The High Precision of Functional and Neuromuscular Measures to Classify Sarcopenia in Older Women

Previous literature suggests that reductions in appendicular skeletal mass (ASM) may have a greater detrimental effect than total lean body mass regarding the onset and progression of sarcopenia. Unfortunately, limited access to equipment that accurately determines ASM often leads to many individuals remaining undiagnosed and experiencing functional decline. Therefore, the purpose of this investigation was to determine the ability of functional and neuromuscular measures to identify ASM in older women.

Forty-one (sarcopenic n = 15) older women underwent body composition analysis via dual-energy X-ray absorptiometry (DXA) and performed the following measures: bench press (BP) 1-repetition maximum strength (1RM), vertical jump height and power, handgrip strength, Timed Up and Go test, Berg Balance Scale testing, and bench press power testing at 20%, 40%, and 60% 1RM.

Regression analyses revealed 3 significant models accounting for 93.8%, 91.1%, and 86.4% of the variance in DXA-derived ASM. Paired-samples t tests revealed no significant differences between model-derived and DXA-derived ASM for each model, and each model was significantly correlated to DXA-derived ASM (P < .001). In addition, each model revealed a strong ability to appropriately classify sarcopenia status, with the area under the curve values ranging from 0.86 to 0.93. The present data indicate that ASM can be determined with high precision by measuring outcome variables such as jump power, body weight, and grip strength in older women.

Therefore, the present models could be used to identify, screen, or classify older women as sarcopenic, ultimately allowing the implementation of interventions aimed at decreasing the difficulty of activities of daily living and increasing quality of life.