strength and conditioing

The flashcards below were created by user cgat45 on FreezingBlue Flashcards.

  1. biomechanics
    • the science of applying the principles of mechanics to biological systems.
    • study of angles and human motion
    • concepts apply to all motor skills performed in sports as well as all training modalties
    • affect ones acute level of force power prodluction and subsequent increases in muscle strength
  2. kinetics
    • a branch of biomechanics that deals with the forces that cause motion
    • force production embodies numerous mechanisms and interactions between the nervous, muscular, connective tissue , metabolic, and endocrine systems
  3. kinematics
    • descritpiton of motion
    • displacement
    • position
    • velocitly
    • acceleration
  4. what actions are predominate during agonist prescribed movements
    • con
    • ecc
  5. isokinetic
    • velocity controlled con and ecc muscle actions
    • machine minipulation
    • devices enable strenght testing or training at slow, moderat, and or fast velocities
  6. skeletal muscle length plays an important role in
    • force production
    • (length tension relationship)
  7. accourding to the muscle length curve where is the greatest tension produced
    in the middle slightly past resting muscle length.
  8. sarcomere
    • the functional component of a muscle fiber
    • shows the optimal interaction of the maximal number of muscle contractile proteins acin and myosin
  9. active muscle length tension relationship
    • muscle tension is proportional to the number of cross bridges formed between actin and myosin filaments. passive elements are minimal
    • tensions is greatest in the middle segment of the cureve but lessens as cross bridge numbers decrese at both shorter and longer muscle lengths
  10. passive muscle length relationship
    passive elements contribute greatly to longer muscle lengths
  11. active elements
    contributing greatly from short to moderate lenghts
  12. passive elements
    contributing greatly at moderate to longer lengths
  13. what happens at shorter muscle lengths
    there is overlap of the actin filaments, which reduces actin and myosin interaction. because muscle tenstion is proportionate to the number of cross bridges formed, shorter lengths geometrically pose a problem reducing active muscle tension.
  14. what happens in a longer muscle length
    • cross bridge formation is reduced making the mysoin filiament unable to reach as many actin filiaments
    • passive neuromuscular elements need to be considered and at longer lengths they contribute highly to the rebound of muscle tension.
  15. although cross bridge interaction is minimal at long muscle lengths, tension rebounds mostly due to
    resistance to stretch from tendons and skeletal muscle fascia along with some tension produced withing the contractile and structural proteins
  16. stretch shortening cycle
    • human movement that begins with a windup or countermovemnt results in a more powerful action when the movement is reversed. ecc muscle action that precedes a con action results in a more forceful con action
    • allows the athlete to develop large force and power outputs
    • consists of the stretch reflex and the muscles ability to store elastic energy within its series and parallel elastic components
    • critical that a con action follows right away any pause between the ecc and con phase results in attenuated performance
  17. storage of elastic energy
    contributes mostly up to about 70% of the stretching shortening cycle
  18. stretch reflex
    • is initiated by a specifc sensory receptor, the muscle spindle, which responds to both the magnitude and rate of muscle length change.
    • resulting effect is that the ssc can enhance performance by an average of 15-20%
  19. ssc is mot prominent in
    • fast twitch fibers
    • and is highly trainable via plyometric, sprints agility, and resistacne training
  20. fast twitch fibers
    • ft fiber motion is faster resulting in greater elastic energy storage
    • generaly
  21. velocity of muscle contraction plays a critical role in
    the magnitude of force produced.
  22. force velocity relationship
    • shows skeletal muscle fibers produce force to match external loading
    • increasing velocity of shortening during light loading and decreasing in velocity of shortening with greather loading
  23. con and cross bridge formation
    • at slower velocities of contraction whereas less force is produced at fast velocities of contractions
    • therfore force increases as velocity slows and decreases as velocity increases
    • cross bridges formed once agian and actin filaments slide rapidly at fast velocities, therby making it more difficult for mysoin to form cross bridges with actin.
    • as cross bridges cycling tare increases less cross bridges remain intact at any given time
  24. isom and crossbridge formation
    • cross bridge formation is enhanced at slow velocities and during isom actions where the cross bridge cycling rat is low
    • the reult is greater force production
  25. during ecc actions
    • muscle force increases as velocity increases
    • loading greater than peak isom force level causes muscle fibers to lengthen.
    • additional loasding increases the lengthening velocity increases beacuse the fibers are contracting as they are lengthening and greater force is present during ecc actions
  26. skeletal muscle architecuter
    • refers to the size and arrangement of muscle fibers relative to the muscles line of pull
    • features of skeletal muscle include the length of fasicles, fibers, and the arrangement of muscle fibers.
  27. muscle line of pull dectates
    the direction of the joint that ensues as muscle fibers shorten
  28. nonpennate muscles
    • have their fibers run parallel to the muscles line of pull
    • anything that is not 90 degress or 180 degress
    • have longer fiber lengths and are typically fewer in number
    • thus nonpennate muscle fiber arrangement is more advantageous for range of motion and speed contraction
  29. types of nonpennate muscles
    • longitudinal muscles (strap)- sartorius and rectus abdonminis are long in length
    • quadrate (quadrilateral) muscles- rhomboids, are flat, four sided nonpennated muscles
    • fan-shaped  (radiate, triangular) muscles- pectoralis major, gluteus medius
    • fusiform muscles- biceps brachii and brachioradialis, are rounded, spindle shaped muscles that taper at both ends
  30. pennate muscle
    • are arranged obliquely to the central tendon or line of pull
    • arrangement shorter firbers oriented at an angle, is advantageous for strength and power production but not as much for velocity of contraction and rom
    • enables greater fiber number per cross sectional area
    • shorter fiber lenght coupled with greater fiber packing density yields greater force and power production compared to nonpennate muscles of similar volume
    • can be advantageous over time cause a chronic increase in the angle of mennation at reast creates space for muscle hypertrophy
  31. types of pennate muscles
    • unipennate muscle
    • bipennate muscle
    • multipennate muscle
  32. unipennate muscle
    tibialis posterior, has one column of fibers that are arranged at an angle to the line of pull
  33. bipennate muscle
    rectus femoris, has a long central tendon with fibers extending diagonlly in pairs from eithr side in two columns
    deltoid , has more thatn two columns of fibers converging on a tendon to form one muscle.
  35. in pennate muscle the angle of pennation refers to
    • the angle between the fibers and the central tendon.
    • the larger the angle of pennation the smaller amount of force transmitted to the tendon
  36. physiologi cross sectional area
    sum total of all fivers cross section in a plane perpendicular to fiver orientation
  37. forces are described by
    their magnitude  direction and point of application
  38. linear motion
    • accurs when all point on a body or boject move the same distance, at the same time, and in the same direction, thereby yielding a straight(rectilinear motion) or curved (curvilinear motion) pathway
    • centric and eccentric forces can produce linear motion
  39. angular motion
    • counterpart to linear motion
    • occurs when all points on a body or object move in circluar pattern around the same axis
    • angular motion of the bodily segments can produce linear and angular motion of the entire body
    • eccentric forces and force couples produce angular motion
  40. torque
    • also known as moment
    • is the rotation caused by a force about a specific axis and is the product of force and moment arm length
    • thr force may be directed throough the objects center of gravity
  41. centric force
    force may be directed through the cog
  42. eccentric force
    away from cog
  43. force couple
    or multiple forces may be equal in size but opposite in direction
  44. moment arm or lever arm
    • is the perpendicular distance between the forces line of action and the fulcrum
    • may also be  the perpendicular distance between the reisitance and flucrum
  45. two types of moment arms
    • moment arm of force
    • moment are of resistance
  46. moment arm of force
    formed between the point of muscle attachment and the joint
  47. moment arm of resistance
    between the joint and where the loading is concetrated
  48. levers
    • are used to overcome a large resistance and is used to enhance speed and rom
    • made up of fulcrum(pivot point), resistance, and force
  49. resistance arm
    the distance  from the fulcrum to the concetration of the resistance
  50. effort arm
    the distance from the fulcrum to the concentration of the force
  51. first class lever
    • the elbow during extension
    • has its fulcrum lie between the force and resistacne
    • speed and rom are maximized with this type of lever and force is secondary
    • is a mechanical disadvantage
  52. second calss lever
    • standing plantar flexion onto the toes
    • has its resistance lie between the fulcrum and force
    • advatage with this type of lever is force
    • effort arm is larger thatn the resistance arm
  53. third calss lever
    • elbow during flexion
    • has its force lie between the fulcrum and resistance
    • more advantageous for speed and rom and not as much for force
    • most single joing movements in the human body operat via third class levers
    • mechanical disadvanteges adn are more suitable for greater joint angular velocities as the resistance arem is larger thatn the effort arm
  54. in leverage system
    • bones act as levers
    • joints act as flucrums
    • and contracting skeletal muscles act as the force
  55. mecahnical advatage
    is the ratio of the moment arm of muscle force (effort arm) to the moment arm of resistance (resistance arm)
  56. vale of 1
    indicates balance between the effort and resistance arms
  57. value greater then 1
    indicated a mechanical advantage where torque created by the effort force is magnigified
  58. value less then 1
    • indicates a mechanical disadvantage( altough it would be an advatage for speed and rom
    • where a larger effort force is needed to over come the resistance
Card Set:
strength and conditioing
2012-09-23 21:27:12

Show Answers: