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TRACK AND FIELD SPRINTING. Drive phase or (the start). What is sprinting . Sprinting, in athletics ( track and field ), is a footrace over's a short distance with an all-out or nearly all-out burst of speed. . SPRINT EVENTS FOR. INDOOR. OUTDOOR. 60 meters 200 meters 400 meters - PowerPoint PPT Presentation
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TRACK AND FIELDSPRINTING
Drive phase or (the start)
What is sprinting Sprinting, in athletics (track and field), is a
footrace over's a short distance with an all-out or nearly all-out burst of speed.
SPRINT EVENTS FORINDOOR OUTDOOR60 meters 200 meters400 meters55m hurdles60m hurdles
100m200m 400m4x100m relay110 hurdles for men100 hurdles for
women
Phases of the sprinting
Drive phase or (the start)Acceleration phaseTransition phaseMaximum VelocitySpeed Maintenance
Acceleration phase in terms of the drive phase
The objective of this phase is to leave the blocks and to prepare for the first stride.
Points for an effective drive phase
Drive the back leg forward keeping the heel low until the shin is approx 45° to the ground and then drive the foot down hitting the ground just behind the body's centre of mass
Over the next 7-8 strides (approx. 10 metres) angle the shin of the front leg, before it is driven down, will increase by 6-7 stride so that by the 7-8 stride the shin is vertical to the ground.
Over the first 7-8 strides the whole body angle will increase from 45° to approx. 30° degrees - approx
Points for an effective drive phase
Eyes focused on the track to keep low to allow the build up of
speed
Forward lean of the whole body with a straight line through the
head, spine and extended rear leg
Shoulders held back and relaxed, square in the lane at all times
Arms move with a smooth forward backward action - not across the
body - drive back with elbows - hands move from approx. shoulder
height to hips
Points for an effective drive phase (cont)
Elbows maintained at 90 degrees
fully extended rear leg pushing off the track with the toes - drive
the leg forward with a high knee action with the knee pointing
forward On the ball of foot/toes at all times - feet pointing
forward straight down the lane
The drive is maintained for first 20-30 metres (approx.16-17
strides) at the end of which the body is tall with a slight forward
lean
Biomechanics of the legs Leaving the Blocks
The aim of starting biomechanics is the development of
maximum horizontal velocity and this is achieved by placing
the body in the best biomechanical position to apply force.
Asafa_Powell_Block_Start.mp4
The biomechanical concepts
Pushing behind centre of mass causes forward rotation around
centre of mass.
Forward rotation created by push off leg and the rear arm.
Forward rotation counterbalance by free swing led and front
arm.
Lower heel recovery during drive phase reduces time to
recover leg. This is achieved by the “piston” action with the leg
and also by sweeping the toe across the ground
The End