Heart Rate Sensing and Response in Persons With Anorexia Nervosa

Inclusion Criteria: Study participants will include adults with anorexia spectrum disorders and healthy age and gender matched controls. There will be two control groups, one that includes regularly exercising age and gender matched persons and one where controls do not engage in regular exercise. For those with AN, the following INCLUSION criteria must be met: * Age ≥ 18 years old * BMI 25 kg/m2 or less * Diagnosis of anorexia spectrum disorder * Medications: Stable use of all medications ≥ three months For age and gender matched controls, the following INCLUSION criteria must be met: * Age ≥ 18 years old * BMI 25 kg/m2 or less * No diagnosis of anorexia spectrum disorder * Medications: Stable use of all medications ≥ three months * Age (+/- 2 years) and gender matched to study participant Exclusion Criteria: * History of diabetes, heart disease or taking medications for those conditions * History of hypertension (high blood pressure) not controlled with medication * Orthopedic limitations, musculoskeletal disease and/or injury * Inability to consent * Lack of transportation to the Duke Center for Living campus