Time- and frequency-domain analysis of the coupling between pairs of electromyograms (EMG) recorded from leg muscles was investigated during walking in healthy human subjects. For two independent surface EMG signals from the tibialis anterior (TA) muscle, coupling estimated from coherence measurements was observed at frequencies </=50 Hz, with identifiable peaks occurring in two frequency bands...

Robots can help to demonstrate and prove concepts on human locomotion such as concepts based on springlike leg behavior. Hopping is a fundamental requirement for running in two basic functions: bouncing and balancing. In addition, for robust hopping against perturbations, swinging the leg in flight/swing phase is observed. These three elements need to be integrated for stable/robust locomotion ...

Animals modify their behavior constantly to perform adequately in their environment. In terrestrial locomotion many forms of adaptation exist. Two tasks are changes of walking direction and walking speed. We investigated these two changes in motor output in the stick insect Cuniculina impigra to see how they are brought about at the level of leg motor neurons. We used a semi-intact preparation ...

Locomotor patterns are generally very consistent but also contain a high degree of adaptability. Motor adaptation is a short-term type of learning that utilizes this plasticity to alter locomotor behaviors quickly and transiently. In this study, we used a variation of an adaptation paradigm in order to test whether explicit information as well as the removal of the visual error signal after ada...

Persons with quadriceps muscle weakness are often prescribed a knee-ankle-foot orthosis that locks the knee in full extension during both stance and swing phases of gait. Locking the knee results in abnormal gait patterns characterized by hip hiking and leg circumduction during swing. The stance-control knee-ankle-foot orthosis (SCKAFO), a new type of orthosis, has emerged that permits free kne...

We used a simple model of passive dynamic walking, with the addition of active powering on level ground, to study the preferred relationship between speed and step length in humans. We tested several hypothetical metabolic costs, with one component proportional to the mechanical work associated with pushing off with the stance leg at toe-off, and another component associated with several possib...

Human walking must be flexible enough to accommodate many contexts and goals. One form of this flexibility is locomotor adaptation: a practice-dependent alteration to walking occurring in response to some novel perturbing stimulus. Although studies have examined locomotor adaptation and its storage by the CNS in humans, it remains unclear whether altered movements occurring in the leg contralat...

We investigated corrective reactions for backward balance losses during walking. Several biomechanical studies have suggested that backward falling can be predicted from the horizontal position and velocity of the body center of mass (COM) related to the stance foot. Our hypothesis was that corrective reactions for backward balance losses depend on whether the body moves forward or backward aft...

Impaired ankle plantar flexor (APF) function is a frequent cause of gait limitations, but the role of the APF in the forward propulsion of the body remains controversial. To better understand both the direct and indirect effects of the APF during push-off and through advancement of the leg, mechanical work and inverse dynamic analyses were performed on 8 normal subjects during level walking. Du...

background: gait disorder is a common motor complication after stroke. studies have revealed that conventional physiotherapy cannot manage this disorder efficiently; therefore, more studies regarding efficient treatment protocols are crucial. the purpose of this study was to investigate the effect of compelled weight-bearing approach on muscle activation patterns during walking in individuals w...