JAN ŽELEZNÝ -THROW ANALYSES

The Approach and throw
Železný in most of his throws shows good characterislics of rhythm and balance, reaching an adequate speed.  An intelligent approach of runup means easier transition and plant. Bouncing running with high knees and increase speed by the frequency.  With his easy, relaxation and low mass-center, Jan promotes an easy and quick transition to the throw, thos his leg support.  He uses left arm for the lead balance along the throw.  He starts to withdraw when the right foot is planted and brings the javelin back into good positions.  He maintains his high knees by steady cross-over steps.

During the last stride Železný keeps his left shoulder in the the direction of the throw until the left foot is planted. The acceleration of the right hip begins during the last stride and increases dramatically when the left foot is planted. The right arm stays relatively extended. This allows Železný to adopt a good ‘C position’, which is very important. The strike with the right arm follows and the right elbow moves forward/upward.
The position of Železný’s right elbow is relatively low in comparison wilh the position
generally recommended by coaches.  Rotation of the right leg with the knee down and for freeing the front right hip for full rotation forcing the left leg go down and advance forward in the trunk.  The left arm opens the chest, but without pulling back the left shoulder.

The left side is blocked firmly. Left shoulder keeps pressure while hip drive before plant and block. Left arm working but shoulder stay there to last moment. Right leg keep pushing hip and left foot forward to the ground. Body stretching and storing energy!

Železný executes his throws (left foot) relatively close to the foul line.  The block of a good throw, is when  the javelin is released after the time of planting the left foot.  The good left foot alignment force-javelin direction is key in the release.  To pul all the power into the intended flight direction of the javelin is extremely difficult. His angle of release and of attack is 40-42% average.

Jan’s right leg keep pushing hip and left foot forward to the ground, he  waits until the left leg hits to finalize the hip. In order to have this type of ability, the thought process needs to be known.  Without the left block there is no completion of the hip and response/reaction. Biomechanical analysis  also confirms the final action of the hip comes from the impact/reaction to the left block. Stretch before plant and block while stay back and relaxed. He plants with the right shoulder way back and creates the necessary amount of acceleration he need to rise the arm velocity from 5-7m/s to 30-33m/s.

“Stay back!” … short impulse over left to get feet ahead and keep shoulders back to preform best use of Torricelli’s equation. The equation itself is:[1]

Vf^2 = Vi^2 + 2.a.Δx

where
^2 – is the square of
Vf – is the object’s final velocity along the x delivery.
Vi – is the object’s initial velocity along the x delivery.
a – is the object’s acceleration along the x delivery, which is given as a constant for simplification propose.
Δx – is the object’s change in position along the x delivery length, also called displacement.” – Carlos M D Cunha, thrower’s coach

Over the course of throw:
• good rhythm and balance
• firm block wilh the left side
• super-delayed strike with the throwing arm and a hip-chest-shoulder-elbow-hand distribution of power effort.

Modeling javelin throw.  Initial velocity before the throw is key in distance reaching!

 

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