Chapter 5 Human Movement Science Final

Question 1

-the study of applying laws of mechanics and physics to determine how forces affect human movement and to better predict performance in athletic events. -The science concerned with the internal and external forces acting on the human body and the effects produced by these forces.

Answer 1

Biomechanics

Question 2

Ipsilateral

Answer 2

Positioned on the same side of the body.

Question 3

The Sagittal Plane divides the body into what halfs?

What plane does its axis occur on?

What sort of exercises occur on this plane?

Answer 3

• An imaginary bisector that divides the body into left and right halves.
• Sagittal plane movement occurs around Coronal Axis.
• Examples of predominately Sagittal Plane Movements: *bicep curls, triceps pushdowns, squats, front lunges, calf raises, walking, running, vertical jump, climbing stairs, shooting a basketball.

Question 4

The Frontal Plane divides the body into what halfs?

What plane does its axis occur on?

What sort of exercises occur on it?

Answer 4

• An imaginary bisector that divides the body into front and back halves.
• Occurs around an anterior-posterior axis
• Examples: side lateral raises, side lunges, side shuffling

Question 5

Transverse Plane divides the body into what halfs?

What plane does its axis occur on?

What sort of exercises occur on this plane?

Answer 5

• An imaginary bisector that divides the body into top and bottom halves.
• Occurs around a longitudinal or vertical axis
• Examples: cable trunk rotations, dumbbell chest fly, throwing a ball, throwing a frisbee, and swinging a bat.

Question 6

What are the three primary muscle actions?

Answer 6

1. Isotonic (eccentric and concentric) 2. Isometric 3. Isokinetic

Question 7

Isotonic Muscle Action/Contraction

Answer 7

-Constant muscle tension -Force is produced, muscle tension develops, and movement occurs through a given range of motion. -Two types: Eccentric and Concentric

Question 8

Eccentric Muscle Action

What happens to the length of the muscle?

How is the contractile force related to the resistive force in intensity and direction?

What is it synnonymous with?

What name is it known as?

Give an example in relation to a squat.

Answer 8

• Occurs when a muscle develops tension while lengthening.
• Contractile force is less than the resistive force
• Moves in the same direction as the resistance
• Synonymous with deceleration or reducing force (like bench press, the weight of the bar must be decelerated and then stabilized to be properly accelerated.
• Examples: landing from a jump, lowering weight during resistance exercise, lowering phase of a squat, all forms of resistance training (walking on treadmill, bench pressing)
• Known as “a negative” - work is actually being done one the muscle because forces move the muscle, rather than the muscle doing the work (or the muscle moving the forces)
• It “returns to resting length” not actually increasing length as though being stretched.

Question 9

Concentric Muscle Action

How is the contractile force related to the resistive force in intensity and direction?

What happens to the length of the muscle?

What is it synonymous with?

Give an example in relation to squats.

Answer 9

• When a muscle is exerting force greater than the resistive force,
• Moves in the opposite direction of resistive force
• Resulting in shortening of the muscle and visible joint movement.
• Synonymous with acceleration
• Examples: jumping upward, and during the lifting phase of a squat.

Question 10

Isometric Muscle Action

Answer 10

-When a muscle is exerting force equal to the force being placed on it leading to no visible change in the muscle length. -Example: when an individual pauses during a resistance training exercise in between the lifting and lowering phases.

Question 11

Isokinetic Muscle Action

Answer 11

• When a muscle shortens at a constant speed over the full range of motion. Resistance varies.
• The tension in the muscle is at its maximum throughout the whole range of motion.
• Believed to improve strength, endurance, and neuromuscular efficiency.
• requires use of expensive, sophisticated equipment that measures the a out of force generated by the muscles and adjusts the resistance (load) so that no matter how much the muscle tension is produced, movement remains constant (that harder you push, the more resistance/heavier you/it feel/s)

Question 12

Length-Tension Relationship

What is optimal

and three examples of less optimal?

Answer 12

-The resting length of a muscle and the tension of the muscle can produce at this resting length.

*There is an optimal muscle length when actin and myosin filaments have the greatest degree of overlap = potential for maximal force production of that muscle.

*Lengthening too much during contraction reduces overlap thus reduces force production.

*Shortening the muscle too much creates maximal overlap and allows no further movement to occur between filaments, reducing force output.

*If muscle lengths are altered (ex. Misaligned joints = bad posture), then they will not generate the needed force to allow for efficient movement.

Question 13

Force-Velocity Curve

Answer 13

-The relationship of muscle’s ability to produce tension at differing shortening velocities.

*Velocity of concentric muscle increases, ability to produce force decreases (results thought to be bc overlapping filament may interfere with its ability to form cross bridges with myosin)

*Velocity of eccentric muscle action increases, the ability to develop force increases (results thought to be b/c elastic component of the connective tissue surrounding and within the muscle).

Question 14

Force-Couple

Under what circumstances can proper force-couple relationships occur?

Answer 14

• Synergistic action of muscles (muscle groups moving together) to produce movement around a joint.
• Provide divergent pulls on the bones or bones the connect with *Due to the different attachment sites that each muscle has, creates pulls at a different angles, and creates a different force on the joint.
• Motion dependent on structure of joint and the collective pull of each muscle involved.
• Proper force-couple relationships can only occur if the muscles are at the right length-tension relationships and the joints have proper arthrokinematics (joint motion), two allowing proper sensorimotor integration and ultimately proper and efficient movement.

Question 15

Give examples of Force-Couples for:

Trunk rotation

Upward rotation of scapula

Hip and knee extension during stair climbing

Plantar flexion

Shoulder Abduction

Answer 15

1. Muscles: Internal and External Obliques; Movement: Trunk Rotation
2. Muscles: Upper trapezius and the lower portion of the serratus anterior; Movement: upward rotation of scapula
3. Muscles: Gluteus Maximus, quadriceps, and calf muscles; Movement: produce hip and knee extension during walking, running, stair climbing, etc.
4. Muscles: Gastrocnemius, peroneus longus, and tibialis posterior Movement: Performing plantarflexion at the foot and ankle complex
5. Muscles: Deltoid and Rotator Cuff Movement: performing shoulder abduction

Question 16

Describe the basic principle of levers in regard to muscle motion in the Human Movement System (HMS).

Answer 16

• A lever consists of a rigid “bar” that pivots around a stationary fulcrum (pivot point).
• In the HMS:

*Joint axis = fulcrum

*Bones = levers

*Muscles = effort (create motion) (muscles pull on bones; they cannot actively push)

*Resistance = weight of the body part, or the weight of an object (barbells and Dumbbells)

Question 17

Give examples of first, second, and third class levers in the HMS.

What force is in the middle for each lever?

Which do most limbs opperate as?

Answer 17

1st Class -Fulcrum in middle like a seesaw

(nodding head where the top of spinal column is fulcrum).

2nd Class -Resistance in the middle with fulcrum and the muslce’s effort on either side, like a load in a wheelbarrow (because when you lift a wheelbarrow the effort is on the handles and the folcrum is on the opposite end with gravity in the middle).

(push-up or calf raise - where the ball of foot is fulcrum, body weight is resistance, effort applied by calf musculature).

3rd Class-Effort in the middle between resistance and the fulcrum -The effort always travels a shorter distance and must be greater than resistance,

• (forearm- fulcrum is elbow, the effort is applied by the bicep muscle which attaches slightly outside of the elbow, the load is in the hand like dumbbell when performing bicep curl)*.
• Most limbs in human body operate as third class levers

Question 18

Rotary Motion

Answer 18

-Movement of levers (bones) that rotate around the axis (joints).

Question 19

What is Torque?

What increases or decreases torque?

Answer 19

• A force that produces rotation (the turning effect of a joint in a rotary motion).
• Common unit of torque is the newton-meter or Nm.
• Determined by distance that the weight is from the center of the joint and the muscle’s attachment and the line of pull (direction tension is being applied through tendon) is from the joint will determine efficiency with which muscles manipulate the movement. *the closer the weight is to the point of rotation (joint), the less torque it creates. *the farther the weight is from the point of rotation, the more torque it creates.

Question 20

Motor Behavior

Answer 20

• Motor response to internal and external environmental stimuli.
• The study of motor behavior examines the manner by which the nervous, skeletal, and muscular systems interact to produce movement using sensory information from internal and external environments.
• A collective study of motor control, motor learning, and motor development.

Question 21

Motor Control

Answer 21

• How the central nervous system integrates internal and external sensory information with previous experiences to produce a motor response.
• The study of posture and movements with the involved structures and mechanisms used by the CNS to assimilate and integrate sensory information with previous experiences.
• Concerned with what CNS structures are involved with motor behavior to produce movement.

Question 22

Motor Learning

Answer 22

• Integration of motor control processes through practice and experience, leading to the relatively permanent change in the capacity to produce skilled movements.
• Muscle Memory?

Question 23

Motor Development

Answer 23

-The change in motor skill behavior over time throughout the lifespan.

Question 24

Muscle Synergies

Answer 24

• Groups of muscles that are recruited by the central nervous system to provide movement.
• Simplifies movement by allowing muscles and joints to operate as a functional unit.
• Through practice of proper movement patterns (proper exercise technique), these synergies become more fluent and automated (muscle memory?).

Question 25

What is…

• The cumulative sensory input to the CNS from all mechanoreceptors (muscle spindle, Golgi tendon organ, and joint receptors) that provide information about body position, movement, and sensation as it pertains to muscle and joint force.
• Vital source for the CNS to gather info about environment to produce most efficient movement

What alters it?

Answer 25

Proprioception.

-Altered after injury.

Question 26

What is the cooperation of the nervous and muscular system in gathering and interpreting information and executing movement.

Answer 26

Sensorimotor Integration

Question 27

Feedback

Answer 27

-The use sensory information and sensorimotor integration to help the HMS in the development of permanent neural representations of motor patterns/motor learning.

Question 28

• “Sensory feedback”
• The process whereby sensory information is used by the body via length-tension relationships (posture), force-couple relationships, and arthrokinematics to reactively monitor movement and the environment.
• Acts as a guide, steering HMS to the proper force, speed, and amplitude of movement patterns.

Answer 28

Internal Feedback

Question 29

Define External Feedback.

What are the two types?

What makes them more effective?

What should trainers be wary of?

Answer 29

• Information provided by some external source, such as a health and fitness professional, videotape, mirror, or heart rate monitor, to help supplement the internal feedback.
• Two major forms:
  1. Knowledge of Results: used after completion of a movement to help inform a client about the outcome of the performance. “your squats look good.” “could you feel your good form?”
  2. Knowledge of Performance: provides information about the quality of the movement during a exercise. Like noticing their knees were excessively adducting and asking if they felt or looked different.
• Its more effective when getting the client involved so they become more aware of their own sensory/internal feedback.
• Be wary of excessive use, developing a dependency on external feedback instead of awareness of sensory imput.

Question 30

What ultimately dictates movement?

Answer 30

The Nervous System ultimately dictates movement.

Question 31

Why is it very important to use correct technique at all times?

What three things could happen if a client continuously performs chest press exercises while rounding and elevating the shoulders?

What does this ultimately lead to?

Answer 31

Its important to use correct techniques at all times to deliver proper sensory information to the central nervous system.

Not doing so could cause:

• Altered length-tension relationships of muscles (altered muscle length)
• Altered force-couple relationships of muscles (improper muscle recruitment patterns)
• Altered arthrokinematics (improper joint motion)

This ultimately leads to shoulder impingement or other injuries.

Question 32

Internal/External rotation (of limbs) occurs on what plane?

Answer 32

Transverse

Question 33

R/L Rotation (head and trunk) occurs on what plane?

Answer 33

Transverse

Question 34

Horizontal abduction and adduction of the limbs occurs on what plane?

Answer 34

Transverse

Question 35

Radioulnar (forearm) pronation and supination occurs on what plane?

Answer 35

Transverse

Question 36

Abduction/adduction occurs on what plane?

Answer 36

Frontal

Question 37

Lateral flexion occurs on what plane?

Answer 37

Frontal

Question 38

Eversion/inversion occurs on what plane?

Answer 38

Frontal

Question 39

Flexion and extension occur on what plane?

Answer 39

Sagittal