1. Types of Muscles Smooth w Involuntary muscle; controlled unconsciously
w In the walls of blood vessels and internal organs
Cardiac
w Controls itself with help from nervous and endocrine systems
w Only in the heart
Skeletal
w Voluntary muscle; controlled consciously
w Over 600 throughout the body

2. SKELETAL MUSCLE STRUCTURE

4. KEY POINTS w An individual muscle cell is called a muscle fiber.
w A muscle fiber is enclosed by a plasma membrane called the sarcolemma.
w The cytoplasm of a muscle fiber is called a sarcoplasm.
w Within the sarcoplasm, the T tubules allow transport of substances throughout the muscle fiber and the sarcoplasmic reticulum stores calcium.

7. AN ACTIN FILAMENT

8. The Myofibril
w Myofibrils are made up of sarcomeres, the smallest functional units of a muscle.
w A sarcomere is composed of filaments of two proteins, myosin and actin, which are responsible for muscle contraction.
w Myosin is a thick filament with a globular head at one end.
w An actin filament—composed of actin, tropomyosin, and troponin—is attached to a Z disk.

9. Events Leading to Muscle Fiber Action
A motor neuron releases acetylcholine (ACh).
2. ACh binds to receptors on the sarcolemma.
3. The action potential triggers release of Ca2+.
4. The Ca2+ binds to troponin on the actin filament, and the troponin pulls tropomyosin off the active sites, allowing myosin heads to attach to the actin filament.

12. Resting Membrane Potential (RMP
-Difference between the electrical charges inside and outside a cell, caused by separation of charges across a membrane
-High concentration of K+ inside the neuron and Na+ outside the neuron
w K+ ions can move freely, even outside the cell to help maintain imbalance
w Sodium-potassium pump actively transports K+ and Na+ ions to maintain imbalance
w The constant imbalance keeps the RMP at –70mV
Action potentials—rapid, substantial depolarization of the membrane (–70 mV to +30 mV to –70 mV all in 1 ms)

13. RESTING STATE

17. GOLGI TENDON ORGAN

18. Slow-Twitch (ST) Muscle Fibers
High aerobic (oxidative) capacity and fatigue resistance
Slow contractile speed (110 ms) and myosin ATPase
10–180 fibers per motor neuron
Low sarcoplasmic reticulum development

19. Fast-Twitch (FTb) Muscle Fibers
Fast contractile speed (50 ms) and myosin ATPase
300–800 fibers per motor neuron
High sarcoplasmic reticulum development
The difference in force development between FT and ST motor units is due to the number of muscle fibers per motor unit, not the force generated by each fiber.

20. Fast-Twitch (FTa) Muscle Fibers
Intermediate Muscle Fibers –
Specificity of Training is the key.
Will mimic other fibers

21. A history of Anabolic Steroids
1889 Mr. Se’quard
1920’s Dr. Koch
1960’s Dr. Ziegler
1970’s Olympic Committee
1980’s NCAA Urine testing

22. Side Effects of Anabolic Steroids
Cycling
Stacking
Androgenic, Anabolic
Side Effects of Anabolic Steroids
Gynecomastia
Acromegaly
Liver Disease
Hirsutism
Testicular Atrophy
Acne
Roid Rage

23. Supplements
Creatine
Androstenedione
Ergogenic Aids

24. Functional Classification of Muscles
Agonists—prime movers; responsible for the movement
Antagonists—oppose the agonists to prevent overstretching of them
Synergists—assist the agonists and sometimes fine-tune the direction of movement

26. Key Points
Resistance training programs can produce a 25% to 100% improvement in strength within 3 to 6 months.
Transient Hypertrophy—pumping up of muscle during a single exercise bout due to fluid accumulation from the blood plasma into the interstitial spaces of the muscle.
Chronic Hypertrophy—increase of muscle size after long-term resistance training due to changes in muscle fiber number (fiber hyperplasia) or muscle fiber size (fiber hypertrophy).
Muscle protein synthesis increases during the post exercise period.

28. Delayed-Onset Muscle Soreness (DOMS)
Results primarily from eccentric action
Is associated with damage or injury within muscle
w May be caused by inflammatory reaction inside damaged muscles
w May be due to edema (accumulation of fluid) I inside muscle compartment
w Is felt 12 to 48 hours after a strenuous bout of exercise (Glycogen Synthesis Impaired)

29. Linear – Same exercises day in and day out
Strength—few reps and high resistance (6-RM)
Muscular endurance—many reps and low resistance (20-RM)
Power—several sets of few reps and moderate resistance; emphasize speed of movement
Muscle size—more than 3 sets of 6-RM to 12-RM loads; short rest periods
Linear – Same exercises day in and day out
Non-Linear – Changing the exercise routine on a daily basis

30. Study Questions When will your body synthesize proteins?
Chronic Hypertrophy vs. Transient
Difference in strength and endurance program
Efferent and Afferent
Sensory organs (muscle spindles and Golgi)
All terminology associated with a nerve cell(dendrites, cell body, hillock, axon, nodes, Myelin sheath

31. Study Questions
Know the resting voltage within a nerve and when it fires
Chemicals released at the terminal end of nerve
Sarcomere-Motor Unit-Calcium-Magnesium-Fine motor vs. Gross motor, Bands and Zones (Pg 320)
Isometric, Isotonic, Isokinetic
Eccentric, Concentric

32. Study Questions Initial strength gains (Engrams)
Muscle Fiber types (I, IIa, IIb)
Look at the True/False and Multiple Choice questions from chapter 12 & 15
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Interval Training, Circuit Training, Plyometrics