## 4 Discussion  
Age-related sarcopenia significantly compromises walking stability and increases the risk of falls, thereby elevating the incidence of accidental death among the elderly population. Consequently, this study aims to investigate the relationship between skeletal muscle characteristics and specific gait parameters in older adults aged 75 and over afflicted by conditions such as muscle mass decline, poor physical performance, and sarcopenia. Among the participants, 21.9% were classified as normal (mean age: 78.1 years), while 28.5% exhibited muscle mass decline (mean age: 78.1 years), 26.4% demonstrated poor physical performance (mean age: 80.1 years), and 23.1% were identified with sarcopenia (mean age: 80.2 years). In this study, individuals with decreased physical performance or sarcopenia showed lower levels of fall efficacy (FEC) and balance self-efficacy (ABC) along with distinct gait parameter characteristics among the low MM, poor PP, and sarcopenia groups. Specifically, individuals with poor PP and sarcopenia demonstrated shorter double-limb stances, shorter stride lengths, and greater variability in gait speed and stride length compared to the normal or low MM groups. Notably, the combined model of gait speed and double-limb stance showed higher accuracy in predicting sarcopenia. In line with prior research, our study also highlights a significant correlation between age and sarcopenia, indicating that as individuals age, the risk of sarcopenia, coupled with muscle weakness, escalates [18,19]. A decline in muscle function (or strength) has been linked to compromised lower extremity function [20], mobility limitations [21], decreased independence in activities of daily living [22], and diminished health-related quality of life [23,24] among older adults. Thus, the early detection of muscle strength decline and sarcopenia in the elderly is crucial for effectively mitigating the occurrence of falls, disabilities, and mortality, necessitating \begin{table}
\begin{tabular}{c c c c c} \hline \hline  & **AUC (95\% CI)** & \(p\) **Value** & **Sensitivity** & **Specificity** \\ \hline Gait speed + double-limb stance & 0.702 (0.622–0.781) & \textless{}0.001 & 78.9\% & 76.3\% \\ \hline \hline AUC: area under the curve; 95\% CI: 95\% confidence interval. & & & \\ \hline \end{tabular}
\end{table} 
Table 6: Receiver operating characteristic (ROC) curve for sarcopenia: the new model (gait speed + double-limb stance). Figure 3: The ROC curve for sarcopenia prediction: A new model (gait speed + double-limb stance rate) noticeably improved the AUC. ROC: receiver operating characteristic; AUC: area under the ROC curve. the immediate implementation of preventive measures such as physical activity, nutrition, and medical interventions. Age-related changes in gait parameters encompass reductions in gait speed, stride length, stride width, and double-limb stance rate. Previous studies consistently demonstrated a positive correlation between muscle strength and gait speed [25; 26]. Slower gait speed has consistently been linked to a higher risk of falls, hospitalization, and mortality, particularly among older adults with low muscle mass, compromised physical performance, and sarcopenia [27; 28; 29]. Similar to earlier findings, this study did not confirm the relationship between muscle mass and gait speed. However, a significant correlation was observed between physical performance and sarcopenia [26]. This suggests that muscle function impacts gait speed, while muscle mass does not. A decline in muscle mass alongside a decrease in gait speed or mobility impairment is believed to be associated with aging [29]. Despite the continued influence of sarcopenia on gait speed, it is established that slow gait speed is linked to the occurrence of sarcopenia [30; 31]. In addition to our findings, [PERSON] et al.