Musculoskeletal System Flashcards
(125 cards)
1
Q
What is the Agonist muscle?
A
The primary muscle that causes the movement e.g. Biceps Brachii during the lifting phase of a Bicep Curl
2
Q
What is the Antagonist muscle?
A
The muscle opposite the Agonist muscle that lengthens and relaxes during a movement e.g Tricep Brachii during the lifting phase of a Bicep Curl
3
Q
What is a Synergist muscle?
A
A muscle that assists the Agonist during a movement e.g. hamstring assisting the gluteals during hip extension
4
Q
What is a Fixator muscle?
A
A muscle that contracts during a movement to keep a joint stable e.g. the mid trapezius and rhomboids stabilise the shoulder during a shoulder press
5
Q
What are the 3 types of muscle?
A
Cardiac
Voluntary or Skeletal
Involuntary or Smooth
6
Q
Where does Skeletal muscle attach to?
A
Bones
7
Q
Why is Skeletal muscle sometimes called Striated?
A
Because under a microscope you can see striations of bundle like tissue
8
Q
Why are Skeletal muscles Voluntary?
A
Because you consciously choose to use them during movement
9
Q
Where is Cardiac muscle located?
A
The Heart
10
Q
Is Cardiac muscle Striated?
A
Yes
11
Q
Is Cardiac muscle voluntary or involuntary?
A
Involuntary
12
Q
Does Cardiac muscle have any anaerobic capacity?
A
No
13
Q
How much of the oxygen in the coronary arteries does the heart use at rest?
A
70-80%
14
Q
Is smooth muscle striated?
A
No
15
Q
Where is smooth muscle located?
A
In Viscera structures such as blood vessels and the digestive system
16
Q
What is the function of smooth muscle?
A
To assist with the flow of blood and food
17
Q
Is smooth muscle voluntary or involuntary?
A
Involuntary
18
Q
How does the amount of fibres in a muscle change during its life?
A
It doesn’t change
19
Q
What happens to the muscle fibres during Hypertrophy?
A
The fibres get bigger
20
Q
What is muscular Atrophy?
A
A reduction in the size of muscle fibres
21
Q
What are the three layers of connective tissue surrounding a muscle?
A
Outer Epimysium, Central Perimysium and Inner Endomysium
22
Q
What is the Epimysium?
A
The Epimysium is the outer covering of the whole muscle
23
Q
What is the Perimysium?
A
The perimysium is the tissue that covers a bundle of fibres within the epimysium
24
Q
What is the Endomysium?
A
The sheath surrounding each muscle fibre/cell
25
What is a bundle of muscle fibres called?
Fascicle
26
What do the Perimysium, Epimysium and Perimysium form when they come together at the end of a muscle?
A Tendon or a broad sheet called an Aponeurosis
27
What do a Tendon or Aponeurosis connect to?
Bone (Periosteum)
28
What does each Muscle Fibre contain?
Myofibrils and a fluid called Sarcoplasm
29
What are the repeating units of Myofibrils called?
Sarcomeres
30
What smaller structures are the Myofibrils filled with?
Myofilaments
31
What are the two types of Myofilaments?
Myosin & Actin
32
Is Myosin a thick or thin filament?
Thick
33
Is Actin a thick or thin filament?
Thin
34
What are the 4 types of muscle depending on Fascicle arrangements?
Parallel muscles, Convergent muscles, Pennate muscles and Circular muscles
35
How are the Fascicles arranged in a Parallel Muscle?
Parallel to the long axis of the muscle
36
What makes a parallel muscle Fusiform?
Having a Tendon at one or both ends rather than Aponeuroses
37
What shape are Fusiform muscles?
Spindle shaped with a wider belly
38
How much can a muscle cell contract?
By about 30%, so a parallel muscle can also contract by 30% as the fibres are parallel to the long axis
39
How are the Fascicles arranged in a Convergent Muscle?
Spread over a broad area like a fan coming back to a common attachment e.g. Pectorals
40
Why is a Convergent Muscle versatile?
Because different sections can be contracted to pull in different directions
41
What negatives come with the versatility of a Convergent Muscle?
Because the fibres pull in different directions, when the whole muscle is contracted it produces less force than a parallel muscle would
42
How are the Fascicles arranged in a Pennate Muscle?
At a common angle to the tendon
43
How does the angle of fibres in Pennate Muscles effect muscular contraction compared to Parallel Muscles?
The muscle can't contract as far as in a Parallel Muscle, however can produce more tension relative to its size
44
When is a Pennate Muscle Unipennate?
When all the fibres are on the same side of the tendon e.g. the extensor digitorum
45
When is a Pennate Muscle Bipennate?
When it has fibres both sides of a tendon e.g. the rectus femoris
46
When is a Pennate muscle Multipennate?
When the tendon branches within the muscle e.g. the deltoid
47
How does the muscle contraction take place?
ATP on the myosin head allows myosin to attach to actin forming a cross bridge
Then the myosin pivots and bends which pulls actin over the myosin
This allows muscle to shorten without actually shortening the muscle fibres
48
What is the role of Calcium in muscle contraction?
Calcium causes the molecules blocking the binding site on Actin to be moved, allowing the Myosin to bind
49
What is the role of ATP in muscle contraction?
ATP provides the energy for the contraction
50
Which molecules block the binding site on Actin?
Troponin & Tropomyosin
51
What are the 3 types of muscle fibre?
```
Type 1 (Slow Twitch)
Type 2a (Fast Twitch)
Type 2b (Fast Twitch)
```
52
In what manner do slow twitch fibres contract?
Smoothly and gradually
53
How long does it take slow twitch fibres to reach full contraction?
40-50ms
54
Do slow twitch fibres have a high or low capacity to generate force?
Low
55
Do slow twitch fibres generate ATP slowly or quickly?
Slowly
56
Which system do slow twitch fibres use to produce ATP?
Aerobic
57
How is the supply of capillaries in slow twitch fibre?
Good, to be able to supply enough oxygen for producing ATP aerobically
58
What protein do slow twitch fibres contain to make them very good at extracting oxygen from blood, and also gives them their red colour?
Myoglobin
59
Why do slow twitch fibres have lots of mitochondria?
Because this is the only place ATP can be generated aerobically
60
Why are slow twitch fibres good fat burners?
Because fat can only be used to create ATP in the presence of oxygen
61
What are waste products of aerobic ATP production in slow twitch fibres and why does this make them resistant to fatigue?
Water, Heat & CO2, these are dealt with easily and don't inhibit and metabolic processes
62
Do slow twitch fibres need a large stimulus to contract?
No
63
What kind of activity recruits type 1 fibres?
Low to moderate intensity endurance type activities
64
What is the difference in the type of metabolism used in Type 2a and Type 2b fibres?
Type 2a use a mixture of aerobic and anaerobic and are referred to as fast oxidative glycolytic fibres
Type 2b use anaerobic only, and are referred to as fast glycolytic fibres
65
How do Type 2a fibres adapt to training?
The type of metabolism they use will improve depending on how they are trained. Endurance training will improve their aerobic capacity whereas high intensity training will improve anaerobic capacity
66
When are Type 2 fibres recruited?
During high intensity short duration activities
67
Which systems can Type 2 fibres use to create ATP?
Phosocreatine (PCr) & Lactic Acid systems
68
Do type 2 fibres need a large stimulus to contract?
Yes
69
How quickly do type 2 fibres reach full contraction?
About 5ms, this generates considerable power due to the added speed of contraction
70
Do Type 2 fibres generate ATP slowly or quickly?
Quickly
71
Why are Type 2 fibres useful for high intensity work?
Because they don't need Oxygen to create ATP therefore they can produce ATP at near maximal heart rates
72
How do Type 2 fibres create higher tension compared to Type 1
They are thicker and contain more Actin & Myosin
73
How many Mitochondria do Type 2 fibres have?
None
74
Why do Type 2 muscles fatigue easily at high work rates?
Because using glucose as an energy source anaerobically produces Lactic Acid, which prevents further production of ATP until it is removed
75
Why would less fit people tire more easily even at lower work rates?
Because of the inefficiency to generate ATP aerobically Type 2 fibres get recruited even at lower work rates
76
In what order are muscle fibres preferentially recruited?
Type 1 -> Type 2a -> Type 2b
77
What happens when the cross bridges are damages at high workloads?
The muscle adapts and creates more myosin and actin for the muscle, this is Hypertrophy
78
Why can Type 2b fibres turn to Type 2a fibres even in anaerobic training?
Because paying back the oxygen debt to replenish energy stores at rest has an aerobic element to it
79
What is Hyperplasia theory?
The thought that instead of the fibres growing in size (Hypertrophy), they split to make more fibres
No conclusive evidence
80
What are Dense Connective Tissue?
They are a smooth, white tissue which massive tensile strength in one direction, formed almost entirely of collagen with also a small number of elastic fibres
81
What is a Tendon?
A connective tissue that joins the epimysium of a muscle to bone
82
What is a Ligament?
A connective tissue that joins bone to bone
83
How much elasticity do Ligaments have?
Only about 6% whilst being able to return to original length
84
Do Ligaments have much in the way of blood supply?
No
85
What is the role of Articular Cartilage & Ligaments?
They contain nerve endings that sense positional change, these proprioceptors signal that a joint is under pressure and cause muscles to be recruited that can change that
86
What are the properties of Cartilage?
```
is dense
is tough
is fibrous
withstands compression
can be worn or torn
is very similar to plastic and is very durable
does NOT have a blood supply
has limited ability to repair itself
is dependent on regular physical activity for health
```
87
What are the properties of Hyaline (Articular) Cartilage?
is tough, smooth and thin
is bluey white in colour
is found covering bone ends to form joints
becomes slippery when lubricated with synovial fluid thus reducing friction and allowing optimal joint movement.
88
What are the properties of Elastic Cartilage?
has a structure similar to hyaline cartilage
has more fibres than hyaline cartilage
has most of its fibres made up of elastin as opposed to collagen
has the ability to spring back into shape immediately due to the properties of elastin
can be found in the ear, the walls of the Eustachian tube (the tube that runs from the middle ear to the pharynx) and the epiglottis, all places that require maintenance of a specific shape.
89
What is the role of Fibrocartilage?
It is a thicker and stronger cartilage that acts as a shock absorber in joints e.g. Meniscus in the knee
90
Why are the core muscles important to stability?
Because unlike the thorax, the abdominal wall has no skeletal reinforcement
91
What role do the muscles involved in core stability play aside from stability?
Protect the abdominal organs and lumbar spine
92
Why are exercises such as stomach crunches ineffective to improving core stability?
Because the main muscles in core stability don't bring about large movements, their job is mainly to restrict not to move
93
What problems can a weak core lead to?
Poor posture, incorrect spinal alignment, abdominal distension and spinal injuries
94
What is the location and role of the Transversus Abdominus?
It is the innermost muscle of the stomach wall, wrapping around like a corset
It protects the back and flattens the stomach
95
Where is the origin of the Transversus Abominus?
Thoracolumbar Facia
96
Which three bones fused together make up each side of the Pelvic Girdle?
The Ilium, Ischium & Pubic Bone
97
What is the main action of the Levator Ani pelvic floor muscle?
Supports pelvic viscera/organs and provides sphincter like action in the anal canal and vagina
98
Where is the Origin of the Levator Ani pelvic floor muscle?
Pubis & Ischium
99
Where is the Insertion of the Levator Ani pelvic floor muscle?
Coccyx
100
What is the main action of the Superficial Transverses Perinea pelvic floor muscle?
Supports pelvic viscera/organs
101
Where is the Origin of the Superficial Transverses Perinea pelvic floor muscle?
Ischium
102
Where is the Insertion of the Superficial Transverses Perinea pelvic floor muscle?
Central Tendon
103
What is the main action of the Bulbospongiosus?
Males: Assists in emptying ureathra
Females: Contracts vagina
104
Where is the Origin of the Bulbospongiosus?
Central Tendon
105
Where is the Insertion of the Bulbospongiosus?
Males: Penis
Females: Root of clitoris
106
What is the main action of the Ischiocavernosus?
Assists function of Bulbospongiosus
107
Where is the Origin of the Ischiocavernosus?
Ischium
108
Where is the Insertion of the Ischiocavernosus?
Pubic Arch
109
Which are the Deep/Local Muscles of the Core?
```
Transversus Abdominis
Multifidus
Internal Oblique
Quadratus Lumborum
Pelvic Floor Muscles
Diaphragm
```
110
What kind of support does the Transversus Abdominis provide?
Anterior
111
What kind of support does the Multifidus provide?
Posterior
112
What kind of support does the Internal Oblique provide?
Lateral
113
What kind of support does the Pelvic Floor Muscles provide?
Inferior
114
What kind of support does the Diaphragm provide?
Superior
115
Which are the Superficial/Global Muscles?
```
Rectus Abdominis
Erector Spinae (iliocostalis, longissimus, spinalis)
External Oblique
```
116
What causes women to have greater pelvic instability?
A larger Q angle due to a wider child bearing pelvis
117
What are often seen hip dysfunctions in women?
IT band syndrome, femoral anteversion and pronation at the knee
118
What common lower extremity dysfunctions are often seen in women?
Over pronation of foot
| Anterior pelvic tilt coupled with lengthening of abdominal wall (often a result of child bearing)
119
What injuries are female runners more prone to?
Knee, calf and ankle injuries
120
What environmental factors often affect female posture?
Added weight from long hair
Kyphotic posture, sometimes from spinal flexion trying to hide developing breasts due to self consciousness
High heeled shoes
121
What muscular changes can be caused by wearing high heeled shoes?
Shortening of the Soleus & Gastrocnemius
Hyperextension of the knee causing tightening in lumbar erectors & hip flexors
Posterior neck muscles shorten to lift head as a reaction to body being tipped forward
122
Do females generally have a higher or lower percentage of fat than males?
Higher
123
What are problems associated with females being more flexible than males?
Can cause joint pain, common around sacroiliac and knee joints
124
Why can pregnancy cause more flexibility problems?
The hormone Relaxin loosens joints and connective tissues in preparation for birth
125
How many thick, strong, short ligaments are there in each hip joint?
7
