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DPT Biomechanics > Muscle Mechanics > Flashcards

Flashcards in Muscle Mechanics Deck (23):
1

Adverse effects of stretching only occur when the stretch is held for longer than

45 sec

2

What are the acute effects of stretching?

decreased strength, power, speed and movement performance=bad

3

pre-exercise stretching is OK is it lasts less than

30 sec

4

What is the stretch reflex (muscle spindle)

contraction in response to quick stretch

5

What is autogenic inhibition (golgi tendon organ)

immediate inhibition of muscle following contraction

6

What is reciprocal inhibition (muscle spindle)

inhibition of antagonist muscle during agonist contraction

7

Both Length tension and Force velocity assume a single muscle fiber maximally stimulated. what is the difference regarding assumptions

LT - held at a constant length (isometric)
FV - Load is held constant (isotonic) while allowed to shorten or forcibly lengthened

8

What are the effects of aging on skeletal tissue

increased intermuscular adipose tissue
lower neuromuscular activation
properties of single fibers preserved despite reductions in whole muscle CSA
selective atrophy of TYPE II fibers

9

You lose 1% of muscle mass per year after age

40

10

after the age of 40 muscle strength decreases___ as fast

3X

11

T or F Exercise can reverse the effects of aging on skeletal muscle

F. it can slow but not reverse

12

Regarding propulsive energy, which generates more, mono or bi-articulate muscles?

Mono

13

What do bi-articulate muscles allow for?

1- power transfer between joints (net transfer from proximal to distal)
2-efficient conversion of energy into desired movements

14

Multi-joint muscle is unable to contract forcefully in a _____ position

shortened. think forceful fist in wrist flexion

15

what is active insufficiency

decreased tension as length is insufficient (resting length)

16

when a multi-joint muscle is unable to be stretched sufficiently to produce a full range of motion in all the joints simultaneously

passive insufficiency

17

example of passive insufficiency

finger flexion while in wrist flexion

18

What is the role of bi-articular muscles for a uni-articular motion?

role shifts to coordination of movement

19

What is good about stretching?

Increases range of motion
decreases musculotendinous stiffness

20

A tendon is considered to be a _____ component in the biomechanical muscle model

series elastic

21

According to the Lieber article, the eccentric slide of the force-velocity curve tells us muscles are resistant to lengthening. The functional reason for this is

it allows muscles to serve as brakes and to absorb momentum which allows for controlled movement

22

The Henneman size principle states that

small motor neurons are recruited before large neurons to allow smooth and controlled force development

23

According to the concentric slide of the force velocity curve, as contraction velocity increases,

tension development decreases