☰ Chapter 11: Muscle Mechanics

• Describe the effect of fiber direction, cross-sectional area, and fiber length on muscle force
• Distinguish between the various types of muscle fiber for endurance and speed
• Describe the three types of muscle activations
• Calculate stress and strain for muscles

What is strength (Bench Press)?

T = F⊥d

• Cross-sectional Area
• Muscle Design

  Figure 2a: Fusiform fiber arrangement (Example-Biceps brachii), 2b: Unipennate fiber arrangement (Example-Extensor digitorum longus of the hand), 2c: Bipennate fiber arrangement (Example-Rectus femoris).

• Myofibril Organization
• Fiber Length
• Contraction Velocity
• Fiber Type
  • (1) slow twitch fatigue resistant (I), (2) fast twitch fatigue resistant (IIa), (3) faster twitch fatigue resistant (IIx), and (4) fastest twitch fast fatigue (IIb).
• Neuromuscular Factors
  
  

Tendons and Ligaments

• 70% water
• 25% collagen
• 5% elastin
• Traces of inorganic components