1
Q
muscle can only (push/pull)
A
pull
2
Q
Describe the skeleton + it is divided into what?
A
Muscles function by pulling against bones that rotate about joints and transmit force through the skin to the environment.
The skeleton can be divided into the axial skeleton and the appendicular skeleton.
3
Q
what are joints?
A
junction of bones
3
Q
What is in the appendicular skeleton?
A
- Shoulder (Pectoral ) Girdle
- Left & right humerus
- Radius, ulna
- Carpals, metacarpals, & - phalanges
- Pelvic girdle
- Left & right femur
- Patella
- Tibia, fibula
- Tarsals, metatarsals, & phalanges
3
Q
What is in the axial skeleton?
A
- Cranium (skull)
- Vertebral column
- Ribs
- Sternum
4
Q
definition of anatomy vs Biomechanics
A
Anatomy
The study of components that make up the musculoskeletal “machine.”
Biomechanics
The mechanisms through which the musculoskeletal components interact to create movement.
5
Q
3 type of joint
A
fibrous, cartilaginous, synovial
6
Q
Describe the Fibrous, cartilagenous and Synovial joints
A
Fibrous: no movement, example: sutures of the skull
Cartilagenous: very little movement, intervertebral disks
synovial joints: allow considerable movement: leg or knee extension
7
Q
What definition is used universally?
A
Anatomical because alternate can cause confusion between the origin and insertion points comparing 2 or more exercises
8
Q
Difference between Anatomical and Alternate definition for origin and insertion points
A
Anatomical:
- point of origin: the proximal muscle structure
- point of insertion: distal muscle attachment
Alternate:
Origin: the stationary structure to which the muscle is attached
Insertion: the mobile structure to which the muscle is attached
9
Q
Describe agonist, antagonist and synergist muscles
A
Agonist
The muscle most directly involved in bringing about a movement; also called the prime mover.
Antagonist
A muscle that can slow down or stop the movement.
Synergist
A muscle that assists indirectly in a movement
10
Q
What do body movements directly involved in sports and exercise primarly act through?
A
through bony levers of skeleton
11
Q
Definition of lever
A
a lever is a rigid or semi-rigid body that pivots around a fulcrum
when force is applied on the lever, there is a rotational effect around the fulcrum that exerts a force on the object to overcome a resistance to movement.
12
Q
FA =
MAF=
FR =
MRF =
Moment arm is also called ?
A
FA = force applied to the lever.
MAF = moment arm of the applied force.
FR = force resisting the lever’s rotation.
MRF = moment arm of the resistive force.
Moment arm is also called the force, lever, or torque arm
13
Q
Definition of Torque
A
is a rotatory force
also called: moment
degree to which a force tends to rotate around a fulcrum
equation: magnitude of force x length of moment arm
T = F x d_perpendicular
14
Q
which moment arm is an advantage
A
when moment arm > 1
15
Q
when does moment arm is a disadvantage
A
MA < 1
16
Q
which moment arm favors low strength and high velocity
A
MA < 1
17
Q
which moment arm favours high strength and low velocity
A
MA > 1
18
Q
when does MA < 1
A
when FR < Fa
19
Q
when does MA > 1
A
when Fa< Fr
20
Q
What are the lever classes?
A
1st class Lever : RF-F-MF = MF-F-RF
2nd class lever: MF-RF-F = F-RF-MF
3rd Class lever: RF-MF-F = F-MF-RF
21
Q
isometric exertion or constant-speed joint rotation is which class of lever
A
1st
22
Q
where would the MF be placed?
A
at insertion. which then will determine what class lever
23
which class of lever occurs when the body is stationary or moving upward at a constant velocity
2nd
24
exemple of 2nd class lever
calf raise
25
exemple of 1st class lever
elbow extension against resistance
26
exemple of 3rd class lever
elbow flexion against resistance
27
which class lever occurs when the arm is stationary or moving upward at a constant velocity
3rd class lever
28
role of patella in mechanic of the knee
The patella increases the mechanical advantage of the quadriceps muscle group by maintaining the quadriceps tendon’s distance from the knee’s axis of rotation.
29
What happens as the weight is lifted ?
The moment arm changes, so the torque changes from the elbow to the weight
30
most skeletal muscle operate at a considerable mechanical (advantage/disadvantage)
disadvantage
31
the primary lever orientation in the human is
3rd class
32
human are built more for (speed/strenght) than (speed/strenght)
speed than strength
33
during sports and other physical activities, forces in the muscles and tendons are much (higher/lower) than those exerted by the hands or feet on external objects or the ground.
higher
34
tendon insertion farther from the joint center result in
ability to lift heavier, has larger moment arm = create greater torque but less rotation per unit of muscle contraction so slower movement speed
35
bench press in anatomical plane?
Transverse
36
strength is associate with
often associated with slow speed of movement, ability to exert force at low speed
although: preferred definition would be the ability to exert force at any speed
37
What is power?
Rate of performing work
= work/Time, where work = Force x Distance
= Force x Velocity, where velocity is Distance/Time
it is the mathematical product of force and velocity at whatever speed
*often associated with fast speeds
ability to exert force at high speeds
38
What are the biomechanical factors in Human strength? (9)
- Neural Control
- Muscle Cross-Sectional Area
- Arrangement of muscle fibers
- Muscle length
- Joint angle
- Muscle contraction velocity
- Joint angular velocity
- Strength-to-mass ratio
- Body size
39
muscle force is greater when
more motor units are involved in a contraction,
the motor units are greater isze, or
the rate of firing is faster.
40
the force a muscle can exert is related to what__
cross-sectional area rather than to its volume
so if we have same cross sectional area for 2 different muscles: will generate the same force.
41
what is a pennate muscle
a muscle with fibers that align obliquely with the tendon, creating a featherlike arrangement.
42
what is the angle of pennation
is the angle between the muscle fibers and an imaginary line between the muscle’s origin & insertion
43
what is most often the pinnation angle
< or equal to 15º
44
what happen with force generation if a muscle have CSA is constant but have an increase in pinnation
allows a muscle to generate a greater amount of force than nonpennate muscle.
**any factor that affects its angle of pennation will influence both strength and velocity of shortening.
especially knowing that in pennation, sarcomeres are places parallel: increasing force production.
45
what happen with velocity if a muscle have CSA remaining the same but have an increase in pennation
results in a lower maximal shortening velocity than nonpennate muscle
46
characteristics of Pennate muscle
they have muscle fibers in parallel which produces more Force
- lower velocity
- smaller Range of Motion
47
characteristics of Non-pennate muscle (ex. Longitunidal)
smaller force, higher velocity
Higher Range of motion
48
to confirm with teacher: more sarcomeres in parallel how come would generate greater force production in a higher angle of pennation
yes only parallel not in series
49
when does a muscle generate the greatest amount of force
when it is a its resting length.
when muscle is stretched beyond, there is a fewer interactions between Myosin and Actin, so not a lot of force production
explained by the "sliding filament theory"
50
the amount of torque that can be exerted about a given body joint varies throughout a joint's ROM and depends on:
the force versus muscle length relationship,
the variation in leverage attributable to the dynamic geometry of the muscles, tendons (which means: Leverage: how effectively a muscle force can rotate a bone or joint — basically, how much “mechanical advantage” it has.
Dynamic geometry: the positions and angles of muscles, tendons, and bones aren’t fixed — they change as you move.
Variation in leverage: because those positions change, the leverage (the ability to produce torque or rotational force) also changes.), & internal joint structures,
type of exercise,
the body joint in question,
the muscles used at that joint, and
the speed of contraction.
51
the force capability of muscle (decrease/increase) as the velocity of contraction (decrease/increase)
decrease, increase
52
as velocity of movement (decrease/increase), the max force a muscle can produce concentrically (decrease/increase)
increase, decrease
53
relationship btw force velocity is linear or non-linear
NOT linear
54
the decline of force-velocity is steepest when speed is (increase/decrease) from
increase from slow to moderate
55
what is the max power a muscle
around 1/3 Vmax
56
When is the slope the less steepest?
when speed is increasing from moderate to fast
57
a well-designed strength power training program will shift the force-velocity to the (right/left) and the power curve (downward/upward)
right, upward
58
Muscle Torque varies ...according to what?
joint angular velocity according to the type of muscular action (eccentric, concentric, isokinetic)
59
What do eccentric muscle action generate the greatest force?
because of titin (structural protein)
Titin was identified as structural protein whose force is increased in eccentric muscle action but not in passive muscle
*When lengthening a muscle, this molecule will provide tension, that is why during the eccentric muscle action there is more tension in the muscle
60
during isokinetic concentric exercise torque capability (increase/decline) as angular velocity (increase/decline)
decline, increase
61
during which type of angular velocity torque capability declines as angular velocity increases
isokinetic concentric
62
during eccentric exercise maximal torque capability (increase/decline) until about 90% after which it (increase/decline) gradually
increase, decline
63
during which angular velocity maximal torque capability increases until about 90o/s, after which it declines gradually.
eccentric
64
place angular velocity in order of muscle force
eccentric > isometric > concentric
65
strength-to-mass ration reflect what
athlete ability to accelerate their body
66
In what sports, is the strength-to-mass ratio important?
Sprinting, jumping, weight classification.
67
What happens to a sprinter’s ability to accelerate if he or she increases body mass and force capability by 15% and 10%, respectively?
strength-to-mass ratio and thus, the athlete's ability to accelerate reduces
68
Which of the following wrestler’s has a decided advantage in strength?
Wrestler A: higher strength, body weight = 200 lb.
69
Is the strength-to-mass ratio of larger athletes higher or lower than that of smaller athletes?
no, smaller athlete will have a higher strength to mass ratio because larger athlete would increase volume but not cross-sectional area (related to strength)
70
as body size (increase/decrease) body mass (increase/decrease) rapidly than the does muscle strength
increase, increase
71
a muscle contractile force is fairly proportional to its
csa - related to the square (2nd power ) of linear body dimensions
72
muscle mass is proportional to its
volume- related to the cube of linear dimensions (3rd power)
73
What are common sources of Resistance?
- Gravity
- Inertia
- Friction
- Fluid Resistance
- Elasticity
74
Define Gravity
Fg = m x ag
Fg = force due to gravity = object’s weight (N).
m = mass of an object (kg).
ag = local acceleration due to gravity.
Gravitational Force
on an object always acts downwards.
75
What direction is the moment arm of weight always in?
moment arm of a weight is always horizontal
76
during a free weight exercise, when the weight is horizontally closer to the joint, it exerts (more/less) resistive torque
less
77
Free weight (dumbbell or barbell) is an example of what?
constant resistance exercise because of the same weight stays the same during the whole exercise.
78
Describe weight stack machines
The machines provide increased control over the direction and pattern of resistance.
Constant and variable resistance exercise machines.
79
How is it possible to have a variable resistance exercise machine?
the resistance varies to match your muscle's ability
The cam reduces resistance where you’re weaker and increases it where you’re stronger.
This is designed to match the machine’s resistance profile to your strength curve
80
Does moment arm varies in cam-base exercise machines?
in cam-based weight stack machines , the moment arm of the weight stack varies during the exercise movement.
it goes from the cam pivot point (elipse) to the weight stack machine
81
What is special about cam-like exercise machines?
The axis of rotation is the elipse
*if variable resistance exercise that has this cam structure, the axis of rotation for the stack is on the cam*
For the muscle, it will be jointed (elbow joint, for example)
82
What is Inertia?
- The tendency for a body to resist acceleration.
- The tendency of a body at rest to remain at rest or of a body in motion to stay in motion in a straight line unless disturbed by an external force.
- Acceleration and deceleration are fundamental characteristics of virtually every natural movement.
Inertial force can act in any direction
83
84
what happen in beggining of a barbell curl
the bar is accelerated from a zero velocity to an upward velocity.
85
what happen near the top of a barbell curl
there is some deceleration to bring the bar’s velocity back to zero.
86
what happen early in the ROM of a barbell curl
the agonist muscles receive resistance in excess of the bar weight
87
what happen toward the end of the ROM of a barbell curl
the agonist muscles receive resistance less than the bar weight.
88
What are forms of Acceleration training?
- Explosive exercises (Power Clean
Power Snatch
Push Press
Push jerk
Clean & Jerk
High Pull)
- Bracketing Technique:
(A sport movement is performed with less than normal & greater than normal resistance.)
89
Define Friction
is the resistive force encountered when one attempts to move an object while it is pressed against another object.
FR = k x FN
FR = resistive force.
k = coefficient of friction for the 2 substances in contact (coefficient of static or moving friction).
FN = normal force, which presses the objects against each other.
90
why is it harder to push a weighted sled initially at rest?
It takes more force to initiate the sled’s movement than to maintain its initial movement because the coefficient of static friction is always > than the coefficient of sliding friction.
91
What are 2 types of resistance to overcome when pushing a sled?
- Must overcome the resistance due to the sled’s inertia:
Directly proportional to the sled’s mass & acceleration.
- Must also overcome the resistance due to the friction between the sled’s runners & the ground:
Proportional to the friction coefficient between the contact surfaces & the net force pressing against the sled.
92
What are fluid-resistance exercises?
Hydraulic (liquid) & pneumatic (gas) exercise machines.
93
What is the formula for fluid-resistance?
FR = k x v
FR =resistive force.
k = constant that reflects the:
physical characteristics of the cylinder & piston,
viscosity of the fluid, &
number, size, & shape of the orifices.
v = piston velocity relative to the cylinder.
94
Characteristics of fluid-resistance exercise machine
- Most often use cylinders in which a piston forces fluid through an orifice (opening).
- How can the resistive force be increased using this machine?
- Allow rapid acceleration early in the exercise movement.
- Allow little acceleration after higher speeds are achieved.
- Cannot perform isokinetic exercise on these machines.
- Do not generally provide an eccentric exercise phase, although machines with an internal pump do.
95
Describe Elasticity
FR = k * x
FR =resistive force.
k= constant that reflects the physical characteristics of the elastic component.
x = distance that the elastic component is stretched beyond its resting length.
**the greater the distance the greater the force**
96
What happens when stretching an elastic band?
Stretching an Elastic Band
- The more that the band is stretched, the greater the resistance.
- The exercise movement begins with low resistance & ends with high resistance
97
why is the adjustability of the band’s resistance limited?
limited by the number of elastic components available to provide resistance to a movement.
98
why is the stretching band mechanism unusual compare to human movements?
So when we begin to stretch here is not a lot of resistance , the resistance is increased when the band is stretched to its maximum which is opppsite to what we see in human movements where: at the beginning: there is a lot more resistance and that slowly decreases at the end of range of motion.
Another example for elastic resistive exercises: is that when someone jumps vertically high , greatest resistance is when the jumper is high in the air to mainly pull the jumper back to the ground and to increase the speed of when he hits the ground on landing
99
what is surface drag
Results from the friction of a fluid passing along the surface of an object.
100
what is form drag
Results from the way in which a fluid presses against the front or rear of an object moving through it.
101
fluid-resistance exercise machine allow what
Allow rapid acceleration early in the exercise movement.
Allow little acceleration after higher speeds are achieved.
102
which type of exercise machine Do not generally provide an eccentric exercise phase, although machines with an internal pump do.
fluid-resisted exercise machine
103
which type of exercise machine cannot perform isokinetic exercise
fluid-resisted exercise machine
104
during 3rd class lever muscle is at advantage or disadvantage and why
This is a disadvantage because a larger muscular force is required to move the resistance.
MM < MR, FM > FR .
105
during 2nd class lever muscle are at advantage or disadvantage
This is an advantage because a small muscular force is required to move a person’s body weight.because
MM > MR, FM < FR .
106
1st class lever muscle work at an advantage or disadvantage
disadvantage
107
Describe "intra-abdominal pressure and lifting belts"
when the diaphragm and deep muscles of torso contract, pressure is generated within the abdominal cavity.
Because the abdomen is filled with fluid; IT IS INCOMPRESSIBLE and aids in supporting the vertebral column during resistance training which may significantly reduce forces required by the erector spinae muscles to perform an exercise.
Advantage of Valsalva maneuver: increases rigidity of torso , making it easier to lift weights, so this VALSALVA MANEUVER is not necessary to increase intra abdominal pressure BECAUSE ALREADY INCREAES RIGIDITY OF TORSO*** Although, can raise blood pressure and more difficult for blood to return to the heart.
Safer option: abdomen and diaphragm can contract without glottis being closed
Weightlifting belts: increase intra abdo pressure, improves safety.
But if someone is used to wearing weight belts and takes it off, abdo muscles may not be increasing intra abdominal pressure to significantly reduce the erector spinae muscle forces.
108
what are the recommendations for wearing weight-lifting belts?"
- Weight belts not needed for exercises that do not affect lower back
- For exercises directly stressing the back an individual should refrain from wearing a belt during lighter loads sets but may wear one for near max or max sets. beltless sets allow the deep abodminal muscles to generate intra abdominal pressure to receive a training stimulus without compressive forces on the disks
- Individual may reasonably choose to never wear lifting belts if they build up strength of back muscles that generate intra abdo pressure in gradual and systematic way.
109
what is skeleton musculature?
A system of muscles enables the skeleton to move.
110
Know the major primer movers
EXCI 352
flashcards
Decks in class (15)
# Cards
-
CHAP 2112
-
Need analysis64
-
periodization140
-
principle of test selection and administration59
-
administration, scoring and interpretation of selected test75
-
warm-up and flexibility81
-
exercise technique for free weight and machine training50
-
PLYOMETRIC TRAINING99
-
SPEED & AGILITY177
-
ANAEROBIC TRAINING57
-
ENDOCRINE RESPONSES TO RESISTANCE EXERCISE73
-
PROGRAMME DESIGN FOR RESISTANCE TRAINING92
-
AEROBIC ENDURANCE TRAINING114
-
PERFORMANCE-ENHANCING SUBSTANCE155
-
Regulation of skeletal muscle mss41
