Physical activity and post‐treatment weight trajectory in anorexia nervosa

Abstract

Objective-This study compared an objective measurement of physical activity (PA) in individuals with anorexia nervosa (AN) at low-weight, weight-restored, and post-treatment time points, and also compared PA in AN with that of healthy controls (HC).Method-Sixty-one female inpatients with AN wore a novel accelerometer (the IDEEA) which measured PA at three time points: a) low-weight, b) weight-restored, and c) one month posthospital discharge. Twenty-four HCs wore the IDEEA at one time point.Results-Inpatients with AN became more physically active than they were at low-weight at weight restoration and following treatment discharge. Post-treatment patients with AN were more physically active than HCs during the day and less active at night, which was primarily accounted for by amount of time spent on feet, including standing and walking. Greater time spent on feet during the weight-restoration time point of inpatient treatment was associated with more rapid decrease in BMI over the 12 months following treatment discharge. Fidgeting did not differ between patients and controls, did not change with weight restoration, and did not predict posttreatment weight change.Discussion-Use of a novel accelerometer demonstrated greater PA in AN than in healthy controls. PA following weight restoration in AN, particularly time spent in standing postures, may contribute to weight loss in the year following hospitalization. Keywords Author Manuscript Author ManuscriptAuthor Manuscript Author ManuscriptAnorexia Nervosa (AN) is a serious psychiatric illness marked by self-starvation and overvaluation of shape and weight. There has been a longstanding interest in the role of physical activity (PA) in the etiology, maintenance, and prognosis of AN. A range of methods has been used to assess PA in AN, from subjective patient report of exercise frequency and drive to exercise, to objective devices such as accelerometers, which can quantify the frequency and duration of PA.Despite low weight, a significant subset of individuals with AN report that they engage in "excessive" or "compulsive" exercise (1), with one of the earliest clinical observations of a patient with AN by Dr. William Gull from 1868 noting that despite extremely low weight, the patient was "restless and active...it seemed hardly possible that a body so wasted could undergo the exercise which seemed agreeable"(2). This elevated level of exercise is associated with heightened psychopathology, such as depression, anxiety, and eating disorder symptomatology (3-6). Compulsive exercise during treatment is also negatively associated with improvements in eating disorder pathology by treatment discharge (3) and subjective report of compulsive exercise is associated with long-term lack of recovery from AN (7).Notwithstanding the longstanding clinical observation of heightened PA in AN, investigation of objective activity levels in patients with AN has yielded mixed results. While some studies have found that patients with AN are more active than healthy controls (8), oth...

Measurement of fidgeting in patients with anorexia nervosa using a novel shoe-based monitor

“…SmartShoe has shown greater sensitivity to movement while seated, or “fidgeting”, relative to a 5-site activity sensor (IDEEA) apparatus (Klein et al, 2014), which was used to assess this behavior in the past (Gianini et al, 2016). …”

“…These activities are receiving greater attention in the study of AN, as little is known about their role in weight regulation, metabolism, and psychopathology. While patients with AN have been found to spend more time on their feet after treatment, and take more steps per day than healthy controls, (El Ghoch et al, 2013; Gianini et al, 2016) clinical understanding of fidgeting is less clear. Clinicians often report elevated levels of this behavior among patients, although objective assessment using a 5-site, wire-based activity monitorhas found no significant difference in fidgeting between patients and HCs (Gianini et al, 2016).…”

Moving beyond self‐report data collection in the natural environment: A review of the past and future directions for ambulatory assessment in eating disorders

“…Physical activity was indexed in a variety of ways, including average daily activity in terms of energy expenditure, mean counts per minute or day, total minutes of light, moderate, and vigorous activity, as well as counts per minute in peak activity. Three studies found no differences in objective physical activity between individuals with current or past anorexia nervosa and control groups (Bouten & Westerterp, ; Hechler et al, ; Keyes et al, ), whereas one study found that after treatment, individuals with anorexia nervosa were more active during daytime hours compared to controls (Gianini et al, ). One study of adolescents with anorexia nervosa found that physical activity levels stabilized over the course of treatment and at follow‐up assessment (i.e., those with high initial levels decreased activity, and those with low initial levels increased activity; Kostrzewa et al, ).…”

Exercise in Anorexia Nervosa: Complexity of Pathology and Health

“…It is beneficial also within domains defined by neurocognitive capacity, quality-of-life, postural and motor efficacy and affective status [16][17][18]. Generally, exercise has been defined as a planned, structured physical activity with the purpose of improving one or more aspects of physical fitness and functional capacity [19]. Health status may be estimated by the level of functional or metabolic efficiency of living organisms; in this context, the type, duration and extent of physical exercise may be an essential issue in determining its interventional status.…”