1. 1. In muscular physiology, what is meant by a "twitch?"
QOD- 3/28/17
Review
1. In muscular physiology, what is meant by a "twitch?"
2. What is meant when a muscle is in complete tetanus?
3. I am contracting a muscle, but it is not getting any shorter. What type of contraction is this?

2. QOD- 3/28/17
1. In muscular physiology, what is meant by a "twitch?"
2. What is meant when a muscle is in complete tetanus?
3. I am contracting a muscle, but it is not getting any shorter. What type of contraction is this?
single stimulus-contraction-relaxation sequence
smooth sustained contraction
isometric

3. ENERGY USE 

AND 

MUSCULAR 

ACTIVITY
Preview
Outline #3 QOD
1. What are the 3 main 

energy sources for muscle contraction?
2. Which is more efficient, anaerobic or aerobic pathways?
3. T/F- muscle fibers are either fast twitch or slow twitch.

4. ENERGY USE 

AND 

MUSCULAR 

ACTIVITY
Outline #3 QOD
1. What are the 3 main 

energy sources for muscle contraction?
2. Which is more efficient, anaerobic or aerobic pathways?
3. T/F- muscle fibers are either fast twitch or slow twitch.
ATP, CP, Glycogen

5. What are the energy sources for skeletal muscle fibers
What are the energy sources for skeletal muscle fibers? How abundant are they? How long do they last?

6. What energy supplies are used in resting skeletal muscle?
Fig in text
Generates 95% of muscle needs at rest

7. What happens as activity increases?

8. How does this change as energy demands are greater than mitochondrial activity can handle?

9. Compare energy use over time at peak work.

10. What stored energies are rebuilt when paying “oxygen debt”?

12. In terms of muscle contraction, what is force? What is endurance?
MUSCLE PERFORMANCE
Power/tension(max) Endurance/time(max)
 Depends on: 1. type of muscle fibers
 2. physical conditioning/training

14. If you are “born” a sprinter, can you change your muscle fibers to run marathons?

15. What is this graph telling you about male vs
What is this graph telling you about male vs. female when it comes to muscle mass?

16. What is the role of Satellite cells with exercise
What is the role of Satellite cells with exercise? How do muscle cells repair themselves?

17. HYPERTROPHY
ATROPHY- after 

cast 6 weeks

18. Why does muscle repair decrease with age?

20. Quick Check Questions: Answer with your group
Why would a sprinter experience muscle fatigue before a 
marathon runner would?
2.Which activity would be more likely to create an oxygen debt in an individual who regularly exercises: swimming laps or lifting heavy weights?
3. Which type of muscle fibers would you expect to 
predominate in the large leg muscles of someone who excels at endurance activities such as cycling or long-distance running?

21. Quick Check Questions: Answer with your group
Why would a sprinter experience muscle fatigue before a marathon runner would?
Which activity would be more likely to create an oxygen 
debt in an individual who regularly exercises: swimming 
laps or lifting weights?
Which type of muscle fibers would you expect to 
predominate in the large leg muscles of someone who 
excels at endurance activities such as cycling or long-
distance running?
the sprinter blows through reserves fast, cannot produce enough ATP aerobically for the intensity of effort
Lifting weights, again, doing powerful movements, needs a 
lot of ATP, utilizes stored energy faster
Slow twitch fibers- can contract for long periods of time 
without fatiguing