Time profile of kinematic synergies of stroke gait.

Background: In stroke subjects, the motor skills differ between sides and among subjects with different levels of motor recovery, impacting inter-joint coordination. How these factors can affect the kinematic synergies over time during gait has not been investigated yet. This work aimed to determine the time profile of kinematic synergies of stroke patients throughout the single support phase of gait.

Does thenumber of stepsneededfor UCM gait analysisdiffers between healthy and stroke?

The basis for the uncontrolled manifold (UCM) approach is the variability among repetitions of a motor task. Thus, reliable results might be influenced by the number of trials. This study estimated the number of steps needed for UCM analysis of stroke gait and if it is the same for healthy subjects.

Compensatory control between the legs in automatic postural responses to stance perturbations under single-leg fatigue.

In response to sudden perturbations of stance stability, muscles of both legs are activated for balance recovery. In conditions that one of the legs has a reduced capacity to respond, the opposite leg is predicted to compensate by responding more powerfully to restore stable upright stance. In this investigation, we aimed to evaluate between-leg compensatory control in automatic postural responses to sudden perturbations in a situation in which plantar flexor muscles of a single leg were fatigued.

Instantaneous interjoint rescaling and adaptation to balance perturbation under muscular fatigue.

Adaptation of automatic postural responses (APR) to balance perturbations might be thought to be impaired by muscle fatigue, given the associated proprioceptive and effector deficits. In this investigation, we aimed to evaluate the effect of muscular fatigue on APR adaptation over repetitive balance perturbations through support base backward translations. APR adaptation was evaluated in three epochs: (a) pre-fatigue; (b) post-fatigue, immediately following fatigue of the plantiflexor muscles through isometric contractions and (c) post-recovery, 30 min after the end of fatiguing activity.

Fatigue in complete spinal cord injury and implications on total delay.

The use of neuromuscular electrical stimulation (NMES) to artificially restore movement in people with complete spinal cord injury (SCI) induces an accelerated process of muscle fatigue. Fatigue increases the time between the beginning of NMES and the onset of muscle force (Delay ). Understanding how much muscle fatigue affects the Delay in people with SCI could help in the design of closed-loop neuroprostheses that compensate for this delay, thus making the control system more stable.