1. Muscle Physiology

2. Muscles are AMAZING! Incredibly sophisticated Fuel efficient
Long lasting
Self-healing
Grow stronger with practice
They do EVERYTHING from walking
to keeping your blood flowing!

3. What do muscles do? Movement of skeleton Body functions Expression
Speaking, singing, facial expressions, writing, dancing, fighting, etc…

4. Muscle Issues Sprain or Strain? Cramps? What’s happening?
How to prevent?

5. Muscle Sprain vs. Strain
Sprain = injury to the ligament
Strain = injury to the muscle or tendon

8. Cramps!

9. Causes?
Heat
Heavy exercises
Dehydration
Some medicines

10. Prevention?

11. Muscle Contraction Physiology Animations
Mechanics of muscle contraction
Function of neuromuscular junction
Contraction and nerve impulse
Sacromere contraction
Sliding Filament Theory

12. Oxygen supply & Cell Respiration
Hemoglobin
is bonding site for O2 in blood
Gives blood red color
Myoglobin
Gives muscle color
Is a bonding site for O2 in muscles
Temporarily stores O2 in muscles

13. Oxygen debt Aerobic respiration Anaerobic respiration O2 needs are met
Produces 34 ATP molecules/glucose
Low lactic acid
Anaerobic respiration
Need more O2 than you have
Pyruvic acid made during glycolysis breaks into lactic acid
Low ATP (2 ATP molecules/glucose)

14. What happens to the lactic acid?
Enters blood stream
Moves to liver
Makes glucose from lactic acid
this requires ATP and O2
Muscles also need to replenish ATP
SLOW PROCESS = OXYGEN DEBT
Results= sore muscles!

15. Muscle Fatigue Exercise to strenuous for too long Rigor Mortis
Ca2+ ions increase (contraction)
Decrease of ATP (no relaxation)
Lasts about 72 hours post mortem

16. Muscle Response Threshold stimulus All-or-none response
Minimum stimulation needs for an isolated muscle fiber to contract
These can vary!
All-or-none response
Skeletal muscle either contracts or not
NO PARTIAL

18. Muscle contraction Twitch A single contraction
Fraction of a second in length

19. Types of twitch Slow Fast Fatigue resistant (oxidative) Lots of O2
More mitochondria
Better capillary network
Fast
Fatigue easily (glycolytic)
More filaments = wider muscles
It’s all about fatigue!

20. Muscle contraction Summation Tetanic contraction
Series of stimulus of increasing intensity
Contraction of muscle builds then relaxes
Tetanic contraction
Contraction severe
Builds in intensity
Does not relax!
Just relax!
I can’t!

21. Muscle contractions Sustained contractions Whole muscle contractions
Allow our movements
Muscle fibers are always under sustained contractions
MUSCLE TONE
NO muscle tone = collapse