The purpose of this study is to clarify the effect of hip, knee, and ankle joint contractures on the joint angle and joint moment during standing posture using a mechanics simulation. A two-dimensional segment model (trunk, thighs, shanks, and feet) was created, and the standing postures for various hip, knee, and ankle joint angle configurations were generated (i.e. 743 types of standing postures). The hip, knee, and ankle joint contractures were reproduced by manipulating the joint stiffness, and optimal standing posture when the minimum value of the sum of muscle activities was obtained. When the hip joint contracture was developed during standing posture, the hip and knee flexion angle, and the hip and knee extension moment increased as well. When the knee joint contracture was developed during standing posture, the hip and knee flexion angle, ankle dorsiflexion angle, and the knee extension moment increased. When the ankle joint contracture was developed during standing posture, the hip flexion angle and the ankle plantarflexion angle increased and the knee joint was extended; the hip extension moment and knee flexion moment also increased. The findings of this study may help to improve abnormal standing posture through physical therapy.

This study examined whether physical and cognitive function was independently associated with risk of Musculoskeletal Ambulation Disorder Symptom Complex (MADS) in community-dwelling older people. We examined 640 older people (315 men, 325 women; 65–89 years). We assessed physical performance by one-leg standing with eyes open, timed up and go (TUG), muscle strength, muscle power, and gait speed. Cognition was assessed using Mini-Mental State Examination (MMSE), Clinical Dementia Rating (CDR), and Trail-Making Tests (TMT) A and B. We divided participants by physical function into “MADS” (one-leg standing < 15s or TUG ≥ 11s) and “non-MADS”, and identified cognitive impairment if MMSE was < 27 and CDR ≥ 0.5. We also grouped by sex and age (younger-old: 65–74 years and older-old: 75–89 years), and controlled for age, Body Mass Index, education and steps. Physical and cognitive function was significantly worse in the MADS groups. The younger-old men had poorer muscle strength, muscle power and TMT-A. The younger-old women had poorer muscle power, gait speed, MMSE and TMT-B. Older-old men had poorer muscle strength, and older-old women poorer gait speed (P < 0.05). The MADS groups also had significantly higher adjusted odds ratio (OR) for cognitive impairment (younger-old men: OR: 4.62; 95% confidence interval [CI]: 1.08–19.8; younger-old women: OR: 6.09; 95% CI: 1.03–35.9; P < 0.05). This study suggested that poorer physical and cognitive function was significantly associated with the risk of MADS, and these associations may be differ with sex and age.

Habitual exercise is important for improving or maintaining the arterial function with age. However, the role of functional fitness on arterial stiffness in the elderly is unclear. This study was conducted to examine the relationships between functional fitness and arterial stiffness in elderly woman. Four hundred and seventy-nine elderly woman participated in the present investigation. The systolic/diastolic blood pressure and brachial to ankle pulse wave velocity were obtained in the supine position using an automatic pulse wave form analyzer. Four items of functional fitness (standing/sitting, walking, hand working, and self-care working) were assessed. The measurement variables were calculated for five chronological classifications (60~64, 65~69, 70~74, 75~79 and 80 yrs or over). The four items of functional fitness and brachial to ankle pulse wave velocity increased linearly with age. A multiple stepwise regression analysis revealed that systolic blood pressure (β= 0.366), age (β= 0.225), heart rate (β= 0.188), body mass index (β= -0.102), and standing/sitting (β= 0.098) were independent contributors to brachial to ankle pulse wave velocity, accounting for 29.6% of the variability. The physical function, especially standing/sitting, influences the arterial function in elderly women.