Exercise Physiology

Question 1

innervation ratio

Answer 1

number of muscle fibers innervated by single motor neuron

Question 2

muscles with high IR

Answer 2

gastrocnemius
quadriceps

for sprinting and jumping

Question 3

more excitable, conducts action potentials more slowly

Answer 3

small-diameter motor neuron

Question 4

less excitable, conducts action potentials more rapidly

Answer 4

large-diameter motor neuron

Question 5

strength (anaerobic) training motor unit

Answer 5

Type IIx motor unit

Question 6

endurance (aerobic) training motor unit

Answer 6

type I and type II a

Question 7

work formula

Answer 7

force X distance

Question 8

power formula

Answer 8

work/time

Question 9

force developed by cross-bridges exceeds external load, sarcomeres shorten

Answer 9

concentric contraction

Question 10

force developed by cross-bridges is less than imposed load, sarcomeres lengthen

Answer 10

eccentric contraction

Question 11

what muscle contraction puts more stress on muscles –> damage muscle fibers and CT?

Answer 11

eccentric contraction

Question 12

common eccentric contraction muscle injury

Answer 12

rupture of achilles tendon

Question 13

strength of muscle is determined by ____.

Answer 13

muscle size and testosterone level

Question 14

what does endurance of muscle depend on?

Answer 14

nutritive support = amount of glycogen stores

Question 15

high carb diet glycogen stored in muscle (g/kg)

Answer 15

40

Question 16

mixed diet glycogen stored

Answer 16

20 g/kg

Question 17

high fat diet glycogen stored

Answer 17

6 g/kg

Question 18

products of phosphagen system

Answer 18

ATP and phosphocreatine

immediate energy source BUT LIMITED

Question 19

what is the effect of decreased pH on contractile force of muscle?

Answer 19

it impairs contractile force of muscle.

Question 20

central CNS fatigue is less likely to occur in what kind of individuals?

Answer 20

highly trained athletes

Question 21

central CNS fatigue is more likely to happen in..

Answer 21

novice athletes/individuals

Question 22

what kind of external stimulus will increase muscle force production and physical performance?

Answer 22

sensory input – shouting and cheering

Question 23

cause of peripheral fatigue

Answer 23

impaired excitability, impaired calcium release

Question 24

reduced excitatory input to motor centers of brain and SC can lead to

Answer 24

central CNS fatigue

Question 25

normal O2 consumption of untrained average male

Answer 25

3.6 ml/min

Question 26

normal O2 consumption of mildly active adult

Answer 26

30-40 ml/min

Question 27

normal O2 consumption of endurance athlete

Answer 27

80-90 ml/min

Question 28

breathing capacity at maximal exercise

Answer 28

100 - 110 L/min

Question 29

maximal breathing/lung capacity

Answer 29

150 - 170 L/min

Question 30

normal breathing/lung capacity

Answer 30

4.5 - 6 L/min

Question 31

BF during maximal exercise

Answer 31

90 ml/100 g muscle/min

Question 32

resting BF

Answer 32

3.6 ml/100 g muscle/min

Question 33

sweat glands found in armpit and pelvic area

Answer 33

apocrine gland

Question 34

sweat glands found all over the body and play a role in temperature regulation

Answer 34

eccrine gland

Question 35

sweat gland found largely in palms of hand and soles of feet

Answer 35

eccrine gland

Question 36

psychic stimulants

Answer 36

amphetamine, cocaine

Question 37

negative effect of amphetamine, cocaine

Answer 37

overexcitability of heart which can lead to VFib

Question 38

benefits of aerobic training

Answer 38

• enhances O2 diffusion into muscle
• ## increases mitochondrial content

Question 39

how does aerobic training increase maximal O2 deliverY?

Answer 39

by increasing plasma volume & maximal CO