Lesson 3: Muscle Physiology

Question 1

The Muscular system is comprised of three types of muscle tissue:

Answer 1

Skeletal
Cardiac
Smooth

Question 2

A muscle fiber is either in a state of producing maximum tension or not producing any tension at all; this is known as the “____ ____ _____” principle.

Answer 2

All or nothing

Question 3

Cylindrical structures containing the myofilaments actin and myosin.

Answer 3

Myofibrils

Question 4

Thin myofilaments

Answer 4

Actin

Question 5

Thick myofilaments

Answer 5

Myosin

Question 6

Wave-like changes in the electrical properties of a cell membrane.

Answer 6

Action potential

Question 7

Striated muscle used the facilitate movement.

Answer 7

Skeletal muscle

Question 8

Acts as a storage site for calcium

Answer 8

Sarcoplasmic reticulum

Question 9

_________ firing - employed during high-output demands involving fast twitch fibers and warranting significant fiber recruitment.

Answer 9

Synchronized

Question 10

_________ firing - employed during endurance activities involving slow twitch fibers which conserve motor unit potential, allowing prolonged work

Answer 10

Asynchronized

Question 11

The ability to increase force production within a muscle through training is dependant on adaptions that occur to both: _______ and ________

Answer 11

Muscle Fibers (size)
The Nervous System

Question 12

List 3 ways in which the nervous systems allows for improvements in force production within muscle.

Answer 12

Increased Firing Rate
increased Recruitment
Increased Synchronicity

Question 13

_______ contractions - involve lengthening or shortening of a working muscle.

Answer 13

Isotonic

Question 14

_______ contraction - Muscle lengthens; negative work is produced; movement is decelerated

Answer 14

Eccentric

Question 15

_______ contraction - Muscle shortens; positive work is produced; movement is accelerated.

Answer 15

Concentric

Question 16

_______ contractions - Mostly used for stability, represents tensions in the muscle that helps maintain a stable position

Answer 16

Isometric

Question 17

Oxygen- transporting protein of muscle.

Answer 17

Myogoblin

Question 18

Muscle found exclusively within the heart.

Answer 18

Cardiac Muscle

Question 19

Muscle found within the “walls” of hollow organs.

Answer 19

Smooth Muscle

Question 20

Period of time between repeated actions in an exercise; energy system specific and based on physical condition.

Answer 20

Rest Interval or Rest Period

Question 21

Period of time between exercise bouts.

Answer 21

Recovery Period

Question 22

Low force-producing fibers, or slow oxidative fibers.

Answer 22

Type 1

Question 23

Intermediate force-producing fibers, or fast oxidative/glycolytic fibers.

Answer 23

Type 2a

Question 24

High force-producing fibers, or fast glycolytic fibers.

Answer 24

Type 2b

Question 25

Postural muscles maintain a higher concentration of ____- twitch fibers.

Answer 25

Slow

Question 26

Some motor units in a muscle are always active even when the muscle is not contracting.

Answer 26

Muscle tone

Question 27

Intrafusal fibers that lie parallel to normal muscle fibers which relay information to sensory neurons regarding changes in tissue length.

Answer 27

Muscle Spindles Note: When Rapidly Stretched , they respond with a stretch reflex to initiate a contraction that limits an overstretch and potential damage to the muscle.

Question 28

Sensory receptors found within muscle tendons that communicate information to motor neurons regarding the presence of excessive tension that may cause damage.

Answer 28

Golgi tendon organs

Question 29

Muscle fibers can become better suited to a specific training stimulus due to the following 3 adaptions.

Answer 29

Neural Stimulation Capillary and Mitochondrial density Enzyme concentration