2. Biomechanics of resistance exercise Flashcards
Origin and insertion
Origin is proximal
Insertion is distal
or it depend on which point is pivot and which is moving
Muscles could be related to movement..
Agonist prime mover
Antagonist slower or stopper
Synergist if assist
First class lever
A lever for which the force and resistance act on opposite site of fulcrum. The mechanical advantage depend by the ratio between the two forces. Maf/Mrf
>1 advantage
Second class lever
Fulcrum.Fr.Fm
always an advantage lever
Triceps brachii or Calf muscles
Third class lever
Fulcrum.Fm.Fr
always a disadvantage lever
Biceps brachii
Force tends to rotate object
Torque or moment
Most of the rotate limb on joint are lever class
three, in disadvantage
but it change during real word activities, frame by frame
Tendon insert farther as variation, involve..
A better moment in the movement, but with less speed production
Force (N)
Mass (kg) x accelleration (9.8m/s2)
Work (J)
Force (N) x Displacement (m)
Torque x Angular displacement
Power (W)
Work (J) / Time (s)
Force (N) x Velocity (m/s)
Difference strength and power
Strength is the capacity to exert force at any speed
Power is the mathematical product of force and velocity at whatever speed
Neural control main components for strength
Recruitment of MU
Size of MU recruited
Firing rates of impulse
Regarding strength exert, is more important CSA or volume ?
CSA more then volume
High pinnation angle it means on performance
More fiber in parallel, higher CSA, more strength, but less velocity power production, capacity related to fibers in series.
Concentric action
Eccentric action
Isometric action
CA - contractile force > resistive force
EA - contractile force < resistive force
IA - contractile force - resistive force
Strength to mass ratio
athletes ability to accelerate his body
Inertia of weight
when accelerated it exert inertial force on the athlete
Bracketing technique
10% more or less of weight to a variation of training
Fluid resistance
force encountered by an object moving through a fluid
Back muscle lever typology
great disadvantage
S shape, kyphotic slightly rounded
Fluid ball
Abdominal fluids and tissue kept under pressure by muscles as abdominal and diaphragm
