SPRINT MECHANICS: WHAT TO LOOK
FOR & HOW TO EFFECTIVELY MAKE CHANGES! Mike Young, PhD HPC - Athletic Lab Cary, NC @mikeyoung #speedsummit

•General Concepts of Sprinting •Motor
Learning Fundamentals •Optimizing Acceleration Mechanics •OptimizingTransition Mechanics •Optimizing MaxV Speed Mechanics •Take Home Points

GENERAL CONCEPTS OF SPRINTING by
Hugo Faasta

BACK SIDE MECHANICS Refers to
the motions of the swing leg that occurs BEHIND the body

FRONT SIDE MECHANICS Refers to
the motions of the swing leg that occurs IN FRONT of the body

ACCELERATION CHARACTERISTICS • Velocity @10m:
~8.2 m/s! • Ground ContactTime: ~0.17 sec! • Height of foot @ 1st step: 12-30cm! • Stride Frequency: 3.6-4 Hz! • Stride Lengths: ~1.5m first step

*MaximalVelocity: ~12.8 m/s! ! !
*Ground ContactTime: ~0.08 sec! *40-45 steps for sub 9.80 100m *Stride Frequency: ~5 Hz! ! ! *StrideVelocity: ~300 deg / sec! *Stride Lengths: 2.25-2.7m MAXIMALVELOCITY CHARACTERISTICS

KINETIC PARAMETERS • Ground reaction
forces approaching 5x bodyweight! • Muscle forces in excess of 7x bodyweight

Sprinting 101 Small Mass +
Big Force + Right Direction + Minimal Time Run Faster

• To increase running speed
an athlete must increase force to the ground in the appropriate direction and do so over increasingly shorter periods of time! • Minimize horizontal braking forces*! • Increase propulsive forces FORCE DEVELOPMENT & SPRINTING

Horizontal vsVertical Propulsive Forces....! and
why you don’t have to pick a side

VERTICAL FORCE MATTERS… Rela%onships,among,jumping,performances,and,sprint,parameters, during,maximum,speed,phase,in,sprinters,,by,Kale,,Asci,,Bayrak,and,
Acikada,,in,Journal,of,Strength,and,Condi%oning,Research,,2009!

from Strength & Conditioning Research
…BUT SO DOES HORIZONTAL FORCE

THE LEG AS A SWINGING
SPRING

• Refers of the ability
of the leg to act as like a spring • Momentum is developed during acceleration • Body will move at same rate unless acted on by unbalanced forces • Two external forces will cause deceleration • Leg stiffness increases vertical impulse, shortens ground contact and increases elastic return INCREASE LEG STIFFNESS

• Increased vertical force produces:!
• Greater displacement! • Stiffer spring! • Better maintenance of momentum VERTICAL FORCE PRODUCTION

Vertical Displacement? The path of
COM will follow a sinusoidal curve when viewed in the sagittal plane COM reaches apex in flight COM low point during support

Vertical force production is the
key component of top-end speed and that in turn influences the ability to maintain a slight increase in stride length and stride frequency Dan Pfaff

Charlie Francis To go faster,
you need more force. The more force you apply, the higher you will rise off the ground.

Better sprinters may appear to
bounce In reality, flight times are similar and ground contact times are shorter

• Stride frequency is comprised
of two components: ! 1. Ground contact time ! 2. Flight time! • The best sprinters spend less time on the ground ! ◦ Greater frequency MORE SPRINT MATH

The benefit of greater force
application is two-fold:! • Increased stride length • Increased stride frequency STRIDE LENGTH & FREQUENCY

To run faster there is
only ONE solution

Apply More Mass Specific Force
to the Ground!

Motor
Learning

Sprinting is an extremely complex
motor task involving repeated rapid ‘switching on and off’ of practically every muscle in the body

Dr. Ralph Mann Sprinting fast
is an unnatural activity

Loren Seagrave

TRUE learning is assessed by
retention

Things to Consider Intrinsic vs.
Augmented feedback Knowledge of results vs. Knowledge of performance Novice vs. Expert

X

Internal vs External Cues

Feedback
Frequency

Clear.
Concise.
Concrete.

Accelerate like a plane taking
off

Elbow the short person

Hit the ground like a
sledge hammer

You’re running like a hamster
in a spinning wheel

Make your legs
like pistons

Good Feedback is like Triage…
Don’t fix a hangnail before a heart attack

Optimizing
Mechanics

General Sprinting
Mechanics

•Better sprinters are front-side dominant
•Better sprinters have shorter contact times •Full extension neither needed nor beneficial •Ideal touchdown characterized by swing knee even with support knee

POS TU URE

The first most important aspect
of speed is posture. TomTellez

Posture is like the mast
and rudder for the limbs

Posture Trunk Erect Head Level
Hips Tall Posture

• Movements of the limbs
originate from the core of the body! • Proper stabilization and alignment of the core ensures appropriate movements of the limbs POSTURE

PELVIC TILT Posterior Tilt =
less hamstring tension, more QFM tension! Anterior Tilt = more hamstring tension, less QFM tension

Acceleration: What to See. What
to Say.

What to See • Big
split of arms & legs • Forward lean (from the ankles) • Neutral postural alignment pushing through long axis of body • ‘Complete’ pushes & triple extension • Low heel recovery • Gradual progression of body angles

What to Say • “Knees
to chest” • “Shade the sun” • “Feel the feet behind you” • “Push the ground away” • “Legs like pistons” • “Push, Push, PUSH!” • “Drag the toe” (even though you don’t want them to) • “Step over the ankle” • “Push yourself up”

Transition:WhatToSee.WhattoSay.

What to See • Continued
progression of body angles • Preservation of posture • Gradual changes in limb movement magnitude • Progressively higher heel recovery during swing phase

What to Say • “Push
yourself tall” • “Tuck the hips” • “Cheek to cheek” • “Step over the ankle, step over the calf, step over the heel”

Top Speed: What To See.
What To Say.

EFFECTIVE GROUND
CONTACT POSITION

What to See • Upright
posture • Powerful & dynamic arm swing (not locked at 90 deg) • High knee recovery • Front side dominance • Relaxation in face, shoulders, hands • Foot contact under the hips • ~Vertical shin angle at GCT • Pre-activation prior to contact

What to Say • “Balance
a bowl on your head” • “Slam the elbows down” • “Step over the knee” • “Feel everything in front” • “Imaging you have a rubber band from you heel to your butt” • “Make your eyelids jiggle” • “Run tall and bounce” • “Push up” ….or “Push down” • “Be a super bouncy ball”

Creating a learning
environment

Creating a learning environment Try
to coach without “coaching” by creating an environment that facilitates motor learning Create contextual interference by varying trial type & order Tools & specific environments can make motor patterns idiot proof

Block Serial Random Falling Start!
Falling Start! Crouch Start Falling Start! Crouch Start Falling Start! Falling Start! Starting Blocks Crouch Start Falling Start! Falling Start! Starting Blocks Crouch Start Crouch Start Falling Start! Crouch Start Starting Blocks Starting Blocks Crouch Start Falling Start! Crouch Start Crouch Start Crouch Start Falling Start! Starting Blocks Starting Blocks Starting Blocks Starting Blocks Falling Start! Crouch Start Starting Blocks Crouch Start Starting Blocks Starting Blocks Starting Blocks Falling Start! Increase Contextual Interference to Enhance Skill Acquisition

Practice Variability? Increasing Variability Enhances
Learning Surface Weather Block position Gun vs Clap Alone or with partner

FRAMEWORK FOR SKILL ACQUISITION Contextual
Interference Movement & Task Variability Low Practice Variability Beginners Experts Intermediate High Practice Variability Low Contextual Interference High Contextual Interference Wu, 2008

Use Tools And environments that
facilitate learning

SPRINTING IS A SKILL SPRINTING
FASTER IS THE RESULT OF PUTTING MORE FORCE IN TO THE GROUND AT AS LITTLE BODY MASS AS POSSIBLE BETTER PRACTICE DESIGN IMPROVES SKILL ACQUISITION WHICH ALLOWS MOVEMENT TO BE AUTOMATIC, REFLEXIVE & EFFICIENT THE WAY A MESSAGE IS DELIVERED IS JUST AS IMPORTANT AS THE MESSAGE UNDERSTAND THE BASICS OF MOTOR LEARNING BEST PRACTICES

@MIKEYOUNG! ATHLETICLAB.COM! ELITETRACK.COM! FITFORFUTBOL.COM! HPCSPORT.COM!
SLIDESHARE.NET/HPCSPORT! THANKS