For clinicians and patients navigating anorexia nervosa recovery, the invisible battle may matter as much as the visible one. A compulsive internal drive to move — even when no movement occurs — turns out to be a clinically significant feature of the disorder that current treatment frameworks largely ignore, and its presence during weight restoration may forecast who struggles most after discharge.
This PRISMA-compliant systematic review drew from 1,165 screened records across PubMed, Scopus, and EBSCOhost, ultimately synthesizing 17 studies that examined what researchers term the State Urge to be Physically Active (SUPA) in anorexia nervosa. Critically, SUPA is defined not as measurable movement but as an internal, compulsive urge — meaning it can remain clinically invisible while still driving pathology. The review found that elevated SUPA levels persisted independently of BMI changes, including during active recovery phases, and appeared to function primarily as a maladaptive emotion regulation mechanism rather than a stable personality trait. Most strikingly, higher SUPA intensity during weight restoration was associated with worse weight maintenance outcomes post-treatment.
The distinction between SUPA as a state versus a trait carries significant clinical weight. If the urge is contextually driven — activated by anxiety, emotional distress, or restriction — then targeting the underlying emotion dysregulation may be more therapeutically productive than addressing physical activity behavior directly. This reframes exercise restriction protocols, a common but contested clinical tool, as potentially insufficient without concurrent emotional regulation intervention. The 17-study inclusion is a limitation: the evidence base remains thin, with heterogeneous assessment tools and small samples, making effect size comparisons unreliable. Most studies also lack longitudinal follow-up beyond 12 months. Still, the finding that SUPA persists post-weight restoration elevates this from an incremental observation to a potentially paradigm-shifting one — suggesting recovery metrics anchored solely to BMI miss a neurobiologically active and prognostically meaningful dimension of the illness.