Muscle Physiology

Muscle physiology is the scientific study of the function of muscles, examining how they contract to produce force and movement. It delves into the molecular mechanisms of this process, primarily the sliding filament theory, where actin and myosin filaments interact following a nerve impulse at the neuromuscular junction. This field explores the entire sequence of events, from the electrical signal (action potential) that triggers the release of calcium ions—a process known as excitation-contraction coupling—to the metabolic pathways that supply the necessary energy (ATP) for sustained activity and the factors contributing to muscle fatigue. Furthermore, it investigates how the nervous system controls muscle force through the recruitment of motor units and how different muscle fiber types are specialized for tasks requiring either endurance or power.

1. Introduction to Muscle Tissue
   1. Overview of Muscle Tissue
      1. Definition of Muscle Tissue
      2. Historical Perspectives on Muscle Study
   2. General Functions of Muscle
      1. Producing Body Movements
         1. Locomotion
         2. Manipulation of Objects
         3. Facial Expressions
      2. Stabilizing Body Positions
         1. Postural Control
         2. Joint Stabilization
      3. Storing and Moving Substances
         1. Sphincter Control
         2. Peristalsis
         3. Blood Flow Regulation
      4. Generating Heat
         1. Shivering Thermogenesis
         2. Non-shivering Thermogenesis
         3. Basal Muscle Tone and Heat Production
   3. Properties of Muscular Tissue
      1. Electrical Excitability
         1. Resting Membrane Potential
         2. Action Potential Generation
         3. Ion Channel Function
      2. Contractility
         1. Force Generation Mechanisms
         2. Shortening and Tension Development
         3. Active Force Production
      3. Extensibility
         1. Stretching Beyond Resting Length
         2. Limits of Extensibility
         3. Passive Tension Development
      4. Elasticity
         1. Return to Original Length
         2. Elastic Recoil Properties
         3. Role in Muscle Function
   4. Types of Muscle Tissue
      1. Skeletal Muscle
         1. Voluntary Control
         2. Striated Appearance
         3. Multinucleated Structure
      2. Cardiac Muscle
         1. Involuntary Control
         2. Striated and Branched Structure
         3. Single Nucleus per Cell
      3. Smooth Muscle
         1. Involuntary Control
         2. Non-striated Appearance
         3. Single Nucleus per Cell