Body Systems Overview

Question 1

Describe the pulmonary circuit

Answer 1

the R side of the heart receives de-oxygenated blood via the pulmonary arteries (exception to the artery rule) and backflow is prevented via the semi-lunar valve

Question 2

Describe the systemic circuit

Answer 2

the L side of the heart receives oxygenated blood via the pulmonary veins (the exception to the vein rule) and backflow is prevented via the pulmonary semi-lunar valve

Question 3

What are the components of blood?

Answer 3

1. formed= RBCs, WBCs, platelets

2. plasma–> transport of plasma proteins, hormones, nutrients, ions, gases

Question 4

How much air do humans breathe at rest vs. exercise?

Answer 4

Rest= 5-6L apm via nose
Exercise= 20-30L apm

Question 5

What does the Mediastinum house?

Answer 5

heart, trachea, aorta, esophagus, part of trachea

Question 6

Muscles working for inspiration at rest vs. exercise

Answer 6

Rest= diaphragm and external intercostals
Exercise= (+) pec minor, scalenes, sternocleidomastoid

Question 7

Muscles working for expiration at rest vs. exercise

Answer 7

Rest=passive
Exercise= Rectus Abdominis, Int Obliques, Serratus, int. intercostals to force air from lungs by squeezing abdominal organs UP against the diaphragm

Question 8

Tell me about the Lymphatic system?

Answer 8

prevent Edema of interstitium by returning excess fluids to bloodstream

• similar to blood but no RBCs or platelets
• enters blood through lymphatic capillaries–> arteries–> blood capillaries–> veins

Question 9

4 Major roles of the Lymphatic system

Answer 9

1. destruction of bacteria and foreign substances
2. immune response to make antibodies
3. return of the interstitial fluid to blood stream
4. prevention of excess accumulation of tissue fluid/filtered proteins by drainage into highly permeable lymphatic capillaries in connective tissues

Question 10

Define cardiorespiratory endurance and the 3 reasons it’s important

Answer 10

capacity of heart and lungs to deliver blood + O2 to working muscles during exercise
Important for:
1. O2 transported in blood used for ATP production
2. Waste removal (CO2 and lactate)
3. dissipation of heat produced during these metabolic processes

Question 11

What are the 3 processes for adequate blood and nutrients to tissue

Answer 11

1. O2 carrying capacity
2. O2 delivery (most important for CR endurance)
3. Oxygen Extraction (At cellular level to make ATP)

Question 12

What is anemia?

Answer 12

low Hemoglobin (less than 12 Hb per 100 mL of blood)

Question 13

Explain the significance of O2 delivery

Answer 13

Resting Q= 5L per min
Active Q=20-25L, up to 30-40 L per min
With exercise, HR goes up, SV increases up to about 40-50% max capacity then plateaus
SV increases due to increase EF (50-60% at rest to 60-80% during exercise) AND increase in VR

Question 14

Afferent vs. Efferent divisions of the NS

Answer 14

afferent- sensory division carries impulses to CNS

efferent- motor division carries impulses from CNS

Question 15

What is a Golgi Tendon Organ?

Answer 15

located between the muscle belly and its’ tendon
recognizes tension in the muscle (whether its being stretched too much or contracted too tightly) and will cause autogenic inhibition (relax the muscle via contraction of the agonist muscle group) as observed during static stretching

Question 16

What is a muscle spindle?

Answer 16

located in the belly of muscle parallel to fibers
senses the stretch of a muscle, and in response, the muscle spindle will also stretch and cause a reflexive contraction known as the stretch reflex, causing the antagonist muscle to relax via reciprocal inhibition
-this is observed during PNF where low grade muscle contraction (about 50% max) of an antagonist muscle for 6-15s will inhibit or reduce muscle spindle activity w/in agonist muscle (Allows muscle to be stretched).

Question 17

Describe the 3 types of muscle

Answer 17

1. skeletal- striated w/ light and dark bands, considered voluntary
2. smooth- no striation, considered involuntary
3. cardiac muscle- striated, considered voluntary

Question 18

What do tendons do?

Answer 18

connect muscle to bone

proximal end is usually less mobile than distal

Question 19

4 Types of muscle fiber arrangements:

Answer 19

1. longitudinal “strap-like”, fibers run parallel to the long axis of the bone (relatively weak)
2. Unipennate- all fibers insert into one side of the tendon, tendon runs entire length of muscle
3. Bipennate- muscle fibers insert obliquely onto each side of tendon
   Unipennate and bipennate create less movement but greater force than longitudinal
4. multipennate- complex arrangement of muscle fibers and involves convergence of several different tendons

Question 20

Describe Type 1 Muscle fibers

Answer 20

slow-twitch, oxidative, more capillaries/mitochondria, more hemoglobin, more efficient aerobically, resistant to fatigue, lower force outputs, slower

Question 21

Describe Type 2 Muscle fibers

Answer 21

Type 2x (fast-glycolytic) have small # mitochondira, limited aerobic capacity, can’t sustain effort for more than a few seconds but have a high number of glycolytic enzymes for large anaerobic capacity (the largest and fastest type)

Type 2a (intermediate or fast-oxidative glycolytic fibers) have speed, fatigue resistance, intermediate force production, can be sustained up to 3min, highly adaptive and can increase oxidative capacity with training

Question 22

What are the 3 main layers of muscle?

Answer 22

Epimysium- fascia that encases entire muscle
Perimysium- fibrous sheet of fascia that encases bundle of muscle fibers
Endomysium- individual muscle fibers wrapped in fascia

Question 23

Describe the components of muscles that allow them to contract?

Answer 23

Myofibrils (aka protein filaments) of muscle run parallel to each other
Dark (A bands) contain Myosin
Light (I bands) contain Actin
Actin and Myosin overlap
Sarcomere is the functional contracting unit of skeletal muscle and is the portion of myofibril that is found between 2 Z-lines
H-zone contains only myosin filaments and is located in the center of a sarcomere

Question 24

What is the sliding filament model

Answer 24

ACH is released at neuromuscular junction, which triggers release of Ca+ which exposes binding sites along the actin filament for the myosin filament, so cross bridges can be formed w/ sufficient ATP present, the myosin pulls actin toward the center and the sarcomere shortens (Z lines are pulled closer together)

Question 25

What are the different types of connective tissue?

Answer 25

Collagen- most abundant protein, tensile strength and inextensibility, main constituents of ligaments and tendons (subfribils w/ crimps), can only be stretched about 3%
Elastin- elastic fibers made of AA, disseminate mechanical stress, defend against excessive forces, assist organs in returning to pre-force state, can be streteched up to 150% original length
almost always found with collagen in the body

Question 26

Are ligaments or tendons more flexible?

Answer 26

Ligaments are more flexible- contain greater mix of collagen and elastin

Question 27

How do connective tissues contribute to movement?

Answer 27

Tendons provide about 10%, ligaments + joint capsule 47% of total resistance, fascia 41%, skin 2%

Question 28

What is Fascia

Answer 28

1. Superficial- lies directly below skin and contains collection of fat
2. Deep (intramuscular)- directly beneath superficial, tougher, tighter, more compact, encases muscles, organs, blood vessels
3. subserous- forms the fibrous layer of serous membranes that cover and support the innermost body cavities (ie, pleura around lungs, pericardium around heart)

Question 29

What are the roles of deep Fascia

Answer 29

1. provide a framework for proper alignment of muscle fibers, blood vessels, nerves
2. safe and effective transmission of forces through the muscle
3. lubricate muscle fibers to allow change in shape during contraction and elongation

Question 30

What are the mechanics of effective stretching?

Answer 30

slight overlap of filaments w/ at least one cross-bridge maintained between actin and myosin (50-67% longer than resting length)

Question 31

Define Autogenic Inhibition

Answer 31

activation of GTO inhibits a muscle spindle response (temporarily inhibits muscle spindle 7-10s after activation) allowing muscle to stretch farther (going past 10s can place stress on collagen fibers, remodeling them as they pull apart (plastic deformation)

• creep- the lengthening that occurs when a stretch force is applied
• reduced tension and creep are possible explanations for increases in ROM after an acute static stretching session, after termination of stretch, 70% recovery of muscle spindly within first 5s

Question 32

Define Reciprocal Inhibition

Answer 32

activation of the agonist muscle coincides with neural inhibition of the opposing muscle on the other side of the joint when a contraction or active movement of agonist muscle is performed (at less than 50% max) for more than 6s, the antagonist is inhibited (reduced muscle spindle activity) allowing it to be stretched

Question 33

Does static stretching elicit the stretch reflex?

Answer 33

no

Question 34

What is PNF?

Answer 34

capitalizes on principles of autogenic inhibition AND autogenic inhibition
*initially used to treat tissue tonicity in a rehab setting

Question 35

What is the hold-relax technique?

Answer 35

(autogenic inhibition)

1. Passive pre-stretch for 10s
2. Individual holds and resists force provided by fitness professional to create isometric muscle contraction in target muscle for 6s
3. Passive stretch for 30s

Question 36

What is the contract-relax technique?

Answer 36

(autogenic inhibition)

1. Passive pre-stretch for 10s
2. Individual pushes against force by completing a concentric muscle contraction through full range of motion
3. Passive stretch for 30s

Question 37

What is the hold-relax w/ agonist contraction technique?

Answer 37

1. Passive pre-stretch for 10s
2. Individual holds and resists force provided by fitness profession to create isometric muscle contraction in target muscle for 6s, THEN concentric action of opposing muscle group is added to the final passive stretch (for example, fitness professional gently pushed on leg while individual tries to create hip flexion in a lying-down hamstring stretch)

Question 38

What is ballistic stretching?

Answer 38

Begin with slow, short-end range (SSER movements)
Progress to slow, full-range (SFR movements)
Progress to fast, short-end range (FSER movements)
End with fast, full-range (FFR movements)

Question 39

What is active isolated stretching?

Answer 39

repeated progression of stretches of an isolated muscle, lasting only about 2s, can use rope or towel (example: calf stretches)

Question 40

What is myofascial release and why is it important?

Answer 40

foam roller over section 2-6 inches for 30-60s
Myofascial release realigns the elastic muscle and connective tissue fibers from a bundled position (called a knot or adhesion) into a straighter arrangement, and resets the proprioceptive mechanisms of the soft tissue, thus reducing hypertonicity within the underlying muscles
Purpose of fascia- contains muscle groups, and orients muscle fibers in a vertical direction
-it is thought that applying sustained pressure to a tight area can inhibit the tension in a muscle by stimulation the GTO to bring about autogenic inhibition

Question 41

What are the recommendations for optimal static stretch time?

Answer 41

varies from 3-60s, 15-30s currently appears to be most effective for increasing ROM and should be repeated 3-4x when muscle is warm