledge

This study aimed to explore and synthesize expert clinical knowledge on defining and managing unhealthy exercise in adolescents with AN. The Delphi methodology was used. Clinicians (n = 25) considered experts in the treatment of AN in adolescents were recruited internationally to form the panel. The first round of the questionnaires was comprised of five open-ended questions regarding defining, assessing, and treating unhealthy exercise in adolescents with AN. Statements were derived from this data using content analysis, and included as Likert-based items in two subsequent rounds, in which panellists were required to rate their level of agreement for each item. All 25 respondents completed the three rounds of questionnaires. Consensus was achieved for 59.0% of the items included in the second and third round of questionnaires. Although consensus was not achieved, compulsive exercise was the preferred term for the panel when referring to unhealthy exercise in adolescents with AN. The panel clearly delineated features of unhealthy and healthy exercise, and endorsed a number of items considered important to assess for when evaluating exercise in this clinical population. A variety of treatment approaches and strategies reached consensus. Notably, for those who are medically stable and progressing toward recovery, the panel recommended initial exercise restriction practices and reintroducing healthy exercise behaviors, rather than exercise cessation practices. The current findings can serve as preliminary treatment guidelines. A unified approach to labeling and defining unhealthy exercise in the eating disorder literature and clinical settings is required to achieve further progress.

Behavioral and psychological aspects of exercise across stages of eating disorder recovery

This study examined the relationship between behavioral and psychological aspects of exercise and eating disorder recovery. Participants were categorized as having an eating disorder (n = 53), partially recovered (n = 15), fully recovered (n = 20), or non-eating disorder controls (n = 67). Groups did not differ significantly in time spent exercising, but did differ in exercise intensity, guilt-related exercise, obsessive exercise cognitions, and appearance/weight management and stress/mood management motivations for exercise. Results support the importance of measuring psychological aspects of exercise in particular across the course of an eating disorder.

Impact of female adult eating disorder inpatients' attitudes to compulsive exercise on outcome at discharge and follow-up

BACKGROUND

The link between compulsive exercise and eating disorders is well known, but research with clinical samples has been limited. The purpose of the study was to investigate changes in attitudes towards compulsive exercise and its impact on outcome at follow-up in female adult hospitalised patients with eating disorders.

METHODS

The sample consisted of 78 patients: Diagnostic distribution: anorexia nervosa 59 % (n = 46), approximately 22 % (n = 16) in bulimia nervosa, and Eating Disorder not Otherwise Specified respectively. The average follow-up period was 26 months (SD =15 months). Compulsive exercise was measured by the Exercise and Eating Disorder (EED) questionnaire. Other measures were the Eating Disorder Inventory (EDI-2), Body Attitude Test (BAT), Symptom Checklist (SCL-90), Inventory of Interpersonal Problems (IIP 64), Beck Depression Inventory (BDI), and body mass index (BMI). Outcome measures were EDI-2 and BMI (patients with admission BMI ≤ 18.5). Paired sample t-tests and mixed model regression analysis were conducted to investigate changes in compulsive exercise and predictors of outcome respectively.

RESULTS

All measures revealed significant improvements (p < .01 - p < .001) from admission to follow-up. EED scores significantly predicted changes in EDI-2 scores and BMI (p < .01 and p < .001 respectively). Other significant predictors were BAT, SCL-90, IIP-64, BMI (p < .01-.001) (EDI-2 as outcome measure), and BAT and BDI (p < .001) (BMI as outcome measure).

CONCLUSIONS

The results demonstrated significant improvements in attitudes towards compulsive exercise during treatment and follow-up. The change in compulsive exercise scores predicted the longer-term course of eating disorder symptoms and BMI.

A perfect storm: examining the synergistic effects of negative and positive emotional instability on promoting weight loss activities in anorexia nervosa

Growing evidence indicates that both positive and negative emotion potentially influence the development and maintenance of anorexia nervosa, through both positive and negative reinforcement of weight loss activities. Such reactive emotional experience may be characterized by frequent and intense fluctuations in emotion, a construct known as "emotional instability." The purpose of this study was to investigate the association between positive emotional instability and weight loss activities in anorexia nervosa, and to investigate the synergistic effects of positive and negative emotional instability on promoting weight loss activities. Using ecological momentary assessment methods, 118 participants with anorexia nervosa reported their emotional experiences and behaviors at least six times daily over 2 weeks using a portable digital device. Using generalized linear modeling, results indicated that high levels of both positive and negative emotional instability, and the interaction between the two, were associated with more frequent weight-loss activities, beyond anorexia subtype and mean levels of emotional intensity. These findings indicate that when women with anorexia exhibit both high levels of both positive and negative emotional instability they are more prone to a variety of weight loss activities. The importance of addressing the role of both positive and negative emotion in anorexia treatment is discussed.

High Levels of Physical Activity in Anorexia Nervosa: A Systematic Review

High level physical activity is a frequent symptom in patients with anorexia nervosa (AN), influencing the development, maintenance, complications, treatment success, relapse rate and severity of the disease. Accelerometry is assumed to be an objective method to assess physical activity (PA) in AN. We aimed to review objectively measured levels of PA in AN and to give an overview for clinical practice and future research. Data were searched in PubMed and PsychINFO until April 2015 following the preferred reporting items for systematic reviews and meta-analyses statement. Twenty studies fulfilled the inclusion criteria. A notable heterogeneity of measurements, outcomes, participants and settings was found. Overall, HLPA is not adressed enough by current evidence. A common valid terminology of HLPA is not available, and accurate criteria of different levels of PA must be defined to create comparability of future studies. Further objective PA assessments are needed to improve treatment outcome and relapse rate.

Enlargement of Axo-Somatic Contacts Formed by GAD-Immunoreactive Axon Terminals onto Layer V Pyramidal Neurons in the Medial Prefrontal Cortex of Adolescent Female Mice Is Associated with Suppression of Food Restriction-Evoked Hyperactivity and Resilience to Activity-Based Anorexia

Many, but not all, adolescent female mice that are exposed to a running wheel while food restricted (FR) become excessive wheel runners, choosing to run even during the hours of food availability, to the point of death. This phenomenon is called activity-based anorexia (ABA). We used electron microscopic immunocytochemistry to ask whether individual differences in ABA resilience may correlate with the lengths of axo-somatic contacts made by GABAergic axon terminals onto layer 5 pyramidal neurons (L5P) in the prefrontal cortex. Contact lengths were, on average, 40% greater for the ABA-induced mice, relative to controls. Correspondingly, the proportion of L5P perikaryal plasma membrane contacted by GABAergic terminals was 45% greater for the ABA mice. Contact lengths in the anterior cingulate cortex correlated negatively and strongly with the overall wheel activity after FR (R = -0.87, P < 0.01), whereas those in the prelimbic cortex correlated negatively with wheel running specifically during the hours of food availability of the FR days (R = -0.84, P < 0.05). These negative correlations support the idea that increases in the glutamic acid decarboxylase (GAD) terminal contact lengths onto L5P contribute toward ABA resilience through suppression of wheel running, a behavior that is intrinsically rewarding and helpful for foraging but maladaptive within a cage.

The therapeutic process in psychological treatments for eating disorders: a systematic review

OBJECTIVE

For eating disorders, a vast number of investigations have demonstrated the efficacy of psychological treatments. However, evidence supporting the impact of therapeutic process aspects on outcome (i.e., process-outcome research) has not been disentangled.

METHOD

Using the Generic Model of Psychotherapy (GMP) to organize various process aspects, a systematic literature search was conducted on psychological treatment studies for anorexia nervosa, bulimia nervosa, binge-eating disorder, and eating disorders not otherwise specified.

RESULTS

Improved outcomes resulted for family-based treatment compared to individual treatment, for individual compared to group treatment, booster sessions, and positive patient expectations (GMP contract aspect); for nutritional counseling and exercising but not exposure with response prevention as adjunct interventions (therapeutic operations); for highly motivated patients and, to a lesser extent, for therapeutic alliance (therapeutic bond); as well as for rapid response and longer overall treatment duration (temporal patterns). Regarding other GMP aspects, studies on self-relatedness were completely lacking and in-session impacts were rarely investigated.

DISCUSSION

As most studies assessed only a limited number of process aspects, the ability to draw conclusions about their overall impact regarding outcome is rather limited. Therefore, future process-outcome research is needed beyond investigations of treatment efficacy for eating disorders.

Nothing Tastes as Good as Thin Feels: Low Positive Emotion Differentiation and Weight Loss Activities in Anorexia Nervosa

Positive emotion (PE) has not been well studied in anorexia nervosa. Low positive emotion differentiation (PED), which involves a diminished ability to distinguish between discrete positive emotions, may contribute to positive emotion dysregulation in anorexia. Specifically, low PED may interact with elevated PE intensity to both motivate and reinforce weight loss and evaluation behaviors. Using ecological momentary assessment, we examined PE and weight loss behaviors reported over two weeks. As hypothesized, low PED predicted more vomiting, laxative-use, exercising, weighing, checking for fat, and restricting. Furthermore, those with low PED who experienced elevated average PE intensity reported even more frequent behaviors. Within-person analyses indicated that, for those with low PED, more weight loss behaviors at one recording predicted elevated PE at the subsequent recording. Similarly, for those with low PED higher momentary PE predicted more subsequent weight loss behaviors. Thus, low PED in anorexia may reinforce and motivate weight loss behavior.

Eating disorders, physical fitness and sport performance: a systematic review

Background: Eating disorders are health problems that are particularly prevalent in adolescents and young adults. They are associated with considerable physical health and psychosocial morbidity, and increased risk of mortality. We set out to conduct a systematic review to determine their effect on physical fitness in the general population and on sport performance in athletes. Methods/Design: A systematic review of the relevant peer-reviewed literature was performed. For inclusion, articles retrieved from PubMed had to be published in English between 1977 and 2013. Wherever possible, methods and reporting adhere to the guidelines outlined in the PRISMA statement. Some additional studies were retrieved from among those cited in the reference lists of included studies and from non-electronic databases. Literature searches, study selection, method and quality appraisal were performed independently by two authors, and data was synthesized using a narrative approach. Results: Of the 1183 articles retrieved, twenty-nine studies met the inclusion criteria and were consequently analysed. The available data indicate that eating disorders have a negative effect on physical fitness and sport performance by causing low energy availability, excessive loss of fat and lean mass, dehydration, and electrolyte disturbance. Discussion: Although the paucity of the available data mean that findings to date should be interpreted with caution, the information collated in this review has several practical implications. First, eating disorders have a negative effect on both physical fitness and sport performance. Second athletics coaches should be targeted for education about the risk factors of eating disorders, as deterioration in sport performance in athletes, particularly if they are underweight or show other signs of an eating disorder, may indicate the need for medical intervention. However, future studies are needed, especially to assess the direct effect of eating disorders on sport performance.

A systematic review of physical therapy interventions for patients with anorexia and bulemia nervosa

PURPOSE

The purpose of this systematic review was to summarise the evidence from randomised controlled trials examining the effectiveness of physical therapy compared with care as usual or a wait-list condition on eating pathology and on physiological and psychological parameters in patients with anorexia and bulimia nervosa.

METHOD

EMBASE, PsycINFO, PubMed, Cumulative Index to Nursing and Allied Health Literature, Physiotherapy Evidence Database and The Cochrane Library were searched from their inception until February, 2013. Articles were eligible if they utilised a randomised controlled trial design, compared physical therapy with a placebo condition, control intervention, or standard care and included patients with anorexia and bulimia nervosa. The methodological quality was assessed with the Jadad scale.

RESULTS

Eight randomised controlled trials involving 213 patients (age range: 16-36 years) met all selection criteria. Three of the 8 included studies were of strong methodological quality (Jadad score≥3). Major methodological weaknesses were attrition and selection bias. The main results demonstrate that aerobic and resistance training result in significantly increased muscle strength, body mass index and body fat percentage in anorexia patients. In addition, aerobic exercise, yoga, massage and basic body awareness therapy significantly lowered scores of eating pathology and depressive symptoms in both anorexia and bulimia nervosa patients. No adverse effects were reported.

CONCLUSIONS

The paucity and heterogeneity of available studies limits overall conclusions and highlights the need for further research. Implications for Rehabilitation Supervised physical therapy might increase weight in anorexia nervosa patients. Aerobic exercise, massage, basic body awareness therapy and yoga might reduce eating pathology in patients with anorexia and bulimia nervosa. Aerobic exercise, yoga and basic body awareness therapy might improve mental and physical quality of life in patients with an eating disorder.

Exercise and physical activity in mental disorders: clinical and experimental evidence

Several epidemiological studies have shown that exercise (EX) and physical activity (PA) can prevent or delay the onset of different mental disorders, and have therapeutic benefits when used as sole or adjunct treatment in mental disorders. This review summarizes studies that used EX interventions in patients with anxiety, affective, eating, and substance use disorders, as well as schizophrenia and dementia/mild cognitive impairment. Despite several decades of clinical evidence with EX interventions, controlled studies are sparse in most disorder groups. Preliminary evidence suggests that PA/EX can induce improvements in physical, subjective and disorder-specific clinical outcomes. Potential mechanisms of action are discussed, as well as implications for psychiatric research and practice.

Is supervised exercise training safe in patients with anorexia nervosa? A meta-analysis

BACKGROUND

Anorexia nervosa is an eating disorder that is often preceded by excessive physical activity. As such, exercise is not often prescribed in the clinical management of individuals with anorexia nervosa.

OBJECTIVE

To examine the effects of supervised exercise training in patients with anorexia nervosa.

DATA SOURCES

Five databases were searched from their inception to Week 14 of 2011 using the subject headings 'anorexia' and 'exercise' to identify relevant studies.

ELIGIBILITY CRITERIA

PRISMA guidelines were followed. Studies that investigated the effects of inclusion of supervised exercise training in clinical management with usual management in patients diagnosed with anorexia nervosa were included in this review. Case reports were excluded.

DATA EXTRACTION AND SYNTHESIS

Two reviewers independently extracted data using a standardised assessment form. Quality assessment was rated for the controlled trials and single-group studies using the PEDro scale and Downs and Black scale, respectively. Fixed or random effect approaches were used to determine effect size, depending on the heterogeneity of the studies.

RESULTS

Pooled randomised controlled trials and quasi-randomised studies showed no significant effect of supervised exercise training on selected anthropometric measurements, while the single-group studies showed significant improvement in weight and body fat. Although Short Form-36 revealed no training effect, distorted feelings about food and exercise were reduced. Cardiovascular fitness also improved with no decrease in weight.

LIMITATIONS

Heterogeneity of exercise training programmes, small sample size (n≤20) for 67% of the trials, and inability to exclude publication bias.

CONCLUSIONS

Inclusion of supervised exercise training in the comprehensive management of patients with anorexia nervosa appears to be safe, as no detrimental effect was observed in anthropometry. Strength and cardiovascular fitness were also shown to improve.

Exercise and physical activity in mental disorders

Exercise (EX) and physical activity (PA) have been shown to prevent or delay the onset of several mental disorders and to have therapeutic effects in different groups of psychiatric disorders. This review focuses on studies investigating EX as therapeutic intervention in anxiety disorders, affective disorders, eating disorders, schizophrenia, and substance use disorders. Despite EX being discussed as a potential therapy for several decades, adequately powered randomized, controlled trials are sparse in most disorder groups. Nevertheless, evidence points toward disorder-specific benefits that can be induced by EX/PA. Mechanisms of the therapeutic effects of EX/PA are summarized, including metabolic and physiological as well as psychological aspects. Finally, implications for research and therapeutic practice are illustrated.