Work

Cutoff values of muscle-specific strength using arm circumference: Results from NHANES 2011-2014

Year: 2026

Type: article

Abstract: BACKGROUND: Muscle-specific strength, the ratio of muscle strength to muscle mass, reflects functional capacity and has been incorporated into contemporary conceptual definitions of sarcopenia, although its operational diagnostic role remains undefined. Ideally, muscle-specific strength relates muscle strength to the mass of the muscles that generate it; however, such measures are rarely available in clinical practice. Mid-upper arm circumference (MUAC) may serve as a practical regional surrogate for muscle mass. OBJECTIVES: To examine the relationship between conventional muscle-specific strength from dual-energy X-ray absorptiometry (DXA) and a MUAC-based muscle-specific strength, and to propose sex-specific cutoff values for the latter. METHODS: ) served as the reference subsample. Survey-weighted Pearson correlations and linear regression models were used to examine relationships between MUAC- and DXA-based muscle-specific strength. Cutoff values were derived at 1 and 2 standard deviations (SD) below the survey-weighted sex-specific reference mean. Bland-Altman analyses assessed agreement between the two metrics after transformation to sex-specific standardized scores. RESULTS: lean soft tissue in males (r = 0.80) and females (r = 0.74). MUAC-based muscle-specific strength was also strongly correlated with DXA-based muscle-specific strength in males (r = 0.79) and females (r = 0.72). Associations between the two metrics remained significant after adjustment for age, race and ethnicity, and BMI. Rounded cutoff values for MUAC-based muscle-specific strength were <1.3 kg/cm for low and <1.0 kg/cm for very low values in males. In females, the corresponding cutoff values were <0.9 kg/cm for low and <0.8 kg/cm for very low muscle-specific strength. Exploratory Bland-Altman analyses showed small mean differences between the standardized metrics (0.14 SD in males and -0.02 SD in females), although the 95% limits of agreement indicated individual variability (-1.12 to 1.40 SD in males and -1.79 to 1.74 SD in females). CONCLUSION: Our study provides practical, sex-specific reference cutoff values for MUAC-based muscle-specific strength (HGS/MUAC) derived from a population-based sample. This accessible anthropometric metric showed strong correlations with DXA-based muscle-specific strength and small average standardized differences, supporting its potential as a pragmatic surrogate when regional body composition assessment is unavailable. Further validation is needed before its clinical or diagnostic application.

Source: Clinical Nutrition ESPEN

DOI: 10.1016/j.clnesp.2026.105235