Henneman's size principle: MUs are recruited in order of their size, from small to large
Relative contributions of rate coding and spatial recruitment.
Small muscles - all MUs recruited at approximately 50% max. force; thereafter, rate coding is responsible for force increase up to max
Large muscles - all MUs recruited at approximately 80% max. force.
4. Velocity of shortening: Force inversely related to shortening velocity The force-velocity relationship for muscle tissue: When resistance (force) is negligible, muscle contracts with maximal velocity. Velocity Force (Low resistance, high contraction velocity)
The force-velocity relationship for muscle tissue: As the load increases, concentric contraction velocity slows to zero at isometric maximum. Velocity Force isometric maximum
Force-Velocity Relationship in different muscle fiber types Type II fiber Type I fiber
Effect of Temperature on Force-Velocity relationship (22 o C, 25 o C, 31C o , and 37 o C)
Force -Velocity Relationship (Effect of strength-Training)
Force-velocity Relationship During Eccentric Muscular Contractions
Force/Velocity/Power Relationship Force Velocity Power 30% 30% Force/velocity curve Power/velocity curve From Basic Biomechanics by Susan Hall (3rd edition), Fig 6.25, page 175
Effect of Muscle Fiber Types on Power-Velocity Relationship
Consequences of the force-velocity relationship for sports practice
When training for sports that require power, train with the appropriate % of 1 RM that will elicit the most power.
24 weeks of:
a). heavy weight-training b. Explosive strength training
From Science and Practice of Strength Training (2 nd edition) V.M. Zatsiorsky and W.J. Kraemer (2006) Fig 2.19 P. 39)