Evaluation of Walking Ability of Elderly People Based on Detection of the Three-Dimensional Center of Gravity In Relation to the Sustainable Development Goals (SDG 3: Good Health and Well-Being)

Objective: This study was conducted to evaluate the walking capabilities of elderly people using the Detection of the Three-Dimensional Center of Gravity (D3DCG) method and to ascertain practical thresholds for walking aid recommendations. Theoretical Framework: Center of gravity mechanics, human balance control, and earlier D3DCG research are grounding principles. Earlier studies have applied D3DCG to young adults, with limited application to elderly populations. Theories of age-related decline in postural stability and fatigue-induced gait instability informed the experimental design. Method: The research included two complementary experiments. First, l/lmax and q/qmax values were measured using D3DCG when elderly daycare center participants walked on a flat surface. Here, l/lmax ​ represents the ratio of the actual height of the center of gravity to its maximum height, indicating postural stability, while q/qmax indicates the ratio of the actual lateral force to the critical lateral force, reflecting gait stability. A second comparison study was done to induce fatigue during observation of young adults walking on stairs, simulating elderly person-like gait instability. Patterns and thresholds were inferred from the analyzed data. Results and Discussion: Elderly participants had significantly higher q/qmax values. Those exceeding 0.9 were recommended to use walking aids. Those with greater than 1.0 were required to use them. Fatigued young participants exhibited similar q/qmax patterns, which validated the simulation approach. These results accord with theoretical expectations of balance deterioration attributable to aging and fatigue. Research Implications: The findings, which provide a quantitative basis for fall-risk assessment and walking aid recommendations in elderly care, demonstrate the method as applicable for preventive health, clinical, and rehabilitation contexts. Originality/Value: This report is the first of D3DCG application to actual elderly populations, introducing a threshold-based approach for walking aid recommendations with validation through comparison with fatigue-induced gait instability in young adults. This study contributes to the United Nations Sustainable Development Goal 3 (Good Health and Well-Being) by providing a quantitative and preventive method for fall-risk assessment among elderly populations.