locomotion Flashcards
what type of muscles are involved in the swing and stance movements?
swing - flexors
stance- extensors
what are the ground reaction forces while walking ?
vertical force on heel strike
then deceleration
push off has accelerating force
then secondary vertical force
what is the most beneficial way of running in terms of foot placement ?
running with heel strike will cause hell pain
running of forefoot is most beneficial
- less jolt movement, makes smoother movement
how do muscles control walking ? (3)
beginning stance - eccentric contraction of extensors
- braking action
end of stance - concentric action of extensors
- push off power
during swing- flexors carry leg in air
how does the tibias anterior effect walking ?
foot clearance during swing is controlled by the tib
some disorders can cause paralysis of this muscle making it harder to dorsiflex foot from ground
how do pendulums relate to walking ?
human like hair is achieved with passive mechanisms
NS exploits these properties to create walking action
right leg lifts up so body moves to the right - like pendulum
how did research on animals help study locomotion? (4)
the MLR was electrically stimulated to induce locomotion
increased intensity increased gait speed
MLR doesn’t produce loco pattern
MLR triggers loco and determines speed
what is central pattern generation (CPG)?
the spinal cord can independently generate oscillatory activity, independently of sensory feedback
what is locomotor CPG?
complex neural network capable of producing functional locomotor muscle activation patterns without contribution form afferent feedback
what is CPG has centres ? (3)
there’s 2 groups of excitatory motor neurons - flex+ extend
inhibitory interneurons cause mutual inhibition
so when flexors active, extensors inhibited
what is meant by flexor reflex afferents in terms of CPG half centres ?
stimulation of sensory neurons induce alternating pattern of flexion-extension
what sensory feedback helps modulate CPG?
proprioceptive info from hip flexors initiate swing phase
how does descending tracts influence CPG? (3)
motor cortex - plans movement based on visual signals
MLR - initiates locomotion
cerebellum - adjusts pattern base don sensory feedback
how does running on a track effect speed ?
tighter curve (inside lane) makes you run slower
different forces act on body when running at angle - leads to increase in time oft is spend on the floor which decreases speed
