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Speed Development & Enhancement
Transcript of Speed Development & Enhancement
Understanding the tenants & tools for sprinting success.
Dr. Brad H. DeWeese
What is Speed?
: Sprinting speed is defined with the frequency and length of strides (Mann & Herman, 1985).
SL x SF = Speed
Definition of Max Speed
: Fastest steady speed attained during the "Plateau" phase of a sprint, when the average speed over 1 stride is relatively constant from stride to stride (Miller, Umberger, Caldwell 2012).
Performance in sprint events is based on an athlete's:
1. Ability to accelerate
2. Magnitude of maximum velocity
3. Ability to maintain velocity against fatigue.
(Ross, Leveritt, & Rick 2001)
The acceleration of a sprinter is determined by 3 external forces:
Factors related to Goal Attainment in Sprint Events
C. Ground Reaction Force
= Controlled by Athlete
Ground Reaction Forces
The force exerted by the ground on a body.
Manipulations to GRF can be made through biomechanics.
Biomechanics can be influenced by proper strength development & optimized physiological changes.
Sprint ability may be limited by an athlete's Rate of Force Development
Rate Of Force Development
RFD can be defined as the rate of rise of contractile force at the beginning of a muscle action (Aagaard 2002).
Current standards of excellence of RFD & Impulse at 90ms
Current Standards of Excellence in Sprint Ability
The Velocity (m/s) of World-Class Female Sprinters over first 20m
The Ground Contact Time of World-Class Female Sprinters over first 20m
The 20m mark is critical as research has shown that elite sprinters achieve more than 80% of their maximum speed by this distance (Bruggemann et al, 1990).
Potential Benefits of Proper Speed Development
1. More efficient movement through temporal sequencing.
2. Increased Nerve Conduction Velocity.
3. Altered motor unit recruitment strategies.
4. Increased ability to maintain muscle recruitment.
Ross et al. 2001
So is speed that simple?
The Constructs of Speed
Increases in speed are a result of:
1. Applying greater ground support forces;
2. Using shorter periods of foot-ground force application;
3. Repositioning the swing limb more rapidly.***
= Resulting in taking less time in the air between steps.
Weyand et al. 2010
**Swing limb repositioned at similar speeds for runners of varying abilities.
Weyand et al. 2000
Sprinters do not have ample time to produce their maximum forces
GCT ~ .83-.90 ms
Should You Artificially Manipulate GCT???
In theory, increasing GCT would allow for greater force production.
1. The aim is to beat your competitor to the finish line
2. Increasing GCT may result in alterations of mechanical efficiency
(swing leg/ dangle time)
3. Dampen effects of spring-like rebound of body (
) via the spring-mass model (Blickhan 1989; Farley & Gonzalez 1996).
THE REAL ISSUE
Let's Summarize What We Know About Sprinting.
1. High Vertical Forces
2. Minimized GCT
High Rates of Force Development
4. Mechanical Efficiency
5. Spring-Like Actions via SSC
SO HOW DO WE ADDRESS THESE REQUIREMENTS?
Enhance Speed through Proper Programming
Improvements of an athlete's SL (without risk to SF or efficiency) is best achieved through long-term development of strength and power.
Building Sustainable Speed
Procedural Memory Development
The psychological basis for "short to long"
The memory of how to perform a task
Type of Implicit Memory: A memory in which previous experiences aid in performance of a task without conscious awareness.
Developed through procedural learning which is the repeating of a complex task until neural proficiency and mapping exists.
1. Speed development should occur in concert with other training agendas.
2. Recall that sprinters produce high vertical forces in a short period of time.
3. Speed may be limited by an athlete's RFD.
Evidence supports metabolic training doesn't facilitate necessary improvements in speed
(Bundle, Hoyt, & Weyand, 2003)
The Short to Long Training Approach
Philosophy of training that suggests speed is best improved by the early refinement of acceleration abilities which will bolster later training phases that emphasize longer-distance sprints at higher speeds.
Asks the fundamental question:
Why run 11m when you cannot run 10m correctly?
Before you get carried away on the strength conundrum.....
Strength training isn't the issue..... it is the process and design!
Non-specific hypertrophy / Low associates to sporting form
Abe, Kojima, Kearns, Yohena, Fukuda (2003)
Wakahara, Fukutani, Kawakami, Yanai (2013)
1. Introduce strength endurance
2. Transition into rudimentary maximal strength
3x10 to 3x5
3. Utilize basic strength movements
1. The development of metabolic qualities required for future blocks.
A. Improved enzymatic sensitivity
B. Increased iso-enzyme activity
C. Mitochondrial/ capillary density
= Increased Phosphate turnover
2. Prescription of basic strength movements.
A. Many coaches continue to "turn the bar over" in fear of losing RFD.
B. However, temporary removal
3. Increase the benefits of full Olympic lifts through the implementation of derivatives.
A. Pull to Knee
B. Clean & Snatch Grip Shoulder Shrug (DKB)
C. Pull from Floor (DKB)
D. Mid Thigh Pull (DKB)
Evidence of the Supercompensatory actions resulting from the removal and re-implementation of explosive activities during a strength-endurance training block.
Let's See These Factors in Action
Why focus on acceleration through incline sprinting?
1. At beginning of a training year, even an Olympic level athlete has lesser strength values in relation to their competitive abilities.
2. This training state compromises ability to hold positions. Hence, athlete may prematurely come out of acceleration phase.
Benefits of Inclined Sprinting
1. Improves propulsion forces.
2. Reinforces proper shin angles.
3. Requires athlete to maintain low heel recovery.
4. May improve stride length upon return to flat.
"Brings the ground to the athlete", which:
3. Focus in general prep is also on strength-endurance. Thus, fatigue from weight room can prevent athlete from hitting proper sprint positions. SO..................................
1. Maximize accelerative abilities through incline sprinting.
2. Transition to flat-ground sprinting to further bolster acceleration phase through improved strength & body positioning.
3. Introduce speed endurance if and when applicable.
And Just for Fun......
The Math of Winning
Krzysztof & Mero, 2013
100m WR: 9.58
Wind: 0.9 m/s
Body Mass: 93kg
1. Nearly 20cm taller than rest of field in 2009 WR & 2012 Games.
2. Weighs roughly 15kg more than other finalists.
3. Completed the run in 41 strides (2.45m per stride)
4. Competitors took 43-48 strides (2.20m per stride)
5. Highest max speed 12.34 (between 60-80m).
Are Resisted Sprints Worth the Investment?
1. Resisted sprinting tools defined in literature as: Towing, Wind, Hills.
2. Letzelter (1995) postulated resisted sprinting alters biomechanics thus "decreasing" sprint ability.
- However, load may have been too great.
What does the study of World Class athletes show us?
More suitable measure is to ensure "load or incline" does not result in a change in velocity greater than 10% over a given distance (Jakalski 1998 & Lockie 2003).
Changes in stride length following 2 blocks emphasizing acceleration development through incline-sprinting.
Data demonstrates incline-sprinting increased stride length.
However, step velocity was not dampened.
How does Stride Length Relate to Sprint Ability?
1. Classically speaking.......Maximum speed may be improved by increasing stride length or stride frequency (Kryolainen, Komi, & Bell 1999; Luhtanen & Komi 1978)....however.....
- At top speed,
sprinters take longer strides than their slower counterparts
(Armstrong et al., 1983)....
a display of vertical force production
(Weyand et al., 2006).
- A result of proper training.
Further Understanding Acceleration Development
Thus, it begs the question...........
1. Continue to develop & refine Maximal strength.
2. Manipulate Volume-Load to revisit "Maximal Strength Endurance" and maintain biological adaptations.
3. Continue to utilize basic strength movements while bridging into RFD yielding lifts.
3x5 to 5x5 to 3x5
1. Complete the refinement of acceleration through the transition into flat-ground sprinting
2. Begin to touch on introductory maximum velocity work.
3. Implement longer speed (event specific) strategies as necessary.
A. Acceleration Holds
B. Towing and Complexes
C. Starts from lowered positions.
A. Extend zone of acceleration portion of "Accel Hold"
B. Short Build-Up Fly-Ins, etc.
C. Flat Ground will ultimately provide higher velocities than incline.
A. Speed Endurance (Longer accel holds)
C. Broken Runs/ Hollow Runs
WHY WAIT FOR "VELOCITY" TRAINING?
1. Remember max velocity sprinting requires production of high vertical GRF in short stance time (Weyand 2000).
2. Therefore, "maximize" max velocity training by ensuring athlete is strong enough to produce high propulsive forces in a short time period.
Pre/ Early Competition
1. Highlight "Absolute Strength" through lower VL of traditional vertical force producing activities (squats).
2. Begin to "converge" strength qualities through more complex exercises and training tools.
3. Focus on higher RFD through:
A. Promote strength through clusters
A. Proper exercise selection
B. Continued manipulation of VL
Benefits of PROPER Weightlifting on Sprinting
1. Maximum velocity sprinting requires high propulsive forces in a short amount of time.
2. The SSC contributes to the propulsive force.
3. Weightlifting movements emphasizing the DKB utilize and ENHANCE the SSC.
1. Maximize velocity through more complex sprint training:
2. Maintain accelerative abilities through:
3. Where applicable, mature speed & special endurance qualities:
A. Fly-In (Longer build and fly zones)
B. Race Modeling
C. Complete Sprints
D. Potentiation Complexes
A. Low Levels of Towing
B. Potentiation Complexes
C. Reactive Starts
A. Complete Special Endurance runs (multiple reps)
B. Longer Acceleration Holds
1. Continue to mature RFD and explosive abilities through proper exercise selection.
A. Full weightlifting movements.
B. Partial Movements (Mid-Thigh Cleans, CMS)
C. Squat Jumps
2. Promote maximum output of each repetition through loading schemes.
A. Reduced Volume-Loads
B. Partial movements when necessary
A. Enhance recovery and heightened RFD through clusters.
B. "Potentiate" velocity of reps through wave-loading.
C. Prescribe complexes if and when necessary.
3. Ensure recovery and limited residual fatigue through:
1. Racing assists in maintenance of athlete's abilities.
2. Practice choices determined by athlete's energy status and competition schedule.
A. Longer breaks in competition schedule allows for velocity stimulation in practice.
B. Weekly competitions may require a coach to utilize practices that stimulate the athlete in ways racing does not.
C. If questions arise, the best approach is a conservative approach.
3. "Peaking" can occur through a fast-decay, which is stimulated through a sudden decrease in VL..... not intensity
Putting It Together
Progression of Strength Training
Progression of Speed Development
Correct GPP Includes: