KIN 410 Motor Control & Motor Learning

KIN 410

Motor Control & Motor Learning

Lecture notes 2018-19

Dr. Gordon Chalmers Dept. of HHD

Western Washington University

Study guides for tests are located at the end of the lecture notes

Ó 2019, Gordon Chalmers, Ph.D.

Motor Learning Community Instruction Assignment

Each student will complete a community instruction field experience involving motor skill instruction.

You must select a work site which is related as closely as possible to your field of career interest. A list of some previous field placement sites is provided. You are not restricted to these sites. Students who get the most out of this project are the ones who search out a site that interests them. The site you choose must allow you to get involved in instructing the participants in some motor skill, to allow you to complete the assignment. Preferably you will instruct the same person (or people) over a period of time, but this is not always possible and in some cases you will find yourself working with different people.

Your work site must be volunteer, and the time spent there must not be time you are using for credit toward any other KPE program course. If you use work at one site for credit in two courses at the same time, you must complete the 8 hour requirement for this assignment, plus the hour requirement for the other assignment. A contract, stating where you will be working and how it relates to your future interests is due on the date listed in the course outline.

Successful completion of this project involves the following:

• a minimum of 8 hours of practical experience

• a typewritten report, double-spaced

You must include a note written and signed by your community volunteer site supervisor stating that you completed at least 8 hours of volunteer work for KIN 410, and the date it was completed. This must be on letterhead or memo stationary from the organization you volunteered with, or with an attached business card of your supervisor.

The grading key used to mark this assignment is distributed with this assignment. This describes the components needed in the report, use it as a guide when planning what to include in the assignment. Use the headings in the grading sheet to organize your report. READ THE GRADING SHEET CAREFULLY, IT DESCRIBES WHAT NEEDS TO BE INCLUDED IN THE VARIOUS SECTIONS OF THE REPORT. The grading key must be attached to your report as the last page of the report. For this report, writing in a first person narrative format is acceptable (e.g., I asked the child to…”). You must protect the confidentiality of your students. This means you do not use their actual names in your report. Either state that you will be using pseudonyms, or refer to them as “A student..” or “Student X…”. Use of a pseudonym or a generic label allows you to refer to the same student across examples.

Written reports are due at the start of class on the due date announced in class. Reports submitted after the deadline will lose 10% of the total possible marks per day.

Hint to successful completion of this assignment: (1) Start right away, setting up your site and putting in the

hours. It is easy for a class to be canceled or your student to be sick. So plan to have the hours completed

Motor Learning Community Instruction Assignment

The skill should not be too simple, or you will not need to use a variety of teaching techniques, and will have little to report on. You must discuss your role and goals with your work site supervisor when setting up the internship, to ensure that you can fulfill the requirements of the assignment. If in doubt, discuss your volunteer work with Dr. Chalmers before you spent time there . The use of public schools is only permitted for this assignment ONLY if you a student ACCEPTED into the PE pedagogy program and you already have your background security check. You must provide documentation to Dr. Chalmers that you have this background check. Students are also not allowed to teach other students a skill. The instruction of weight lifting is not allowed, it is too simple of a motor skill. The only exception to this exclusion of weight lifting instruction is for the instruction of elite competitive weight lifters.

NAME OF PROGRAM AND/OR DESCRIPTION OF ACTIVITY

TIME/PLACE CONTACT PERSON/PHONE/EMAIL/WEBSITE

Whatcom Family YMCA -climbing wall

1256 N. State St., Bellingham

Mary Latta 360-733-8630 [email protected] Whatcom Family YMCA -

youth sports

1256 N. State St., Bellingham

Alex Ramsey 360-733-8630 [email protected] Courtney Lange 360-733-8630 [email protected]

YMCA Girls on the Run Varies Jen Gallant [email protected]

Ferndale YMCA 5610 Barrett

Rd., Ferndale

360-380-4911 Sudden Valley YMCA 8 Barnview Ct.,

Bellingham

360-746-8444 Skagit Valley YMCA 215 East

Fulton, Mt.

Vernon

Jennifer Kerkvliet 360-336-9622 [email protected] Skagit Valley YMCA Girls on

the Run

Roosevelt Smith

[email protected] Lynden YMCA – youth sports 100 Drayton

St., Lynden

Lisa Vanzanten 360-354-5000

Lynden Youth Sports Varies 360-354-0597 [email protected] www.lyndenyouthsports.com

Bellingham Bay Gymnastics 1414 Meador Ave., Suite H- 100,

Bellingham

Jill 360-715-8842 [email protected] www.bellinghambaygymnastics.com

Bellingham Parks &

Recreation

Varies 360-778-7000

Skagit County Parks &

Recreation

Varies Brian Adams 360-336-9414 [email protected] Bellingham Boys & Girls Club Varies

Ferndale Boys & Girls Club Varies Molly Simon 360-384-0753

Motor Learning Community Instruction Assignment

Lynden Boys & Girls Club Varies Audrey Seaholm 360-354-9959 [email protected] Skagit County Boys & Girls

Club

Varies Sarah Levy 360-428-6995 [email protected] Northwest Therapeutic

Riding Center – side walker

1884 Kelly Rd., Bellingham

Julia Bozzo 360-966-2124 [email protected] www.nwtrc.org

Merrill Gardens/Emeritus at Cordata – senior activity facilitator

4415

Columbine Dr., Bellingham

Annie Castle 715-8822

Mt. Baker Care Center – senior activity facilitator

2905 Connelly Ave.,

Bellingham

360-734-4181

The Willows – senior activity facilitator

Fairhaven Estates Assisted Living – senior activity facilitator

2600 Old Fairhaven Pkwy, Bellingham

Janet Newman 360-647-1254

[email protected]

Tai Chi or Yoga instruction Bellingham Vet Center

3800 Byron Ave

#124,

Bellingham, WA 98229

Brent Waggoner, B.S., Office Manager 360-733-9226, [email protected]

Bellingham Parks and Rec.

Adapted Aquatics Program – pool buddy

1114 Potter St., Bellingham

Rhonda Flatz Stouder 360-778-7074 rrflatz- [email protected]

www.cob.org/services/recreation/aquatic/

Note: If you do your community work at the Adapted Aquatics Program you may not complete your 8 hour requirement by the due date of the assignment if you attend one hour per week. In this case, contact Dr. Chalmers well before the due date to get an extension on the due date.

FINALLY: Please help keep this list of community contacts up-to-date. If you contact an agency on this list and the contact person

or phone number has changed, or if they are not interested in volunteers, please let Dr. Chalmers know. If you work with a

person or agency not on this list, and they would be interested in having volunteers in the future, please also let Dr. Chalmers

Motor Learning Community Instruction Assignment

organization, class instructor, or police. If the program participant is in immediate danger, then 911 should be called immediately.

Part B: If you volunteer to do activities with children or vulnerable adults outside of a service organization (e.g. teaching a family friend’s child or relative a motor skill).

Western’s Kinesiology students are expected to be positive role model for children, act in a caring, honest, respectful and responsible manner and should follow the expectations below to avoid behaviors that may be viewed as inappropriate or harmful to children, and potentially harmful to yourself. A child is considered to be any person under 18 years of age.

Note: These guidelines can also be applied to volunteer activities with vulnerable adults.

Interaction

 Do not be alone with a single child. If one-on-one interaction is required, meet in open, well illuminated spaces or rooms with windows observable by other adults, unless the one-on-one interaction is expressly authorized in writing to you by the child’s parent/guardian.

 Do not initiate a meeting or meet with children outside of your planned volunteer activities (e.g. off-site meetings). Any exceptions should be expressly authorized in writing to you by the child’s parent/guardian.

 Do not invite children to your home. Any exceptions should be expressly authorized in writing to you by the child’s parent/guardian.

 Do not engage or communicate with children through email, text messages, social networking websites, internet chat rooms, or other forms of social media at any time except and unless it is expressly authorized in writing to you by the child’s parent/guardian.

 Do not be alone with a single child in a vehicle. When transporting a child related to your volunteer activities, more than one adult should be present in a vehicle or ask the child’s parent/guardian to transport you.

Sexual

 Do not engage in any sexual activity, make sexual comments, tell sexual jokes, or share sexually explicit material (or assist in any way to provide access to such material) with children.

 Do not engage or allow children to engage you in romantic or sexual conversations or acts.

Touching

 Do not touch children in a manner that a reasonable person could interpret as inappropriate.

Touching should generally only be in the open and in response to the child's needs, or for a purpose that is consistent with your planned Kinesiology volunteer activities. Any resistance from a child should be respected.

NOTE. Pats on the back or shoulder are generally considered appropriate, while corporal punishment, patting the buttocks and full hugs are considered inappropriate.

Abusive conduct

 Do not engage in any abusive conduct of any kind toward, or in the presence of, a child, including but not limited to verbal abuse, striking, hitting, punching, poking, spanking, or restraining. If restraint is necessary to protect a child or other children from harm, all incidents must be documented and disclosed to the child's parent or guardian.

 Do not possess or use any type of weapon or destructive or explosive device.

Alcohol or illegal drugs

 Do not use, possess or be under the influence of alcohol, marijuana, controlled substances or illegal drugs while on duty or when responsible for a child’s welfare.

Report suspected abuse or neglect

 If you suspect abuse or neglect of the child you volunteered to work with, visit the DSHS website

(www.dshs.wa.gov) for information about reporting your concerns. In general, child abuse and neglect is injury, sexual abuse, sexual exploitation, negligent treatment or maltreatment of a child by any person under

circumstances which indicate that the child's health, welfare, and safety is harmed.

Part C:

Sexual Harassment: If I am subject to sexual harassment I will report this to my faculty supervisor or chair of the HHD department (see also WWU policy PRO-U1600.02A).

Discrimination: If I am subject to discrimination (including sex discrimination) during this community work I must report the discrimination to my university advisor or chair of the HHD department , as required under WWU policy POL- U1600.04 Preventing and Responding to Sex Discrimination Including Sexual Misconduct.

Acknowledgement of Risk and Hold Harmless: I acknowledge that I am responsible for identifying and assessing risks to

Motor Learning Community Instruction Assignment

unacceptable level of risk, I will immediately discontinue the activity and notify my faculty advisor or field site supervisor. Therefore, any activity of this community work in which I participate will be considered to have been undertaken with my understanding and acceptance of the risks.

If injured: If I am injured at a community work site or activity I must report the injury to my university advisor or chair of

the HHD department within 24 hours of the accident. The university advisor or chair completes the University’s

accident reporting procedures.

Motor Learning Community Instruction Assignment Grading Sheet NAME:_______________________________________

1: .Project site (a) Name of program

(b) Location and contact person

(c) Brief program description (e.g. 1-3 sentences)

2: Report of teaching methods used (2-4 Pages, double spaced)

Each of these topics does not need to be described for each day. You must report and explain ONE specific example for each teaching technique topic listed, using the terminology used in class. Your explanation must demonstrate both knowledge and understanding of the teaching technique (by the use of the correct terminology and context for its use), and the appropriate application of the teaching technique (by the example you give). See the additional specifics described with each section heading listed below. If a specific teaching method was not used, tell why you could not or would not use it with your student(s).

The report must be organized following the sequence listed below, and using the following bold subheadings to identify each section: Stages of learning; Attention; Part instruction; Augmented feedback; Reaction to the experience.

 Stage(s) of learning observed (not skill classification). What stage of learning were the students in, and how could you tell this? /2

 Attention demands and instruction. Identify two enduring dispositions acting on your learner that influenced learning (2 points). The enduring disposition examples may illustrate factors that were naturally in the learner’s environment that helped or hindered learning, and/or factors that you created in the learning environment to facilitate learning. For each of the two examples, state which of the type of enduring disposition (visual, meaningful, or unexpected) the example illustrates (1 point). /3

 Part instruction employed. Give a good example of one part instruction method used. /2

 Augmented feedback provided to learner. Describe the sort of feedback you provided. You must give one example of the KR (1 point), one example of the KP (1 point) you used, and explain why they were appropriate for your student (s) at their stage of learning (1 point). You must identify which example is of KR, and which example is of KP. /3

 Reaction to the experience. What was your reaction to the experience? Did it have any particular impact on you, develop any new understandings, etc.? /0.5

_______ Correct grammar and spelling.

_______ Inclusion of note from supervisor Total /10.5

Motor Learning Introduction & Unit 1: Skill Classification

WHAT IS THE DIFFERENCE BETWEEN "MOTOR LEARNING" AND "MOTOR CONTROL"?

MOTOR LEARNING encompasses, in most cases, behavioral/psychological approaches to examining motor skill learning as reflected by the pattern of change in performance over trials and the relative persistence of that change during a retention or transfer test, i.e., how do you set up the learning environment to optimize learning.

MOTOR CONTROL encompasses, in most cases, physiological approaches to understand how motor skills are controlled by the neuromuscular system.

KIN 410 Unit 1: Skill Classification

Skill Classification

Whole versus part instruction

LEARN PRINCIPLES TO ALLOW US TO OPTIMIZE MOTOR SKILL INSTRUCTION Augmented

feedback

Attention and learning

Stages of Learning

SKILL CLASSIFICATION

1) PRECISION OF MOVEMENT GROSS large muscle groups FINE control of small muscles

All skills exist in a continuum between these two extremes of GROSS & FINE 2)

PREDICTABILITY OF ENVIRONMENT

closed skill = fixed, unchanging environment, , or completely predictable pattern (eg. of latter is escalator)

you decide when & where to do skill

open skill = temporal &/or spatial change in environment

Motor Learning Introduction & Unit 1: Skill Classification

M O V E M E N T O U T C O M E Only one outcome, or

outcome not important

Multiple outcomes required, and outcome

quality important CLOSED SKILL

( p e r s o n c a n i g n o r e , o r p r e d i c t , t h e e n v i r o n m e n t w h e n d o i n g s k i l l )

Category 1 hit ball from T

Category 3

hit ball on T to different heights

OPEN SKILL ( p e r s o n m u s t r e s p o n d t o u n p r e d i c t a b l e e n v i r o n m e n t w h e n d o i n g s k i l l )

Category 2

hit ball from pitcher

Category 4

hit ball from pitcher to different heights

For a category 4 motor skill you teach: Describe it & explain why it is in category 4.

Determine what related skills that would fit in more basic categories that could be used to help

learn the goal skill.

Motor Learning Unit 2: Whole & Part Learning

W H O L E A N D PA RT L EA R N I N G

PA R T P R A C T I C E T E C H N I Q U E S 1 ) P R A C T I C E G R O U P E D PA R T S

C a n p r a c ti c e p a r t s i n d e p e n d e n t l y i f t h e y d o n o t d e p e n d o n o t h e r p a r t s

T E N N I S S E R V E : g r i p , s t a n c e , b a c k s w i n g , t o s s a r e i n d e p e n d e n t , c a n b e p r a c ti c e d s e p a r a t e l y , a n d i n a n y o r d e r

M u s t p r a c ti c e p a r t s t o g e t h e r i f t h e y a r e h i g h l y d e p e n d e n t o n e a c h o t h e r

T E N N I S S E R V E : f o r w a r d s w i n g , b a l l c o n t a c t , f o l l o w t h r o u g h a r e d e p e n d e n t , s h o u l d b e p r a c ti c e d t o g e t h e r

T h e n p u t g r o u p s t o g e t h e r f o r t h e w h o l e s k i l l

2 ) P R O G R E S S I V E PA R T

Te a c h p a r t s o n e a t a ti m e , w i t h e m p h a s i s t h a t y o u l e a r n t h e fi r s t p a r t fi r s t , t h e n a d d t h e n e x t p a r t , t h e n a d d t h e n e x t e t c .

v e r y u s e f u l f o r l e a r n i n g l e n g t h y c o m p l e x r o u ti n e s t h a t i n v o l v e a l o t o f m e m o r y

e . g . , d a n c e r o u ti n e s , m u s i c s c o r e s 3 ) S I M P L I F I C AT I O N

d o a s i m p l i fi e d v e r s i o n o f t h e w h o l e s k i l l .

e . g . , j u g g l i n g s c a r v e s i n s t e a d o f b a l l s t e a c h e s t h e c o n c e p t &

c o o r d i n a ti o n , a t a s l o w e r s p e e d

Motor Learning Unit 3: Stages of Learning

STAGES OF MOTOR SKILL LEARNING Fitts & Posner 3 stage model

1. Cognitive Stage

lots of thinking, while you practice many gross errors

inconsistent performance poor coordination

e.g., limb used as one segment

instructor must give very specific information on what to do = what errors are and how to correct them

2. Associative Stage

basic mechanics mastered fewer, less gross errors improved coordination

e.g., limb joints controlled independently

refining & basic error detection can be done by the leaner 3. Autonomous Stage.

skill is almost automatic

own error detection & correction

so need less time from the instructor

Motor Learning Unit 4: Attention and learning

234.657+ 132.004 = 72 / 0.0234 =

22.034 * 1.017 = (23.3*33.4) + (345/5.45) = ATTENTION

WE HAVE LIMITED CAPACITY TO ATTEND TO FEEDBACK INFORMATION KAHNEMAN’S MODEL OF SELECTIVE ATTENTION

TOTAL

CAPACITY TO ATTEND IS DIVIDED UP ENDURING DISPOSITIONS

= INVOLUNTARY ATTENTION

MOMENTARY INTENTIONS

= WHAT YOU DECIDE TO ATTEND

TO FOR THAT SITUATION (MOMENT)

ED MI

A) RULES OF INVOLUNTARY ATTENTION (ENDURING DISPOSITION RULES) RULE 1) unexpected stimuli attract our attention

A B C D

Transfer Test Period

Learning Period

TA

C o l u m n A : b l i n d f o l d e d s u b j e c t l e a r n s t o p o s i ti o n fi n g e r o n t a r g e t , b a s e d o n f e e d b a c k f r o m t e s t e r

T R A N S F E R T E S T :

C o l u m n B : w i t h b l i n d f o l d : t h e

s u b j e c t m o v e s h a n d t o t a r g e t

p o s i ti o n o n g r i d

Motor Learning Unit 4: Attention and learning

D e m o n s t r a t e s t h a t p e o p l e fi r s t a n d f o r e m o s t t r y t o g e t f e e d b a c k f r o m t h e i r e y e s

E v e n t h o u g h t h e i r e y e s m a y n o t b e t h e b e s t s o u r c e s o f i n f o r m a ti o n RULE 2) we tend to pay attention to visual information

V i s i o n d o m i n a t e s o t h e r s e n s o r y f e e d b a c k s y s t e m s .

RULE 3) we attend to things which are MEANINGFUL (= understood)

I N S T R U C T I O N A L I M P L I C AT I O N S O F AT T E N T I O N R U L E S

To h e l p l e a r n e r u s e l i m i t e d a tt e n ti o n f o r w h a t i s m o s t i m p o r t a n t R U L E 2 ) w e t e n d t o p a y a tt e n ti o n t o v i s u a l i n f o r m a ti o n

D I R E C T L E A R N E R T O PAY AT T E N T I O N T O N O N V I S U A L F E E D B A C K W H I C H I S C R I T I C A L

R U L E 3 ) w e a tt e n d t o t h i n g s w h i c h a r e M E A N I N G F U L

M U S T M A K E T H E M O S T I M P O R TA N T F E E D B A C K V E R Y M E A N I N G F U L T O

L E A R N E R

Motor Learning Unit 4: Attention and learning

Action (teaching “trick”) Basis

Isolate the learner Remove from more meaningful or unexpected

distractions = enduring dispositions

Use their name often Meaningful gets attention = enduring dispositions Clap, sing, funny sound (these tricks for people

with very limited attention)

Unexpected gets attention = enduring dispositions

Remove any hint of real or perceived danger Meaningful gets attention = enduring dispositions Do not allow parents to watch class Meaningful gets attention = enduring dispositions Remove the ability for student to focus on result

(e.g, fast time, # goals, being first, getting

finished) by removing the ball, target, limiting all to go at same speed, not doing the whole action etc.

SO THAT

Student can focus on how to do the skill correctly

Most meaningful characteristic of performance to the student is the RESULT so they focus on the result.

SO THAT

Performance characteristics (good technique) becomes most meaningful (the only thing they can focus on)

“Trick” the student into doing the skill, by having her focus attention on a meaningful task with a very similar movement pattern.

e.g.,

o Breast stroke kick is:

1. knee bend, feet out, straight leg OR

2. chicken, airplane, soldier o Side stroke arm movement is:

1. reach up, pull down OR Side Stroke:

pick an apple from a tree and put it in your bag

Meaningful gets attention = enduring dispositions

AT T E N T I O N D E M A N D S & P R A C T I C E

Motor Learning Unit 4: Attention and learning

i n t e r m e d i a t e : a d v a n c e d :

F O R A M O T O R S K I L L Y O U T E A C H : f o r b e g i n n e r :

a ) w h a t i s n a t u r a l l y p a i d a tt e n ti o n t o ? b ) w h a t s h o u l d b e p a i d a tt e n ti o n t o ? f o r p r o fi c i e n t p a r ti c i p a n t :

a ) w h a t s h o u l d b e p a i d a tt e n ti o n t o ?

H o w w i l l y o u h e l p t h e m m a k e t h i s t r a n s i ti o n ? R e c e n t s t u d i e s o n a tt e n ti o n a n d d r i v i n g S o u r c e : A A A F o u n d a ti o n F o r T r a ffi c S a f e t y,

h tt p : / / n e w s r o o m . a a a . c o m / 2 0 1 3 / 0 6 / t h i n k - y o u - k n o w - a l l - a b o u t - d i s t r a c t e d - d r i v i n g - t h i n k - a g a i n - s a y s - a a a / ,

h tt p : / / d c . s t r e e t s b l o g . o r g / 2 0 1 3 / 0 6 / 1 7 / a a a - h a n d s - f r e e - d e v i c e s - d o n t - s o l v e - d i s t r a c t e d - d r i v i n g - d a n g e r s /

Cognitive distraction expert Dr. David Strayer and his research team at the University of Utah measured brainwaves, eye movement and other metrics to assess what happens to drivers’

mental workload when they attempt to do multiple things at once.

OSPAN, or operation span, sets the maximum demand the average adult brain can handle. For

the OSPAN, the researchers gave subjects words and math problems to recall later, in the same

order, as a way to anchor the high end of the cognitive distraction scale developed by the

research team

Motor Learning Unit 4: Attention and learning

The levels of mental distraction are represented on a scale:

Motor Learning Unit 5: Augmented Feedback

AUGMENTED FEEDBACK = FEEDBACK FROM AN EXTERNAL SOURCE

K R = i n f o r m a ti o n p r o v i d e d t o t h e l e a r n e r r e l a t e d t o t h e i r o u t c o m e ( r e s u l t s o f t h e m o v e m e n t )

K P = i n f o r m a ti o n p r o v i d e d t o t h e l e a r n e r r e l a t e d t o t h e p e r f o r m a n c e c h a r a c t e r i s ti c s t h a t p r o d u c e d t h e o u t c o m e

Tells the learner what they did right or wrong, to produce the good (or bad) result.

A U G M E N T E D S E N S O R Y F E E D B A C K = h e l p l e a r n e r d e t e c t a n d u ti l i z e w h a t t h e i r s e n s o r y s y s t e m i s u n a b l e t o d e t e c t

U s u a l l y g i v e n d u r i n g p e r f o r m a n c e

W H AT I N F O R M AT I O N T O G I V E W H E N P R O V I D I N G A U G M E N T E D F E E D B A C K ?

P R O V I D E F B O N O N E A S P E C T O F P E R F O R M A N C E F O R L E A R N E R T O F O C U S O N

Task: Complex arm movement with an exact goal time to be met, trying to make the arm movement & arriving back at the start in a required amount of time, not too fast, not too slow

o p e n b o x = H i g h d e t a i l F B = d i r e c ti o n &

a m o u n t o f e r r o r g i v e n

e . g . , 2 s e c t o o f a s t , 0 . 5 s e c s t o o s l o w

fi l l e d t r i a n g l e = L o w d e t a i l F B = o n l y d i r e c ti o n o f e r r o r g i v e n

e . g . , t o o f a s t , t o o s l o w

B E G I N N I N G L E A R N E R : e a r l y i n l e a r n i n g ( t r i a l s 1 - 6 , x 1 0 ) l o w d e t a i l F B f e e d b a c k a s g o o d a s h i g h d e t a i l F B D O N ’ T B O T H E R B E G I N N E R W I T H D E TA I L E D F E E D B A C K

T h e e x t r a d e t a i l o f t h e m o r e p r e c i s e F B c a n ’ t b e u s e d b y t h e p e r s o n

e a r l y i n t h e l e a r n i n g p r o c e s s

Motor Learning Unit 5: Augmented Feedback

I N T E R M E D I AT E L E A R N E R : l a t e r i n l e a r n i n g ( t r i a l s 7 - 1 0 , x 1 0 )

c o n ti n u e d i m p r o v e m e n t ( r e d u c ti o n i n e r r o r ) o n l y p o s s i b l e f o r h i g h d e t a i l g r o u p .

I n l a t e r t e s t w i t h o u t K R t h e h i g h d e t a i l F B g r o u p p e o p l e d i d b e s t . A S S K I L L L E V E L I N C R E A S E S , M O R E P R E C I S E F B I S N E E D E D

D O N O T G I V E F B A F T E R E V E R Y T R I A L

I f y o u g i v e a u g m e n t e d f e e d b a c k a ft e r e v e r y t r i a l t h e p e r s o n d o e s n o b e tt e r, s o m e ti m e s w o r s t , t h a n a u g m e n t e d f e e d b a c k a ft e r s e v e r a l t r i a l s

W H Y ?

O P T I M A L F B F R E Q U E N C Y D E P E N D S O N TA S K , T E A C H I N G T E C H N I Q U E , L E A R N E R .

G R A D U A L LY R E D U C I N G T H E F R E Q U E N C Y O F F B ( F A D I N G ) A S S K I L L L E V E L I N C R E A S E S I S E F F E C T I V E

I n t e r n a l v s . E x t e r n a l C u e s i n y o u r f e e d b a c k ? ? ?

Internal cue: The athlete focuses on his/her body parts and how they move e.g., “rapidly extend your legs”

External cue: The athlete focuses on affecting something in his/her environment. Athlete focuses on the outcome of his/her movement

e.g. “drive the ground away”

Research validates the efficacy of external focus across a wide variety of motor skills.

Further work has shown that external focus is not only important for the novice learner, but has

also shown efficacy in experts.

Motor Learning Unit 5: Augmented Feedback

Jumping

Internal Cue External Cue

 Explode through hips

 Snap through ankles

 Drive hips through head

 Snap the ground away

 Drive belt buckle up

Change of Direction

Internal Cue External Cue

 Hips down

 Feet wide

 Drive through big toe

 Train tracks or wide base

Motor Learning Unit 5: Augmented Feedback

Sprinting: Acceleration

Internal Cue External Cue

 Extend your hip

 Activate your quad

 Stomach tight

 Drive the ground away

 Explode off the ground

Olympic Lifting: Snatch

Internal Cue External Cue

 Drive feet through ground

 Drive chest to ceiling

 Snap hips through the bar

 Push the ground away

 Drive/jump vertical

 Snap and drop under bar

WHY THE SUPERIORITY OF EXTERNAL CUES? The constrained action hypothesis (G Wulf)

Focusing on body movements (i.e. internal) increases consciousness and “constrains the motor system by

interfering with automatic motor control process that would ‘normally’ regulate the movement,”

Motor Learning Unit 5: Augmented Feedback

More internal cues with beginners. As the athlete gains experience and expertise, move on to more external cues.

S a m p l e r e f e r e n c e s f o r i n t e r n a l v e r s u s e x t e r n a l c u e s :

Porter, Jared M. et al. Adopting an External Focus of Attention Improves Sprinting Performance in Low-Skilled Sprinters. Journal of Strength & Conditioning Research. 29(4):947-953, April 2015.

Ducharme, Scott W.; et al, Standing Long Jump Performance With an External Focus of Attention Is Improved as a Result of a More Effective Projection Angle. Journal of Strength & Conditioning Research. 30(1):276-281, January 2016.

Halperin, Israel; et al, The effects of attentional focusing instructions on force production during the isometric mid- thigh pull. Journal of Strength & Conditioning Research. Publish Ahead of Print, POST ACCEPTANCE, 10 September 2015

John Kessel, A Major Change in My Feedback, (Jan. 15, 2016) http://www.teamusa.org/USA- Volleyball/Features/2016/January/15/A-Major-Change-in-My-Feedback#.Vp3Lp72Wy5Q.mailto

Nick Winkelman, Hot Topic: What We Say Matters, Part I https://www.nsca.com/Education/Articles/Hot-Topic- What-We-Say-Matters-Part-I/

Kyle Norman, http://denverfitnessjournal.com/coaching-movement-internal-vs-external-cues/

F O R A S K I L L Y O U A R E T E A C H I N G

D e s c r i b e s o m e F B y o u w o u l d g i v e t o a b e g i n n e r, a n d h o w t h i s w o u l d

c h a n g e a s s k i l l l e v e l i n c r e a s e d

Motor Control Assignment

KIN 410 Motor Control Assignment:

Examination of a motor control issue relevant to my future work with people

For this assignment you will investigate a motor control disorder, or a motor control aspect of exercise science. Students will work in groups of two to investigate a topic of choice, students in a group should have similar career goals or interests. The topic selected must be related to your career goals or interests. For example, a pre-PT or OT student should investigate a disorder they are likely to encounter in practice. A pre-teacher should investigate a disorder that a child in class could have. An exercise science student can investigate any disorder, but some in particular have special exercise implications, such as the role therapeutic exercise plays in the disorder or the exercise capacity of a person with the disorder. Topics that are related to exercise science motor control issues, but are not disorders, are also listed and may be of particular interest to exercise scientists (future athletic trainers, coaches, personal trainers, etc.).

Once a topic has been selected, decide if you will follow the format for a paper on a MOTOR CONTROL DISORDER, or the format for a paper on a MOTOR CONTROL ISSUE (i.e. not a

disorder). For example, a paper on Parkinson's disease would fall into the former category, an examination of PNF stretching would fall into the latter. If it is not obvious what format to follow for your topic, check with Dr. Chalmers.

For an examination of a disorder: The investigation should explain WHAT IS IT? This section may include topics such as the physiology of the normal functioning of the system or structure in question, what has gone wrong, incident rates, and specific populations affected, (not including symptoms). CAUSES or hypothesized causes of the disorder. SYMPTOMS, ensure you include motor control symptoms/effects of the disorder. TREATMENT for the disorder. In this section do not emphasize the role that you will play in your future profession (e.g., as PT or teacher, etc.), but discuss the range of potential treatments that the individual with the disorder may be receiving from the variety of health care professionals that may be involved, because you need to be aware of the treatments this person is receiving (e.g., surgery, drugs,

psychological) when you plan your work with him/her (the next section). Remember that even if there is no cure for the disorder, there are treatments the person receives. Finally (and very importantly), a discussion of HOW I WOULD WORK WITH A PERSON WITH SUCH A DISORDER.

In the "treatment" section you have discussed the full spectrum of the individual's treatment,

one aspect of which will be your role as a therapist or an educator etc. In the " how I would

Motor Control Assignment

site for an example. KEY ISSUES YET TO BE RESOLVED should be discussed. This section looks FORWARD at what needs to be figured out, based on what has been done. Finally (and very importantly), a discussion of HOW I WOULD USE THIS MOTOR CONTROL INFORMATION WHEN WORKING WITH A PERSON IN MY CAREER must be included. Do not write this final section in first person, write it as a information sheet for others in your field to read and learn from. For this form of the paper a major emphasis is on your REVIEW of current knowledge on your topic.

Note in the grading sheet that the review is in three sections for grading because the review is heavily weighted.

For both paper formats: You will be writing a report on your topic in a format that can be called a “fact sheet”, “brief report”, or “information brochure”. This format is a very popular in our field to communicate health and fitness information to the public. For example, you may be asked to produce a short handout to be available to clients on an issue of importance. For example, think of the information brochures you may have picked up in a doctor’s office or an exercise facility. It is necessary for you, as the professional in the field, to learn how to take lots of up-to-date information on a topic, and condense it and present it to a client, patient, etc.

who does not have the time or desire to read a full length research report. One of the biggest challenges in writing this way is to becoming a “word efficient” writer. It is easy to write a six page review. But to write almost the equivalent information in one third the space requires that you be very efficient in what you say and how you say it. After you write your first draft of your paper it will likely be far too long. You then examine everything you wrote and ask yourself, “is this fact or level of detail essential?”, “is this essential idea said in the most efficient way

possible?”, “can I eliminate some words in this sentence and not loose the meaning?”. It is very important you reduce the length of you report by eliminating unnecessary words, not important details. A summary or conclusion section is not needed at the end of the report. See the sample papers on the course web site for examples of how a lot of information can be packed into a few words. Warning: Do not deceive yourself, or try to deceive your instructor, thinking that a “brief report” requires less research time or thoroughness than a traditional research paper. The need for research is just the same. The difference between the “brief report” and a full research paper (e.g. as done in KIN 301) is in the writing. In a “brief report” you must be extremely concise, precise and efficient with your writing, to effectively communicate the necessary high level of information with a lot fewer words. The writing of a “brief report” is really more challenging than a traditional term paper because you don’t have the room for unnecessary information, and you can’t hide sloppy writing or poor organization as easily.

Write at a technical level assuming your reader has taken university level anatomy, and basic physiology. So you do not need to explain what a neuron, a motor unit, muscle, blood etc. is. The reader already has this knowledge.

Each of the underlined topics above corresponds to a section in the grading sheet for evaluation of the paper. To help organize your paper it is required to have a heading and a specific section that addresses each of the topic areas underlined above (with the exception of the first major section heading label not being required in the ISSUE paper, as described above).

If you exclude a section heading and it's required discussion, or put the required discussion into

other sections of the paper, you will be scored zero points in that part of the evaluation. If you

Motor Control Assignment

section "how you would ...work with a person..." can take different meanings depending on the disorder and your career direction. For example, you could discuss the physical or occupational therapy this person would receive at home or in a clinic, if that is your career direction. You could discuss special considerations for how this person could be included and taught in

classroom if your direction is teacher education. You could discuss the physical capabilities that could (should?) be expected from the person, and how exercise can help, or hurt, their

condition and their overall physical health, if your direction is exercise science. In all cases this final section (like all of your paper) must be research based and be referenced to sources, people are not interested in what you think should be done, but in what experts you have learned from think. Citations are critical here to justify your method of working with such a person. In all sections, your work should emphasize motor control (i.e., neurophysiology and muscle physiology) aspects of your topic, not biomechanical, cardiovascular, behavioral etc.

For this brief report format you will use a modified APA citation method. See the course web site for sample assignments including examples of the bibliography and in text citation method in the prostate cancer example. Specifically you must cite your references as follows:

 Create a bibliography list using all of the APA rules for how to cite a source in a reference list, and sequence the list in alphabetical order, by author name.

 Add numbers to the reference list to identify each reference.

 Cite the information in the text using the numbers as superscript immediately following the related information in the text.

Your report must have a minimum of seven references. Use the biomedical and educational databases (& other sources) for your literature search. Education students must not only rely upon education sources, at the most 3 can be from the education (nonbiomedical) literature.

Within the minimum of seven references you must have:

 At least four peer reviewed journal articles, any number more than this is encouraged. Electronic journals are not considered to be web sites, they are journals.

 A maximum of one book.

 A maximum of three highly reputable web sites. Web sites may only be national

professional organizations (e.g., AMA), government web sites (e.g., NIH, CDC), or

Motor Control Assignment

 For references you provide for this assignment, citation of the class lecture notes as a reference is not allowed.

You must ensure that you provide a reference for all statements you make in your paper that are not your own original thought. Also, you must use the most up-to-date information

available as your sources. Biomedical information that is greater than 10-15 years old is likely out-of-date (Would you want your doctor or teacher to use only information that he/she learned 20 years ago and has not updated since? Staying current in your profession is crucial!).

Cite only sources that you obtain and read completely. Do not use a reference that you only obtain the abstract for. You are not required to submit copies of your references with this paper. During evaluation of your paper, however, Dr. Chalmers may request that you provide your complete references within 24 hours, so keep them handy after writing the paper.

See the grading sheet for the term paper, in Dr. Chalmers lecture notes for additional

description of criteria used in grading the paper. A grading sheet must be removed from the last page of the lecture notes package and included as the last page of your paper. PLEASE,

remember to staple your paper.

The report is to be 1.5 pages of typed single spaced text with a minimum font size of 12 point, this does not include the reference list page. You do not need a title page (put names and title in header on the first page. You must have one extra open line space before each major section heading, and the title must be at the top center of the first page of the text (see the samples on the course web site). The margins are to be 0.75 to 1 inch on all sides. The required length is to be rigidly adhered to. This may seem very restrictive and unreasonable, but when asked to produce an information brochure in a job, you will be given strict

requirements that must be adhered to (e.g., fits on one 3 fold piece of paper, margins of ½ inch from edges and folds, font size 12 New York, but do not actually produce you report as a three fold brochure), your job is then to meet those requirements to produce the needed product.

The report must be well laid out and easy to read (see the samples on the course web site).

Accordingly, when getting your report to fit the required length, you must focus primarily on the content and the writing, not on page layout tricks to shrink or expand the length. The font must be clearly printed, without defects that low cost printers may produce.

Some sample reports from previous terms are available on the course web site for you to view.

You may include a bullet list of some details you want to summarize. A bullet list must have an introduction sentence to it, explaining what is being listed. An introductory word like

“Symptoms” does not suffice as an introduction to a list. A list must also be laid out well to not waste page space. Below are examples of good and bad tables.

A good table. Good introductory sentence and laid out to not waste page space.

Motor Control Assignment

A poor table. Good introductory sentence, but laid such that valuable page space on the right is not used.

A poor table. Good introductory sentence, but laid such that valuable page space on the

left is not used.

Motor Control Assignment

Do not waste space using big headers. Below is an example of a paper in which a lot of space was wasted at the top of the first page. It would have been better to put the student names in one line in the page header. The date is not needed.

Do not leave a heading for a section alone at the bottom of a page, with no text from it’s paragraph below it (see sample below).

At the top of the grading sheet fill in your names, topic, and if the paper is on a DISORDER or ISSUE. This will ensure that the correct parts of the grading form are used when evaluating your paper. The grading sheet must be attached as the last page of the assignment. Sample reports are available on the course web page.

You work in groups of twos so you will gain experience working in a team to produce a

product. This requires coordination, cooperation and communication, all essential skills to have

in the work place, but skills that are not practiced and improved through work alone on a

Motor Control Assignment

project. Further, we all know that two heads are better than one, so the team will come up with better and more ideas. If you find that a partner in a group is not contributing to the team, then discuss this problem first with the partner, then, if needed, with Dr.

Chalmers as soon as possible so that options can be explored. If fair cooperation between the students can not be achieved, then the project will be divided in half, under Dr. Chalmers’ direction, and each student in the “team” will be responsible for half the paper, and will obtain their full grade from the half he or she does. This way one student is not writing all or most of a paper, and another student gets a grade largely from the first student’s effort. Finally, all people on the team are to proof read the paper before it is submitted. A paper that is only checked by a spelling checking program may contain grammatical errors, or errors of disjointed thought or poor organization. Only human checking by a person other than the original author can detect these sorts of errors.

Written report due date: The due date is listed in the course outline. Papers submitted after start of class on this date lose 10% of the maximum total marks per day, including each weekend day. Penalty for over or under length paper: For each ¼ page, or portion thereof, over or under required length, your paper score has subtracted from it 10% of the total grade possible on the assignment.

Presentation on your topic: Each student will do a short presentation on their research topic to other students. All of the students in the group that wrote the paper will present the paper, to separate groups. The exact length of the presentation will be determined when we know how many papers are to be presented, and the size of the class. Expect that the

presentation will be 5-7 minutes in length. The date of this presentation is in the course outline.

The presentation will be graded on participation. Full points will be given to students who participate. There will be no opportunities for presentation other than on the day the whole class does presentations. Late presentations with a reduction in grade will not be allowed. (As with all assignments, only substantiated medical absences or other well documented absences due to extenuating circumstances will permit a change in the due date for an individual).

SAMPLE TOPICS

You are not restricted to these topics, they are intended to stimulate your thoughts on a

topic of interest to you. You are free to modify these topics or select any other motor control

related topic of interest that you know about that you would like to investigate. All topics must

Motor Control Assignment

Duchenne muscular dystrophy (children primarily) *

Myotonic dystrophy (adults primarily)

Multiple sclerosis * Guillain-Barre syndrome

Spinal cord injury *

Epilepsy *

Clumsy child syndrome, a.k.a.

developmental coordination disorder *

Downs syndrome hypotonia *

Diabetic neuropathy Parkinson’s disease

Autism* Restless Leg Syndrome

Touretts syndrome Sensory adaptation to blindness

Essential Tremor (one of the most prevalent neurological disorders in the world, afflicts all ages)

Friedreich’s ataxia or cerebellar ataxia or

locomotor ataxia (Ataxia = movement irregular &

disordered in direction)*

Charcot-Marie-Tooth disorder Sciatica

Quadriceps activation deficit following knee replacement (Central Activation Deficit)

SAMPLE MOTOR CONTROL EXERCISE SCIENCE TOPICS

Muscle coordination following anterior

cruciate ligament injury

Neuromuscular electrical stimulation (NMES) to strengthen injured muscles

Balance & falls in the elderly Proprioception & prophylactic knee bracing Nervous system contribution to fatigue of

muscles (Neural fatigue)

Functional electrical stimulation of paralyzed extremities

Proprioceptive training, of healthy athlete and/or rehabilitation following injury. Is it effective? (Not just a discussion of

exercises to do)

Motor control (e.g., proprioception, coordination, motor unit control) during neuromuscular fatigue.

Could include discussion of injury implications.

Proprioceptive from the ACL &

rehabilitation following ACL injury

Maximum voluntary contractions (MVC). Can people voluntarily activate 100% of their potential muscle force?

Arthrogenic muscle inhibition after joint damage

Reflexes associated with the knee joint, how these reflexes change following injury or laxity of the knee

Muscle fiber type changes with injury (e.g.

immobilization, electrical stimulation, spinal cord injury)

Scoliosis

The affect of exercise on neural and cognitive function in the elderly

Locomotion (walking) rehabilitation in neurological populations (stroke, spinal cord injury), including the use of body weight support systems

* These disorders are particularly applicable to education situations.

@

Exercise science students can examine any topic, but the role of exercise may be especially

applicable to these disorders, or any of the topics in the second table.

Motor Control Assignment

Motor Control Assignment Grading Sheet

NAMES: TOPIC:

Report is on a DISORDER or a MOTOR CONTROL ISSUE (circle one)

Exceptional Obvious extra

& outstanding effort in research &

Good Correct facts at sufficient detail to explain issues, and

presentation

Some Improvement Needed Facts & detail explain issues, but

more detail, easily possible, or some explanation confusing.

Presentation with some

Weak Facts & detail do not explain issues, or some

significant errors.

Presentation with very N e ed s H e lp ! M is si n g

5 4 3 2 1 0

FACTUAL CONTENT

plain description: for a paper on a disorder italic descrip.: for an “issue” paper

5 4 3 2 1 Comments

WHAT IS IT? May include physiology of the normal system, what has gone wrong, incident rates, populations affected, (not symptoms) Review critical issues in the topic - using subheadings

CAUSES or hypothesized causes

Review critical issues in the topic - using subheadings

SYMPTOMS, including motor control symptoms/effects

Review critical issues in the topic - using subheadings

TREATMENT (not emphasizing my role) Key issues yet to be resolved

HOW I WOULD WORK WITH A PERSON WITH SUCH A DISORDER

How I would use this motor control information when working with a person in my career

PREPARATION OF PAPER

Paper and paragraph organization of material, use of required headings to organize material.

Spelling, punctuation, & sentence structure Minimum 7 references: >= 4 journals, <=1 book,

<= 3 quality web sites, up-to-date information Reference list follows APA modified sample style. Citations within paper follow sample style

1.5 pages, no wasted space _____ Grading sheet attached _______

General Comments:

Motor Control Section 1: The Stretch Shortening Cycle (a.k.a. plyometric movements) Unit 1: Anatomy & Physiology

Flow of information in a neuron is:

1) reception of information (usually on the dendrites)

2) summation of all the incoming signals (some excitatory (+) & some inhibitory (-) ) to see if a signal should be sent out the axon (summation occurs at the axon hillock) 3) output signal sent down axon to act

The ALPHA () MOTOR NEURON has an axon which innervates skeletal muscle ventral root is all OUTGOING neural information

= EFFERENT path

dorsal root is all INCOMING neural information

= AFFERENT path

THE CELL BODY (SOMA) FOR A SENSORY NEURON IS IN THE DORSAL ROOT GANGLION (DRG) the dorsal & ventral roots join before they emerge from the bony vertebrae to form a MIXED nerve of afferent & efferent axons

BRAIN & BRAIN STEMSPINAL CORD

VENTRAL ROOT DORSAL

ROOT

Two ways for action potentials to get started

1) one neuron has thousands of other neurons sending presynaptic terminals to synapse

on that one POST SYNAPTIC cell

Motor Control Section 1: The Stretch Shortening Cycle (a.k.a. plyometric movements) Unit 1: Anatomy & Physiology

some input signals are EXCITATORY (+)

= INCREASE THE PROBABILITY THAT THE POSTSYNAPTIC CELL WILL FIRE AN ACTION POTENTIAL depolarize the cell toward threshold for firing an AP

2

WAY TO GENERATE ACTION POTENTIALS

Sensory receptor is activated by a stimulus and generates an action potential to be propagated in the afferent neuron to the spinal cord

SENSORY RECEPTOR

INPUT:

ENERGY

OUTPUT:

ACTION POTENTIALS

DRG

touch receptor dendrite

axon

SPINAL CORD

SOMA FOR A SINGLE

SENSORY NEURON IN THE

DRG. Each DRG contains

hundreds of these sensory

neuron cell bodies

Motor Control Section 1: The Stretch Shortening Cycle (a.k.a. plyometric movements) Unit 1: Anatomy & Physiology

Each action potential is the same size.

How does nervous system know about intensity of stimulus? (e.g. hard versus soft push on skin) Draw a diagram showing the two axons needed to carry a signal from a skin pressure receptor, to the spinal cord (the 1st axon) and then (2nd axon) back out to the muscle. At the start of each axon, and at the start of the muscle describe the process which starts an action potential after each synapse (or at the receptor). Remember to label everything, and to do an

anatomically correct diagram of the spinal cord in cross section showing the route of the axons.

Motor Control Section 1: The Stretch Shortening Cycle (a.k.a. plyometric movements) Unit 2: Sensory Receptors

Proprioceptors

detect body position in relation to body itself, and environment

WHAT ARE MUSCLE SPINDLES AND WHAT AFFERENT FEEDBACK DO THEY PROVIDE?

EXTRAFUSAL MUSCLE FIBERS form the bulk of a muscle and are the muscle cells you see & feel easily

MUSCLE SPINDLE spindle shaped = fusiform shape the muscle spindle lies in PARALLEL with the extrafusal fibers

education.vetmed.vt.edu/.../ Lab10/Examples/exspindl.htm

STRUCTURE OF A SINGLE SPINDLE

citd.scar.utoronto.ca/BGYC21/ scmedia/Index.html

spindles contain tiny muscle fibers = INTRAFUSAL FIBERS

TYPE IA AFFERENT IS WRAPPED AROUND THE EQUATORIAL REGION OF THE INTRAFUSAL FIBERS WHAT STIMULATES THESE TYPE IASENSORY NEURONS AND GETS THEM TO FIRE ACTION POTENTIALS ?

lengthening of the EQUATORIAL REGION OF intrafusal fibers deforms the nerve endings and causes action potentials to fire.

WHO CARES ABOUT THE LENGTH OF THESE INTRAFUSAL MUSCLE FIBERS?

EXTRAFUSAL MUSCLE FIBER

INTRAFUSAL

FIBER Ia

fixed object

1) MUSCLE STRETCH DEMO

Q: what happens to equatorial region of spindle intrafusal fibers?

Q: what happens to afferent output from the spindle?

Q: what is this telling the CNS?

Motor Control Section 1: The Stretch Shortening Cycle (a.k.a. plyometric movements) Unit 2: Sensory Receptors

What information is the spindle coding (telling) for the CNS?

PASSIVE MUSCLE LENGTH CHANGE DEMONSTRATION

top: EMG of finger extensor muscle (MUSCLE IS QUIET = PASSIVE MOVEMENT) next line: finger position. Line down = finger up = short muscle

Line up = finger down = stretched muscle bottom 2 lines: firing rate of spindle Ia afferent

observe: with passive movement of the subject’s finger by an experimenter Line down, finger up, short muscle = low Ia firing rate

as line moves up, finger moves down, muscle lengthens = increase Ia firing rate Line down again, finger up, short muscle = low Ia firing rate

What would happen to spindle firing rate with a FASTER stretch?

0.00 0.18 0.36 0.54 0.71 0.89 1.07 1.25

0 10 20 30 40 50

0 100 200 300 400 500 600 700 800 900 Biceps Ia firing rate and muscle length - slow stretch

MUSCLE LENGTH Ia FIRING RATE

Time (seconds)

M u sc le L en g th ( m m ) Ia f ir in g r at e (p u ls es p er s ec o n d )

Biceps Ia firing rate and muscle length - fast stretch

50

800

900

Motor Control Section 1: The Stretch Shortening Cycle (a.k.a. plyometric movements) Unit 2: Sensory Receptors

www.med.unsw.edu.au/.../School/ Postgrad/PaulM/Kinaesth.htm

Sensory events from

external environment

BRAIN & BRAIN STEMSPINAL CORD

VENTRAL ROOT DORSAL

ROOT

Muscle

Displacement Sensory

consequences of movement

Afferent input

Motor Control Section 1: The Stretch Shortening Cycle (a.k.a. plyometric movements) Unit 3: Stretch Reflexes

The Stretch Reflex

Holding a cup full of water in your upward turned palm (elbow @ 90 degrees) a crow lands on your palm to drink from the cup

Q1: What happens to your hand & elbow position?

Q2: What happens to the output from the biceps spindle?

WHAT IS THE EFFECT OF THIS SPINDLE OUTPUT?

Ia afferent synapses (excitatory synapse) onto all of the  motor neurons innervating the HOMONYMOUS (same) muscle

Complete the following illustration to indicate what happens during the stretch reflex

Load

muscle length

Ia afferent discharge

alpha MN discharge

desired shorter

longer low high

crow lands

Motor Control Section 1: The Stretch Shortening Cycle (a.k.a. plyometric movements) Unit 3: Stretch Reflexes

See: Zuur AT, Lundbye-Jensen J, Leukel C, Taube W, Grey MJ, Gollhofer A, Nielsen JB, Gruber M. Contribution of afferent feedback and descending drive to human hopping. J Physiol. 2010 Mar 1;588(Pt 5):799-807.

How does an exercise scientist, PT student, trainer or athlete use a knowledge of stretch reflexes?

Description of experiment and results.

Subjects perform three of each of the following types of jump:

1. Squat jumps (SJs). The SJ starts with the subject in a squatted position, then the upward jump is initiated.

2. Counter movement jumps (CMJs). The CMJ starts with the subject standing with knees extended, then the knees are flexed followed by immediate knee extension.

3. CMJs starting on a 12 inch elevated platform. The platform start for the CMJ has the student stepping off the block and landing on the floor with both feet at the same time, and then immediately jumping upward.

The height jumped is record and there is alternation between jump styles to reduce order effects (fatigue and practice/learning). It is ensured that the subject does not perform any dip movement prior to the SJ. All jumps are completed with the hands over the head before and during the jump (so arm movement does not contribute to jump height and the

subjects hands are in position to push the vertex device at the maximum height reached).

The maximal jump height is always attempted.

Best jump scores:

Squat Jump Height Counter Movement Jump Height

Block Jump, Counter

Movement Jump Height

Motor Control Section 1: The Stretch Shortening Cycle (a.k.a. plyometric movements) Unit 3: Stretch Reflexes

Subject D 3 4 4.5

Subject C 3 5 6

Subject K 2.5 3 2.5

Subject M 8 12 11

Subject S 4 4 4

Q1) Was there an increase with the CMJ compared to the SJ?

Q2) If there was an increase, WHY was there an increase?

Q3) What was the effect of increasing drop height on jump height?, WHY?

Q4) Why might one person produce the greatest jump height from a CMJ starting on the floor, while a second person produces the greatest jump height during the CMJ with a drop off the block?

Sensory events from

external environment

BRAIN & BRAIN STEMSPINAL CORD

VENTRAL ROOT DORSAL

ROOT Segmental spinal

network Muscle

Displacement Sensory

consequences of movement

Afferent input