The Approach

This is a forum to discuss advanced pole vaulting techniques. If you are in high school you should probably not be posting or replying to topics here, but do read and learn.
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Re: The Approach

Unread postby chasing6 » Tue Mar 09, 2010 5:21 am

altius wrote:There should be NO counting in the run up!


I seem to remember reading something about counting in BTB2, but I don't have it on me to reference. What is the downside to counting? I distinctly remember reading about using the "1-2-3-Plant-2-3" to teach proper timing of the plant, and faintly remember reading something about carrying that over into your full approach. Please correct me if I'm wrong.

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Re: The Approach

Unread postby tsorenson » Tue Mar 09, 2010 1:29 pm

Chasing6, you are right. B2B2, p. 116-117 and p. 136 talk about this issue, basically stating that Alan teaches beginners to count their steps to build proper rhythm and cadence and then discourages it once they progress from cognitive mode through the associative stage, into the automatic stage.

Personally, I always teach beginners to count steps in order to learn the precise rhythm of a consistent runup. This is also the reason I encourage vaulters to count every step rather than only lefts (or rights).
I use a counting method I learned years ago from Don Hood, it helped me improve by 18" the first year I used it (I used to have a lot of issues with run consistency). I believe it is similar to what Rick was suggesting, and what Alan suggests in BTB, breaking the run into various phases:
Here is the pattern for a seven-left-approach:

-Always start with "1-2-3-4" (four relaxed, high knee strides to get you moving and break inertia smoothly and consistently...this is usually the part of the run that is most irregular for vaulters so it is important to stay relaxed with good posture)

-Then you punch it and go into your acceleration phase "1-2-3-4-5-6-7" (this phase changes depending on the length of the run; 5 lefts is "1-2-3-4-5", 8 lefts is "1-2-3-4-5-6-7-8-9", etc.)

-The last phase is "start-curl-press" (or something similar) over the last three steps. Some kids prefer "1-2-3" or "plant-2-jump" and I let them use whatever they like as long as they are planting early and accelerating through the takeoff. When I teach it to young vaulters, I am flexible in what they want to "say" as they count and even if they prefer to build rhythm by using their breathing as their feet strike the runway.

The beauty of this counting is how quickly vaulters will achieve a consistent rhythm in order to gain a confident takeoff, increasing cadence, and an early plant. It also is helpful that the three phases stay the same no matter what length run you are using (the only exception is a three-step or less, then you don't really have an acceleration phase).

I can see Alan's (and other's) point about getting experienced vaulters to focus more on other aspects rather than wasting concentration on counting the run, but with most HS vaulters (and even many college vaulters) consistency on the runway is the biggest issue. I still count my steps and find that it has become so automatic that it doesn't require much concentration at all. One thing I know for sure is that I can always tell when a young vaulter doesn't count their steps because their run is all over the place and they usually plant late.

Tom

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Re: The Approach

Unread postby vault3rb0y » Tue Mar 09, 2010 3:39 pm

I believe the relaxation is the key. Everything else revolves around building your run up while relaxed. Telling kids to sprint and then finding where they are at full speed could be misleading. 99% of vaulters, especially young vaulters, will try to force their run-up speed and end up tense/inconsistent with their steps. Unless they can come out of the blocks relaxed and without trying to force their speed, they will have a very hard time with it during the vault.

Counting steps can also make vaulters feel like they have to "telegraph" their runs and control their steps, when they should just relax and let themselves run naturally. But until vaulters have the internal metronome in their heads, they need a way to time their drop and plant correctly.
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Re: The Approach

Unread postby chasing6 » Tue Mar 09, 2010 7:21 pm

tsorenson wrote:Chasing6, you are right. B2B2, p. 116-117 and p. 136 talk about this issue, basically stating that Alan teaches beginners to count their steps to build proper rhythm and cadence and then discourages it once they progress from cognitive mode through the associative stage, into the automatic stage.


Thanks, I knew it was in there somewhere. :yes:

tsorenson wrote:I can see Alan's (and other's) point about getting experienced vaulters to focus more on other aspects rather than wasting concentration on counting the run, but with most HS vaulters (and even many college vaulters) consistency on the runway is the biggest issue. I still count my steps and find that it has become so automatic that it doesn't require much concentration at all. One thing I know for sure is that I can always tell when a young vaulter doesn't count their steps because their run is all over the place and they usually plant late.

Tom


I've had the same experience, counting my steps from the first day on the runway (13+ years ago) has made it second nature. The only part that i have to think about is which number to start on (I count down) when I move to a longer/shorter run. The rest is habit.
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Re: The Approach

Unread postby altius » Tue Mar 09, 2010 9:58 pm

Never forget that skilled performance is AUTOMATIC/NON CONSCIOUS behaviour. Thinking - and counting - get in the way. Beginners do need to count but using the simplest possible pattern as detailed in btb They especially need to count the 3 -3 in the last six steps because the movements of the pole must be absolutely precise at this time and be synchronised with the steps to put the pole in EXACTLY the right place in the penultimate step. Anyway it is all there in BTB as tsorensen indicates. Nothing a few thousand reps cant cure - and that is the secret - if you dont do at least one full run session THROUGHOUT the year do not bleat about an inconsistent run up. It MUST be given priority over weight training/cross country running and even gymnastics.
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Re: The Approach

Unread postby dj » Sun May 23, 2010 11:25 am

good morning,

Alan...Never forget that skilled performance is AUTOMATIC/NON CONSCIOUS behaviour.


vaulters FIX THE RUN!!!!!!!!!!!!!!!!!!!!!!!!!

stop using jr high thought processes... like "I came out too fast and didn't have anything at the end."

stop coming out natural and fast... but hit ting out at the mid... and think it was because you came out toooooooooooo fast!!

NOT..

come out fast and natural.. just adjust your start point to match the good speed when your pumped..

RUN OUT OF THE BACK (start)

AND STOP USing SHORT RUNS AS YOUR EXCUSE.. every world class vaulter should be at 20 strides.. 9 lefts is still "safe".. challege yourselves..

!!!! learn why you screw up on longer runs.. and fix it...

COME OUT OF THE BACK...... GET YOUR FEET DOWN........ PLANT BIG....

GAME OVER..

dj

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Re: The Approach

Unread postby dj » Thu Jul 22, 2010 7:11 am

good morning,

Over striding is the greatest issue affecting the Approach... Proper pole carry is an absolute.. but there is an "Equal and Opposite" action/reaction..

if you over stride you will "shift the pole" for balance.. once you "shift" the pole you will over stride to "find" the balance..

A vaulter should "position" properly at the start... lean and come our naturally.. accelerate to the 6 step "MID", begin the pole drop, increase the frequency to a "on time" high, out, drive through, “impulsed” (jump) plant.

here are two articles.. hopefully they will give some important info…


Glen Mills
NSA INTERVIEW



Thanks to those races, a surname right out of a Hollywood scriptwriter's textbook and the general application of good-natured showman¬ship before, after and even during his races, Bolt is also known to just about every kid who has access to a playground, television or YouTube. Has the sport ever had a bigger star? Has it ever had a better opportunity to draw in youngsters?

Gradually, the world is also learning about the "not as easy as it looks" back-story to the Bolt phenomenon: the hotbed of sprinting talent that is the Caribbean, his personal determination and dedication, his link with the IMF High Performance Training Centre (HPTC) at Kingston's University of Technology in Jamaica, and the patient expertise of veteran coach Glen Mills, who has guided his career since 2004.

The credentials and reputation of Mills, who, incredibly, has been coaching since the age of 14, were already well established before he hooked up with Bolt. His coaching education included courses staged by the IMF Regional Development Centre in Puerto Rico and the International Olympic Committee. He has led Jamaican teams to international competitions, coached a number of top sprinters from the Caribbean, including 1987 world championships 100m silver medalist Ray Stewart (JAM) and 2003 world 100m champion Kim Collins (SKN), and he is currently the main coach at the IMF HPTC in Kingston.

But with the success of Beijing, Mills' own story is becoming more widely known and recognition has followed. Among his most recent awards was the "Coach of the Year" presented by his colleagues in the North American, Central American and Caribbean Track and Field Coaches Association (NACACTFCA) in October 2008.

Insight into Mills' thorough approach and his relationship with Bolt is provided by his story of how in 2007 he wanted Bolt to train for the 400m in order to better prepare for his pet-event, the 200m. According to Mills, Bolt, wanted to change his focus to the 100m. "I told him that if he broke the Jamaican record in the 200, I would allow him to run one 100," says Mills. "He did the training as asked, broke the record (running 19.75) and then he said: 'You've got to keep your promise'.

Bolt ran his first professional 100m that year, clocking 10.03 seconds. "After that there was no stopping him," Mills said.

To learn more about his methods and thinking, NSA sent the Director of the ROC San Juan, Lenford Levy, to speak with Mills in his Kingston office.

NSA: When did you discover that coaching was "your" profession?

MILLS: Some 40 years ago. I found a passion for coaching and have worked on developing myself, becoming more educated and qualified, from that time until now. My sub¬stantive post or profession is that of Sports Administrator. I have worked here at the Institute of Sports for over 20 years. Coaching is the other half of my life where I enjoy coaching track and field after work and sometime during work time.

NSA: As you have obtained formal coaching qualifications, how do you judge the usefulness of such programmes for your work now? What recommendations would you make for improving them?

MILLS: I did several courses with the IMF at the ROC in Puerto Rico and with the lac. These were very informative. One that really stands out is a course I did in Mexico. It was held over an extended period of two months, after which I received a Diploma. It was conducted by a number of professors, mainly from the former Eastern Bloc countries, who really went into great depth about the event specifics and the supporting sciences.

I have not been on an IMF CECS course recently. However I have spoken to coaches, including my assistant, who have been and they all seem to have come away with a wealth of information. Based on my own experiences, my only recommendation would be for these courses to be held over an extended period, so that the coaches can go into more depth in the event specifics and the related sciences.

NSA: How have you developed your coaching eye for sprinting?

MILLS: I have always been fascinated with speed, running mechanics and so on. I think that what I learned in Mexico about the physical characteristics of the human being, agility and coordination has helped. There was one unit on Sports Medicine, where we looked at talent identification and some of the characteristics necessary to perform well in the sprints in comparison with other events. That knowledge, which included biomechanical analysis of the movement of top-class runners, has guided me over the years. I personally believe that a coaching eye is part of a gift that is unique to a ,person. Over the years I have been able to use that, along with knowledge gained from courses, books, etcetera, to identify athletes I think will go far in sprint¬ing. It's probably difficult to relate outside of the scientific principles, but one has to approach it with an open mind because you could lose a good sprinter or athlete because he does not fall within the norm --- you sometimes have to think outside the box.

NSA: In Usain Bolt you are training the most successful sprinter for years. How have you evaluated his technique?

MILLS: Usain is an extremely gifted athlete. When I started working with him, one of the things that stood out like a sore thumb was his poor mechanics. He was running behind the centre of balance. This resulted in a negative force against his forward drive and it was affecting other areas. For example, his body position put pressure on his lower back and there was a continual shift of his hip girdle and a pull on his hamstring. He was continually having hamstring problems and my assessment was that one of the things that contributed to it was his poor mechanics. Our first task was to get him to run with his upper body core in line with his centre of mass or a forward lean of somewhere around 5-10°. We set about doing drills then we took videos of his workouts and broke them down on the screen in slow motion to show him exactly what he was doing. I would draw diagrams and show him the position that we are working to achieve. Part of his poor mechanics was because he was not able hold the sprint position during maximum velocity running, so we had to do an intense programme to develop his core strength. In Beijing he showed a mastery of the technique that we had been working on, but the transformation took two years. Athletes tend to reverse to their old habits when put under pressure or when running at maximum velocity. Like helping an actor learning a part, coaches have to continuously react and replay and redo the drills, getting the athlete to run over and over in order to break habits, both psychologically and physically, and get into the right running technique.

NSA: Can you briefly describe the most important elements of a good sprinting technique? We know that body position, ground contact phases, recovery mechanics and arm action all have to work together, so do you have a specific model in your mind?

MILLS: All the points I just mentioned are the foundation of developing sprint technique, but the key is how you get that athlete to execute all of them accurately. He or she could be doing all, or most, or just some, but without perfect co-ordination or timing in the execution. One key is to establish a good body position in sprinting so that the athlete is able to maintain the stride length and keep ground contact or ground time short after having achieved maximum velocity. Here we believe that the development of the hip flexor to coincide with the strong upper body, or core, plays a great part. Once the athlete's stride length reduces, everything is going to be negative or impact negatively in the ground contact and recovery mechanics. A collapse in technique and poor execution will then lead to a rapid deceleration process and a disappointing overall performance.

NSA: To what extent must an athlete's technique adapt to the different phases of the race?

MILLS: The techniques for starting, for the drive phase, for the transition from the drive phase to acceleration, for maintaining top speed and then for reducing the effects of deceleration are different. The athlete must be able to adjust the technique to the different phases without loss of time. If, for example, when the athlete switches coming out of the drive phase into the acceleration phase and the technique is not correct he can lose significant momentum. Even if he was in a striking position during the drive phase, you will see the field leave him and then he will have to spend time to develop the momentum to get back to top speed and into the race. In the 100m, athletes usually run out of time when something like this happens.

NSA: How do you distinguish between the different race phases? What is their approximate ratio?

MILLS: I approach it according to the individual. The athlete himself and his strengths and weaknesses determine the length of the different phases. For instance, the length of the drive phase is affected by how much strength the athlete has to stay in the crouch position while developing maximum power. If the athlete does not have the strength to carry the drive phase long enough then it has to be aborted so he can go into the transition earlier. If he is strong, like an Asafa Powell, and has an effective technique, he can carry this phase very long. I adjust the phases to suit the athlete's strong and weak points, whether he is an explosive runner from the blocks or one with better top-end speed. If, for example, you were to say that the drive phase is 25m and stick to it then you would have problems with an athlete who may have a variation. Certainly an athlete with good top ¬end speed can use a shorter drive phase, because the chances are he develops top speed later and will be able to maintain maximum velocity longer in the last third of the race than the explosive starter. Of course, if the athlete has deficiencies in various areas then you have to correct them while you adjust the race phases, but you cannot adapt him to a phase that he is not able to execute.

NSA: How do anthropometrics influence the technique?

MILLS: Every athlete has a natural pace, so you start with his natural pace and look at the deficiencies that exist.. For example, stride length. If an athlete has the necessary reach in terms of physical structure, say someone who is six feet (1.83m) tall but is taking strides that are shorter that he should, I try to analyze what are the areas that are contributing to the situation. It is usually the strength of the various muscles that carry out the movements and therefore we must work, especially in the off-season, to change the athlete: 1) to develop the strength needed and 2) to improve the stride pattern with specific exercises. For example, we determine the athlete's natural stride and then we use markers to set out stride length. In each exercise we lengthen the marker in a very moderate way, maybe by half inch to one inch. The athlete executes the run trying to extend the stride length to meet the markers. However, he must ensure that he is not over-striding to meet the marker, hence he has to get his knee to the required height, the heel recovery must be correct, etc. Once athletes start doing that correctly, they tend to open up more and execute a longer stride length. They will be able to maintain maximum velocity, without over striding. We have found that if we can extend the stride length and maintain the correct velocity it will improve the time significantly. We also try to develop the athlete both mentally and physically to be aware of maintaining their stride length even when fatigued, especially in the 200m. You can only carry top speed for maybe 50-60m, but how you maintain the stride length will determine your overall time.

NSA: Do you think that tall sprinters have an advantage? What would you recommend in order to adapt technique and race distribution to the given anthropometrics?

MILLS: They only have an advantage if they can master the technique and the different stages. With sprinters who are explosive, their advantage comes in the first half of the race; the taller sprinters tend to be at a disadvantage in the first half of the race. If a shorter sprinter is able to maximize his\her stride length in the second half it is difficult for them to be beaten. However, most of them tend to tighten up in the maximum velocity phase or once they feel the presence of a taller sprinter. This is why athletes who have good top¬ end speed win most 100m races. There is a balance between the tall and the short, but a lot of it is lost, especially for the short sprinters, in the psychological preparation that tends to affect them in the competition itself. The distribution is also important because if the athlete achieves maximum velocity too early it increases the period of deceleration. The aim for the explosive sprinter is to distribute their early acceleration so that they reach maximum velocity later in the race, without sacrificing the advantage of being explosive at the start. Working with the athlete on a one on one basis, the coach with his experience and constant study of the athlete and his or her race pattern would determine the optimum
point at which he would want the athlete to achieve maximum velocity. He then works to see how long that athlete can maintain that velocity. That would significantly help the ath¬lete in terms of adjustment and adaptation to running the 100m or 200m, because if the curve is too steep then it is going to keep coming down on the deceleration phase.

NSA: What type of strength training do you see as important for the 100m and 200m?

MILLS: Strength is one of the hallmarks in sprinting and therefore it must be developed. However, I believe that there are two types of strength: the static and the dynamic strength. I think athletes tend to depend too much on the static strength and that dynamic strength is one of the greatest areas of deficiency in most runners. They are all bulked up and big and powerful from the weight room, but they neglect the dynamic strength, that is the strength developed in resistance training, ply¬ometrics and so on. We find with our sprinters that we get far better result when we almost have a fifty - fifty split between static and dynamic strength training.
NSA: How do you manage to keep the balance between speed endurance and pure speed work, so that the athlete is fresh and explosive?

MILLS: Speed endurance and pure speed have to work hand in hand. People tend to separate them and do speed endurance as a single component and then do explosive speed training as a single component. A lot of time we hear sprinters say that they have not started speed work yet, which means that they have been doing speed endurance work. My philosophy is that the two should run concurrently and that coaches should try to develop a balance. To keep the athlete fresh and explosive, the load has to be slightly reduced as you go to high velocity and high quality performance in training, the work that is done in the last part of the competitive period leading up to the major completion. A greater degree of rest is required for recovery and explosive training must be greatly reduced to maybe once or twice per week and a recovery should not be less than 36 hours, 48 hours would be even better. A lot of coaches feel that if you reduce the workload too much in terms of training time the athlete will lose something, but that is not my experience.

NSA: Successful sprinting is very much dependent on the right motivation. How do you motivate your athletes? To what extent do you involve them in specific coaching decisions?

MILLS: We treat motivation as one of the elements of training, so we train the mind concurrently with the body. I do a lot of talking in training on motivation individually and collectively, especially in between workloads, during recovery time. Short, quick words of inspiration, directive thought process, getting the athletes' minds to focus on what the goal is, pulling on their inner strength and so on. There is time allotted for motivation at the training site and within the training programme that lays the foundation for other motivational talks outside of the training. These are not only spoken to but are put into situations where the athlete's mettle and mental strength is tested, for example, we tend to look for the stiffest competition to face the strongest opponent --- our motto is that you have to "learn to lose in order to learn to win," When you lose you understand why you lose, you take it with grace and it does not defeat you, because you know that it is part of the process of winning. We believe if you are afraid to lose then you cannot win, because the subconscious is always going to be questioning your competence to win. You must be consciously able to confront it and use your positive approach to overcome it. Otherwise it will become the dominant factor in your sub¬conscious and become a part of your con¬sciousness. When fear becomes a part of your consciousness, you will find that you get extremely nervous and your neuromuscular system loses a high degree of energy, almost paralyzing the limbs, The quick impulses from
the brain to the muscle are crucial for explosive sprinting. Once the brain becomes distracted by doubt and nervousness the impulses are not going be as positive and strong as they should be and this lends itself to subpar performances.
NSA: Can you give our readers some advice on 'Talent Recruitment' and what indicators to look for in an up and coming sprinter?

MILLS: First, look at the physical attributes of the athlete: physical structure, agility and coordination. Coaches should look for athletes who they as coaches can contribute more to their development rather than athletes who already have the physical development. Then look at the cadence. Sometimes the athletes in the middle positions of a race have superior cadence and are held back a little because the coordination is poor and they are not able to execute the stride pattern. In recruiting talent you cannot start at the top, you have to look beyond. I have spotted a lot of talent who finished down the track but are not yet developed. Some guy that finished last might have been the leader for the first 30m of the race. Nobody looks at him because he finished last. But his physical structure and the fact that he had the speed to be leading are factors that you cannot overlook. Question the athlete about his preparation: How long have you been training? How much training have you done? A youngster might say, 'sir I am only training a month, or a week' while the winner of the race has been training for a whole season. You could take such an athlete and train him and see significant improvement. He may become a champion, Another thing to look for is the bounce. Look at the heel contact with the ground, people who tend to walk with less heel contact tend to possess a lot of speed and have a better mechanism for lifting their knees and recovery. This does not mean that a man that runs on his heels will not run fast, but it is something you can look for. Finally, look at the youngster to see if he is aggressive in his movements. These are some of the general things that can indicate talent.

FROM: IAAF NSA 1-2009
________________________________________

Ross Dunton
coachr880@bellsouth.net


What Contemporary Research Tell us about Sprinting
Illinois Track and Cross Country Coaches Association Clinic
Ken Jakalski
January 12, 2002

Reconsidering the Conceptual Paradigm of Running Mechanics

The history of speed training makes it clear that our philosophical approach changes with the current thinking of the time. For example, several years ago, coaches believed that the only way to increase speed was to increase stride length. Indeed, stride length is a function of running speed, since stride lengths do increase as our speed increases. The natural way for a runner to increase stride length is for him or her to increase the force against the ground in each driving phase. This, of course, requires increased leg strength.

Then, we began almost two decades of sprint training that emphasized what is now referred to as neuro-biomechanics. This approach challenged the commonly held notion that stride frequency was too difficult to improve, and noted that, of the two factors, stride length/stride frequency, frequency was actually more important. The training approach today focuses on reducing the time it takes to get necessary force into the ground. The goal is to increase stride frequency and reduce the time it takes to recycle the leg.

To this end we designed drills to train athletes to place their limbs in more appropriate positions to improve the rate of force development. Since the ground phase was dictated by ground preparation, the key was to generate high speeds backward to minimize breaking forces and maximize propulsive forces. The secret seemed to be the ability to generate high negative thigh speed, or what came to be known in coaching circles as negative vertical velocity.

Unfortunately, the drills we’ve designed have been based more on coaching insight and observation than on hard science, and it’s clear that the questionable carry-over of these drills to actual sprinting has left many coaches and runners frustrated. I have watched many colleagues teaching dorsi-flexion, pawing, clawing, fast foot, stepping over the opposite knee, appropriate arm carriage, etc. only to observe with dismay that these movements don’t appear to be repeated when their athletes begin sprinting. What’s the problem here? Insufficient time to fix these new patterns of movement? Poor coaching of these techniques? Inappropriate cues? Improper drills for appropriate mechanics?

My contention, based upon a wonderful opportunity I had to study over thirty years worth of locomotion research under the direction of renowned Harvard physiologist Peter Weyand, is that we may very well be attempting to make modifications to non trainable entities. I first began to consider this possibility when conventional speed training could not explain to me how it was possible for an athlete without feet to dorsi-flex, or arms to aid in propulsion, could run 22.94, which is exactly what World Paralympic Sprint Champion Tony Volpentest did in Lisle four years ago!

We believe that athlete’s faster muscle fibers can improve stride frequency by reducing the time spent on the ground and in the air. In fact, reducing ground time and air time has been the basic approach to speed training since the early eighties. However, what if we discovered that the mechanical energy to reposition the free swinging limb is actually provided passively through elastic recoil and energy transfer between body segments instead of power generated within muscles?

If this were the case, if muscle speed has little effect on minimum swing time, then training to improve stride frequency, what we now refer to as maximum velocity mechanics, would be of little value.

If frequency is revealed not to be a contributor to faster top end speed, what is? Stride length must be critical. But how do athletes increase stride length? One way to achieve longer strides is to apply greater support forces to the ground. This makes sense, since we know that, at any speed, applying greater force to oppose gravity will increase a runner’s vertical velocity at take-off. As a result, the forward distance traveled between steps will increase.

This was the Harvard researchers’ hypothesis: that greater ground forces rather than minimum swing times enable sprinters to achieve faster top end speeds. In this process, the team re-considered the elementary mechanics of running. First, they explored the possibility that runners reach maximum velocity simply by taking more frequent steps. Next, they explored their original hypothesis, that speed could be achieved by the athlete increasing mass specific force to oppose gravity during the time the foot is in contact with the ground. Finally, they attempted to take into account the fact speed might be achieved by increasing the forward distance the body moves during this contact period, which is referred to as contact length.

The Harvard team expected to find that top speed was indeed more a product of forces applied to the running surface rather than increases in step frequency or contact length. Why did they feel this would be the case? For one, swing time comprises the majority of total stride time, and is the primary determinant of the frequency of a runner’s steps. However, because the range of stride frequencies used by runners at different speeds tends to be narrow, the researchers expected little variation in step frequencies at top speed.

This similarity in step frequency is a difficult concept for most of us to grasp, since video analysis seems to reveal some fundamental yet critical movement “commonalities” consistent at high speed running, and that these commonalities indicate optimal positions of the leg during the recovery cycle. As a result of these observations, we concluded that the fastest sprinters in the world actually reposition their limbs appreciably faster than sub-elite sprinters, but this is not the case.

Second, contact lengths at high speeds do not vary significantly, yet faster runners still take considerably longer strides. Length of contact was clearly not a factor. Even though it would seem as if sprinters would benefit from additional time they have to apply force, but attempting to increase stride length through unnaturally longer steps is actually mechanically inefficient.

So what did the Harvard study reveal?

The more rapid increases in stride frequency as athletes approach top speed are achieved through reductions in both the contact and swing times that make up total stride time. The time when neither foot is on the ground—the aerial time—also decreases as top speed is approached.


Thus, the traditional concept of speed being the product of reduction of the time spent on the ground and in the air was correct, but the process by which this occurs never considered running mechanics as a function of speed—at least not the way the locomotion experts have been understanding mechanics. In other words, we believed that specific limb movements associated with high speed running were trainable entities that could impact upon performance. This is simply not the case.

Faster runners apply greater forces during briefer contact periods, but because of the narrow constraints in the minimum swing times and maximum contact lengths of sprinters, speed is conferred predominantly by an enhanced ability to generate and transmit muscular force to the ground.

The Conclusion
Of the mechanical means by which runners can reach faster top end speeds, the Harvard team found that runners rely on stride frequency to a limited extent, support forces predominantly, and contact lengths not at all.

The mission statement of previous speed programs was to reduce the time spent on the ground and in the air. The Faster Than Gravity mission statement, at least based on the new paradigm proposed in the Harvard study, is to alter support forces applied to the ground by one tenth of one body weight, which will be sufficient to alter top speed by one full meter per second!

The Limits to Top End Speed
Top speed is reached when increases in speed and decreases in foot ground contact times reduce effective aerial times to the minimum values, providing sufficient time to swing the leg into position for the next step. In other words, Leigh Kolka’s theory that we can sprint as fast as we can put the free swinging limb in front of us was indeed accurate, but for reasons that, at the time, none of us truly understood.

The fastest runners do have faster muscle fibers and do have great muscular power available to reposition their limbs, but the reality is that they reposition their limbs little or no faster than average and slow runners do.

Activation of the flexor muscles and tendons that reposition the limb as a runner swings his leg is considerable at high speeds, but this activation likely occurs to increase the storage and release of mechanical energy in the oscillating limb rather than to generate mechanical power chemically within these muscles.

Once again, faster muscles fibers confer faster top end speeds not by decreasing minimum swing times, but by increasing the maximum rate at which force can be applied to the ground. An enhanced ability to quickly reposition their limbs in the air is not the reason why sprinters achieve faster top end speeds. They are simply applying greater support forces to the ground.


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