OUTLINE - MUSCLE MECHANICS

 

I. Single Joint Muscle Model

A. Axis

B. Muscle Force

C. Resistance Force

II. Roles of Muscle Force

A. Stabilizing

B. Rotary

III. Torque

A. Axis

B. Force

1. Point of Application

2. Line of Action

C. Moment Arm

D. Equation

1. Torque = Moment Arm x Force

IV. Single Joint Muscle Model - Revisited

A. Axis

B. Muscle Torque

1. Muscle Moment Arm

2. Muscle Force

D. Torque created by the stabilizing component of the muscle force

E. Torque created by the rotary component of the muscle force

V. Rotation of a Segment

A. Net effect (torque)

B. Muscle Torque

C. Resistance Torque

1. Resistance Moment Arm

2. Resistance Force

VI. Muscular Actions - Revisited

A. Isometric

B. Concentric

C. Eccentric

VII. Angle of Pull

A. Relationship with the Muscle Moment Arm

VIII. Resistance Training

A. Dynamic versus Variable Resistance

B. Free weight versus Pulley systems

IX. Directional Nature of Torques

X. Levers

A. Components

1. Axis

2. Motive Torque

a. Moment Arm

b. Force

3. Resistive Torque

a. Moment Arm

b. Force

B. Mechanical Advantage

C. Classes

1. First

2. Second

3. Third

XI. Pulleys

XII. Summary

 

MUSCLE TORQUE

(TM = MAM x FM)

 

I. Muscle Moment Arm

A. Anatomical Structure

B. Joint Angle

II. Muscle Tension/Force

A. Excitation Factors

1. Recruitment

2. Discharge Rate - Rate Coding

3. Discharge Pattern

B. Muscle Structure

1. Muscle Size

a. Total # of fibers

b. Number of Motor Units

1. Size (Innervation Ratio) of each motor unit

2. Muscle Types

a. Fiber Types

1. FG/IIb

2. FOG/IIa

3. SO/I

b. Motor Unit Types

1. FF

2. FR

3. S

3. Muscle Architecture

a. Pennate

b. Non-pennate

C. Muscle Mechanics

1. Length/Tension relationship

2. Force/Velocity relationship

3. Prestretch or Stretch/Shortening phenomenon

D. Resistance Training can increase the capacity of the muscle to generate tension