Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biomechanics > Neurological Considerations for Movement > Flashcards

Neurological Considerations for Movement Flashcards

1
Q

Peripheral Nervous System

A

Sensory Neurons (Dorsal Side)
- Receive information

Motor Neurons (Ventral)
- Send information

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Motor Unit

A

Nerve cell and all muscle fiber innervated

All of none principal

All fiber types (I,IIa,IIb)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Motor Pool

A

Groups of motor neurons that innervate a particular muscle

Tongue and hand have greater pools for precision

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Tetanus

A

Action potential sequenced together – tetanus (constant tension)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Muscle Fiber Types

A

Type 1 - SO
Type 2a - FOG
Type 2b - FG

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Type 1 - SO

A

Slow contraction times (>70 ms)

Generate little tension

Highly fatigue resistant

Maintain posture

Endurance athlete

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Type IIa – FOG

A

Fast contraction times (30-50 ms)

More fatigue resistant than type IIB

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Type IIb – FG

A

Rapid contraction times (30-40 ms)

Innervated by alpha motor neurons

Large neuron to fiber ratios

Power athlete

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Recruitment

A

Tension generated by size and number of moto units recruited

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Order of activation for isometric tasks

A

T1 -> TIIa -> TIIb

May change on task performed may activate Type 2 or synchronous with Type 1 (Ballistic)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Asynchronous activation

A

Activation is temporally spaced but summed with preceding motor unit activity

Want to turn on muscle but can’t have all areas of the muscle active at the same time; different areas are used. Specific to low loads and endurance events

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Synchronous activation

A

Large and small motor units activated together
- Ballistic movements, adaptations from weight training
- Routine participation may cause change in recruitment order

Neurologically very difficult to get synchronous activation on a 1 rep max.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Frequency Coding (Firing Rate)

A

High frequency can induce high tension production

Also called rate coding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

During isometric tasks - Small vs Large Muscles

A

Small muscles (ex: hand)
- All units activated when at 30-50% maximum voluntary contraction to increase force, increase firing rate
- Less motor pools

Large muscles (ex: quadriceps)
- Still recruiting motor units at 100% maximum voluntary contraction to increase force
- More fibers per motor unit make it harder to recruit all at motor units in the same motor pool.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Implications of Muscle Testing

A

Hard to know if someone got more efficent at test or better at recruiting

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Reflexes

A

Involuntary response to stimuli

Quick reflex response to muscle fibers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Monosynapatic Reflex Arc

A

When sensory neuron is stimulated, it facilitates the stimulation of a spinal cord neuron

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Types of Reflexes

A
  • Myotactic Reflex (Stretch Reflex): Causes contracion of a muscle being stretched (Knee Jerk Reflex)
  • Flexor Reflex: Initiated by painful stimulus; Causes quick withdrawal/ flexion of the limb
  • Cutaneous Reflex: Causes relaxation of muscle with heart or massage
  • Propriospinal reflexes: Reflexes processed on both sides and at different levels of the spinal cord; 4 Types: Crossed Extensor Reflex, Tonic Neck Reflex, Supraspinal Reflex, Labyrinthine Righting Reflex
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Crossed Extensor Reflex

A

Causes extension of flexed limb when contralateral limb rapidly flexes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Tonic Neck Reflex

A

Causes flexion or extension of the limbs when head flexes or extends respectively

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Supraspinal Reflexes

A

Aka Deep Tendon Reflexes
- Reflexes brought into the spinal cord but processes by brain
- Ex: Patella Reflex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Labyrinthine righting reflex

A

Causes body to return head to neutral positions when the body is tilted or spun

23
Q

Proprioceptors

A

Main sensory receptors for muscle

Sense change in joint position, muscle length, or muscle tension

Can be damaged during injury (May or may not fully recover)

24
Q

Muscle Spindle

A
  • Monitors muscle length
  • Intrafusal fibers (Fibers inside the muscle spindle (in line with muscle fibers; senses then sends signal out and receives one back on what to do; safety mechanism))
25
Q

Types of Intrafusal Fibers

A
  • Nucleat Bag Fibers
  • Nuclear Chain Fibers
26
Q

Nuclear Bag Fibers

A

Intrafusal fibers with a **large clustering of nuclei in the center **

Type Ia afferent neurons exit from middle portion of the fiber (primary afferent)
- Respond to stretch by initiating stretch reflex, velocity dependent (must be quick; done quickly results in contraction); Protective; Contraction

27
Q

Nuclear Chain Fiber

A

Intrafusal fiber with nuclei arranged in rows

Both Type Ia & II sensory neurons exit from this fiber (primary and secondary afferent)

Type 1a: Respond to stretch by initiating stretch reflex; Quick stretch; quick then done; Protective; Contraction
- Ex: Stretch Reflex

Type 2: Feedback does not diminish with time (not velocity dependent), can cause **relaxation in muscle being stretched; Does NOT diminish with time; NOT Velocity dependent **
- Slow and sustained
- Ex: Therapeutic Stretching (Chronic change in length through stretch)

28
Q

What influences muscle spindle activation?

A

Gamma motor neuron: Innervates contractile ends of muscle spindle

Gamma bias: Readjustment of muscle spindle length by contracting ends of intrafusal fiber

Gamma Loop: Reflex arc that works with stretch reflex
- Includes afferent, gamma, and alpha pathways

This can change the threshold needed (the length change) for this type of reflexive behavior

29
Q

Stretch Reflex (Autogenic Facilitation)

A

Facilitates muscle contraction (via muscle spindle) of a muscle being stretched

During this activation the antagonists relax allowing agonists to produce joint motion (Reciprocal inhibition)

30
Q

Plyometrics

A

Autogenic facilitation = 25-30% of force output

Elastic Energy = 70-75% of force output
**Big driver here!!!!! **

31
Q

Golgi Tendon Organ

A

Monitors Muscle Tension (Active Tension)

Extrafusal fibers
- Fibers outside of muscle spindle

Inverse stretch reflex
- Initiated by high tension in muscle
- Inhibits contraction of muscle via GTO
- Causes relaxation of a vigorously contracting muscle (Protective)

During treatment with a patient must train the muscles to inhibit the reaction from GTO that is trying to relax the muscle after a surgery or injury

32
Q

Force - Muscle

A

Countermovement, quick, use elastic energy = more maximal effort

Trying to get 1a afferent response

33
Q

Accuracy

A

Perform movement slower, don’t use elastic energy, don’t use stretch reflex = precise movement

34
Q

Joint Sensory Receptors

A

Sensors monitor Joints

Respond to pain, “Swelling”

Ruffini ending
- Sensory receptor in joint capsule that response to change in joint position

Pacinian corpuscle
- Sensory receptor in skin stimulated by pressure

Reason we don’t like swelling
- Edema effects ability to move and sensation
- Very small amounts have large effects

35
Q

Proprioception - Definition

A

Joint position sense or threshold to detect motion

Involves supraspinal processing of input from peripheral receptors

36
Q

Joint Position Sense and Mechanoreceptors

A

Less Active receptors effects joint position with increase in errors

37
Q

Effect of Resistance Training on Neurological (Input/Output People who don’t normally workout)

A

Neural adaptations during the first 4 weeks of training

Strength increases significantly due to neural adaptation significantly increasing

Teach how to use muscles and limit GTO
- Hypertrophy occurs much later past 4-6 weeks

38
Q

Neuroloigcal Implications to Strength Training

A
  • Significant gains within 4 weeks of training (Due to neuro)
  • Neural adaptations to training (Reduction in inhibition - GTO; Increased neural facilitation and synchronization
  • Bilateral deficit (Loss of both force and neural output through bilateral training; Train one limb at a time leads to greater force output but doesn’t transfer to specificity)
  • Overall decision to train asymmetrically or bilaterally should follow the specificity principle (Ex: Football - Bilateral; Tennis - Unilateral)
  • Cross Education - train opposite limb to get less fatigue on untrained limb; Upper body better than lower body
  • Patterns of limb movements (Flexors/Extensors)
  • Warm up (5-10 min; increases motor unit activity)
  • Opposing muscle groups in sequence (Neural Benefits)
  • Immobilization (Decreases motor unit activity)
  • Inflammation (Decreases muscle acitivation and muscle strength)
  • Plyometric exercises (Uses “autogenic facilitation” (25-30% of force output) and elastic energy (70-75% of force output) )
39
Q

Neurological Implications to Stretching

A

Static (slow sustained stretch) vs ballistic stretching
Static:
- Minimize muscle spindle activation – Type 1a afferents
- Stimulation of Type 2 afferents of muscle spindle – relaxation
- Extreme stretch – GTO (inverse stretch reflex); Not as much data supporting this

Warm + Stretching
- Improve plasticity of tissues

40
Q

Does stretching reduce an injury?

A

Unknown

41
Q

Time to Stretching

A

Largest effect >60s

Very inflexible: 6-10 minutes??

Put weight on knee for long period of time

42
Q

What is PNF?

A

Contract – Relax (PNF – proprioceptive neuromuscular facilitation)

Used to stimulate relaxation

“Tricks” muscle spindles (Type 1a)

Pushing and talk back through ROM or keep him at end ROM then bring back relax and push further

43
Q

Agonist

A

Muscle responsible for a specific motion

Prime vs assistant
- Elbow flexion (Biceps-prime, brachialis-assitant)

Muscles can have additional roles
- Shoulder flexion (Anterior deltoid-prime, biceps-assitant)

44
Q

Anatagonist

A

Oppose action of the agonist

Elbow flexion

Biceps – agonist

Triceps – Antagonist

45
Q

Reciprical inhibition

A

Allows for movement of one muscle group to move (Ex: Quads) by inhibition of hamstrings

46
Q

When does simultaneous contraction of agonist and antagonist occur?

A

Cerebral Palsy (Wasteful metabolically)

E-stim

47
Q

Synergy

A

Cooperative role of two or more muscles to procuce the same action

48
Q

Helping Synergists

A

muscles with a common action in one place, opposing action in other planes

Ulnar flexion (wrist)
- Flexor carpi ulnaris/Extensor carpi unlaris
- If one is damaged leads to favor it the direction of good muscle

Lateral flexion (trunk)
- Obliques

49
Q

True

A

Requires a multi-articular muscle and a muscle that opposes this action at one or more joints (but not all joints)

One muscle stabilizes, one acts

Making a fist
Wrist flexors/extensors

Hamstrings: knee flexion without hip extension
Requires hip flexors

50
Q

How do we know muscles are Active?

A

Logic or Palpation
EMG
Ultrasound

51
Q

Logic or palpation - Active Muscles

A

Insertions of muscle

Joints crossed

Movement (planes/axes)

52
Q

Electromyography (EMG) - Active Muscles

A
  • Neural
  • Measures voltage differences between two sites (Idea of recruitment when performing an activity)
  • Summation of all motor units activation
  • Electrodes on/in muscle to determine motor unit activity (How much impulses are going to muscle)
  • Fast twitch will be much higher than slow twitch
  • How many muscle fibers we have firing
  • Tells us the sequence of muscle activity
  • Amount of tension??? (None! **Only tension under isometric positions. **)
53
Q

Ultrasound - Active Muscles

A

Emerging method! Can measure cross sectional area change

Biomechanics (20 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions