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Task Specific Strength. Chapter 2. How, What and Why?. How to train What should be trained Why training should be performed What is strength? How is it achieved? Task specific strength has carryover. Elements of Strength. Maximal muscular performance 1RM or personal best
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Task Specific Strength Chapter 2
How, What and Why? • How to train • What should be trained • Why training should be performed • What is strength? • How is it achieved? • Task specific strength has carryover
Elements of Strength • Maximal muscular performance • 1RM or personal best • Pm, Fm & Vm • Parametric relation between these variables? • Negative relationships • Force/velocity relationship?
Nonparametric Relations • Maximum maximorum performance • Only max under favorable conditions • Pmm, Fmm & Vmm • Relation between Pm and Pmm is nonparametric • Nonparametric are positive
Nonparametric cont… • Greater Fmm and VmWHY? • Stronger and faster • Resistance must be sufficient to allow strength to be manifested • If force is low then strength plays no role • What sports? • Training should include both
Defining Strength • Ability to produce Fmm • Concentric – shortening against force • Eccentric – lengthening with force • Isometric – no change with force • Fmm must be against high force
Extrinsic Determining Factors • Mechanical feedback – effect of the outside forces • Force applied causes a change • Types of resistance • Elastic – force is pos related to distance of stretch • Inertia – F = MA • Hydrodynamic – viscosity • Compound resistance – weights and chains or elastic
Intrinsic Determining Factors • Rate of force development (RFD) – time for force to be manifested • Time to peak force Tm • Time to peak force is 0.3-0.4 s
Figure 2.8 • Explosive strength deficit 50% • Figure 2.8 • Finger snap (force accumulation)
Explosive Strength Deficit • May increase Fmm • May increase RFD with explosive work • Strength and power are different • S gradient on page28
Velocity • Inverse relationship • AV Hill equation on page 30 • Intermediate range is important • Max power is at 1/3 • why? (pg 31) • Shot putters vs. javelin throwers? • No relationship between Fmm and Vmm
Eccentrics • Much greater than concentric • Why? • Total force velocity curve • Fewer muscle fibers and EMG • DOMS and damage
Stretch-Shortening Cycle (SSC) • Eccentric-concentric couple • Countermovement jump • Elasticity – stretch induced – what formula? • Stiffness • Muscle – variable • Tendon – constant • Tension and stiffness are related
Neural Mechanisms • Muscle spindles – stretch • Golgi tendons – force • Neural loop – reflex • Training enhances this effect
Strength Curves • Strength changes as a function of ROM • Why is this important for lifting? • Overlap? • Length tension curves • Torque=fd (d=moment arm) • Lever changes and force changes
Levers and Strength • Strength = force moment arm ratio • Short levers create more force • Line of force action is close to joint when force is high
Parametric relations are negative Nonparametric may be positive Max force equals strength External factors such as type of resistance Time of force production RFD is important (isometric) Strength and power are different Concentric vs. eccentric strength SSC reactive strength Elastic and neural Spindles vs. golgi Length tension Lever length Summary
Next Class • Lab tonight on VJ force, velocity and jump height (CMJ vs SJ) and unloaded knee extension velocity (R vs L) • Homework explanation • Read Huxley article and write synopsis • Next week Chapter 3 and lab