Lecture on Central Nervous System and Training

Introduction

• Sponsored by Squarespace
• Focus on how the central nervous system (CNS) controls muscle and strength
• Training is not just about muscles but the CNS

Central Nervous System Basics

• CNS includes the brain and spinal cord
• Responsible for thoughts, memories, personality, and movement signals
• Signals processed in CNS are sent to peripheral nervous system for movement

Muscle Fibers

• Muscles consist of thousands of muscle fibers
• Muscle fibers contain myofilaments made of actin and myosin
• Muscle contraction occurs by sliding of actin and myosin

Motor Cortex and Movement

• Primary motor cortex in the brain controls movement
• Neurons in motor cortex map to specific body areas (motor homunculus)
• Movement initiated by electrical impulses (action potentials)

Motor Units

• Motor units consist of muscle fibers innervated by a single motor neuron
• Muscle fibers in motor units are either type 1 (slower) or type 2 (fast)
• Motor units recruited based on signal strength (Henneman's size principle)

Neural Drive and Rate Coding

• Rate coding: frequency of impulses affecting motor neuron activation
• Trained athletes can recruit more motor units than untrained individuals

Brain Plasticity

• Brain adapts (plasticity) with training, e.g., larger motor cortex areas in musicians/athletes
• Muscle control training can increase gray matter and cortical thickness

Skill Acquisition and Motor Patterns

• Skills are learned in the brain, specifically in the motor cortex
• Repeated actions form strong neural pathways
• Motor patterns involve primary motor cortex, premotor cortex, basal ganglia, cerebellum

Intramuscular and Intermuscular Coordination

• Intramuscular: recruiting more of a single muscle
• Intermuscular: coordination of multiple muscles and external stimuli

Training the CNS

• Train CNS by lifting heavy/explosively (80-95% of 1RM)
• Overcoming isometrics: pushing/pulling against immovable objects to train maximum neural drive
• Bodybuilders focus on endurance, powerlifters on strength

Greasing the Groove

• Practice movements repeatedly with low fatigue
• Spaced learning: practice skills at intervals throughout the day

Variation and Movement Patterns

• Introduce variation in training to build robust movement patterns
• Train under different stimuli and conditions

CNS Recovery

• Overtraining can lead to CNS fatigue, but it’s more about stress and recovery than actual CNS damage
• Recovery involves managing stress and allowing time for body resets

Improving CNS Resilience

• Military training and stress inoculation improve resilience to exertion and stress
• Psychomotor vigilance training can improve focus under stress

Conclusion

• Training CNS can enhance strength, coordination, and movement efficiency
• Strength is a skill; practice can unlock latent power and performance
• Encouragement to incorporate CNS-focused training into workout routines