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

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.

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

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

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.

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.

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.

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

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.