Muscle strength may better predict bone health than body weight in a model of anorexia nervosa

Purpose: Mechanical force generated during muscle contractions plays a crucial role in regulating bone mass and strength. Consequently, muscle function may serve as a more accurate marker of skeletal health than body weight, particularly under energy-deficient conditions such as anorexia nervosa (AN). This study aimed to evaluate the relationship between muscle strength, body weight, and skeletal parameters during simulated AN and recovery. We hypothesized that muscle strength would more strongly predict skeletal health than body weight during AN and recovery. Methods: Female Sprague Dawley rats (8 weeks of age) were subjected to a simulated AN protocol involving a 50-60% food restriction for 30 days. After the restriction period, animals either underwent various durations of weight recovery-ranging from no recovery to 30 days-or served as healthy controls. Following designated interventions, parameters of muscle size, muscle strength, and skeletal health were evaluated. Total bone density was determined at the tibial region using peripheral quantitative computed tomography (pQCT). Bodyweight and muscle strength were correlated with total bone density. Results: Bodyweight showed an association with total bone density (r=0.47, p< 0.001). However, measures of muscle health demonstrated a seemingly stronger correlations with total bone density, including gastrocnemius mass (r =0.57, p< 0.001) and maximal plantar flexion force (r =0.55, p< 0.001). Conclusion: Muscle strength is a more reliable predictor of skeletal health than body weight during AN and subsequent weight restoration. Assessment of muscle strength may provide better insight into skeletal health in those with AN or in recovery from AN compared to bodyweight alone. Acknowledgements: This study was supported by NIH grant K12HD051959 (M.E.R.). This abstract was presented at the American Physiology Summit 2026 and is only available in HTML format. There is no downloadable file or PDF version. The Physiology editorial board was not involved in the peer review process.