Response to Acute Exercise in Eating Disorders

Inclusion Criteria:

• Aged 16-25

• ED participants must meet full criteria for DSM-5 restrictive-spectrum eatingdisorders characterized by weight and shape concern, I.e., anorexia nervosa (AN);mild, moderate, or in partial remission), atypical AN, and OSFED -AN type only)

• ED participants must be medically stable, and suitable for outpatient treatment

• Biological Females, Assigned Female at birth

• English Speaking

Exclusion Criteria:

• Those with a medical condition that precludes exercise (e.g., severe asthma) will beexcluded for any contraindications

• Biological Males, Assigned Male at birth

• BMI less than 16 (over 18 years) or less than 75% expected body weight (under 18 years)

• Reported intake on Eating Disorder Examination <1000kcal daily

• Current purging >1x per day

• Current regular episodes of objective binge eating (>1x/wk)

• Current self-report of loss-of control eating per the Eating DisordersExamination Interview

• ED related hospitalization, partial hospitalization, or residential treatmentin the past month

• Any endorsed medical concerns related to physical activity (as probed in thephone screening questions regarding cardiovascular, pulmonary, or metabolicdisease).

• Major medical disorders (e.g., cancer, AIDS)

• Physical discomfort or difficulty with blood draws

• Psychotic disorders

• Intellectual disabilities

• Developmental disorders

• Active substance use disorder

• Current suicidal risk per the Ask Suicide Screening Questionnaire

• Pregnancy

• Psychiatric medications that have not been stable for at least 4 weeks

• Acute sedatives / pain killers (e.g., benzodiazepines, opioids) andprescription stimulants (e.g., methylphenidate, amphetamines) are not permittedfor the full day prior to the laboratory session. The noted short-termmedication holds only apply to subjects taking the noted medications in casesused to treat ADHD or other psychiatric conditions

• Resting heart rate <50 beats per minute (assessed at screening visit)

• Low blood pressure (<90/60), (assessed at screening visit)

• Daily cannabis use

• History of light headedness or fainting during blood draws or physical activity

• History of chest pain during physical activity

• Bone, joint, cardiac, pulmonary, metabolic, or other medical conditions thatmay be worsened by physical activity (e.g., COPD, diabetes, hypertension) thatare not currently addressed via medication or lifestyle change.

• Physical disabilities that prohibit task performance (such as blindness ordeafness)

• Any other condition that the investigator believes might put the participant atrisk for negative outcomes

• Individuals with a restrictive eating disorder presentation that does notinclude weight and shape concern (ARFID) or that has primary binge eating (bulimia nervosa)

• Indication of health risk associated with exercise on the Physical ActivityReadiness Questionnaire