Background: Uncontrolled manifold (UCM) analysis has been demonstrated as a useful tool to understand motor redundancy. Additionally, in this approach, variance in multi-degrees of freedom of the system is projected into variance that does not affect the performance variable (VUCM), and variance that affects it (VORT). A higher proportion of VUCM means a stronger joints synergy and indicates a variety of patterns to control joints. Aging involves modifications of the locomotor system such as neuromuscular adaptation to perform a gait safely and/or efficiently, and some research has examined that the modifications from the point of view of kinematic and kinetic aspects. However, there is little insight into the influences of aging on the utilization of motor redundancy during gait.
Background: Accurate body segment inertial parameters (BSPs) are essential for the motion analysis, but previous studies have never reported about BSPs of pregnant Japanese women. It may be inappropriate to apply BSPs different from that of pregnant Japanese women without consideration for physical constitution.
Background: Low back pain (LBP) is personal but one of socioeconomic issues. The number of patients with LBP has been increasing in advanced countries. The posterior ligamentous system (PLS) has important function for lumbar stability. Recent studies have shown that lowering tasks cause larger lower back loads. In addition, functional disorders of the PLS are risk factors for LBP. Therefore, investigation of the effects of PLS stretched relatively long time in individuals who are in charge of daily lowering tasks is important to identify strategy for prevention of LBP. As far as we had read extensively, there is no investigation have examined the relationship between lowering tasks and the PLS extension, which is important for the prevention of LBP in people who are engaged in daily repetitive lowering tasks.
Background: The human gait has innumerable patterns, and it is performed by coordinating the degrees of freedom of each joint. An increased external knee adduction moment (KAM) during gait is a risk factor leading to medial knee osteoarthritis. Some gait modifications have been shown to reduce the KAM. In particular, increased lateral trunk lean toward the symptomatic knee during the stance phase provides the greatest reduction in the KAM peak. However, how increased lateral trunk lean during gait affects the coordination of body joints is remained unclear.
Background: Falls do not only cause the elderly of functional impairment and loss of self-efficacy but also the burden of a large medical expense. Therefore, preventive strategy of falls in the elderly is one of our primary roles in the 21st century. Adequate sleep and exercise are believed to be essential for elderly to maintain good health and prevent falls.
Background: The human body accomplishes tasks using redundant degrees of freedom, which coordinate each body segment. Fundamental activities of daily living include sit-to-stand (STS), a dynamic motion that requires extensive joint movement in the lower extremities and trunk. STS consists of two components: (1)transition the center of mass (COM) from a wide base of support (BOS) provided by the buttocks, thighs, and feet to a narrow BOS provided by feet alone, and (2)lifting COM from the height in the sitting position to that of standing.
