Chapter 5 Flashcards
Biomechanics
The science concerned with the internal & external forces acting on the human body & the effects produced by these forces; “sports biomechanics”
Helps to better predict performance in athletic events
Superior
Positioned above a point of reference
Inferior
Positioned below a point of reference
Proximal
Positioned nearest the center of the body, or point of reference
“The knee is more proximal to the hip than the ankle”
Distal
Positioned farthest from the center of the body or point of referance
Anterior (or Ventral)
On the front of the body
Posterior (or Dorsal)
On the back of the body
“The hamstring complex is located on the posterior aspect of the thigh”
Medial
Positioned near the middle of the body
Lateral
Positioned toward the outside of the body
Contralateral
Positioned on the opposite side of the body
Ipsilateral
Positioned on the same side of the body
What are the 3 dimensions used to describe human movement?
Sagittal; Frontal; Transverse
Anatomic Position
The position of the body erect with the arms at the sides & the palms forward. The anatomic position is of importance in anatomy because it is the position of reference for anatomic nomenclature. Terms like anterior/posterior, lateral etc. apply to the body in this position
Sagittal Plane
An imaginary bisector that divides the body into left & right halves
Flexion/Extension motion; Coronal axis
Biceps curl, Triceps pushdown, Squat, Front lunge, Cal raise, Walking, Running, Vertical jumping & Climbing stairs
Flexion
A bending movement in which the relative angle between 2 adjacent segments decreases
Extension
A straightening movement in which the relative angle between 2 adjacent segments increases
Hyperextension
Extension of a joint beyond the normal limit or range of motion
Frontal Plane
An imaginary bisector that divides the body into front & back halves
Adduction/Abduction, Lateral Flexion, Eversion/Inversion; Anterior-posterior axis
Side lateral raise, Side lunge, Side shuffle
Abduction
A movement in the frontal plane away from the midline of the body; protraction
Adduction
A movement in the frontal plane back toward the midline of the body; retraction
Transverse Plane
An imaginary bisector that divides the body into top & bottom halves
Internal rotation, External rotation, left/right rotation, Horizontal adduction, Horizontal abduction
Longitudinal axis
Trunk rotation, Throwing, Golfing, Swinging a bat
Internal Rotation
Rotation of a joint toward the middle of the body
External Rotation
Rotation of a joint away from the middle of the body
Horizontal Abduction
Movement of the arm or thigh in the transverse plane from an anterior position to a lateral position
Horizontal Adduction
Movement of the arm or thigh in the transverse plane from a lateral position to an anterior position
Scapular Retraction
Adduction of scapula; shoulder blades move toward the midline
Scapular Protraction
Abduction of scapula; shoulder blades move away from the midline
Scapular Depression
Downward (inferior) motion of the scapula
What are the 3 primary types of muscle actions?
- Isotonic - constant muscle tension
- Isometric - constant muscle length
- Isokinetic - constant velocity of motion
What do the following prefixes mean? ISO; TONIC; METRIC; KINETIC
ISO - same or equal; eccentric & concentric
TONIC - tension
METRIC - length
KINETIC - motion
What happens in an ISOTONIC muscle contraction
Force is produced, muscle tension is developed & movement occurs through a given range of motion
Eccentric Muscle Action
An eccentric muscle action occurs when a muscle develops tension while lengthening
Synonymous with deceleration
Concentric Muscle Action
When a muscle is exerting force greater than the resistive force, resulting in shortening of the muscle
Synonymous with acceleration
Muscle Action Spectrum
Isotonic- force is produced, muscle tension is developed, and movement occurs through a given range of motion
Eccentric - Moving in the same direction as the resistance; decelerates or reduces force
Concentric - moving in opposite direction of force; accelerates or produces force
Isometric
Isokinetic
Isometric Muscle Action
When a muscle is exerting force equal to the force being placed on it leading to no visible change in the muscle length
No visible movement with or against resistance
Dynamically stabilizes forces
Isokinetic Muscle Action
When a muscle shortens at a constant speed over the full range of motion
The speed of movement is fixed, and resistance varies with the force exerted
Requires sophisticated training equipment often seen in rehabilitation or exercise physiology laboratories
Force
An influence applied by one object to another, which results in an acceleration or deceleration of the second object
Length-tension relationship
The resting length of a muscle and the tension the muscle can produce at this resting length
*think “actin-myosin filaments in the sarcomere have the greatest degree of overlap”
Force-velocity curve
Refers to the relationship of muscle’s ability to produce tension of differing shortening velocities
Force couple
Muscle groups moving together to produce movement around a joint
Common Force-couples
- Internal & External Obliques - Trunk rotation
- Upper trapezius & the lower portion of the serratus anterior - upward rotation of the scapula
- Gluteus maximus, quadriceps, & calf muscles - Produce hip & knee extension during walking, running, stair climbing, etc.
- Gastrocnemius, peroneus longus, and tibialis posterior - Performing plantar flexion at the foot and ankle complex
- Deltoid & rotator cuff - Performing shoulder abduction
How many classes of levers are there?
- First - fulcrum (pivot point) in the middle
Ex) Head nod - Second - resistance is in the middle
Ex) Calf raise - Third - effort is placed between the resistance and the fulcrum
Ex) Human forearm
Rotary Motion
Movement of the bones around the joint
Torque
A force that produces rotation. Common unit of torque is the newton-meter or Nm
Motor behavior
Motor response to internal & external environmental stimuli
MB — Motor control; Motor learning; Motor development
Motor control
How the central nervous system integrates internal & external sensory information with previous experiences to produce a motor response
Motor learning
Integration of motor control processes through practice & experience, leading to a relative permanent change in the capacity to produce skilled movements
Motor development
The change in motor skill behavior over time throughout the lifespan
Muscle Synergies
Groups of muscles that are recruited by the central nervous system to provide movement
Sensorimotor Integration
The cooperation of the nervous system & muscular system in gathering and interpreting information & executing movement
*important for proper personal training; incorrect information from proprioception creates incorrect form which leads to injury
What are common muscle synergies?
Squat - Quadriceps, hamstring complex, gluteus maximus
Shoulder press - Deltoid, rotator cuff, trapezius
Feedback
The use of sensory information & sensorimotor integration to help the human movement system in motor learning
2 TYPES
Internal feedback
External feedback
External feedback
Information provided by some external source, such as a health & fitness professional, videotape, mirror or heart rate monitor to supplement the internal environment
*Knowledge of results & knowledge of performance
Internal feedback
The process whereby sensory information is used by the body to reactively monitor movement & the environment
As the velocity of a muscle contraction increases, the ability to produce force decreases for which part of the muscle action spectrum?
Concentric
What refers to a position on the same side of the body?
Proximal
Lateral view - checkpoint LPHC
Compensation
A - Excessive forward lean
B - Low back arches
Probable Overactive Muscles
A - Soleus, gastrocnemius, hip flexor complex, abdominal complex
B - Hip flexor complex, erector spinae, latissimus dorsi
Probably Underactive Muscles
A - Anterior tibialis, gluteus maximus, erector spinae
B - Gluteus maximus, Hamstring complex, Intrinsic core stabilizers
Lateral view - checkpoint Upper Body
Compensation
A - Arms fall forward
Probable Overactive Muscles
A - Latissimus dorsi, Teres major, Pectoralis major/minor
Probably Underactive Muscles
A - Mid/lower trapezius, rhomboids, rotator cuff
Anterior view - checkpoint Feet
Compensation
A - Turn out
Probable Overactive Muscles
A - Soleus, lateral gastrocnemius, biceps femoris (short head)
Probably Underactive Muscles
A - Medial gastrocnemius, medial hamstring complex, gracilis, sartorius, popliteus
Anterior view - checkpoint Knees
Compensation
A - Move inward
Probable Overactive Muscles
A - Adductor complex, biceps femoris (short head), TFL, vastus lateralis
Probably Underactive Muscles
A - Gluteus medius/macimus, vastus medialis oblique (VMO)
