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Muscle Physiology 1
Muscle Physiology 2
Muscle Physiology 3
Fatigue 1
Fatigue 2
100

What are the 3 types of muscle fibres, name the whole name and thei short for representation like (Type__) 

Slow Twitch - Type 1

Fast Oxidative Glycolytic  - Type IIA

Fast Glycolytic - Type IIX

100

What are satellite cells?

  • Undifferentiated cells

  • Play an important role in muscle growth and repair

  • Training (i.e resistance TR) activates them initiating a divide

100

Why do we not recruit 100% of our muscle fibers?

Because it will result in damage to muscles and tendons leading the muscles separating from the bone

100

What is muscle fatugue?

a reduction in muscle power output that results from decreased muscle force generation and shortening velocity

100

What are the other metabolites involved in peripheral fatigue? 

Potassium

High Na+/K+ pUMP

200
What influences fibre type distribution? (3 FACTORS)


Genetics

Hormone Concentrations

Exercise Habits

200

How are skeletal muscle fibres typed?

Muscle Biopsy - Small piece of muscle is removed

Staining for type of myosin ATPase isoform

- immunohistochemical staining

- gel electrophoresis 

200

What is the length tension relationship - HINT 3 factors persay

  • Less than optimal length

    • Fewer cross-bridge interactions = reduced tension development

  • Optimal length

    • Max cross-bridge interaction= maximal tension development

  • Greater than optimal length

    • No cross bridge interaction = no tension

200

What are some causes of muscle fatigue? Hint they all have model in them

CV System Model

Energy Supply Model

Neuromuscular Model

Thermoregulatory Model

Biomechanical Model

Psychological Model

Central Governor Model

300

Answer the following questions.

What muscle fibers would a marathon runner have mostly? What muscle fibers would a sprinter have? What split of muscle fibers would an average population have

1. Slow

2. Fast

3.50/50

300

What is a force velocity relationship and power velocity relationship?

FVR

Fast fibers function at greater velocities than slow fibers and they produce more force than slow-twitch fibers at a given velocity

PVR

  • Power for fast twitch fibers is higher at each velocity

  • Power drops off significantly at 300 degrees/second in slow twitch fibers

  • Power is force and velocity together

300

Name the characteristics of motor units


  • Fast twitch or slow twitch

  • High force or moderate force or low force

  • Fast fatigue or fatigue resistant 

300

Name the 2 types of muscle fatigue? 

Central and Peripheral

400

There are 3 factors that contribute to BioChemical Properties, what are they and what do they do? 

  1.  Oxidative capacity

  2.  Type of myosin ATPase isoform

  3. Abundance of contractile protein in muscle fibre

400

What is the pathways for the Neuromuscular Junction NMJ

  • Action potential comes from nervous system

  • No physical contact with muscle

  • AP stimulates release of ACh

    • ACh travels across the cleft to open NA+ channels

  • Generates an end-plate potential that is enough to continue AP

  • AP travel along muscle fiber membrane down T-tubules

400

What is the sliding filament theory and what were to happen if we performed an isometric contraction? 

  • Isometric= between

    • No movement

      • 1. No sliding

      • 2. No advantages of ECC

      • 3. No disadvantages of CON

400

What are the 3 things that contribute to fatigue?

  • Phosphocreatine depletion (wingate)

  • Lack of ATP and buildup up of ADP, affects peripheral fatigue

  • High glycolytic fatigue, that may contribute to central fatigue

  • Slow down the function of enzymes it slows down the rate of ATP

500

What are the 4 Contractile Property factors? Name at least one factor for each of as much info as possible :)

1. Maximal force production

2. Speed of contraction (Vmax) (max velocity)

3. Maximal power output

4. Muscle fibre efficiency

500

What are the 4 steps to force regulation?

Types and number of motor units recruited

Initial muscle Length

Nature of the Neural Stimulation of Motor Units

Contractile History of the muscle 

500

What happens to both concentric and eccentric movements during exercise, and which are the weakest and strongest?

  • Concentric = weakest

    • ATP required to shorten

      • 1. Taking up series elastic component

      • 2. Cross-bridge braking effect

      • 3. Sliding filament effect

        • Actin slides in same direction as power stroke

      • Must overcome load

  • Eccentric = strongest

    • 1. Braking effect that hindered concentric helps eccentric

    • 2. Passive resistance to stretch

      • Crossbridges stretch while bound to actin

      • This resistive force is added to cross bridges

    • You are resisting the load