BACKGROUND Below-knee amputees commonly experience asymmetrical gait patterns and develop comorbidities in their intact and residual legs. Carbon fiber prosthetic feet have been developed to minimize these asymmetries by utilizing elastic energy storage and return to provide body support, forward propulsion and leg swing initiation. However, how prosthetic foot stiffness influences walking char...

malian animals, i.e. that of a cat. It was also influenced by the spring-mass model representation [2]. Compliant prismatic legs show an intrinsic robustness for their angle of attack [2], they have a stability region. If the leg design is changed into a two segmented leg with a specific linear torsional spring, the leg stiffness kleg becomes nonlinear (Fig. 2(b) blue line), similar to that of ...

With respect to cyclic movements such as human gait, running or hopping, leg stiffness is a little variable parameter. The aim of this study was to investigate changes in leg stiffness during the phase of countermovement and take-off when performing a single maximum counter-movement jump. Kistler force plates and a BTS SMART system for comprehensive motion analysis were employed in the study. T...

The development of bipedal walking robots is inspired by human walking. A way of implementing walking could be performed by mimicking human leg dynamics. A fundamental model, representing human leg dynamics during walking and running, is the bipedal spring-mass model which is the basis for this paper. The aim of this study is the identification of leg parameters leading to a compromise between ...

Running-specific prostheses (RSF) are designed to replicate the spring-like nature of biological legs (bioL) during running. However, it is not clear how these devices affect whole leg stiffness characteristics or running dynamics over a range of speeds. We used a simple spring-mass model to examine running mechanics across a range of speeds, in unilateral and bilateral transtibial amputees and...

Spring-mass models have been used to characterize running mechanics and leg stiffness in a variety of conditions, yet it remains unknown how running while carrying a load affects running mechanics and leg stiffness. The purpose of this study was to test the hypothesis that running with a load increases leg stiffness. Twenty-seven subjects ran at a constant speed on a force-measuring treadmill w...

Spring-like leg behavior is found in both humans and animals when running. In a spring-mass model, running proves to be self-stable in terms of external perturbations or variations in leg properties (for example, landing angle). However, biological limbs are not made of springs, rather, they consist of segments where spring-like behavior can be localized at the joint level. Here, we use a two-s...

PURPOSE To determine whether the stiffness characteristics of the leg change during a treadmill run to voluntary exhaustion. METHODS Fifteen runners performed a test run at a constant speed that elicited approximately 80% of their .VO(2peak). The run was performed on a treadmill instrumented to measure vertical ground reaction forces; vertical stiffness and leg stiffness were calculated from ...

Most prosthetic feet are designed to improve amputee gait by storing and releasing elastic energy during stance. However, how prosthetic foot stiffness influences muscle and foot function is unclear. Identifying these relationships would provide quantitative rationale for prosthetic foot prescription that may lead to improved amputee gait. The purpose of this study was to identify the influence...

[Purpose] This study aimed to examine the immediate effects of kinematic taping on the tone and stiffness in the leg muscles of subjects with flexible flat feet. [Subjects and Methods] A total of 30 subjects, 15 in the kinematic taping and 15 in the sham taping group, were administered respective taping interventions. Subsequently, the foot pressure and the tone and stiffness in the tibialis an...