Post date: Apr 17, 2016 3:46:08 PM
Developmental Essentials by IYCA
Chapter 2 - Motor Development:
Play is a necessity
Develop mature movement patterns through recess/play so that when students engage in organized physical activity, they are able to perform the basics.
Movement has a deeply conserved evolutionary purpose.
Hunt and escape predators
running
jumping
changing direction
climbing
throwing
Development.
Infant reflexes serve the purpose of:
Growth and development of nervous system
critical period
sensitive period
Development of balance and strength
Proprioception
Squat. Know how to teach
4yr old
8yr old
14yr old
Motor Skills. Skills required for proper usage of skeletal muscles:
Developed spontaneously through environmental exploration, guided discovery.
Skill development benefits from proper training: Provide the correct environment to develop appropriate adaptations based on individual characteristics (current level of development.)
Relevant skills continue to develop into adolescence:
balance
agility
coordination
Effects of living in developed world:
Impetus to explore natural environment is dampened by pursuits of luxury and convenience.
Athletes are entering into organized sports with immature movement patterns which leads to very little early success and decreases motivation to participate. This leaves sports accessible to only those who’ve had the opportunities to develop, the talented and privileged.
Many youth coaches and trainers erroneously treat children as mini professionals
Focus on sport skill or fitness before basic movement development leads to compensatory movement patterns - adding fitness/skill to dysfunction has led to rise in overuse injuries in young athletes.
A wide range of maladaptations can occur. The majority of population demonstrates microscopic damage due to dysfunctional movement patterns, even if they present as asymptomatic
In other words: add fitness to dysfunction and it is not a question of if you will get hurt but when. Remember the first rule of teaching/coaching/training: do no harm. Prevent injury to improve performance.
The false belief that more seat time will improve test scores has led to less time/resources devoted to physical education and free play. Less recess time leaves less time to practice critical movement patterns.
The reality is that more recess time:
Eliminates behavior problems by balancing hormone levels, providing a physical & emotional outlet and provides opportunities for social & emotional development.
Leads to better academic scores by increasing brain activity and providing oxygen to the primitive portions of our brain. Our brains initially developed for the purpose of movement and survival.
Difference between training and development.
Training influences the development of movement skills.
Training can assist development when it provides sufficient opportunities for practice, is fun and is appropriate for developmental level.
Training can be detrimental to the developmental process when student is lacking in fundamental movements (adding skill to dysfunction) or training is too advanced for developmental level which increases levels of frustration and ultimately lack of desire to continue or training that is based on results/achievement rather than being focused on the developmental process.
Development occurs in three stages
Environmental Exploration
Development of locomotion
Development of more complicated and sophisticated athletic/technical skills
Perception and Motor Development.
Receive and process sensory input:
visual
auditory
tactile
kinesthetic
Relationship
Sensory input. Collecting information from the senses.
Sensory integration. The brain organizes information based on prior experiences.
Motor interpretation. A decision made based on sensory integration.
Movement Activation. A movet made.
Feedback
Collect more information.
Further reinforce movement pattern.
Repeat.
Machinery behind motor control
Central nervous system
Frontal lobe - executive boardroom. Forming the plan - motor interpretation, decides when to execute. Includes:
cortex (association areas)
basal ganglia
Brain Stem/Spinal Cord - on site supervisors. Regulation of moment to moment execution of movement. Execution of the program - movement activation.
Performers
workers & secretaries
muscles
sensory receptors in the muscles, tendons and joints - feedback
visual, auditory receptors (sensory integration)
Middle Management
fine tuning/revision
cerebellum
motor cortex
decides which type of workers to best execute plan
In order for the plan to be executed well--information being processed must be accurate
Mimicry - kids need to be shown movements done well.
Be able to demonstrate an accurate example of how the movement pattern is performed.
Influence and encourage children to pursue correct form.
Kids need to be given opportunities to practice and correct the pattern. The consequences of no practice are the development of horribly dysfunctional movement patterns.
Early Motor Development
Newborn. Random, spontaneous movement
squirming, thrusting legs or arms, stretching fingers and toes
these coordinated movements precede voluntary movements performed later
rhythmic in nature
Infantile reflexes are primitive. Occur in response to specific stimulus. Movement is specific and localised. Respond in same manner to same stimuli repeatedly.
postural
respond to gravity
maintain posture in a variety of positions
locomotor
movement in place
swimming
crawling
stepping
deviation may indicate a developmental problem
reflex exhibits when it should not
reflex doesn’t exhibit when it should
examples p. 49
reflex appearance/disappearance is highly influenced by environmental factors--deviation may be caused by developmental delay
Motor Milestones
head rolling - 2 months
rolls to spine - 4 mo.
maintain sitting - 6-7 mo.
rolls to prone position - 7 mo.
crawls on all fours - 10 mo.
stands momentarily - 10 mo.
cruises (few steps, no support) -10 mo.
walks independently - 12-14 mo.
begins to run - 2 yrs.
walks up and down stairs - 2yrs.
runs well - 3 yrs.
walks up stairs alternating leg - 3 yrs.
walks down stairs alternating leg - 4 yrs.
hops on one foot - 4 yrs.
skips - 5 yrs.
mature adult gait - 7 yrs.
Early development of Human Locomotion
Locomotion is the act of moving from place to place
Bipedal locomotion
walking
running
skipping
hopping
marching
jumping
creeping and crawling provides the base
first voluntary locomotion
Walking
early walking
demonstrate
wide base/flat footed support
bowing of legs
lumbar lordosis
gait cycle - foot strike of one foot and subsequent foot strike of same foot
stance phase (60%)
heel strike
toe off
mid stance
swing phase (40%)
leg swings forward
decelerates for foot strike
swing phase is shorter during development due to lack of motor control and balance
characteristics
hands held in high guard
less time spent in single leg support
180 steps/minute
slower speed and rep length
by 12 months 95% of children can squat on the floor without support
development of the squat is present from the beginning of walking
development of mature gait in childhood
by age 2
reduced anterior tilt (lordosis)
less abduction of hips
less external rotation of hips
90% can walk on toes
80% utilize reciprocal arm swing
34% of time is spent on single leg
age 3
90% use reciprocal arm swing
base of support is relatively similar to adults
can still maintain slight increases in:
knee flexion
pelvic rotation
hip joint rotation
hip abduction
pattern of joint angles same as an adult
age 7
cadence has decreased
step length increased
velocity increased
duration of single leg stance is at 38%
assessment of gait
child’s history
age
past and present medical history
age that motor skills are achieved
family history
trouble walking in parents or siblings
anyone in immediate family treated for leg/walking problems
did anyone wear:
leg brace
orthotics
corrective footwear
or have surgery as a child
observation of child’s gait
heel strike
reciprocal arm swing
can squat to play
excessive knee flexion during stances
walk is symmetrical
right/left sides move equally
rate of falling
is it decreasing
common concerns in walking
toe walking
caused by cerebral palsy
idiopathic (no known cause) - resolves itself by childhood
flat feet
arch/instep comes in contact with ground
persistent flat feet after the age of 6 will not improve
knock knees
usually resolves around 7 or 8
some carry into adulthood
in-toed gait
caused by anatomical variation at :
hips
legs
feet
Elements of motor control
nervous system processing
think: learning computer
proprioception
kinesthetic awareness
visual acuity in relation to movement function
perceptual motor development
biomechanical constraints
stature and body proportions and motor development
how their elements influence balance and movement skill
Proprioception and kinesthetic awareness
sense of where limbs are in space
regulation of the amount of velocity and force applied to a movement
Systems involved in joints, muscles, and tendons
joint receptors
joint position
muscle spindles
rate of change of muscle tension
golgi tendon organs
amount of muscle tension
sensors/receptors that provide information about muscle force, tension and direction
Vestibular (orientation) visual systems function in proprioception depending on task employed
Parts of brain
Cerebellum
balance
motor program
basal ganglia
movement planning
initiation/termination
spinal cord
sensory feedback
execution of movement plan
simple reflexes
parts of frontal lobe
final processing of sensory feedback
executive function over all movement
planning
parts of nervous system involved in proprioception continue to develop throughout adolescence
Development of visuomotor ability
ability of central nervous system to integrate visual information into the planning and execution of movements
age 6-11
develop ability to use bidirectional representation of outside world
integration of proprioceptive and visual information increases around 8 years old
trainable with continuous visual feedback
video
mirror
patience is important
avoid undue complexities
keep it as simple as possible but not any less
no substitute for experience
with age/experience comes complexity
before age of 8 - trouble with high arcing balls
throw balls straight or with high arc to improve success rate
Putting it together
proprioception, kinesthetic awareness, visuomotor ability, strength and flexibility come together to achieve/maintain balance--essential to all athletic activities
sensitive period: movement/skills introduced at a time in development when individual can best take advantage of it
repeated resistance = not ready for skill being introduced
spontaneous choice to repeat and activity should be fostered. Our job is to assist what is already developing
static balance
maintaining center of gravity in a stable position
dynamic balance
maintaining stability and body control when the center of gravity is shifting
factors that influence ability to balance
biomechanical constraints
proportionality
musculotendinous strength
peripheral and central nervous system
cognitive abilities of the individual
anthropometric consideration
size
body composition
Skills
static balance
closed loop - ascending integrated sensory info
visual
vestibular
proprioceptive
info sent from limbs and trunk to the CNS
adjustments are constantly made based on info.
dynamic balance
opened loop - predetermined motor program is elicited in response to an internal decision
corrective movements are largely ballistic in nature
actions must be executed quickly
improve from childhood through adolescence
CNS Role
determine which joints/muscles need to be released to rotate and which need to stay tied together to maintain balance
both age and task difficulty influence the level of control
4-6 yr old
unable to reach out far in relation to body
high variability in movement patterns
trial and error is default mode for environmental exploration
10-11 yr old
perform similar to adults on simple tasks
perform like 4-6 yr old on more difficult tasks
seek to make tasks progressively more challenging in order to determine true level of development
Phases in developmental course of posture
kinetic organization
infancy = descending (feed forward) strategy
cephalocaudal gradient
postural control developed proximally first in the neck muscles, followed by the trunk then distally to arms and legs
articulated operation
head stabilization is performed early in development in real time by activating neck muscles first, followed by axial muscles and limbs
early childhood
achievement of upright stance
body begins to operate ‘en bloc’ (in large units)
required for increased control as balance tasks become more dynamic and complex
child may operate as if head is strapped down to the trunk--may move largely as one single unit
may be due in part to size of head in comparison to the body
pelvic stability develops before head and shoulders
sensory input from the feet and contact with the ground and becomes a high priority in information gathering in environment
blocking the joints helps child deal with lack of strength
7 yrs. +
return to strategy of separate articulation of neck and trunk
descending control becomes more important
10-12 yr old may be just entering the stage to look around and run at the same time
Development of static balance
Develops through adolescence
1 leg balance improves from 5-18
4-6 yr old
switch from one leg ballistic to one leg sensory control
use more proprioceptive information
velocity and direction of movement
gained from peripheral nervous system to create meaningful movement strategies
reaches peak around 8 yrs old as improved use of visual vestibular and proprioceptive pathways
coincides with motivation in the connections of motor control centers (basal ganglia and cerebellum and motor cortex with spinal cord
8 yr old
fine tuned control over balance
still have trouble with static balance on more difficult tasks
sensory integration still not complete
still being refined into adolescence
greatly influenced by strength and flexibility
need to develop both equally for optimal balance
Training to improve balance ,
try this
play games where they must balance
forget set/reps package
agility ladders
tag variations
obstacle courses
Development of basic human movements
influencing factors
proprioception/balance, visuomotor coordination, perceptual motor proficiency
physical development maturation, heredity, environmental factors (extrinsic) - stimulation deprivations
gender
basic human movements
many of the basic human are never developed or are lost due to luxury no longer spend time:
squatting in the sand box
play wrestling
pulling and pushing items around the yard
squatting and lunging - squat is the basis of many human movements
erect posture (pvc pipe)
hips and knees should flex together
hips should move behind shoulders as individua goes down (imagine rope pulling you back and down
shoulders and knees balanced over toes, vertical shins
heels should remain flat (root shoes into the ground
lunge
heel should always be flat on the ground
Cues
younger children - drop your hips back and down
rope pulling your waist back and down
adolescents - allow the muscles in the back of your legs to stretch out as you drop your hips
stretch the rubber band
all kids - grow your trunk tall the whole time
pole running through the top of your head and out your bottom
all kids - root your shoes and drive through your heels
push the ground down
Demonstrate correct movement first
thier patience for the movement will be as high as our patience is
pushing
does not wear shoulders as earrings
shoulder blades in the back pocket
elbows @45 degrees - ½ way up
strong erect but relaxed posture
creates torque
squeeze orange/rip floor apart
teaching
progressions from an incline
cues
keep whole body long and relaxed
shoulders relaxed out of neck
use your chest muscles and reach your chest to the ground
pulling
child does not wear the shoulders as earrings
elbows behind or under the hand
strong erect but relaxed posture
teaching
pull shoulder blades together while you straighten up
in your back pocket
create a shelf for pulling
relax your shoulders while you pull down
make a ‘w’ (pulling down)
pull with big muscles in your back
Grow spine tall but keep ribs cement to pelvis
running
no double support phase, replaced with flight phase
may adopt 6 to 9 months after beginning to walk
wide footed base
flat footed landings
knee extension at mid support
high arm guard position
arms swing out to side
with experience they will take on a more natural pattern
ground contact
force
increase in flight phase/stride length=increase in speed
thigh parallel to the ground heel under glute
increased range of motion in the knee
land on midfoot
joints stacked--centration
improved strength. balance and coordination
elimination of lateral leg movement (out toeing)
arms swing forward and backward in opposition to legs - elbows remain at roughly 90 degrees
Drill: Falling starts
face each other, push by driving arms and legs
let them go
execute on fall
Jumping
initial stage -spontaneous development
inconsistent preparation and positioning
poor integrated body extension
head tends to stay down
inability to use peripheral visual cues
lack of coordination with arms
difficulty exploding off of ground due to lack of strength and extension
age 3 - able to change angle to initiate either a vertical or horizontal jump
tendency to keep trunk too erect during horizontal jump
Intermediate stage
knee flexion goes past 90 degrees
exaggerated forward lean on jump
able to produce power but not able to change angle to initiate either a horizontal or vertical jump
tendency to keep trunk too erect during horizontal jump
efficiently
no full extension
arms attempt to assist but not efficiently
excess horizontal displacement during preparation due to
excess body lean
lack of extension
mature jumping
observed at approximately 9 to 10 yrs old
pattern depends on:
strength to bodyweight ratio
active range of motion
developmental stage
experience/exposure to athletic activity--may show immature movement pattern into adolescence due to lack of exposure or poor coaching
proficient jumper characteristics
use stretch shortening cycle efficiently
stand in good preparatory crouch (hip hinge)
allows legs to make good use of triple extension
hips behind shoulder, weight towards the front of the foot
extend arms backward, initiate takeoff with forward arm swing
vertical jump
direct force downward, extend body throughout the course of the jump. If reaching or striking, dominant hand swings up and opposite down
tilt shoulders laterally to increase height of jump
trunk mainly upright
hip knee and ankle flexion upon landing (force absorption), joints stacked
upward head tilt, eyes on target (increased ability to incorporate proprioceptive information into movement)
horizontal jump
direct force downward and back to initiate movement
begin take off with heel leaving ground before full knee extension (heels come off the ground together as do feet), trunk leans slightly forward
flex knees during flight phase, thighs forward until parallel to ground
swing lower legs forward to prepare for landing
trunk comes forward
triple flexion upon landing to absorb force
teaching/coaching
jump is built from hinge pattern...develop this first
shift weight to from of foot
body is loose and ready for action
push the ground away very quickly
jumping to reach
target helps with drive and extension
throwing
initial stage
throw from elbows (pushing throw)
fingers spread at release, follow through is down and forward
little to no trunk rotation or leg contribution
intermediate
neutral elbow flexion, hand behind head
arm swing is forward over shoulder. trunk and shoulder rotate toward throwing side
trunk flexes forward and weight shifts forward
mature
6 ½ to 8 years old
influenced greatly by experience and level of instruction
greatly influenced by experience and level of instruction
proficient throw characteristics
arm swings back during preparation, no dominant elbow raised for balance, weight on rear foot
throwing elbow moves forward, as it extends forearm pronates
definitive rotation through hips, legs, spine and shoulders toward throwing side
deliberate step with contralateral leg
influences
instruction
cues
ball size
Distance/velocity is affected by
proficiency of technique (sequencing)
body mass
lever arm (forearm length)
shoulder to hip ratio (torque)
teaching/coaching
cues
take a long step toward your target
take arm straight down then shield it back to form an ‘L’ away from head
watch target, release when you see your fingers
use appropriate ball size and weight
children not encouraged to participate in physical activity will suffer delay in motor control
catching
Initial stages
lack of fine motor control
presence of fear -- avoidance response
arms in front supinated
little use of fingers/hands
traps ball with body
may attempt to catch with hands with little success
proficient catching pattern
no avoidance response, eyes able to track object into hand
arms relaxed at sides (not held out wide) forearms held out in front for preparation
the arms give on contact, hands and fingers grasp object (well timed and simultaneous) “soft hands”
influences
size and weight of object being caught
prior experience
skill of thrower
developmental stage
visual acuity
teaching coaching
toddlers - begin by rolling ball
use ball that is small and soft enough
older beginners - toss ball to self
progress to underhand and then overhand
cues
eyes on the ball
read the words on the ball
cup and grab ball with fingers
step towards the ball
skipping
initial stage
one leg deliberate step hop
double hopping or stepping
no use of ams, action is not smooth(segmented, jerky)
intermediate stage
step and hop become more coordinated
reciprocal use of arms
exaggerated vertical lift on hop, flat foot landing
mature skipping
rhythmical smooth weight transfer
rhythmical arm swing aids in explosion
exaggerated hop more controlled, efficient low vertical lift
lands on ball of foot first--use of stretch shortening cycle to affect ballistic movement
slide/shuffling
initial stages
arrhythmic patterns
feet often cross
flexion of trailing leg during flight phase
foot contact: heel to toe
no significant use of arms (balance/compensation only)
intermediate stage
pattern is choppy and stiff, overly vertical
arms assist in balance
trailing leg may lead in flight but do not cross
increased tempo
mature pattern
smooth action with moderate pace
trailing leg lands adjacent to lead leg
both legs flexed during flight
center of mass stays low, able to stay on balls of feet
arms used to create momentum
teaching/coaching
walk the pattern
make certain toes point forward
partial squat/athletic ready position
kicking
initial stage
all leg
trunk erect
arms to maintain balance
motion more push than strike
intermediate stage
preparatory backswing
kicking leg remains bent
only use to follow through
steps to ball will be choppy and poorly timed
mature kicking pattern
arms swing reciprocally with leg (rotary trunk involvement)
kick is powerful thru the hip
trunk flexed at follow through (support leg bent slightly at contact
follow through is high and support leg will lift (possibly leave ground as a result of a forceful swing
Summary
everybody falls in a different part of the developmental continuum
some parts of a movement pattern may develop prior to others
key is to provide appropriate challenge to encourage further development
fun plays a critical part in further development
no fun = no desire to continue developing
use obstacle courses - everybody loves obstacle courses
alternative training
use elements of different movement practices to improve dynamic flexibility/stability
Special Populations
Help them understand that everyone is born with strengths and weaknesses. Its how we handle and grow from them that matters.
Consult physician/physical therapist in the event of a profound development deficiency.
Developmental coordination dysfunction (clumsy children) - one or more of the following.
developmental dyspraxia - impaired organization of movement
minimal cerebral dysfunction
deficits in sensory integration - inability to use sensory information to plan/solve problems
6% of population exhibits signs (5 to 11yrs old)
work closely with parents to communicate need for specialized attention
child will need more practice, not less as there is a tendency to shy away
build confidence with simple tasks first
emphasis should be on enjoyment of activity -non competitive
may be beneficial if child participates in program design
ADHD
difficulty with sensory integration
proprioception
establishment of limb dominance
Use
layered instruction - step by step - one piece of information at a time
1v1 situation works best (group distracts) when learning new skill
Deaf Children
deficits
balance
overall motor skill
developmental delay in acquisition of skills in proprioception
sensory integration is less efficient due to lack of auditory component
may not develop as fast but can quickly catch up with time and instruction
Take the time to determine between developmental delay (normal) : my job, and developmental disorder (dysfunctional) : refer out.