Publications

Myoton Clarification Note: A Guide to Interpreting the Inverse Relationship Between Logarithmic Decrement and Tissue Elasticity

This study examined sarcopenia severity effects on body composition, physical performance, and mechanical properties of gait-related muscles in older women.

Forty-one women aged ≥70 years participated and were classified by the following criteria: non-sarcopenia (NS, n = 15), functional sarcopenia (FS, n = 10), sarcopenia (SP, n = 9), and severe sarcopenia (SS, n = 7). Assessments included body composition, physical performance, and muscle tone, stiffness, and elasticity of the tibialis anterior (TA) and gastrocnemius medialis (GM). Group differences were analyzed using one-way ANOVA with Bonferroni post hoc tests (α = 0.05).

SP and SS groups had lower body weight, BMI, appendicular skeletal muscle mass, and calf circumference compared with NS. FS demonstrated poorer physical performance than SP across all variables, with six-meter gait speed lower than SS (p < 0.05). SP exhibited significantly higher TA muscle tone, GM muscle tone and GM stiffness than NS (p < 0.05, p < 0.01, p < 0.05, respectively), while TA elasticity was significantly lower in SP (p < 0.01).

These findings indicate that sarcopenia severity negatively influences body composition, muscle function, and mechanical properties, with functional sarcopenia showing the greatest impairment in performance. Early detection and targeted interventions are therefore critical to mitigate functional decline in older women.

Keywords: sarcopenia severity, physical performance, mechanical properties, older women

This study investigated the effects of sarcopenia severity on body composition, physical performance, and the mechanical properties of gait-related muscles in older women, offering preliminary evidence for exercise prescriptions tailored to different stages of sarcopenia.

First, older women with sarcopenia and severe sarcopenia showed greater deterioration in body composition and in the mechanical properties of gait-related muscles, specifically the tibialis anterior and gastrocnemius, compared with those with functional sarcopenia.

Second, functional sarcopenia was associated with more pronounced declines in physical performance than either sarcopenia or severe sarcopenia. It may be associated with adverse outcomes, and early diagnosis and timely exercise interventions are essential to prevent further decline. Importantly, these findings highlight that functional sarcopenia should not be underestimated, and that early intervention may be warranted even in the absence of muscle mass loss.

Finally, follow-up longitudinal studies are required to directly elucidate the associations over time and potential causal relationships in older adults with functional sarcopenia, which will provide more conclusive evidence.