muscle part 3

Question 1

force of contraction affected by

Answer 1

frequency of stimulation
length-tension relationship

Question 2

length tension relationship

Answer 2

muscles contract most strongly when fibers are 80-120% of their normal length

more length= more tension
less length= less tension

Question 3

how to increase contractile force?

Answer 3

1. activate a larger # of muscle fibers
2. activate large (size) muscle fibers
3. increase frequency of stimulation
4. stretch out muscle- but not too much or actin and myosin won’t overlap

Question 4

duration and velocity of contraction influenced by…

Answer 4

1. muscle fiber type (3 kinds)
2. load
3. recruitment

Question 5

how is muscle fiber classified

Answer 5

1. enzyme: fast or slow muscle contraction
2. metabolic pathway for ATP synthesis:

-oxidative fibers use aerobic pathways (slow twitch) smaller, darker (because of more myoglobin due to more oxy), more resistant to fatigue due to more myoglobin

-glycotic fibers- use anaerobic glycolysis (fast twitch) bigger, lighter, and more fatigable

Question 6

3 types of muscle fibers (in order of recruitment)

Answer 6

1. slow oxidative fibers: good for endurance (fatigue resistant), slower ATPase so slower contraction, aerobic glycolysis, darker
2. fast oxidative fibers: fast contraction and ATPase, aerobic glycolysis, dark-medium, moderately fatigue resistant
3. fast glycolytic fibers: fast contraction and ATPase, anaerobic glycolysis, light, fatigable

Question 7

increase the load…

Answer 7

increase the latent period, decrease contraction and duration of contraction

Question 8

motor unit

Answer 8

more of them increase speed and duration of contraction

Question 9

aerobic exercise effects

Answer 9

(endurance exercise)
leads to increased…
-muscle capillaries
-# of mitochondria
-myoglobin synthesis
-greater endurance, strength
-can convert fast glycotic fibers into fast oxidative fibers

Question 10

effects of resistance exercise:

Answer 10

typically anaerobic
results in:
muscle hypertrophy (increased fiber size)
increased mitochondria, actin and myosin, glycogen stores and connective tissue

Question 11

the “overload” principle

Answer 11

forcing muscle to work hard is going to increase muscle strength, endurance, and gain

Question 12

“treppe”

Answer 12

warming up