Lecture 7 - Athlete Specific Strength

What are peripheral factors of strength?

• affect the max force capability of individual muscles —> muscle hypertrophy

  • filaments per myofibril

  • myofibril per muscle fiber

  • fiber number

  • fiber cross-sectional area

What are central factors of strength?

• affect coordination of muscle activity by the central nervous system

  • Intramuscular coordination: the ability to recruit motor neurons in one muscle

  • Intermuscular coordination: the ability to recruit motor neurons in multiple muscles

How does muscle hypertrophy relate to peripheral factors?

• myofibrillar hypertrophy = power lifters

  • an increase in the size and density of the muscle fibers leading to an increase in strength and power

• sarcoplasmic hypertrophy = body builders

  • the increase in muscle cell volume (not fully supported to be true)

Absolute strength

the maximum force a muscle/muscle group can produce

• sports where the main resistance is external forces (shot put, power lifting)

Relative strength

the maximum force a muscle/muscle group can produce relative to bodyweight

• sports where the main resistance is moving their own bodyweight (gymnastics, olympic lifting)

How does intramuscular coordination work?

• recruits motor units from small to large: I —> IIA —> IIX

• isolation workout movements mainly improve this

How does intermuscular coordination work?

• is the technique of properly recruiting lots of motor neurons

• compound workout movements improve this

• ideal for sport performance increase because sports requires the coordination of many muscle groups

How is muscle force of intramuscular coordination increased?

Increasing motor unit recruitment = common in larger muscles (lift more weight to improve)

Increasing motor unit firing frequency = common in smaller muscles