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Copyright © 2014 by Jimson Lee, SpeedEndurance.com Page 1 7 Scientific Answers to Common Coaching Questions for Sprinters A Roundtable Discussion compiled by Jimson Lee, SpeedEndurance.com

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Page 1: 7 Scientific Answers to Common Coaching Questions for ... › USATF_ASSOC_59 › files › ...Carl Valle: The saying goes, god makes sprinters, coaches make milers use to be popular,

Copyright © 2014 by Jimson Lee, SpeedEndurance.com Page 1

7 Scientific Answers to Common

Coaching Questions for Sprinters

A Roundtable Discussion compiled by

Jimson Lee, SpeedEndurance.com

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Copyright © 2014 by Jimson Lee, SpeedEndurance.com Page 2

Introduction:

I feel this document is a valuable tool for both athletes and coaches to understand how

coaching, biomechanics, and sport science are all related.

I wanted to collect the thoughts from a wide variety of people, including Coaches who has

produced Olympians, Former Olympic athletes becoming coaches, Sport Scientists,

Inventors, other Coaches, and so on.

A coach is measured by results, not by knowledge. So please read carefully and apply their

knowledge to your training program.

There is no right or wrong answer. Just some answers better than others :)

This ebook is free of charge. You may freely distribute this as long as you do not charge for

it. You may not change or modify any of the content, including the links.

If you wish to receive more of these reports, please sign up at

http://speedendurance.com/newsletter/

About Jimson Lee

Jimson Lee is a Coach, Masters Athlete and founder

of the Blog SpeedEndurance.com. It was foundind

in 2007, and received over 2 million pageviews in

2013.

SpeedEndurance.com articles have been quoted in

ESPN, BBC, NY Times, Yahoo Sports, Sports

Illustrated, Yahoo’s College Football, San Jose

Examiner, and Wikipedia.org.

The articles were also referenced in the printed

edition of ESPN Magazine and The Globe and Mail,

Canada’s National newspaper.

Zen Habits ranks SpeedEndurance.com as one of

the 20-plus Amazing Fitness Blogs to Inspire You.

Jimson is a member of the Track & Field Writers of America, and writes for the IAAF New Studies in

Athletics journal.

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So these are the common 7 questions over the years by Email and Facebook messages:

Q1. Is sprint running primarily an acquired skill or innate ability? Are sprinters

born, and not made?

Q2. What are the mechanical requirements for achieving fast running speeds?

Q3. Which muscles or muscle actions should a coach focus on while training away

from the track?

Q4. What is the relative importance of stride frequency vs. stride length for top

speed running?

Q5. Is dorsiflexion of the ankle joint prior to ground contact beneficial and if so,

why?

Q6. What is the importance of arm swinging in sprinting?

Q7. Does the action of sprinting involve more of a pushing action or a pulling

action against the ground?

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The Interviewees:

Here is a quick Bio of each of the people responding.

Dan Pfaff is currently the Director of Education, Head Coach, World Jumps and Combined

Events Center at the World Athletics Center in Phoenix, Arizona. He has tutored 49

Olympians including nine medalists, 51 World Championship competitors (also nine

medalists), and five world-record holders. Dan has served on five Olympic Games coaching

staffs in five different countries and nine World Championships staffs for six different

countries. His recent 3 year contract was in London with UK Athletics, where he coached

Long Jumper Greg Rutherford to Olympic Gold in 2012.

Visit http://worldathleticscenter.com/ for more information.

Jimson Lee (answers researched from Dr. Peter Weyand's documentation). These

answers were researched from sourcing previous lectures, videos & journals of Dr. Peter

Weyand who is widely recognized as one of the world’s leading scholars on the scientific

basis of human performance. His research on the mechanical and physiological basis of

sprint exercise performance continues to advance scientific understanding and shape

contemporary training practices.

Dr. Weyand is an Associate Professor of Applied Physiology & Biomechanics and Director of

the Locomotor Performance Laboratory at Southern University in Dallas, Texas. Their unique

testing facilities at the Locomotor Performance Laboratory have made the performance lab a

draw for world-class speed athletes from across the globe.

You can check out their YouTube channel

at http://www.youtube.com/user/LocomotorLabSMU

Kenta’ Bell is a two time USA Olympian (2004, 2008) in the Triple Jump and the 2001 Gold

medalist at the World Student Games in Beijing, China.

His PR is an impressive 17.63m and he is also the 2003 & 2010 USA National Champion. By

then, he was ranked as one of America’s top ten triple jumpers in each of the past nine

years by Track & Field News.

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Kenta' guest writes for SpeedEndurance.com with articles, podcasts and videos, which can

be found here:

http://speedendurance.com/tag/kenta-bell/

Carl Valle is a USATF Level 2 Sprints and Hurdles coach and guest writer for various

websites, including SpeedEndurance.com

Since 1997 he has helped athletes improve speed and power in various sports and his areas

of interest are technology and regeneration. He has coached high school, college, junior

college, and post collegiate athletes and the results of their hard work resulted in accolades

ranging from school records to All-American status.

Carl provides support services to post collegiate athletes on his website Spikesonly.com. He

is also a regular contributor to FreelapUSA, and other online magazines and Blogs.

Carl's guest articles and interviews can be found here:

http://speedendurance.com/tag/carl-valle/

Adarian Barr is the Assistant Track Coach, Jump/Hurdles/Multi-events at the University of

North Carolina in Pembroke. He is also a movement specialist at Next Level Athletics and

Fitness, as well as the inventor of PALO (which means “STICK” in Spanish).

Adarian's many guest articles and interviews can be found here:

http://speedendurance.com/tag/adarian-barr/

James Smith recently wrote a book titled Applied Sprint Training. His websites include

globalsportconcepts.net and athleteconsulting.net

James is a student of Soviet and Eastern Bloc training methodologies and is engaged in the

constant pursuit to further his own physical conditioning and coaching abilities.

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His resume includes athletes from Track and Field, Division 1 American football, Mixed

Martial Arts (MMA), Brazilian Jiu-Jitsu, USA Volleyball, and other Olympic sport disciplines.

James' guest articles and interviews can be found here:

http://speedendurance.com/tag/james-smith/

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Q1. Is sprint running primarily an acquired skill or innate ability? Are sprinters

born, and not made?

Dan Pfaff: I think there are factors of both evident depending on sport and event specifics.

There is no doubt one can improve their current levels with directed coaching. As for

sprinters born and not made, they may be born with innate talents and gifts but without

proper programming, mechanics, lifestyle and medical inputs, tons of talent lay wasted in

the fields of sport.

Jimson Lee on Peter Weyand: Sprint running is a complex skill whose execution depends

directly on the musculoskeletal biology of the athlete. The ability of sprinters applying

ground forces of 4-5 times the body’s weight in less than one-tenth of a second without

losing their balance, while reversing the vertical direction of the center of mass, and with

negligible fluctuations horizontal velocity during each stance phase requires both great skill

and high-level musculoskeletal function.

The critical question for coaches and athletes is to what extent both the skill and

musculoskeletal function aspects of speed are trainable. Clearly, training can improve

speed, but despite the fundamental importance of speed for athletic performance broadly,

the data available for quantifying and understanding training-induced improvements in

speed is surprisingly limited.

Researchers can begin to document and better understand the extent of the gains in speed

that are possible through:

1. regular high-speed running

2. strength training

3. improved motor control

Kenta’ Bell: I would have to answer by saying both. Yes some guys are born genetic

freaks and they just get it. likewise, it's pointless to ask the guy with huge biceps in the

gym how he got them when you've never seen him do an arm curl. So yes, it is safe to say

some people are just born to run fast without little thought or explanation as to how they

achieved this skill. However, I firmly believe that speed can be taught and built over time.

Let's not mistake this as saying anybody can be a world class sprinter. Speed is relative to

the individual. I think any individual under the right tutelage can be taught to run faster

and more efficiently in their mechanics. I will venture further to say that the Myth: "in order

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to run fast you have to train fast" has led many astray. You cannot teach and hardwire

anything at full speed. Acquiring speed is a masterful skill and art and must be trained with

quality time and patience; just as you would learn any other skill such as guitar, piano, or

violin. Sprinting is a high precision skill. These skills are to be performed as correctly and

consistently as possible, every time. They are skills that have one path to an ideal result.

Learning fundamentals, hard precision skills requires one to go slowly and make one simple

move at a time. Repeating and perfecting it before moving on. developing speed is like

eating, you have to do it daily. If only for five minutes a day you have to nourish the

process.

Technique is everything

Carl Valle: The saying goes, god makes sprinters, coaches make milers use to be popular,

but I would say sprinters are born, and coaches make them faster. Many elite sprinters

have succeeded with difference coaches and many average coaches have looked really good

with great talent. Talent is the major element in success in sprinting. The ability to run is

what we are given genetically, but sprinting is a little more skilled due to the margin of error

in winning and losing. Our body has adapted and been gifted with an array of physiological

and morphological abilities to sprint naturally, and coaches are there to put the frosting on

the cake. Some athletes will improve more than others, but hard work and good coaching

can improve anyone, no matter how talented. I think sprinting is amazing and some may

argue it’s a highly complex interaction of motions but our bodies are designed for

locomotion and it’s best not to overthink. The greatest sprinters are just relaxing from years

of rehearsal, so while we can dig and understand the body more and more, much of that

information is coaching candy, interesting, but not productive.

Adarian Barr: Fast runners are born but sprinters are made.

Sprinting is definitely a skill that not many fast runners acquire I would say Ben Johnson

and Usain Bolt, Asafa Powell were made sprinters while Calvin Johnson was a fast runner

that never acquired the skill of sprinting. Bob Hayes even Jesse Owens fast runners. On the

female side, Evelyn Ashford was a fast runner while Flo jo was a made sprinter.

James Smith: The morphobiomechanical foundations are passed on via genetic material

from the athlete’s parents and then influenced via phenotypic factors. In this way,

the potential to sprint fast is predominantly rooted in genotype; however, that is by no

means the end of the puzzle. I underline potential because the integrity of house similarly

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depends upon the foundational prerequisites of its foundation; however, the foundation

alone in no way constitutes the entire architectural framework.

Biomechanically, even those athletes fortunate enough to be the recipients of the genetic

lottery ticket must capitalize upon these foundational prerequisites with optimal training.

As I expounded upon in my recent Applied Sprint Training manual- anyone has the ability to

run fast relative to their own capacity; however, no one is able to sprint fast (relative to

their potential) without proper training.

Perhaps the most practical example of this is to observe the ‘fastest’ team sport athletes in

(football, Rugby, American football, Aussie Rules, and others) and note how in nearly all

cases the observational takeaway (regarding those who have T&F coaching experience) is

pure biomotor output coupled with marginal to horrendous mechanics. Proper sprint

training is one of the unicorns of team sport preparation and therefore, more often than not,

the fastest non-track athletes demonstrate what genetically passed on material looks like

when it is not coupled with optimal training.

Once in while we see the Bob Hayes’ (American Football), Donovan Bailey’s (Basketball) and

Adam Gemili’s (football) spawned from the team sport realm; however, these cases have,

thus far, proven to be the exception and surely any of those athletes will describe the

mechanical work needed to be done, that they were not exposed to in the team sport

preparation, to advance their T&F results.

In summary, sprinters are born and then made.

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Q2. What are the mechanical requirements for achieving fast running speeds?

Dan Pfaff: This is a complex and deep question. Quickly we stress posture, limb positions

and timing, force application factors, relaxation and solid understanding of phases. The

KPI’s are well published and known but few see motion in real time and even fewer have a

tool box for remedying mistakes and errors.

Jimson Lee on Peter Weyand: The key to human speed is simple: applying large mass-

specific forces to the ground quickly.

One of the most appealing aspects of the state of knowledge in this area is how available

this essential information is to coaches and athletes. The biological basis of movement and

performance is extraordinarily complex when one considers all the events that occur from

neural activation to muscular force production to the musculoskeletal transmission of force

to the running surface. However, as complex as the details of motor control, force

production and delivery are during sprinting, a simple, informative and valuable take-home

message exists for coaches – speed is all about hitting the ground hard and fast.

Kenta’ Bell: Body Awareness! Every coach has an idea about what it should look like, but

all don't know how to translate it to the athlete. People don't know how to teach the athlete

When? Where? How? and Why? Mechanically coaches need to spend more time teaching

and explaining drills and how each drill correlates to the next. Likewise technical mastery

should be achieved before advancing to the next skill. I will clearly state that many coaches

are demanding execution of task and skills that many athletes are not physically capable of

achieving. This is either due to lack of strength, coordination, balance or the speed of

execution.

From a mechanical perspective I would strongly urge the coach to guide the athlete into

developing great posture and core strength. Your overall sense of body awareness combined

with great joint mobility and joint stability would come second on my list of mechanical

factors. Flexibility in sprinters is probably one of the most under estimated and most under

developed aspects of sprint athlete development. Fast muscle are dynamic and elastic.

When we are stretched to our greatest point is where we have our greatest strength.

- coordination

- posture

- core strength

- joint stability

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- joint mobility

- flexibility

Carl Valle: The most important ability to for sprinters is applying rapid forces and rapid

relaxation rates with a favorable power to weight ratio. No sprinter at the Olympics is

impressive in the weight room, and some are not excellent jumpers, so other considerations

must be investigated. Rapid stiffness, good elastic qualities, the ability to not to tighten up

areas that must be free, and good heads during crunch time are essential. I think the sport

psychology element is underrated but can’t replace poor training.

Adarian Barr: Think fascia lines and you will get a greater sense of the mechanical

requirements.

The mechanical requirements are shoulder range of movement, Look at any race and the

sprinter that has the greater range of movement at the shoulder joint and fast will win that

race every time.

Shoulder movement control the speed at which the legs more up and down.

James Smith: I would first elect to further hone the context down to fast sprinting,

opposed to running, speeds as, per my response to question 1, fast running may be

accomplished via poor mechanical execution. For example, it is probable that Cristiano

Ronaldo will defeat the bulk of the male non-athletes in the world in a 60m sprint; however,

when considered in a T&F context he presents a smorgasbord of mechanical issues that

would have to be resolved to compete against any number of elite female sprinters.

For example, Ronaldo performed an electronically timed 25m sprint (block start on turf) in

3.61 seconds according to the sport science television show. By comparison, in the

women’s 100m final in Berlin every competitor in the final managed a 20m split in 3.24 or

less and a 30m split in 4.27 or less (Shelly Ann Fraser Pryce went 3.03 and 4.02

respectively). After the math is done, which places 7 of the 8 sprinters at approximately

3.61 or faster at the 25m mark, it is more than clear how many of the top female sprinters

would give Ronaldo everything he wants in a distance as short as 25m.

As to the mechanics associated with optimizing sprint potential, clearly each phase of a race

features a unique set of biomechanical circumstances. If we specify the mechanics related

to the optimization of maximum velocity we must account for the predominance of vertical

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forces and the following model criteria associated with the world’s elite (taken straight out

of my Applied Sprint Training Manual):

When initiating a start from a static position ensure that the orientation of the feet,

hips, and centre of mass are situated in order to accommodate the athletes power

output and anthropometric proportions

When taking off from a low position the kinematic sequence is initiated by the arm

contralateral to the rearward leg

The position of the head and neck must be consistent with the position of the back

throughout

The sprint action is heavily influenced by the arms

The emphasis of arm action should be down, down, down

While the angle about the elbow will change during frontside and backside action, the

objective should be to hold a position of approximately 90 degrees and allow the

forces at work to take care of the rest

A complete line of extension from the shoulders down to the ankles is the objective

at toe off and the angle of extension relative to the ground, during acceleration,

must correspond to the athletes output ability

Positive shin angles during initial strides are central towards optimal acceleration

from the start

The transition from acceleration to upright sprinting should be smooth and not forced

While all great sprinters run with high knees in the upright position the focus should

be on stepping down

By focusing on flexing the big toe up, when stepping down, the athlete will establish

optimal foot position prior to ground contact

A short acceleration, less than 30-40m, should be completed on a single breath that

is either held throughout or slowly released in order to maximize stiffness through

the torso

The pendulum is optimized, during upright sprinting, when the rearward travel of the

support leg, after toe-off, is minimal

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Q3. Which muscles or muscle actions should a coach focus on while training away

from the track?

Dan Pfaff: I am a holistic/generalist on training of sprinters. I do not believe in isolatory

development of muscles or specific movements. Sprinting is a delicate symphony of factors

and in my experiences, the minute one menu item changes, the entire system undergoes a

reaction to said change.

Jimson Lee on Peter Weyand: The lower limb extensors: ankle, knee and hip; i.e., the

muscles that straighten and extend the limb into the running surface and support the body’s

weight against gravity during the stance phase.

Techniques that enhance ground force application, but do not increase the body’s mass are

likely to be most effective.

The specific exercises can take several books or blog articles to explain.

Kenta’ Bell: On the track and away from the track the coach should always focus on the

same prime muscle groups that are the catalyst to human locomotion. I have discussed

these groups in other articles but will elaborate and build upon those thoughts here.

Everybody initially wants to look the biggest and best thing "Olympic Lifts" when it comes to

developing strength/power. My theory differs strongly. I want to be the "Hinge That Swings

The Big Doors" this principle I developed when looking at what are the primary muscles

involved that coordinate the entire process of human locomotion and neuro-muscular

coordination. In this study I identified five prime movers that when trained consistently not

only boost performance and reduce injury, but also boost percentage in 1rep max on all

Olympic Lifts. My goal is to get the greatest gain while doing the least damage. This ensures

me more quality reps on the track.

The Fab 5:

- Gluteus

- Hip flexor/extensor

- Knee Stabilizer

- Gastroc/Soleus (calf muscle)

- Foot - Ankle

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One thing I will note is that I train Gluteus, Hamstrings and Core every day. Small muscle

groups can be trained daily and large muscle groups which create greater CNS (central

nervous system) fatigue are best trained every 2nd or 3rd day. I encourage coaches to pay

more attention to complete range of motion, speed of movement and extending the rep

range. Track and field and sports in general are not 1 - 3rep sports. we have multiple steps,

contacts, hurdles and reps. you have to put the athlete in the position to make a mistake

and self correct. You are what you repeatedly do.

Carl Valle: Not much. The individual needs will vary based on body type and development

level, but weight training s only complimentary to sprinters. Focusing on total body training

makes sense since every part of the body is active during sprinting, but one must

remember the purpose of lifting is supportive and not primary. A good program develops

the neurological aspects of the body and doesn’t disrupt ratios and balance of the muscles

around the hip, and spine. A lot of interest in special exercises have ruined sprinters and

failed to live up to expectations. Training should reduce injuries, increase durability, and

improve performance more rapidly than sprinting alone. Anyone focusing on the weight

room is likely doomed in the long run. I have seen 10.2 sprinters barely break 11 because

of overzealous strength coaches and some 10.3 talents that could break 10 fail to improve

because of lifting programs delivered as an afterthought by some track coaches. Do what

you need do and have criteria of what is successful and what is helping performance.

Adarian Barr: All muscles should be focuses on as it is a system, the stronger the system

the better the system functions. Focus on just a muscle group or a muscle takes away from

the total system performance.

James Smith: Indeed this is a hotly contested subject amidst the T&F community. I favor

the assembly of models based upon the commonalities shared amidst the elite of the elite.

Taking male sub 9.8 sec 100m sprinters, for example, observations will reveal that, by in

large, Usain Bolt, Tyson Gay, Yohan Blake, Asafa Powell, Nesta Carter, Maurice Green, Ben

Johnson, Tim Montgomery, and Justin Gatlin performed general weight programs.

If the 100m is the competition exercise then its mechanical and physiological divisions are

the start, acceleration, maximum velocity, and speed endurance. The specifics of each

phase represent the context defining point from which preparatory actions may be classified

according to transference.

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Here’s an example of exercises relative to the maximum velocity phase of the 100m

(another excerpt from my Applied Sprint Training manual):

Highest Degree of Transfer

Flying Sprints in which the pre-run is long enough and corresponds to that athletes

requirements to reach maximum velocity in a more relaxed fashion and the window

of max V is 10-20meters as that is the accepted distance over which max V may be

sustained

Speed Change Drills (fast-easy-fast and easy-fast-easy), the most common method

of performing these is over segments that are 20m, or more, in length and

correspond to that athlete’s speed potential. 20M + 20m + 20m for a total distance

of 60m. It is critical that the transition between segments is very smooth and largely

influenced by volitional changes in arm action. The differential in intensity will be

relatively small ~5%. In this way the easy sections will be approximately 90%

intensity and the fast sections approximately 95% intensity.

Secondary Transfer

Single and Multiple response jumps with a vertical emphasis, minimized knee

bend/ground contact times, and performed within the alactic period, such as:

Hurdle hops in which the hurdles a placed relatively close (~1meter) with the heights

adjusted to each athletes reactive/elastic ability

Depth jumps less than .75m or what corresponds to each athletes strength

preparation and reactive/elastic ability

Skip bounds with a vertical push-off emphasis

So what we see from this example is that the nature of muscle action, biomechanical, and

bioenergetic character of the phase of the race (in this case maximum velocity) that we

intend to improve must be reflected in the preparatory activities. In this way, work in the

weight room, for example, only possesses a direct transfer to the start and first few steps.

Outside of that, weight training merely represents a general organism stimulus which is vital

yet not directly related to the competition result. Clearly that reads as a paradoxical

scenario; however, this is why the weight programs may vary so much between the sub 9.8

pool of elite male sprinters.

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Suffice it to say that the general stimulus of ‘strength’ training is relevant towards improved

speed yet the biomotor, biodynamic, and bioenergetic structure of work in the weight room

ceases to directly transfer to the sprint after the athlete is a few meters away from the

blocks. Just another reason why the fastest sprinters in the world pay no particular ode of

homage to the specific nature of weight training other than the fact that it is part of their

program.

As a consequence, in my work and consulting with sprinters and sprint coaches, my only

stipulation is that whatever exercises are performed off the track are performed well. Most

important is that harmony is preserved amidst the total complex of work performed; such

that every physical action is accounted for regardless of where it occurs and, by definition,

everything is secondary to sprint training.

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Q4. What is the relative importance of stride frequency vs. stride length for top

speed running?

Dan Pfaff: Again there is a delicate ballet of ground contact times, flight times, parabolic

flight dynamics and these factors have huge interplay with SF and SL.

Jimson Lee on Peter Weyand: Speed is often considered as the product of stride length

and stride frequency, which, of course is fully accurate, mathematically.

However, from the standpoint of the relevant science, both physics and musculoskeletal

biology, we have found that conceptualizing speed in terms of forces applied to the ground

facilitates greater understanding. This is true for several reasons:

1. First, applying large, mass-specific forces to the ground quickly is the athletic

attribute that determines how fast athletes can run. Nearly all of the difference in

speed between different individuals is attributable to what occurs during the contact

or ground force application phase.

2. Second, ground force application can be directly related to muscle, tendons and bone

function whereas stride lengths and stride frequencies cannot be.

3. Third, as detailed in Weyand’s 2000 paper on sprint mechanics5, existing data

indicate that both the greater stride lengths and frequencies of faster runners result

from the application of greater mass-specific ground forces in shorter periods of

time.

4. Fourth, stride lengths and frequencies are not fixed fitness or performance

characteristics per se, but rather are co-selected in accordance with the duration of

the aerial and contact phases of the stride for different runners and in different

gaits6.

Kenta’ Bell: From a coaching perspective I would never seek to establish either of the

above mentioned independently. Countless visits to various biomechanical labs and time

spent training and studying under Dean Johnson, Tom Tellez, and Dan Pfaff I have linked

the connection to vertical force application as a means of increasing both stride frequency &

length concurrently. One of the biggest problems I occur in all athletes in track events are

problems establishing and reigning in spatial and distance consciousness. The common

tendency is to reach, lean, push or pull towards a perspective target where the objective

should be to remain discipline in technique with the feet under the center of mass and apply

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maximum force through the prescribed ranges of motion. Therefore, I strongly deviate from

searching to increase stride length. In regards to stride frequency, we need to understand

that it takes longer to run faster. Meaning, that we have to be patient enough to go through

the full range of motion of triple extension with the body while completing full range of

motion arm swings. Speed is built independently one step at a time. You cannot start

another step until you finish the one you are on. when athletes seek to improve frequency

the tendency is to forget about what the opposite side of the body is doing. I prefer applying

maximum vertical ground force which in return gives me greater extension and swing

mechanics flight time whilst increasing frequency as a result of stretch reflex of the hip

extensor/flexor and Achilles tendon muscle groups.

Carl Valle: Each athlete has a unique rhythm based on body type and power. Similar to

horizontal forces and vertical forces, stride length and stride frequency are very artificial

ways to break down sprinting. While artificial, they have value since they are good ways to

drill down to further analysis of race performance and career development. A better

approach is to see relationships between speed from electronic timing. Amazing how

everyone will look at the frequency or try to measure distance, but this game is won by the

watch. Top speed running should have a wide analysis and a good start is video, electronic

timing (not chronometers on video), and a checklist of normative benchmarks. Whatever

combination hits a faster speed is what we are looking for. The stride is a natural product of

anatomy and ground reaction forces, and the resultant from good foot strike is what we are

looking for. Ways to challenge those areas indirectly and from sprinting is the name of the

game.

Adarian Barr: Stride length needs to be redefine. The greater the stride length the

greater the flight time can be. The greater the force into the ground the greater the stride

frequency can be but it starts with stride length.

Stride length should be the distance between the heel of the leading leg to the shin of the

trailing leg at toe off.

James Smith: Well, there’s no question that higher frequencies and greater stride lengths

result in faster sprinting. That said, I do not feel it is necessary to directly coach either

quality. Instead, I favor the concept, that Charlie Francis was a proponent of, that suggests

that it is wiser to solve such problems via the performance of a drill that allows for the

athlete to achieve the proper mechanics by default.

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Regarding frequency, we know that volumes of athletes can cycle their legs fast enough,

unloaded, to sprint sub 10. The question is what happens when their feet hit the ground.

The nature of force production during ground contact is a substantial precursor to both

stride frequency and length.

I prefer to think of the force dynamics during ground contact as time specific force because

the amount of time a sprinter has to generate high forces at max V (which we know may

climb as high as five times bodyweight) is less than one tenth of a second (another reason

why weight training can only be of general consequence to the max V portion of the sprint).

In this way it follows, as Charlie always said, that weights follow speed because sprinting is

the only activity of relevance in which an athlete is able to generate that magnitude of force

in eight hundredths of a second (not to mention the muscle contractile velocities during co-

contraction). While the forces generated in a maximal Olympic lift may be substantial the

time differential between the barbell exercise and GCT at max V is massive.

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Q5. Is dorsiflexion of the ankle joint prior to ground contact beneficial and if so,

why?

Dan Pfaff: I coach this item strongly but there are many successful sprinters and coaches

who give it short shrift. In my work, I find less injuries, better ground dynamics and faster

runs once this concept has been learnt.

Jimson Lee on Peter Weyand: Active dorsflexion by the runner using the ankle flexors

before foot-ground contact may not be harmful to performance, however, queuing athletes

to dorsiflex as a strategy to improve performance makes little sense for the following

reasons:

Upon landing, and throughout the earlier portions of the stance phase, the weight of the

body weight loads the ankle extensors and Achilles tendon with enormous forces, forcibly

dorsiflexing the ankle. The gravitational forces that load the calf muscles and Achilles

tendon during the stance phase are at least 10 times greater than the forces the flexor

muscles can generate to dorsiflex the ankle prior to foot-ground contact. Accordingly, while

actively dorsiflexing the ankle via flexor contraction before landing may not impair

performance, any flexion accomplished in this manner is almost certainly functionally and

mechanically irrelevant given the extent of gravitational loading that occurs subsequently in

the stance phase.

Kenta’ Bell: As many of the readers know I'm a huge proponent of flat foot ground

contacts. I often cue athletes to drive down leading with the heel first. This is a corrective

mechanism based upon the fact that most athletes don't know where the ball of the foot is

and they are so far on the front of the foot that if i cue the heel strike. In doing so I get the

the perfect mid-foot strike with vertical force application. In regards to dorsiflexion i think is

an overly used cue by coaches. being that i like to keep all terminology and cues in theme

whether on the track or in the gym i prefer using the cue's neutral and flat foot. I will

explain with several different examples that will highlight the simplicity of my philosophy.

When an individual is standing he/she is neither dorsiflexed or plantar-flexed. The individual

is standing in a neutral position. If that person was to lean slightly forward from the ankles

in the correct sprint form you would achieve dorsiflexion. the position I'm explaining is

where the breastbone is directly over the toes. The advantage of this position is that upon

foot strike you get no collapsing of the ankle. Likewise the achilles tendon is pre-stretched

and loaded. This in return reduces ground contact time while allowing more surface area to

apply maximum force with greater balance and stability. Another way to look at it more

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simply would be to understand that we walk heel-toe, skip heel-toe, jog heel-toe, all lower

body and power lifts in the gym are performed driving through the heel and engaging the

gluteus and finishing through the toe in triple-extension. I teach to finish through the toes

not start on them. The art running using the feet is like shooting a basketball, you finish

and follow through with the fingers after extension of the shoulder - elbow - wrist - fingers.

In sprinting the process is hip - knee - ankle - toes. From birth we were pre-wired to put the

foot down flat and apply force so I see no reason to try and better what was already created

perfectly. Look at any untrained child or adult who hasn't been corrupted with improper

technical jargon, and pseudoscience and you will see what we were naturally created to do

using the foot/ankle as a secondary lever system.

Carl Valle: Nobody knows really. Video and force platforms are not revealing the unique

details of contributions of intrinsic foot muscles and general stabilizers of the lower leg. I

have seen on ultra high speed video some interesting things such as the strides of athletes

who have had failed surgical procedures to treat compartment syndrome. Each athlete had

different areas affected but also different foot structures that showed a delay or increased

ground contact time. Having power Is one thing, but applying it is more important. Center

of pressure studies may lead us to see why some athletes may get away from not having

great foot mechanics as Usain Bolt’s feet are clearly showing adaptations to massive forces

through the ground. EMG of the dorsiflexors show activity right before food strike and it

may contribute to more active foot strike. Dr. Weyand is right about how much contribution

the Achilles tendon has, but the activity of the plantar flexors is at midstance, later than at

first touch down. More investigation to foot mechanics, motion, kinetic data, and muscle

activity is needed to paint a complete picture.

Adarian Barr: Yes dorsiflexion or tension at the ankle joint is beneficial, the issue is how do

you maintain it, that comes from using the front deep arm line of the fascia system. Keep

the tension on the wrist as if you are drawing guns and the ankle stays Dorsiflex throughout

the leg cycle. Let the wrist flap and so does the ankle.

James Smith: From the standpoint that every single high level sprinter demonstrates it-

yes. It must be pointed out, however, that, in my view, it is not beneficial for a coach to cue

such an action. The biomechanical relevance is that as the ankle goes into dorsiflexion the

achilles tendon is lengthened and thus pre-tensed. The result is less movement about the

ankle during ground contact which fosters a greater elastic return and contributes to shorter

ground contact time.

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Alternatively, if the athlete were to intentionally extend the ankle (point their toe) prior to

ground contact (like a ballerina scissoring across the stage), while dorsiflexion naturally

occurs as a byproduct of ground contact, the ground contact time would lengthen.

I prefer not to direct any cues towards the ankles when an athlete is sprinting; however, I

will cue toe up (in reference to the first metatarsal) during drills such as skips and Running

A’s in order to shift the action to the hindbrain. Power speed drills are convenient for such

purposes as their reduced neuromuscular character lends itself towards frequent

performance. This then serves as a means of accruing valuable volumes of learning

experiences if only in the quasi-specific sense.

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Q6. What is the importance of arm swinging in sprinting?

Dan Pfaff: Despite biomechanical findings that arms are weak factors, I have found that

the balance and timing factors created by proper arm swing dynamics are a game changer.

Close study of both men and women world class sprinters find very strongly defined

movement paths and landmarks at each stage of the race. Does this happen through

movement experiments or via coaching is a question worth researching. WE coach arm

action daily. I do a lot of therapy on athletes and spinal issues have a huge correlation with

arm swing mechanics.

Jimson Lee on Peter Weyand: Once a runner is up to speed, the arms swing largely like

passive pendulums, providing balance, minimizing center of mass energy losses and

conserving the body’s momentum3. While arm movements are coordinated with torso and

leg movements to achieve the energy transfers that minimize center of mass energy

losses, they certainly do not control leg movements and have very little effect on the all-

important ground reaction forces.

Arms do play a more important role during the brief acceleration phase at the start of a race

than during steady-speed running, but precisely how they do so is not well understood.

Kenta’ Bell: The arm swing and usage of the arms are one of the most important areas

of sprinting. the simple improvement of arm swing and carriage in many athletes can

produce large improvements in performance. many coaches ignore the arms either from

neglect or lack of knowledge and training about their relationship with the legs and sprint

performance. I teach the athlete to first learn how to relax the shoulders and not recruit

them in the arm swing. Secondly, I begin by teaching my athletes the relationship between

up-stroke swing/punch and parallel thigh drive. The hand in my opinion should should

swing out & up. This action recruits the forearm first and the bicep second. This action also

creates a forceful blocking action that transfers both force and momentum through the track

in the correct line of force up and out. This upward swing is also very critical in maintaining

proper front side mechanics while sprinting. the angle of the thigh muscle and bicep femoris

should achieve the same angle of perpendicular alignment when driving up. Under close

observation you will recognize that when the athlete fails to stroke upwards in full range of

motion as the arms stops the knee-drive/thigh lift is prematurely interrupted. in the

mechanics of the arm the hand swings out in front vs. down and back. In the mechanics of

the leg the lower leg does the exact same and the foot kicks out prematurely and stresses

the lower hamstring and back of the knee. The next thing I teach is a full downward swing

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of the hand as the arm fully extends. This downward swing synchronizes the full extension

of the support push-off leg. Thus allowing the leg to appropriate time to apply maximum

vertical ground force through the full range of triple extension from hip to toe and back up.

The downward swing also voluntary engages the tricep muscle and stretch-reflex loads the

pectorals and deltoid muscles that are responsible for initiating the upstroke just as the hip

flexor initiate the heel recovery straight up to the bottom of the buttock and into parallel

knee drive as the arms strokes up.

It goes to say that I look at synchronization, balance and rhythm when i address the

teaching and usage of the arms in sprinting. As a jumper understood the relationship and

timing of the arm swing and block and the role the arms played in creating vertical lift. As a

result i was able to take this and transfer it directly to sprinting and creating higher

velocities by generating more vertical lift and higher ground force application.

Carl Valle: Again Peter Weyand shared some biomechanical ideas that certainly were

promising in understanding arm contribution to top speed, but we are not bouncing balls

and the body has one organ we need to look at differently, the role of the sprinters brain.

Arm carriage in running and sprinting are graphically different, but why is a good leading

question to how arms help sprinting. I have read the research and talked to Frans Bosch

and other experts, but it wasn’t until I talked to Daniel Lieberman from Harvard on the

phone did I look at arms as something not designed for sprinting but for running. This was

before the barefoot hype and he was very fair in allowing me to ask questions that may be

pointless to evolutionary biology. My belief is that arms help generate more pelvic tightness

on ground contact based on personal EMG data; on the lats and external obliques

specifically. While this was done on 10.x sprinters, the likelihood is the same information is

helpful for those that are 9.8 and faster. Arm swing speed doesn’t matter since the foot

hitting the ground is different than the arm stopping from a pectoral stretch reflex, but

sprinting is a very total body effort and should be explored. As for acceleration some

conjectures exist, such as generating a near-gyroscopic balancing effect but nobody really

knows. Acceleration is skill and we need to embrace how the arms, even if they are just

balancing components, help with timing and total body stiffness. The contributions are not

huge, but looking at 2004’s Olympic final and 2012 Olympic trials, the differences are so

small that the tiniest of advantages that are truly modifiable are instrumental. A simple

summary is good arms allow for relaxation and the right tuning of the body, but they are

complimentary and no bench press program is going to get you faster.

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Adarian Barr: This is a "how" issue:

1. Arm range of movement at the shoulder joint is important not just swinging.

2. The greater the range and the speed the faster you can sprint.

3. The timing of the movement is even more critical. The wrist should be the focus of

the movement and driven forward. The wrist should go top of the head when

coming out of the blocks and come cheek to eyebrow height when at speed instead

of the hands being swung back and forth or the elbow down and back.

4. The wrist movement creates a block at the shoulder joint which leads to vertical

impulse or increase in flight time and the speed the distance is covered.

James Smith: Biomechanically, the arm action generates counter rotational forces relative

to the rotation that occurs about the hips resultant of the stride. This plays a role in both

stabilizing optimal posture and momentum. As hip rotation can provide incremental

increases in stride length, via extending the horizontal distance of the knee relative to the

midline, it then follows that the influence of arm action on hip rotation also influences stride

length.

Experientially, I have yet to work with, consult, or observe a sprinter that has

optimal/efficient arm mechanics who demonstrates significant problems below the waist.

Clearly then, there is a relationship that exists and suggests that, from a coaching

perspective, emphasizing the optimization of arm mechanics ranks high on the list and this

is something that has been a constant in my career.

While optimal stride mechanics do not directly depend upon the biomechanical optimization

of the arm action (Bolt is actually an example of this due to the excessive flexion about the

elbow that occurs in front and what I believe influences his excessive shoulder elevation)

there certainly is no good reason not to make it a priority for sprinters.

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Q7. Does the action of sprinting involve more of a pushing action or a pulling

action against the ground?

Dan Pfaff: I am with Geoffrey Dyson and Tom Tellez on this one, it is a push.

Jimson Lee on Peter Weyand: Conceptualizing steady-speed sprint running as either a

push or a pull is not scientifically sound. Furthermore, this conceptualization could easily

lead coaches in unproductive and potentially nonsensical directions. This follows from the

negligible contribution of the pulling and pushing forces (i.e. horizontal) to the total external

force requirement for sprinting. Once a runner is up to speed, nearly all of the ground force

required is vertical in orientation while very little is required in the horizontal direction. This

somewhat non-intuitive observation is a direct result of how well runners conserve their

momentum and forward velocity from step to step once they are past the acceleration

phase of a race.

Our precise measurements of the ground reaction forces applied both in the horizontal and

vertical directions on our treadmill in the laboratory that agree well with force plate data

from over-ground running illustrate this. These measurements show that during sprint

running at near-constant velocities, the horizontal (i.e. pushing and pulling forces) ground

reaction forces comprise very small portion (i.e. 2-10%) of the total ground reaction force

required6. This percentage may be slightly greater when speed is more variable, when

running into a head wind and in truly elite sprinters who have to push against slightly more

air resistance. However, regardless of what the small variations from these values might be,

the essential conclusion is unchanged – steady-speed sprint running requires the application

of large forces downward and directly into the running surface.

This critical concept has come out of the classic work of Giovanni Cavagna and Dick Taylor1,

2, 4published in the 1960s, 70s and 80s that nicely demonstrated that the net requirement

for mechanical work and forward propulsion once a runner gets up to speed is negligible.

Because runners maintain their forward momentum so effectively, they do not need to

either push or pull horizontally while on the ground. They simply need to hit the ground

hard enough in relation to their body weight during brief foot-ground contact periods to get

back up into the air.

Kenta’ Bell: As I mentioned the hinge that swings big doors earlier the last thing you

want to do to any hinged door is pull against it. our mechanical hinge/lever system was not

designed to pull. We are designed to push, extend and retract. We are an advanced

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performance machine. Pulling, scraping, sweeping and pawing should be left to garden

tools.

Carl Valle: Hard to say contributions but both forces are happening since the back swing

has some forces horizontally but the primary influence is hip extension and knee extension.

Storage of ankle elastic forces from the Achilles is a factor, but what you see in the air of

toe off is just recoil, and not active contribution. The same with some hip extension we see.

The body is a series of reflexes and athletes and coaches should take lead from Tom Tellez

and not overthink things as this is happening so fast you can do much but let it happen. Or

job is to control what is likely to be not over-coaching or over-trying, and let mother nature

take over. I don’t know if central pattern generators are the reason running just happens

but if you can’t augment the action leave it alone and look for advantages one can improve.

We laugh at people doing dated training or would find someone training for height to be

stupid but artificial interventions are sometimes that foolish. Good sprinting action comes

from good coaching and talented athletes, and tinkering with it beyond addressing core

concerns has yet to be proven. It’s better to exhaust the known ways to be successful

rather than explore unknown areas and leave the obvious on the table.

Adarian Barr: Pushing action through the ground instead of against the ground or pushing

the ground should be the thought process when applying force. The force applied has to be

maintained through the ground contact period, which means push through the ground.

James Smith: We may consider the biomechanical data as well as the tactile interpretation

and, in most scenarios, the concept of pulling just doesn’t apply. That being said, one must

exercise caution in overstating the act of pushing.

We know that the predominance of applied force occurs in the horizontal direction during

block clearance and early acceleration. Then, as the athlete transitions to the upright

position the lion’s share of applied force shifts to the vertical direction. In this way, one may

state that the start and early acceleration are more pushing efforts which then transition to

stepping down (both actions are substantiated via the tactile based feedback of any

accomplished sprinter). At no point, however, do I believe it makes theoretical or practical

sense to conceptualize or cue ‘pulling’.

As a coach, and someone who is not yet defeated by time (in so far as I am still able to lead

by example- just not at world class speeds), I see no practical relevance in the concept of

pulling. I state this because, conceptually, pulling does not imply a time sensitive impulse. I

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believe that an athlete cued to ‘pull’ will invariably lower their hips, make ground contact

further in front of the hips, lengthen the ground contact patch, exacerbate backside leg

action (kick out the back), and ultimately run slower.

As previously stated, I would not suggest swinging the pendulum too far in the other

direction via emphasizing pushing. While the actual feeling of starting and accelerating is

pushing I would caution coaches to choose their verbal cues carefully in order that they,

first and foremost, resonate with the athlete as well as bare mechanical relevance to what

we already know about the sprint action.

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Jimson Lee's references used in Peter Weyand's research

1. Cavagna, GA, Sabiene, FP, and Margaria, R. (1964). Mechanical work in running. J. Appl.

Physiol.19, 249-256.

2. Cavagna, GA, Heglund, NC and Taylor, CR (1977). Mechanical work in terrestrial

locomotion: two basic mechanisms for minimizing energy expenditure. Am. J. Physiol. 233,

R243-R261.

3. Mann R, Sprague P. (1980) A kinetic analysis of the ground leg during sprint

running. Res Q Exerc Sport. 51(2):334-48.

4. Taylor, C. R (1994). Relating mechanics and energetics during exercise. In: Comparative

Vertebrate Exercise Physiology: Unifying Physiological Principles, edited by J. Jones. San

Diego, CA: Academic, pp. 181-215.

5. Weyand PG, Sternlight DB, Bellizzi MJ, Wright S. (2000). Faster top running speeds are

achieved with greater ground forces not more rapid leg movements. J Appl

Physiol. 89(5):1991-9.

6. Weyand PG, Sandell, RF, Prime, DNL, Bundle MW. (2010). The biological limits to running

speed are imposed from the ground up. J Appl Physiol. 108: 950-961.