KIN 3620 Motor Behavior

Practical reasons for learning about motor development

recognize deviance from typical pattern

Infants' movements that occur without any apparent stimulation

spontaneous movements

Child spontaneously thrusting their legs while laying on their back

supine kicking

In supine kicking, the ankle, knee, and hip joints move _____________, not independent

cooperatively

Difference between supine walking in infants and adults

Infants activate both the flexor and extensor (co-contraction), whereas adults alternate flexor and extensor muscles

Involuntary, stereotypical movement response to a specific stimulus—automatic/unconscious

infantile reflexes

Rooting Reflex

helps newborns find food and helps with breastfeeding

Palmar Grasp Reflex

a way to prepare hand muscles for babies to grasp in adulthood

Moro Reflex

spread arms out when balance is taken away—survival instinct

Asymmetric Tonic Neck Reflex (ATNR)

helps with birthing process, enables infant to see its own hand and facilitates hand eye coordination

3 types of infantile reflexes

1. Primitive reflexes

2. Postural reactions

3. Locomotion reflexes

Involuntary response to specific stimulation that is often mediated by lower brain centers—disappears around ___________

Primitive reflexes, 4th month

help infant automatically maintain posture

Postural reactions

Involuntary modifications of movements produced by sensory signals from receptors in limbs and body (e.g., stepping, swimming, crawling)

Locomotion reflexes

Infantile reflexes _________ after some time

disappear

The purpose of reflexes:

1. Structural - hardwired into brain

2. Functional - helps with birthing process (correct position) and survival (eat, breath, grasp)

3. Applied - helps with voluntary movement development

Fundamental motor skill, the attainment of which is associated with the acquisition of later voluntary movements

Motor milestone

First-time mothers hold their infants for long periods and avoid putting the infants on their stomachs for a long time = can delay motor development

First child syndrome

Early in development, infants with Down syndrome often experience _____ tone

hypotonia

Any condition that delays or impedes infant mobilities may negatively affect ________ development

cognitive

The act of moving from place to place

locomotion

Moving on hands and knees

creeping

moving on hands and stomach

crawling

The first types of locomotion that infants exhibit are usually ________ and _________

creeping, crawling

50% phasing relationship 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

walking

Characteristics of Early Walking

1. short stride, feet wide (balance)

2. Arms up in high guard (not swinging) at first, then later will drop lower with improved balance

Infants have the ability to move their legs in an alternating pattern from birth onward, yet they cannot walk for at least _________ after birth

7 months

Rate limiters in early walking

muscular strength and balance

Characteristics of proficient walking

1. increased stride length

2. heel strike

3. narrower lateral base of support

4. double knee lock

5. pelvic rotation

6. less trunk inclination

7. good arm swing

By age _____, the proficient walking patterns are developed

4

Changes in walking during older adulthood is mostly due to _____________________ (e.g., diet, injury, exercise)

individual factors

Characteristics of walking in older adulthood

1. shorter step length

2. more toed out

3. less ankle extension

4. less pelvic rotation

5. slower walking speed

Rate limiters in walking during adulthood may be caused by both structural and functional constraints, such as _____________________

disease, pain, and fear of falling

A decrease in walking (and other physical activities) leads to a decrease in ____________________

muscle mass and flexibility

50% phasing relationship between the legs and has a period of ______, during which neither foot is in contact with the ground

running, flight

Children typically start to run about ________ after they begin to walk

6-7 months

Characteristics of early running

1. Limited range of motion in legs (less extension/flexion), thus short stride

2. Brief flight period

3. Arms extend at elbows and swing side to side (rather than backward), thus not useful in moving body forward

Rate limiters in early running

strength and balance

To propel themselves into the air, toddlers must have sufficient _______ in each leg to lift themselves off the ground

strength

Once in the air, infants must catch themselves on the other leg and then ______ on that leg while shifting their weight forward

balance

Characteristics of proficient running

1. Increased stride length—greater force applied

2. Greater range of motion—full extension at push-off, heel tucked close to butt, legs swing forward with greater acceleration

3. Lateral leg movements are eliminated

4. Heel-strike pattern

5. Elimination of out-toeing

6. Arms swing forward/backward but elbows at right angles

Rate limiters in later running

opportunity and desire to run

Jumping occurs when individuals propel themselves off the ground with one or both feet and then land on ___________

both feet

Jumping achievements (vertical, horizontal, distance) occur with ____

age

Although children can perform various jumps at younger ages, the _____ in which they acquire those skills is the same

order

Characteristics of early jumping

1. slight crouch before jumping

2. legs not fully extended at liftoff

3. legs are tucked during jump (rather than extended)

4. favor one leg to jump rather than using both legs (symmetrical takeoff/landing)

5. arms not used to assist jumping, instead, either at side or high guard

To improve jumping:

1. Make a symmetrical two-foot takeoff, flight, and landing

2. Fully extend the ankles, knees, and hips at takeoff after a deep preparatory crouch

3. Practice, and continuous growth in body size and strength

By age ___, children can change their trunk angle at takeoff to make either a vertical or horizontal jump

3

To execute proficient jumps, performers do the following:

1. get into a preparatory crouch that allows the legs to apply maximal force as they fully extend at the moment of liftoff

2. heels coming off the ground and with both feet leaving the ground at the same time

3. extend the arms backwards, then initiate takeoff with a vigorous arm swing forward to position overhead

In jumping for height, proficient jumpers do the following:

1. direct force downward and extend the body throughout flight. The gain height through a lateral tilt of the shoulders

2. keep the trunk relatively upright throughout the jump

3. flex the ankles, knees, and hips on touchdown to allow the force of landing to be absorbed

In jumping for distance, proficient jumpers do the following:

1. direct force down and back by beginning the takeoff with the heels leaving the ground before the knees extend. The trunk appears to tip forward

2. flex the knees during flight, then bring the thighs forward to a position parallel with the ground

3. swing the lower legs forward in reaction to the thigh flexing, putting the body in a jackknife position

4. flex the ankles and knees when the heels touch the ground to absorb the momentum of the body over distance as the body continues to move forward

Rate limiters in jumping

muscular strength, stability, force

Hopping occurs when individuals propel themselves with one foot and then land on the _______________

same foot

Characteristics of early hopping

1. arm held to side with slight movement

2. inactive swing leg

3. support leg is pulled off the floor to produce only momentary flight.

Characteristics of proficient hopping

1. swing leg leads the hips

2. support leg fully extends

3. arms move in opposition to legs

4. support leg flexes at landing to absorb the force and to prepare for extension at next takeoff

Hopping continues to develop well past the age of ___

5

Rate limiters in hopping

balance and force

Occurs when individuals propel themselves with one foot and then land on the other foot

galloping and sliding

individual moves forward

galloping

individual moves sideways

sliding

a step and a hop on the same foot, with alternating feet

skipping

Characteristics of early skill patterns

arrhythmic and stiff

Characteristics of proficient skill patterns

rhythmical and relaxed

Proficient skill patterns

1. arms no longer needed for balance

2. in skipping, arms swing rhythmically in opposition to the legs for momentum

3. child can use arms for other purpose during galloping and sliding such as clapping

4. forefoot or heel-to-forefoot landings prevail

5. the knees "give" on landing, remaining flexed while the support the body's weight and extend at takeoff

The first of the three bipedal patterns to emerge

galloping

The last of the locomotor patterns to emerge, usually between 4 and 7 years of age

skipping

Skills in which a person applies force to an object in order to project it

ballistic skills

Examples of ballistic skills

raking leaves, opening a door

The most studied ballistic skill

overhand throw for distance

The type of throw that a person uses, especially among children, often depends on ______ constraints, particularly rules and the size of the ball

task

The most common type of throw

one hand overarm throw

right arm, right leg step

homocentric

right arm, left leg step

contralateral

In early stages of overarm throwing, those less than 3 years of age, overarm throw is mostly done by _______________ (i.e., extension)

arm only

Characteristics of proficient overarm throwing

1.Backswing

2.Forward step (contralateral leg) pelvic rotation

3.Upper spine rotation and upper arm swing

4.Upper arm inward rotation and elbow extension

1.To create force/power

5.Release

6.Follow-through

Developmental changes in trunk in overarm throwing

Step 1: no trunk action

Step 2: block rotation

Step 3: differentiated trunk rotation

________ rotation of the trunk is forward rotation of the lower and upper trunk as a unit

Block

In _________________ trunk rotation, the lower trunk (hip section) rotates before the upper trunk (shoulder section), still preparing to rotate forward

differentiated

Developmental changes in backswing in overarm throwing

Step 1: arm does not move backward before moving forward

Step 2: arm moves backward so ball is behind head

Step 3: circular upward backswing

Step 4: circular downward backswing

Developmental changes in forearm in overarm throwing

Step 1: elbow higher or lower than shoulder as arm swings forward

Step 2: elbow is at shoulder level

Step 3: at time of front facing (trunk is facing forward), forearm lags behind which helps increase speed of throwing

Developmental changes in feet in overarm throwing

Step 1: no step forward

Step 2: step forward with leg on same side as throwing arm

Step 3: step forward with opposite leg, short step

Step 4: step forward with opposite leg, long step

Throwing in Adulthood (60+ years of age)

1. Feet: shorter contralateral step

2. Trunk: block rotation

3. Backswing: begins with circular downward motion but circle is not "completed"

Throwing movements of older adults are characterized more by ________ in the developmental steps than by rapid decline. Change is more often typified by increased variability from throw to throw, a slight slowing of movement, or a more limited range of movement

stability

Ballistic strike from the foot

kicking

Characteristics of a beginner kicker

pushes the leg forward

Characteristics of a moderate kicker

1. steps forward

2. puts leg in cocked position, but leg swing is minimal

3. knee is bent at contact, and some of the momentum of the kick is lost

Characteristics of a proficient kicker

1. wind up (running to ball), stance of body is leaned back

2. flexion before kick, extension after kick—thigh rotates forward and knee extends before contacting ball

3. trunk rotation

4. arm opposition

Form of striking where the arm remains at or below shoulder level

sidearm striking

Example of sidearm striking

swinging a baseball bat

Striking involves the most __________________________________

difficult perceptual judgement

Teachers often adapt striking tasks for young children by making the ball ___________

stationary

Characteristics of early sidearm striking

1. arm action only

2. faces the ball

3. swings down rather than sideways

Characteristics of proficient sidearm striking

1.Stepping into the hit (Step should cover a distance more than half the individual's standing height)

2.Differentiated trunk rotation to permit a larger swing/force

3.Swinging through a full range of motion

4.Extending arms just before contact

5.Linking movements together to produce the greatest force possible

Proficient sidearm striking step should cover a distance _____________ the individual's standing height

more than half

_____________ trunk rotation is used during proficient sidearm striking to permit a larger swing and produce more force

differentiated

Developmental changes in sidearm striking

1. stands sideways (weight on rear foot, step forward, transfers weight forward at contact)

2. use of trunk rotation (differentiated rotation, hip then shoulder)

power grip is also known as

shake-hands grip

Development changes in racket action in sidearm striking

1. chop—swung in vertical plane

2. arm swing only—racket swings ahead of trunk

3. racket lag—racket lags behind trunk rotation but goes ahead of trunk at front-facing

4. delayed racket lag—racket lags behind trunk even at front-facing

Overarm striking is a form of striking where the arm travels _________ the shoulder level

above

Example of overarm striking

swinging a racket in a tennis serve