LA84 Coaching Education Advanced Clinic Biomechanical Commonalities of the Horizontal Jumps

LA84 Coaching Education Advanced Clinic

Biomechanical Commonalities of the

Horizontal Jumps

Cameron T. GaryMater Dei Catholic H.S. – Chula Vista, CA

USATF Level 2 - Jumps

How do we jump? “Triple extension” of hip, knee

and ankle joints Fast & Coordinated Until foot release

All three must happen in order to “jump”

“Summation of Forces” Non-extension of any one joint

makes the jump inefficient

VERY basic movement Not “functional”, per se

Basic Jumping

Main Characteristics Pushing only Strength-oriented Overcome inertia - move from a stationary position

Body at rest tends to stay at rest… Sprint starts Beginning of approach run

We train this attribute through: Bodyweight Exercises (e.g., Lunges) Conventional weight lifting

squats, power cleans, snatches, dead lifts, etc. Jumping up onto a surface Running up stairs

Concentric Jumping

Eccentric & Isometric Strength Eccentric Contraction

Muscle lengthens under tension Such as lowering the weight on a Bench Press

Stronger than Concentric One can lower more weight than they can lift

Isometric (“isolate” + “measure”) Muscle contraction w/o movement of joint Very brief but very important

These attributes are trained by: Lowering and/or holding weight

“Farmer’s” Carry, etc. Running/jumping then stopping (“Catching”) Jumping down (“Sticking”) Running down stairs

Increase tension before concentric contraction Eccentric and Isometric

The resulting concentric contraction is stronger Can utilize some of the muscle’s elastic properties

Analogous to stretching a rubber band

More Functional Dorsi-Flexion of foot before planting Cocking the arm for a punch

Pre-Recruitment

Full foot – the most basic skill a jumper must learn The same for the Long Jump and Triple Jump But not a “dead” foot

Dorsi-flexion enables pre-recruitment of muscles Emphasize the middle of the foot striking the ground

Activates the larger muscles of the upper leg and hip NOT heel first NOT toe first Deliver a Blow to the Runway/Board

“Pawing” – It may encourage dropping the toe (BE CAREFUL!) Useful verbal cues:

Squish a bug Break a board Push a skateboard

Basic Applied Skills

Counter-Movement Jumping Rapid weight drop

Temporarily “increase” weight W/O increasing mass

Descent is briefly stopped Quickly reversed Isometric strength must be great

Arms increase force into the ground Applied downward then upward Body “lightens” as a result Energy is “returned” to the body

Increased force into the ground = increased energy return to the body

Demo Basic CM Jump

Plyometric “Springy” Effect Stretch-Shortening Cycle

RAPID Absorption > Stabilizing > Explosion The FASTER the better Focus on dynamic power (strength vs. time)

Develop functional tension (within reason) Analogy: Bouncing rubber ball

The harder the ball, the higher the bounce

Maximum speed sprinting Shallow knee angles – Fast ground contact Multiple “jumps” down the track

One cannot “push” fast enough Sinusoidal movement of pelvic girdle

“Horizontal” jumping really isn’t horizontal Transitional vertical impulse – just like sprinting

“Loading” the Plyometric Spring Foot strikes are active – “negative foot speed” NEVER foot strike toe-down – common issues:

“Double hit” and/or foot “stammer” Encourages reaching far ahead of the COM

Premature hinged-moment This is what you do when you want to stop

Activates the smaller muscles – think “Proximal-Distal” Be VERY careful with the so-called “B-Skip”!

Foot Dorsi-Flexion “loads” the Achilles tendon Prepares calf/hamstring muscles for a stronger response Be careful of how you drill

Anything worth doing is worth doing right No point in practicing things that weaken athletic skills

You have to get down to get up Dwight Phillips LJ video

If you imagine a pogo stick w/ wheels, you understand the hinged-moment This is what propels a pole-vaulter over the bar

However, there is stored energy in the flexible pole – same for muscles Is what allows us to jump vertically while moving horizontally

The reason for the penultimate/pre-recruitment transition Foot contact “checks” horizontal velocity - imparting forward rotation

Hinged-Moment Analogy

Effect of Forward Rotation The body rotates around the COM

Parabolic Path is Established at Takeoff Can maximize or mess it up…but not extend it

Minimize excessive forward rotation Utilize some forward rotation

Posture Upright at take-off (neutral spine) Upright during flight NOT upright at landing

Feet land relative to body rotation around COM Abdominal strength has NO effect on this

Project Center of Mass (COM) As far as one can, from the board, into the pit Path is determined at take-off However – there is a constant battle vs. forward rotation

Optimal take-off angles – why? 18 – 22 degrees – horizontal velocity is main contributor to distance

Project COM out, not up

COM starts from above the ground

Horizontal Jump Objective

Action-Reaction Newton’s Laws…

Every action causes an equal and opposite reaction Problem manifested – result of what precedes it

Arms relative to Torso Set the pace/tempo Rear Arm Sweep Example

Horizontal Vertical

Legs relative to whole body (flight mechanics) Same affect as the arms, but bigger Hitch-Kick Effect

Legs push hips forward, arms push torso backward

Triple Jump Demo (Idowu)

Mass is NOT weight Mass is a function of matter Weight is a function of the magnetic

pull of mass toward the earth’s core Earth vs. Moon

Body Positions re: COM Standing Bending

Front Side

Arms play a role – DON’T forget them!

Relevant to the flight Especially landing positions Arms forward v. backward

Center of Mass

Wall Test

Momentum (Mass x Velocity) – VERY Important

Start of approach - main attribute: strength/power Top speed/end of run - main attribute: speed/reaction Only necessary for horizontal jumpers to maintain high running

velocities for 10 – 15 metersLong interval running is not necessary (may be counterproductive) for

jumpers!Use short rest intervals to develop anaerobic power

However, jumpers must be able to run VERY fast!But under control

Jumpers must convert horizontal to vertical QUICKLYSkipping a stone on water – TJDelivering a blow to the board – LJ

It is possible to run even faster than sprinters at the end of the approach

Almost ALL jump distance is determined at take-off

The last few strides of the approach determine take-off

In-Air movements only obtain optimal landing positions

Majority of training should focus on how to transfer the run into the jump

Believe it or not…

(1993 and 1995 World Championships) “Biomechanical Team’s Information Bulletins” Conley is the faster sprinter, but as one can see – it is

the speed over the last five meters that tells the tale

Can jumpers really run faster than sprinters in the approach? Edwards v. Conley

Summary & Questions

Cameron T. GaryUSATF Level 2 - Jumps

www.ctgdevelopment.net619-895-4699

[email protected]