Exercise Physiology

Front 1

1)What are the functions of skeletal muscles?

Back 1

- locomotion and breathing
- postural support
-Heat production during cold stress
40-50% total body weight

Front 2

a. Epimysium

Back 2

surrounds entire muscle

Front 3

b. Perimysium

Back 3

Surrounds bundles of muscle fibers (Fascicles)

Front 4

c. Endomysium

Back 4

Surrounds individual muscle fibers

Front 5

d. Sarcolemma

Back 5

Muscle cell membrane

Front 6

3) Explain the role of satellite cells with muscle development

Back 6

Play role in muscle growth and repair
a. Increase number of nuclei

Front 7

4) What is a sarcomere?

Back 7

a. Includes Z line, M line, H zone, A band, I band
b.s the basic unit of a muscle. Muscles are composed of tubular muscle cells (myocytes or myofibers). Muscle cells are composed of tubular myofibrils. Myofibrils are composed of repeating sections of sarcomeres, which appear under the microscope as dark and light bands. Sarcomeres are composed of long, fibrous proteins that slide past each other when the muscles contract and relax.

Front 8

5) Describe the ‘Sliding Muscle Filament’ theory

Back 8

• muscle shortening occurs due to movement of the actin filament over the myosin
filament.



• The steps in muscular contraction are:
a. The nerve impulse travels down the transverse tubules and reaches the sarcoplasmic reticulum, and Ca+2 is released.
b. Ca+2 binds to the protein troponin.
c. Ca+2 binding to troponin causes a position change in tropomyosin away from the “active sites” on the actin molecule and permits a strong binding state between actin and myosin.
d. Muscular contraction occurs by multiple cycles of cross-bridge activity. Shortening will continue as long as energy is available and Ca+2 is free to bind to troponin.

Front 9

6) What are actin and myosin?

Back 9

Myofibrils contain two major types of contractile protein: (1) actin (part of the thin filaments) and (2) myosin (major component of the thick filaments).

Front 10

7) What are the 3 main muscle fibers?

Back 10

Type IIx fibers
a. Fast-twitch fibers
b. Fast-glycolytic fibers
Type IIa fibers
c. Intermediate fibers
d. Fast-oxidative glycolytic fibers
Type I fibers
e. Slow-twitch fibers
f. Slow-oxidative fibers

Front 11

8) Explain the role of aging and atrophy of muscle fibers

Back 11

Loss of muscle mass and strength
a. Due to prolonged bed rest, limb immobilization, reduced loading during space flight
Initial atrophy (2 days)
b. Due to decreased protein synthesis
Further atrophy
c. Due to reduced protein synthesis
Atrophy is not permanent
d. Can be reversed by resistance training
e. During spaceflight, atrophy can be prevented by resistance exercise

• Prolonged periods of muscle disuse (bed rest, limb immobilization, etc.) result in muscle atrophy. This inactivity-induced atrophy results in a loss of muscle protein due to a reduction in protein synthesis and an increase in the rate of muscle protein breakdown.

Front 12

9) ***Identify and describe 3 types of muscle action

Back 12

Isometric (static)
a. Muscle exerts force without changing length
b. Pulling against immovable object
c. Postural muscles
Ex: push brick wall for 15 seconds.

Isotonic (dynamic)
– Concentric
• Muscle shortens during force production
– Eccentric
• Muscle produces force but length increases
– Includes variable resistance exercise
• Nautilus equipment
Ex: bicep curls
Isokinetic

– Exertion of force at constant speed
Ex: expensive monitoring force production match force device found in pt clinic-rehab athletic performance

Front 13

10) ***What are the 3 main principles of training and describe each one

Back 13

Overload
a. Training effect occurs when a system is exercised at a level beyond which it is normally accustomed
Specificity
b. Training effect is specific to:
i. Muscle fibers involved
ii. Energy system involved (aerobic vs. anaerobic)
iii. Velocity of contraction
iv. Type of contraction (eccentric, concentric, isometric)
Reversibility
c. Gains are lost when overload is removed
d. When training is stopped, the training effect is quickly lost

Front 14

12) What are factors that improve Vo2 max physiologically

Back 14

• Genetic predisposition accounts for 40% to 60% of one’s VO2 max value. Very strenuous and/or prolonged training can increase VO2 max in normal sedentary individuals by more than 40%.

• In young sedentary subjects, approximately 50% of the increase in VO2 max due to training is related to an increase in maximal stroke volume (maximal heart rate remains the same), and 50% is due to an increase in the a-vO2 difference.
• The large differences in VO2 max in the normal population (2 versus 6 liters/min) are due to differences in maximal stroke volume.

• Higher VO2 max due to:
– Higher maximal cardiac output, stroke volume, and lower total peripheral resistance
– No difference in a-vO2 difference or maximal
heart rate
• Higher stroke volume linked to:
– Higher blood volume and red cell volume
• The increased a-vO2 difference is due to an increase in the capillary density of the trained muscles that is needed to accept the increase in maximal muscle blood flow. The greater capillary density

Front 15

13) What happens during lactate removal, What is responsible for this?

Back 15

a. By nonworking muscle, liver, and kidneys
b. Gluconeogenesis in liver

Front 16

14) Define muscular strength vs. muscular endurance

Back 16

Muscular strength
a. Maximal force a muscle or muscle group can generate
i. 1 repetition maximum (1-RM)
Muscular endurance
b. Ability to make repeated contractions against a submaximal load

Front 17

15) What is sarcopenia?

Back 17

Decline in strength after age 50
a. Loss of muscle mass (sarcopenia)
i. Loss of both type I and II fibers
ii. Atrophy of type II fibers
iii. Loss of intramuscular fat and connective tissue
b. Loss of motor units
c. Reorganization of motor units

Front 18

16) ***Explain how ‘neural factors’ are responsible for strength improvements?

Back 18

Early gains in strength
a. Initial 8–20 weeks
Adaptations
b. Improved ability to recruit motor units
c. Learning
d. Coordination

Front 19

17) What is the difference between hypertrophy vs. hyperplasia?

Back 19

Hypertrophy
a. Enlargement of both type I and II fibers
i. Low-intensity (high RM), high-volume training results in smaller type II fibers
ii. Heavy resistance (low RM) results in larger type II fibers
b. No increase in capillary density
Hyperplasia
c. Increase in muscle fiber number
d. Mainly seen in long-term strength training
i. Not as much evidence as muscle hypertrophy

Front 20

18) Define the term ‘epidemiology’

Back 20

The study of the distribution and determinants of health states and the use of this information in the control of disease
Uses of epidemiology:
a. Establish the cause of disease
b. Trace the natural history of disease
c. Describe the health status of populations
d. Evaluate an intervention

Front 21

19) What are the top 3 killers in the U.S. in correct order?

Back 21

-heart diseases
-cancer
-strokes

Front 22

21) What are 4 characteristics of Metabolic Syndrome?

Back 22

Insulin resistance
a. Reduced ability of peripheral tissues to take up glucose
b. Leads to hyperinsulinemia
i. Due to higher insulin secretion by pancreas
c. Also increases FFA level in the blood
i. Together with abdominal obesity
Hyperinsulinemia associated with:
d. Increased SNS activity
e. Increased sodium and water retention
f. Increased smooth muscle proliferation in blood vessels

• Several competing hypotheses
• Insulin resistance
– Changes in blood vessels and water retention cause hypertension
• Hypertension
– Decrease in small blood vessels reduces glucose and insulin delivery to muscle, causing insulin resistance
• Increased SNS activity
– Increases blood pressure and blood glucose
• Obesity
– Adipose tissue secretions affect insulin resistance

Front 23

22) What is a PAR-Q?

Back 23

Physical Activity Readiness Questionnaire (PAR-Q)

Front 24

23) List physiological readings taken at rest and at exercise for assessments

Back 24

Resting measures
a. Heart rate and blood pressure *
b. Cholesterol
c. ECG
Exercise measures (GXT or field test)
d. Heart rate
e. Blood pressure
f. ECG
g. Symptoms
i. Angina pectoris *
ii. Dyspnea *

Front 25

24) Differences between field tests vs. laboratory testing

Back 25

(Field test)
Use natural activities
a. Walking, running, or stepping
Can test large numbers of people at low cost *
Physiological responses may be difficult to measure
Motivation plays an important role in test results

Cr-field test
• Measure how far a person can run in a set time or how fast they can run a set distance
– Cooper’s 12-minute run and 1.5-mile run *
• For adults
– AAPHERD’s 1-mile run/walk and PACER test *
• For children
• VO2 max estimates based on the linear relationship between running speed and oxygen cost of running*
– Duration of 10–20 minutes
• Running at speed demanding 90–95% VO2 max
• Minimize contribution of anaerobic energy sources
Progressive Aerobic Cardiovascular Endurance Run (PACER)
Walk Tests aka Rockport Test
Queen’s College Step Test for Determining Vo2 *

(laboratory testing) graded exercise test
– Treadmill
– Cycle ergometer
-bod pod
-bike test
-dexa

Front 26

25) Recognize the difference types of field tests vs. lab tests for fitness testing

Back 26

.

Front 27

26) What is a RPE and why would one use this instead of checking heart rate?

Back 27

• Original 6–20 scale and revised scale (0–10)
• Indicator of subjective effort
– Way to track progress through a GXT 1 3-15 medication
– Can be used to prescribe exercise

Front 28

27) ***Define and describe the acronym for FIT

Back 28

a. Intensity
i. %VO2 max
ii. % maximal heart rate
iii. Rating of perceived exertion
iv. Lactate threshold
b. Frequency
i. Number of days per week
ii. Number of times per day
c. Duration
i. Number of minutes of exercise
ii. Total kcals expended
iii. Total kcals expended per kilogram body weight

Front 29

28) What are the general requirements for a training program?

Back 29

Training program should match the anaerobic and aerobic demands of the sport *
Overload *
a. Increased capacity of a system in response to training above the level to which it is accustomed
Specificity *
b. Specific muscles involved
c. Specific energy systems that are utilized
Reversibility *
d. When training is stopped, the training effect is quickly lost

• Men and women respond similarly to training programs *
– Exercise prescriptions should be individualized
• Training improvement is always greater in individuals with lower initial fitness *
– 50% increase in VO2 max in sedentary adults
– 10–15% improvement in normal, active subjects
– 3–5% improvement in trained athletes

Front 30

29) What are the ACSM recommendations for prescribing cardio and strength training?

Back 30

ACSM recommendation
a. One set of 8–10 exercises (major muscle groups)
b. 8–12 reps per set
c. 2–3 sessions per week
Multiple sets more effective for improving strength
Single set sufficient when maximal strength gain is not the primary goal
For maximal gains in strength
d. Untrained: four sets at 60% 1-RM, three days/week
e. Trained: four sets at 80% 1-RM, two days/week
f. Athletes: eight sets at 85% 1-RM, two days/week

Front 31

30) What is DOMS and what is responsible for this?

Back 31

Delayed onset muscle soreness (DOMS)
– Slowly begin a specific exercise over 5–10 training sessions to avoid DOMS


Due to microscopic tears in muscle fibers or connective tissue
Results in cellular degradation and inflammatory response
Not due to lactic acid
Eccentric exercise causes more damage than concentric exercise

Front 32

31) What are the 2 main types of stretching techniques?

Back 32

Static stretching
a. Continuously holding a stretch position
i. Hold position for 10–60 seconds
ii. Repeat each stretch 3–5 times
b. Preferred technique
i. Less chance of injury or soreness
ii. Less muscle spindle activity
Dynamic stretching
c. Ballistic stretching movements