A one year plan - physiotherapeutic clinical reasoning, considerations of biomechnics, in rehabilitation

Training volume

Training progression

Training factors/considerations

Biomechanics - velocity in training regimes

Power = force x velocity       Work = force x time = force x displacement

• therefore, you can use speed (min weight) to create power

Momentum = mass x velocity

• inertia dictates that a body will stay at rest or uniform motion

Moment of Inertia (of a spinning person) = mass x (radius squared)

• energy is always conserved, hence, as the person brings their arms to their side, their angular and linear velocities will increase (since the mass is constant)

Impulse = force x time (change of momentum) = mass x velocity - mass x initial velocity

• therefore, 'timing' is important for training stability and co-ordination

Kinetic Energy = 1/2 mass x velocity squared = Potential energy = mass x gravity x height

• height can be used to increase potential energy which in turn can create increases in velocity
• alternatively, velocity may be used to create potential energy
• additionally, increases in weight whilst maintaining constant velocity, increases kinetic energy

Newtons Third Law : "for every action there is an equal and opposite reaction"

• therefore poor technique will result in an equal and opposite reaction in the plane of motion eg. whilst swimming freestyle and stroking too wide will result in an equal and opposite compensatory motion in the leg
• elevation of the right arm will result in equal and but opposite vector creation on the contralateral side of the body in order to maintain stability 
• read a good book

Orthotics and Biomechanics of Gait

kinematics of cycling

Last update : 22 July 2006