Biomechanics Of Performance Flashcards
What are the three determinants of speed that are mentioned in Newton’s second law
Force mass acceleration , magnitude of net force, direction of force, mass of the object
Speed equals
Distance divided by time, the rate at which someone moves, stride length*stride frequency
Speed in sport is important for
get past defenders
Move into space
Catch up to attackers
Many high speed actions in sport
Sprint performance is
Acceleration
Maximum speed, stride length and stride frequency
Speed maintenance
Determinants of speed we can train
Athletes force production capacity
Ability to apply force in the horizontal plane
Mass of individual
Athletes force production capacity
An athletes motor potential is a large determinant of the horizontal component of the ground reaction force. Motor potential is determined by neural activation, leg spring stiffness, muscle fibre composition, anatomical join configuration, rate coding, detachment rates and muscle synergy, the neuromuscular systems ability to generate power has been shown to be correlated with sprint performance
Motor units peak force
Peak force produced by different fibre types is similar, but the rate at which they produce it is different, type II ARE FASTEST
Rate coding is
The amount of force a single motor unit can generate is dependent on the frequency at which it is stimulated by the cns and pns, greater force production when more signals sent
Determinants of Max force production
Increased motor unit recruitment
Lateral force transmission
Hypertrophy
Rate of force development
Plyometrics or ballistic training display a high level of rate coding, by sending more signals it counters the increase in detachment rate and thus improving strength at high velocities
Ability to apply force in the horizontal plane
Apply force to the ground and the is an equal and opposite force called the ground reaction force which propels us forward, the magnitude of the grf determines the speed of the individual, an athletes speed technique should be considered as their ability to orient their grf horizontally
Technical factors influencing ground reaction force
Triple extension
Ipsilateral shoulder and hip action
45 degree acceleration angle
Triple flexion
positive shin angle
Low heel recovery
Chest and eyes to the ground
Leg spring stiffness is
Dorsiflexion of the ankle at ground contact will allow for the storage of elastic energy
Sport speed is
Agility, change of direction due to a stimulus
Training agility
Sport specific
