生物力学入门

Introduction

• Biomechanics studies the structure and function of biological systems using mechanical principles.
• It applies physics to understand movement, forces, and energy transfer in living organisms (humans, animals, and plants).
• This allows analysis of performance, injury prevention, and rehabilitation.

Key Concepts in Biomechanics

• Force: A push or pull that causes or alters motion (measured in Newtons). Examples include muscular forces, gravitational forces, and contact forces.
• Motion: Change in position over time; described by displacement, velocity, and acceleration.
• Energy: Capacity to do work. Types include kinetic (motion), potential (stored), and chemical (stored in bonds). How energy is converted and used during movement is crucial.
• Torque: Rotational force (measured in Newton-meters). Understanding joint movement is key.
• Kinematics: Study of motion without considering forces, including displacement, velocity, and acceleration.
• Kinetics: Study of forces responsible for motion.
• Mechanical Advantage: Ratio of output force to input force, measuring force multiplication. Important for joints, muscles, and limbs.

Applications of Biomechanics

• Sports Performance Analysis: Improves technique, identifies weaknesses, tailors training programs by analyzing movement patterns, force production, and energy expenditure. Tools like video analysis, motion capture, and force plates are used.
• Injury Prevention: Identifies injury risk factors and develops strategies to reduce risk by understanding how forces impact the body.
• Rehabilitation: Designs and evaluates rehabilitation programs to improve joint function, muscle strength, and coordination for injury recovery.
• Prosthetics and Orthotics: Designs artificial limbs and supportive devices to improve function and reduce disability, considering human movement forces.
• Ergonomics: Designs and evaluates workplaces and tasks to maximize productivity, minimize discomfort, and prevent injury by considering worker-environment interaction and tools.
• Clinical Gait Analysis: Assesses and evaluates human walking patterns to detect gait mechanics abnormalities.
• Animal Locomotion: Studies animal movement and efficient movement mechanisms.

Biomechanics Tools and Techniques

• Video Analysis: Records and analyzes movements frame by frame.
• Motion Capture Systems: Tracks joint and body segment positions in 3D space with markers.
• Force Plates: Measures forces produced by contact with surfaces.
• Electromyography (EMG): Measures muscle electrical activity during movement.
• Computer Modelling: Creates simulations of human movement to analyze forces and torques.
• Simulation: Uses biomechanical principles to simulate human movement, predict potential risks of different movements and activities.
• Experimental Designs: Develops experimental procedures to test hypotheses, collect data, and support theories.

Factors Affecting Biomechanical Analysis

• Individual Differences: Age, sex, height, weight, fitness, and health conditions impact results.
• Environmental Conditions: Temperature, humidity, and terrain affect performance and injury risk.
• Task-Specific Factors: Specific tasks, equipment, and environment influence the biomechanical analysis.

Conclusion

• Biomechanics applies mechanical principles to study living organisms, focusing on the interaction of forces and movements.
• It includes numerous applications and tools.
• Understanding biomechanics improves human performance, prevents injuries, and enhances rehabilitation.