Human Locomotion 1 Flashcards
define locomotion
the act of moving, or the capability to move from place to place
what examples of human locomotion did we talk about in class?
- walking
- moon walking
- skipping
- crawling
- creeping
- rolling
- cartwheeling
- gallop
- shuffle
- hoping
- walking on hands
- bum scootch
- crab walk
- bear crawl
across the lifespan we will use a variety of methods of locomotion. The type we use will depend on_
interacting constraints
- during childhood, height and weight are changing dramatically, acting as rate limiters
- motivation can encourage or discourage behaviours (eg. skipping is for girls)
- old age can bring structural constraints that act as rate limiters
- fear of falling can be a functional constraint in balance sports
- snow and ice conditions are environmental constraints for runners
in the first voluntary locomotion, what is the first step we see?
crawling with the chest and stomach on the floor
in the first voluntary locomotion, what is the second step we see?
low creeping with the stomach off the floor but the legs working together (symmetrically)
in the first voluntary locomotion, what is the third step we see?
rocking back and forth in the high creep position
in the first voluntary locomotion, what is the 4th step we see?
creeping with the legs and arms working alternately
describe learning to crawl
- no strict progression
- multiple crawling positions often observed
- many infants crawl on their bellies before hands and knees, many skip belly crawling and proceed directly to hands and knees
- amount of experience in early forms of crawling predict the speed and efficiency of later forms
- smaller, slimmer, more well-proportioned infants crawl earlier than do larger, chubbier infants
amount of experience in early forms of crawling predict the
speed and efficiency of later forms
describe crawling on stomach
- prone progression
- belly on the supporting surface
- arms and legs move in reciprical pattern
describe creeping
- prone progression
- belly lifted off the supporting surface
- arms and legs move reciprocally
compare crawling and low creeping
crawling: chest and stomach on floor\
low creeping: stomach off floor but arms and legs working together symmetrically
define quadripedal (locomotion)
walking on hands and feet
after standing is accomplished comes _
supported cruising
describe supported cruising
- first bipedal locomotion
- hands supporting on furniture (awareness of affordance?)
- generally sideways, both arms and legs provide support
approximately 1 month before the onset of unsupported walking, infant can _
stand alone
describethe sensory constraints at the “stand alone’ phase
- vestibular
- visual
- proprioceptive (information provided by the muscles, tendons, joints and skin)
around 11 months, infants can_
take first steps alone
describe the “take first step alone” phase at 11 months
note:
- high guard arm position
- wide base of support
children achieve independent walking generally between
10-15 months
muscle mass at 6 months may predict the onset of _
independent walking
- larger muscle mass may delay acquisition
- also,infants who are smaller boned or have linear frames may acquire this milestone earlier
what are the characteristics of early walking - a beginner walker
note the short stride and high-guard arm position
how do newton’s laws apply to the high arm guard position?
moment of inertia (a body’s tendency to resist angular acceleration)
name the first characteristic of early walking
1) balance easily lost, frequent falls. Compensate, large base of support, short steps
2) little, if any trunk rotation
3) contact with ground is flat-footed. One knee locked, other bent
4) each step independent of other
5) out-toeing. Minimal ankle movement, slight pelvic tilt
6) high-guard position. Limbs fixed, do not swing
*beginner walkers don’t swing their arms in time with their legs
- relfects lack of coordination (inefficient)
at approximately 1 year, what kind of locomotion do we see?
has locomotion on two legs and maintain balance during squat positions
*important step!
- first time doing two (reasonably complex) things at once
- allows for extended environmental exploration
(squat and reach,12m)
summary of early locomotion
- short strides
- very slow
- wide stance
- high guard arms
- on toes
- variable interlimb coordination
define walking
defined by a locomotor phasing relationships between the legs, as well as a period of double support (when both feet are on the ground), followed by a period of single support
define interlimb coordination
timing between the legs/feet at this point of footfalls (steps quickly with other foot… then slower in stepping with the other)
define stand/stance and swing (interlimb coordination)
stand/stance: time when the foot is on the ground
swing: time that the foot is in the air
what did Clark et al. 1988 study?
(early locomotion) variability in gait as defined by “temporal phasing”
high values= instability
*looking to see how many months the person has been walking for
*as we get older, get increasing proficiency (variability of temporal phasing decreased with walking age)
temporal phasing relationship
proficiency in walking means
greater efficiency
characteristics of proficient walkers
- proficient walkers tend to give up some stability for additional mobility and speed
- increase in stride length
- flat-footed changes to heel-to-toe (plantigrade gait)
- reduction of base of support
- pelvis begins to rotate
- oppositional arm swing, as well as arm-leg movements
- mature walking pattern at ~4-5 years
walking becomes more efficient as: (5 things)
1) stride width decreases
2) flat-footed steps dissapear (foot contact)
3) eversion of the foot decreases (foot angle)
4) pelvic rotation increases
5) high-guard position decreases
describe stride width decreasing
- base of support is decreased to within the approximate lateral dimension of the trunk, which increases mobility by allowing for greater stride length
describe the “flat footed steps dissapear” step
- eventually replaced by plantigrade gaiit
- heel-to-toe pattern
- heel strike in front of body with toes in the air, followed by toe contact, with the heel lifting during the maintained toe contact
- each leg spends 60% of time in stance, 40% in swing phase
describe eversion of the foot decreasing
- feet evenly point straight ahead
describe pelvid rotating increasing
- allows full leg motion and oppositional movement of the upper body
describe “high-guard position decreases”
- eventually replaced by a reciprocal arm swing
how does locomotion differ in new walker vs proficient walker?
new walker: fixed arm position important for reducing degrees of freedom
proficient walker: arm swing counterbalances trunk rotation around the vertical axis, degrees of freedom are released (less things they need to focus on)
whats the definition of degrees of freedom (not on slides)
all the factors affecting the range of statesin which a system can exist
describe locomotion in new walkers
- note wide base of support
- asymmetrical steps
- still needs support (no arm involvement)
- high degree of variability of gait/leg movements
onset of walking usually defined as
3-5 continuous steps
in new walkers (later on), describe locomotion
- still a wide base of support
- “high guard” position
- gait inconsistent
- getting some pretty good speed though
describe locomotion in proficient walkers
- high guard gone
- reciprocal arm swing now counterbalances trunk rotation around the vertical axis (degrees of freedom are released)
- arms also available for other things (eg. ball carry)
- heel-toe stride
