mechanics and development of single leg vertical jumping

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  • 5/21/2018 Mechanics and Development of Single Leg Vertical Jumping

    Mechanics and Development of SingleLeg Vertical Jumping

    By Joel P. Smith, MS, CSCS, USATF I

    Cover By Jake Clark

    Introduction

    This report is designed to be an extensive resource regarding the development of single leg leaping

    ability. Athletes from all disciplines will be able to benefit from the contents within. This report will alsoprove incredibly useful to track and field coaches as a biomechanical reference and training toolbox

    for those athletes involved in the jumping events of track and field. The four parts of this report are as

    follows. I hope you enjoy the information, and that this takes you to the next level of your athletic

    performance!

    Chapters

    Part I: Overview of Jumping Biomechanics

    Part II: Elements of Single Leg Jumping

    Part III: Physical Qualities of a Single Leg Jumper

    Part IV: Exercises for Single Leg Jumping Developmen

    http://www.facebook.com/#!/joel.smith.129http://www.facebook.com/#!/joel.smith.129
  • 5/21/2018 Mechanics and Development of Single Leg Vertical Jumping

    Part I

    An Overview of Jumping Biomechanics

    Exhibit A: James White

    This report is designed to give you, as an athlete, a more in depth view of how to improve your single leg

    vertical jumping ability. It is designed for a variety of readers; the athlete proficient at jumping off of twolegs who struggles off one, the athlete who is already good off of one, but wishes to get better, a track

    and field jumper, or a coach hungry for new information.

    Jumping off of one leg can be tricky business, especially if your body is not really used to doing it. Many

    athletes want to have that pop off of one leg that allows them to get up quickly on a fast break in

    basketball to throw a nasty dunk down with authority. Despite their desire to do so, many athletes who

    are good at jumping off of two legs will just struggle getting up at all off of one leg and find themselves

    frustrated as to why they arent good at it. To help remedy this scenario, this article is designed to be a

    comprehensive resource in terms of what exactly goes into being a good single leg jumper.

    Being a track and field coach, I have worked with a lot of natural two leg jumpers and have been

    assessed with the task of turning them into one leg jumpers for the sake or long and triple jump. I feel

    that my experience with biomechanics in graduate school, my education on how track coaches teach the

    motor learning progression of single leg jumping, and then my own experience training two leg jumpers

    into one leg jumpers has given me a nice working knowledge of how to help any aspiring athlete increase

    their vertical off of one leg.

    I feel that there are three basic reasons that athletes tend either have or do not have single leg jumping

  • 5/21/2018 Mechanics and Development of Single Leg Vertical Jumping

    ability. These three reasons are: biomechanics/technique, muscle-tendon stiffness and motor

    learning/practice. This article will go into each of these topics in depth, but in a way that is easy to read

    and understand. Exercises designed to assist these factors will be given at the end of the report. If you

    dont want to get into too much heavy reading, I have summarized the main technical points of jumping

    at the end of part II. Part IV is going to be where many of the corrective exercises for vertical jump off of

    one leg will be found, but in order to reap the maximal benefit regarding the increase of your one legjump, you will want to at least scan through the entire report.

    The biomechanical factors of single leg jumping will be the first aspect covered. If you are someone

    reading this who just feels awkward when performing a single leg jump, this section will help you learn

    what the final product should work in getting up off of a single leg. Even if you feel your single leg jump

    technique is pretty sound, you still can benefit from a better knowledge of the exact biomechanical

    contributions to a good one leg jump. Finally, for any track and field coaches reading this, many of the

    concepts will be familiar, but you may find some concepts you were unaware of, and how to optimize the

    unilateral jump.

    Track coaches can use these principles to optimize their athletes technique and power

    Single leg jumping on the basic level is actually more dependant on technique rather than just raw

    power. It is typically a skill that most athletes either seem to have or do not have. It is not all that hard

    to turn a natural one leg jumper into a two leg jumper through strength training methods, but doing the

    reverse, turning a natural two leg jumper into someone good at jumping off of one can be a difficult

    process. Although complicated, jumping off of one leg helps athletes to take serious advantage of the

    horizontal speed that they can generate, and then turn that speed into vertical velocity. Jumping off ofone foot is a more efficientway for athletes to convert speed into vertical than jumping off of two feet,

    and often can be used to reach vertical leaps well into the 30s and sometimes 40s without having the

    large amounts of strength or power that their two leg jumping counterparts might have. So how exactly

    does single leg jumping work? Well first lets look at the basic principle that is a must for any athlete to

    get of the ground regardless of one or two leg jumping style.

    Lowering the Center of Gravity

  • 5/21/2018 Mechanics and Development of Single Leg Vertical Jumping

    No matter what your natural jumping style is: one or two legs, or even in a standing jump; you mustlower your center of gravity (COG) in order to propel yourself upwards. In case you didnt know, your

    COG is an imaginary point just a few inches below your belly button and in the center of your body, it

    represents the one point in your body where you would be perfectly balanced if it was suspended from

    an imaginary string.

    The center circle represents the COG

    It is not possible to jump up without first bringing the COG downwards. Like Newtons Law states, for

    every action there must be an equal and opposite reaction. If you dont believe me, then try this: Stand

    completely upright and see how high you can jump without bending your arms, back, legs or hips down

    at all. just try and jump without first moving downwards bybending your hips, knees, and ankles. It

    probably was not very high, maybe a couple of inches at best. In order to jump high, any athlete must

    learn to optimally lower their COG.

    Once the COG is lowered, there are two basic methods that an athlete can use to raise it upand achieve liftoff.

    The first way that athletes can achieve vertical displacement is through the power of the athletes

    muscles themselves. A standing vertical jump is a prime example of this. During a standing vertical

    effort, anathlete will lower their center of mass through the bending of the hips, knees and ankles. Since

    there is no momentum brought into the jump (other than the rapid lowering of the body which puts the

    stretch shortening cycle into effect and provides some loading on the tendons), it is primarily up to the

    power of the muscles to provide the force needed to get the athlete up in the air. It is for this reason

    that bigsquats in the weight room tend to equal pretty big standing vertical jumps. More muscle power

    outputmeans more vertical in this scenario. Dont get me wrong, having some serious power is pretty

    important for single leg jumping as well, but the correlation isnt quite as direct, you can have the power,

    but be unable to use it in a single leg vertical attempt.

    The second way that an athlete can get vertical is to use their body limbs as rigid levers in order to

    convert horizontal speed to vertical speed. In the early years of athletics, track and field pole vaulters

    used completely stiff poles in the pole vault event to launch themselves over a bar over 15 feet in the air.

  • 5/21/2018 Mechanics and Development of Single Leg Vertical Jumping

    Old School Pole Vaulting

    During running jumps, and especially during a running single leg jump, your leg is the pole! It converts

    the speed of your run-up into vertical. Look at the following pictures of two athletes in the plant phase of

    their jumps and you will see just what I am talking about.

    Running Double Leg Takeoff

  • 5/21/2018 Mechanics and Development of Single Leg Vertical Jumping

    Running Single Leg High Jump

    When looking at these jumps we can deduce a few aspects of running jumping in general:

    1.

    The athletes must position their limbs out in front of their center of mass to form the lever

    system which will give them vertical velocity. If you plant under (not in front of) your center of

    mass when preparing to jump, you are not going to project your body on much of a vertical

    angle (you will jump more out instead), unless your run-up is extremely slow. The faster you are

    running, the farther you will have to plant out in front of your center of mass to travel upwards.

    2.

    Athletes proficient at running jumps will lower their center of mass prior to takeoff. Different

    athletes will lower their bodies by different amounts according to the eccentric loading theycan handle and the design of their muscle tendon structure. There isnt an optimal amount of

    lowering for all athletes across the board.

    3.

    The knees of these athletes are not nearly bent to the point they would be if they were

    performing standing vertical jumps, they are much more rigid. The knees bend minimally

    because the athletes need to conserve the speed of their run-up when taking it to vertical. If the

    knees bend too much, the lever which the athlete is creating to get themselves vertical is now

    more of a noodle (even if it is a strong noodle) and wont help convert horizontal speed very well.

    Compare the factors that are involved in a running jump with a standing vertical jump. They are

    different motor skills. Here is a video of the levers involved in a standing vertical jump. Notice howmuch greater knee bend is present in the standing vertical jump vs. the running vertical jumps.

  • 5/21/2018 Mechanics and Development of Single Leg Vertical Jumping

    Standing Vertical Jump

    Some athletes are physically built to perform running vertical jumps better than others. For single legjumps especially, long legs in relation to torso are very beneficial, because this increases the length of the

    lever system in the jump. Another genetic factor that is going to determine the ability of an athlete to be

    successful in running jumps is the structure of their Achilles tendon. Research by Earp and colleagues

    (2011) showed some eye opening results regarding how the length of the Achilles tendon affects how

    force is produced and transmitted in the lower leg. Earp found that athletes who have shorter Achilles

    tendons will tend to do poorly when jumping from a standing position, but will be more powerful when

    performing elastic jumping, such as a depth jump.Athletes with shorter Achilles tendons will tend to do

    better respectively with jumps from a running start, and the more speed brought into the jump, the

    better. On the other hand, athletes who have extremely long Achilles tendons will do very well in their

    standing vertical leaps, but suffer when a running start is involved. I can personally attest to this research

    as seen this in my own athletes, and I will provide two examples below.

    A few years ago, I coached a girl (who was also the NCAA DIII national champion in the 55m dash) who

    had extremely long Achilles tendons and hit a 30.8 standing vertical off of my just jump mat. She could

    not manage any better jump height from a run-up. Conversely, I had a Swedish jumper recently with

    extremely short Achilles tendons. He managed only a 25 inch standing vertical jump, but yet he long

    jumped close to 23 feet (7 meters), and he was not all that fast either (11.75-11.80 in the 100m dash).

    You can also look at the legs of Stefan Holm and discover the same thing.short Achilles, a poor

    standing vertical (only around 24) and a HUGE running vertical jump. His short Achilles tendon allows for

    a brief, but powerful loading of force and makes his leg an effective rigid lever which propels him

    insanely high in a running vertical jump. The ultimate build for a running vertical jump off of one leg is

    one with a thin frame, very long legs and short Achilles tendons. Check out videos of world class highjumpers, and you will see what I mean.

  • 5/21/2018 Mechanics and Development of Single Leg Vertical Jumping

    Andrey Silnov: Explosive, Thin, Long Femur, Short Achilles = Single Leg Jump Machine!

    Now, just because you might lack the genetics to clear a high jump bar 2.30 meters over your own head

    doesnt mean that you cant improve your single leg jump! Simply having the correct biomechanics in a

    unilateral jump will help any athlete out immensely. In part II, I will break down the single leg jump into

    five primary components, and then discuss the exact actions that need to occur for an athlete to really

    get up off one leg. The five points are summarized as follows:

    1.

    Lowering the center of gravity in preparation to jump

    2.

    The rhythm of the last few steps

    3.

    A positive push of the penultimate leg

    4.

    A negative pull of the rigid takeoff leg

    5.A powerful drive knee of the swing leg

    Part II

    Five Elements of Single Leg Jumping

    We will now go into detail regarding each phase of the single leg jump. First, lets talk about the lowering

    of the COG in the single leg jump. The following diagram shows the path of an athlete and their center of

    mass as they prepare to takeoff in a single leg jump.

  • 5/21/2018 Mechanics and Development of Single Leg Vertical Jumping

    Notice that in the last 2-3 steps before the plant, the athlete will lower their center of gravity down a few

    inches which allows the takeoff leg to be set up in front of the body and create the lever system which

    will promptly send it skyward. It is important to realize that some athletes will lower their center of

    gravity more than others. Athletes who are stronger in the weight room and who tend to have a bit

    more power or cross sectional muscle area may lower themselves a bit more than thinner, speed-based

    athletes who cant manage a whole lot more than their bodyweight in a parallel squat. Even amongst

    elite high jump athletes there is a significant range in how much the center of mass is lowered at the

    takeoff.

    Lowering the center of mass is important, but in order to do it correctly, a certain rhythm must be

    acquired. Athletes that can jump very well off of one leg will have this takeoff rhythm built into their

    subconscious. Track coaches will often refer to the last two steps in a unilateral jump as a quick-quick

    or flat-flat rhythm (we will get into the whole flat-flat concept later). The rhythm of the last three

    steps has also been referred to as a Day To-Day (speed of annunciating the syllables) format. You

    could also look at it as: 1..2,3! The rhythm of the last step also involves the takeoff step being shorter

    than normal. The last step is typically shortened as a result of the athlete lowering their center of mass

    prior to takeoff.

    In addition to a fast last step, the rhythm/attitude of the last several steps in general need to be ones of

    aggressiveness and acceleration. In a single leg jump (or even a running double leg jump for that matter)

    one needs to run and accelerate into the plant. Slowing down on the last couple steps, especially the final

    step (the plant), will cause a pretty severe loss in total jump height because it breaks the rhythm of the

    takeoff.

    Perhaps the simplest cues for an athlete to consider in a single leg jump are to lower their hips just a

    bit over the course of their third to last and second to last strides, and then keep the last step quick.

    This is done all while accelerating into the takeoff; making the last step too long and slow is a recipe for

    disaster this being the cause of many missed dunks and failed high jump attempts. The rhythm of

    these steps should develop over time, and when it is learned, it will tend to become very aggressive in

    elite one leg jumpers, particularly track and field high jumpers.

  • 5/21/2018 Mechanics and Development of Single Leg Vertical Jumping

    On a final note, while it is important to have good acceleration into a one leg jump, when going for

    maximal height, it is possible to run toofast. If you go into a single leg jump for height all out with a big

    run up, you may find that your speed is just a little too much to control. What will tend to happen

    during a takeoff with too much speed is that the knee will buckle from excessive eccentric loading on

    the quadriceps muscle group. Performing a single leg jump from a 3 step approach is a nice drill to learnthe single leg jump, but it is a different skill than doing a single leg jump from a 10-15 step run-up at

    high speeds. Because of this, it is important to learn what your body can and cant handle in terms of

    final takeoff speed, and also to practice your jumping from different lengths of

    approaches (we will get to this later in the application section).

    Penultimate Leg Action

    Breaking the single leg jump down even further, we can take a look at the action of the penultimate leg

    in a single leg takeoff. The penultimateleg refers to the second to last step in a single leg jump. If you

    jump off your right leg, then your left leg on the second to last step will be your penultimate leg. The

    penultimate step will be initiated by the heel driving towards the ground, and the foot in a dorsi-flexedposition (toe pointing up), and land the foot directly under the body. Athletes should be taught to lower

    their body as a whole during this phase in both a forward and downward direction (forward especially

    when trying to conserve speed and achieve any horizontal distance in the jump). Although bringing the

    foot directly under the body is what the athlete should be thinking of when performing the penultimate

    step, the foot will actually touch down slightly in front of the body. Here is a picture of what the

    initiation of this second to last step looks like.

    Penultimate Step: Dorsiflex the Ankle

    As you can see from the picture, the athlete is pointing his toe upwards (dorsiflexion) and driving the

    heel down towards the ground to initiate the penultimate step. The penultimate leg does two main

    things to help prepare the body in a single leg jump.

  • 5/21/2018 Mechanics and Development of Single Leg Vertical Jumping

    1. Bend the knee joint a bit more than normal to help with the final lowering of the center of gravity

    (remember, the center of gravity needs to be lowered in order to go up). The picture below illustrates

    the lowering that occurs during the penultimate step. Notice how the penultimate leg is planted with a

    significant knee bend and slightly ahead of the center of mass. During this phase, you will notice how the

    athletes hips are lowered to a significantly greater degree than during normal upright running.

    Penultimate Step

    2. In addition to lowering the COG, the penultimate leg will also provide aforward push onto the plant

    leg. This forward push leads to a very active takeoff rather than a passive one. As was mentioned

    before, expert single leg jumpers are very proficient at keeping their acceleration up through their plant

    in the takeoff. The picture below helps serve as an illustration as to how this works.

    As you can see from the picture above, the penultimate leg is pushing forwards off the toe to maintain

    speed into the plant before the athlete jumps to clear the hurdle. Losing speed into the plant will also

    tend to put the body in a bad takeoff position and shift the loading of the plant leg more onto the knee

    and the quadriceps group rather than the hips. This will result in a buckling of the takeoff leg. Key Point:

  • 5/21/2018 Mechanics and Development of Single Leg Vertical Jumping

    The body is in the most powerful position when the takeoff leg is fairly straight and the majority of theforce involved in the jump is absorbed through the hips.

    Performing the penultimate step correctly is vital to getting a good knee drive when you get into the next

    phase of the jump. In many skill related activities, especially those in track and field, many coaches look

    at the particulars of a certain phase of movement, and dont understand that it is often the precedingmovement in the kinetic chain that leads athletes to that point. When the penultimate step is performed

    correctly, the penultimate leg will slightly lag behind the body of the athlete and load itself up in an

    elastic manner. Upon the plant of the jump, the leg can snap forward and deliver a powerful knee drive

    in addition to the planting action of the takeoff leg. This leads us to the next aspect of a single leg jump

    which is the action of the plant leg.

    Plant Leg

    The final phase in setting up the single leg jump is the action of the plant leg. If everything has gone

    correctly so far, the action of the lead leg should happen smoothly. There are two key points to consider

    when it comes to the action of the plant leg.

    Pulling the plant leg down in a quick sweeping action towards the ground rather than a pushfrom below.

    Minimizing the amount of knee bend to form the strongest lever possible (different athletes will

    have different amounts of optimal knee bend, and it is unwise/unsafe to plant on a locked out

    knee, but generally speaking, knee bend should be reduced as much as possible).

    When putting together all phases of the jump, the rhythm in the last two steps in the jump is something

    like push---pull-plant! What many athletes who have trouble jumping of one leg cannot seemto do is

    perform the pulling action of their plant leg; to them it is usually more of a push, or push-push-plant

    and then a poor and awkward looking vertical display! Illustrated below is a stick figure of an athlete

    performing a single leg jump with an incorrect plant leg.

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    Different athletes will have different amounts of bend and foot placement depending on their strength

    and anthropometrics (limb and tendon lengths). Light and fast athletes with short Achilles tendons will

    naturally have very little bend in their legs. Heavier and more powerful jumpers will run a bit slower

    and have a little more knee bend in their jump to allow themselves to use more of their power

    generated by their large muscles.

    Knee bend in the plant leg is also affected by the length of the Achilles tendon of the athlete. Those with

    longer Achilles tendons will tend to utilize greater knee bends in order to load up their tendon, while

    athletes with shorter Achilles will tend to have less of a knee bend and take advantage of the rebounding

    effect of a short and stiff tendon.

    The following video is part of a series comparing the jumping styles of high jumpers Donald Thomas and

    Stefan Holm. Thomas has long Achilles tendons, while Holms are very short. As a result, Thomas will

    naturally have a greater knee bend than Holm.

    http://www.youtube.com/watch?v=_iQbKfd1AfU

    The last two steps in a single leg jump (penultimate and final step) should both hit the ground flat. What

    this means is that the athlete should not be trying to jump off of their toe or the ball of the foot.

    Although sometimes a takeoff where the heels never hit the ground will happen with strong two leg

    jumpers, it will never be possible in a single leg jump due to significantly higher forces on the ankle joint

    and lower leg. Although people who tend to walk on the balls of their feet tend to be good single leg

    jumpers, this does not mean that the plant of the jumps also occurs entirely off the ball of the foot.

    Athletes who attempt to plant a single leg jump on their toe will find that their heel will be forced tothe ground very quickly (and thus bring about a massive loss in elastic energy)!

    The forces in a single leg jump are very high and the only way the leg can form a truly efficient lever

    system is with a flat foot driven plant. Planting on the toe will usually cause the lever to mush down

    under the force of the body and its momentum. In addition to the plant leg, the penultimate (second to

    last step) in a single leg jump is typically given the recommendation of coming down flat. This advice is

    given to help the athlete in remembering to lower their center of mass, but a great single leg jump can

    also be performed without the penultimate coming down flat. Quick-quick can be a better cue for the

    last couple of steps.

    Posture in the Plant

    When an athlete plants in a single leg jump, their body posture is crucial to the effectiveness of the

    takeoff. In order to accommodate the lever system and speed of the jump, the torso should be straight

    up and down or sometimes slightly backwards.A critical mistake that an athlete could make in a single

    leg jump would be to takeoff with the torso in a forward lean. In a track and field high jump, the torso is

    aligned behind the hips and this actually forms a straight backwards lever from head to toe as indicated

    by the picture below

    http://www.youtube.com/watch?v=_iQbKfd1AfUhttp://www.youtube.com/watch?v=_iQbKfd1AfU
  • 5/21/2018 Mechanics and Development of Single Leg Vertical Jumping

    Anna Chicherova demonstrates the backwards lever action that is present in a track and field high jump(and most other single leg jumps)

    For other running jumps, such as a running dunk on a fast break, the torso doesnt have to have a hugeamount of backwards lean, nor should it but there should never really be any forward lean of the torso.

    Tom Chambers exhibits a slight backwards torso lean in his famous dunk

    Knee Drive at Takeoff

    The final aspect of a good single leg jump is a powerful and effective knee drive. In a single leg jump,

    the action of the driving knee contributes greatly to the vertical velocity of the movement.Try this simple

    exercise to see just how high the contribution is:

  • 5/21/2018 Mechanics and Development of Single Leg Vertical Jumping

    Knee Drive Exercise: Perform a regular standing vertical jump off of one leg against the wall or under a

    basketball hoop and see how high you could touch. Dont think about anything except for how high you

    can touch. Now try the same thing and dont allow your non-jumping knee to drive up; make it stays

    down by your jumping leg. How high did you jump compared to your first jump? Perhaps half as h igh if

    you did well!

    When an athlete plants on a single leg to take off, the swing leg comes through quickly and blocks

    when it reaches a position around parallel or higher, at least this is the optimal situation; many athletes

    drive knees do not reach parallel when they are jumping, and coincidentally, these athletes tend not to

    have very good jumps off of one leg. The drive knee needs to only come up much farther than parallel,

    however. If it drives up to the chest, for example, this is actually too much, and will cause the jump

    height to be less overall.

    The reason why is driving too far would decrease jump height is because, when the knee stops, (also called a

    block by track coaches) it adds its momentum to the jump. If the knee never stops, or doesnt stop on time

    in the kinetic chain, it can never add its momentum to the jump. Often times, many coaches will actuallysuggest an athlete driving their knee hard, and then not realize that the athlete is actually blocking too late,

    or not really blocking. and taking away from their total jump height.

    To get the picture of the effect of a block in terms of momentum transfer, try this drill. Sit on the

    ground with your legs out in front of you and your back straight. Swing your arms upwards with the goal

    of trying to lift your body off the ground a few inches. You will have to swing as hard as your can for

    this to happen. Notice where your arms stop in this movement, it should be when your upper arms are

    about parallel to the ground. Now try the drill by just letting your arms swing all the way in the air

    without stopping them. How high did you get? When athletes keep driving their lead knee too far past

    parallel without attention to the blocking action (as they are sometimes improperly advised to by track

    coaches) they will actually take away from their jump. It is important for athletes to make sure they arestopping their drive knee at slightly past parallel to maximize their single leg jump!

    Part of the reason that it is important to have a good drive knee in a single leg jump is to attain a highercenter of mass at the point of takeoff. As far as physics goes, total jump height is a product of:

    1.Vertical velocity at toe-off

    2.

    Vertical position at toe-off

    Vertical velocity at toe-off is simple, it is the speed that your body is traveling when your toe leaves the

    ground in a jump. More powerful athletes with better technique will have greater vertical velocity at toe-off than their lower level counterparts. The vertical position at toe off is that of the center of gravity.

    Having a better knee drive will raise the center of gravity in the athlete by a couple of inches. In addition

    to getting the drive knee up off the ground, it is also important to shrug the shoulders upwards and bring

    the arms above the level of the head at the point of takeoff. When an athlete does this, they will raise

    their center of mass a couple of inches higher than it normally sits.

    Typically, the center of your bodies mass rests just below the belly button, but it can be raised through

  • 5/21/2018 Mechanics and Development of Single Leg Vertical Jumping

    the effective use of the arms, shoulder and drive knee mentioned above. Although the concept of raising

    ones center of mass at takeoff helping vertical jump may seem a little hard to understand, the picture

    below will attempt to make things more clear.

    In addition to the above picture, here is a side by side comparison of three jumpers at toe-off, the one on

    the left having the highest one leg jump, and the one on the right having the lowest overall jump. Notice

    the difference in limb positioning at the point of takeoff, and the jumper whose limbs are highest vs.

    those whose limbs are the lowest.

    With this in mind, lets put all this information together. These points allow us to see a picture sequence

    of what all goes into a good single leg jump. The following picture sequences highlight the differences

    between skilled single leg takeoffs and unskilled ones. Take a video and check out your own jump,

    which one looks more like you?

  • 5/21/2018 Mechanics and Development of Single Leg Vertical Jumping

    Tyler (400m runner in track and field): Low skill in single leg jump (30+ Standing VJ however)

    Jake (Javelin Thrower): Moderate skill in single leg jumping

    Joel (High Jumper) High skill in single leg jumping

  • 5/21/2018 Mechanics and Development of Single Leg Vertical Jumping

    If your current single leg jumping looks like the first series of slides, you have your work cut out for you,but you can definitely still improve your leap off of a single leg! This concludes part II of this article on

    the single leg jump. By reading this first section, you will have a good idea of why you may or may not

    currently excel at single leg jumping.

    If you are not good at getting up off one leg, it is nice to know the theory of how things should look, but

    you also need to know the best path to take to get better! The second part of this article will be

    dedicated to how muscle stiffness plays a role in a single leg jump, and then drills and exercises that can

    be done to improve both biomechanics and leg stiffness. No matter what your current single leg ability

    is, you can get better!

    All the information above was fairly long winded and perhaps a bit difficult to all take in at once, so hereis a summary of what we went over:

    Athletes must lower their center of mass when jumping in order to achieve any sort of vertical

    liftoff. In a single leg jump this lowering typically happens over the course of the final three

    steps.

    Any running jump, whether off of one leg or two is based on using the legs as levers to convert

    the athletes horizontal velocity into vertical velocity, similar to how a pole vaulter uses a pole

    to lift their body several meters into the air. A one leg uses this lever system to a greater extent

    than a running two foot jump.

    Athletes of differing builds will have their own optimal way of jumping, so one cannot put allathletes into one box regarding how to properly configure ones limbs in a single leg jump.

    Some athletes are also simply built to perform running jumps better than others, and

    regarding single leg jumps, the length of the Achilles tendon is a critical factor in how the jump

    is performed.

  • 5/21/2018 Mechanics and Development of Single Leg Vertical Jumping

    The second to last step in a single leg takeoff is the penultimate step. It should have a little

    greater knee bend (to help keep the COG low) and be devoted to providing a solid forward

    push onto the plant leg.

    The last step, or plant step, in a single leg jump should pull downwards and land fairly straight.

    The plant should be driven off the flat of the foot. Athletes who cannot manage to pull their plantleg downwards but instead push it, will tend to focus too much energy on their knee joint, lose

    the rigid takeoff lever, and thus, not jump very high.

    The driving knee in a single leg jump massively contributes to the total upward lift in a single leg

    takeoff. It should stop or block when it reaches a position of parallel to the ground. If it does

    not reach parallel, or goes past it when it stops, energy will be lost in the jump.

    Part III - Physical Qualities of a One Leg Jumper

    In Part I and II of this series, the biomechanical qualities that allow an athlete to get up off one leg were

    discussed in detail. Section III is designed to teach the physical quality of jumping that backs the

    biomechanical action of the takeoff leg, which is muscle-tendon stiffness. In the end of the article, part IV

    will show some of the best plyometrics, drills, and lifts available that can be used to increase ones single

    leg jumping ability.

    A good single leg jumper needs to excel at having high muscle-tendon stiffness in relation to theirbodyweight, particularly in the hips, knee, and ankle joints. Creating high amounts of stiffness in the

    takeoff leg is created through more than just strength found in the weightroom. Within a single leg

    takeoff, the leg must absorb up to 10x the athletes bodyweight or more. The ability of the takeoff leg to

    absorb up these great forces is based on ability of the muscle and tendons to act together to produce an

    extremely brief, but very high amount of tension and stiffness. Check out the following video to see

    some massive impact forces that are present in a single leg jump.

    http://www.youtube.com/watch?v=b4ivgEW5GRo&feature=related

    The muscle action that is present in this particular movement is actually that of an explosive isometric

    type, rather than a standard eccentric-isometric-concentric motion seen in weightlifting. What reallyhappens in a single leg jump is that the muscles will contract hard isometrically; i.e. they lock up. When

    the muscles lock up, the tendons will go through the stretch shortening cycle of lengthening and

    contracting, while the muscles keep a similar length. Considering the extreme forces present in vertical

    jumps, this is the only way that the muscles can sustain the forces of the jump.

    Concentric motion of muscle is the weakest of the three phases, while the eccentric/isometric phases aremuch stronger and can handle these high forces for a brief instant. This whole motion is very much

    http://www.youtube.com/watch?v=b4ivgEW5GRo&feature=relatedhttp://www.youtube.com/watch?v=b4ivgEW5GRo&feature=related
  • 5/21/2018 Mechanics and Development of Single Leg Vertical Jumping

    different than weightlifting, so one cannot rely heavily on weightlifting to directly enhance these typesof dynamic movements (although weightlifting can certainly help in long term development).

    The joint which requires the greatest amount of stiffness in the single leg jump is the ankle joint.

    Research has shown that the less knee flexion and ground contact time that is present in a jump, the

    higher the impact forces that exist on the ankle joint. When you consider that worldheight over headjumped record holder Stefan Holm has Achilles tendons that are 4x stiffer than the average human

    being, you will realize that this is no mistake!

    Single leg jumpers have been said to be forefoot dominantathletes. They tend to walk more on their

    toes and have a little bit of bounce to their step. This is not because those athletes plant on their toe

    when they jump (because they dont) but more so because constantly pressuring their Achilles tendon

    and improving its level of stiffness. By actively engaging the forefoot in dynamic activity, these athletes

    also wills well as increase the amount of power they transmit through their glutes and hips. As such, it

    can be helpful to do a large amount of barefoot style training to learn to activate the forefoot more if you

    are lacking in that area.

    Vibram Five-Fingers: A great way to train barefoot and build power off your forefoot

    Just performing squats and deadlifts cannot fully develop these high levels of muscular stiffness. If you

    disagree, just take a minute to look at the builds of world class high jumpers. These athletes are

    tremendously thin and dont look like they belong anywhere near a powerlifting meet (although in reality,

    many of them actually have pretty good squats in relation to their bodyweight, although they are never

    going to win a lifting competition. It is also important to know, that even though those athletes can

    usually squat a good deal of weight, squatting heavy isnt what got most of them to that point, they are

    just tremendously explosive athletes, and even doing things like hill running and plyometrics will drive up

    their squat) In order to become a truly effective single leg jumper, elastic training needs to make up a

    large part of your workouts.

  • 5/21/2018 Mechanics and Development of Single Leg Vertical Jumping

    Two powerful athletes: Total body speed/stiffness vs. heavy muscle power

    Bodyweight Factors in Single Leg Jumping

    When considering the stiffness of the takeoff leg in a single leg jump, it is important to take bodyweight into

    account. Although there are exceptions here and there, a general rule of thumb in one vs. two leg jumping is

    that lighter athletes will tend to be better single leg jumpers, while heavier and more muscular athletes will be

    more suited towards the two legged jump. Here are some sample builds of recent world champion high

    jumpers: 60, 155lbs, 66, 190lbs, 511, 150lbs, 64, 180lbs. The faster the jump, the more the frame of thebody and muscle-tendon action is relied upon. If you are really looking to build up your single leg jump, and

    you may have some extra pounds, you need to seriously consider losing some weight to really get up there off

    of one leg. This applies mainly to track and field competitors who dont have to worry about jumping off of two

    legs, but if your bodyfat % is a bit high, you will certainly want to lose some weight, nobody wants to jump in

    a 10lb vest of bodyfat. In some cases, this will also mean watching how much upper -body work you are

    doing, if you want to really excel in single leg jumping. Not all athletes are prone to a lot of upper body mass

    development, but it can cause issues for some.

  • 5/21/2018 Mechanics and Development of Single Leg Vertical Jumping

    Olympic high jumpers: Not always a factory of muscle.

    The weight of an athlete will influence the run-up speed of the jump. Heavier athletes who are adept at

    jumping off of one leg will tend to do a little better with a slower run-up, while lighter athletes will

    typically do better with faster run-ups (optimal run up speed depends on the length of their Achilles

    tendons as well). Lighter athletes tend to do better at speed oriented, single leg jumping for the

    following reason: High force/high speed takeoffs rely on the strength that the body can develop in .2

    tenths of asecond or less in relation to that athletes bodyweight. When a light athlete plants for a one

    leg jump witha very straight/rigid takeoff leg, that straight lever can handle a very large amount of

    force! In the case of a single leg jump, large amounts of muscle mass are not nearly as important as anefficient and powerful amount of muscle mass performing an explosive-isometric contraction and

    producing massive amounts of muscle tendon stiffness in a very short period of time.

    The practice pyramid

    The primary forms of training that will aid the physical properties of single leg jumping are those of direct

    practice, speed, and plyometric based work. Direct practice is usually the most important area to focus on

    and refers to actually jumping off of one leg for maximal height or doing drills that can break down the

    pieces of the single leg jump and make it more efficient. Speed work refers to sprints on flat surfaces or

    hills. Run-up speed can be important in running jumps, as well as the ability to accelerate quickly into the

    takeoff. When it comes to training the high jump in track and field, speed is an essential quality thatneeds to be improved throughout the year. There are certain speed standards that are typically assumed

    for certain levels of performance in a single leg high jump. Finally, plyometrics are a vital ingredient in

    developing a powerful one leg jump. Plyometrics provide a direct way to train the specific explosive

    isometric muscle contraction that is relied on so heavily in a fast single leg jump.

    Starting early, practice makes perfect.

  • 5/21/2018 Mechanics and Development of Single Leg Vertical Jumping

    Lets talk about how direct practice and motor learning are of great importance when considering the

    one legged jump. Perhaps the most important reason efficient single leg jumpers are good at that skill is

    because they learned to jump that way from when they were young. Science has proven that it takes

    around 10,000 repetitions of a particular motor skill before mastery of it can be achieved. Athletes who

    started practicing jumping off of one leg early in their lives will have a huge advantage over those

    athletes who have not! Also, even those athletes who are pretty good at jumping off of one leg willusually be fairly mediocre at jumping off their off leg, because they have not practiced the motor

    coordination of jumping off of the other side of their body!

    For comparisons sake, imagine hardly ever practicing, or not learning how to sprint until you were

    perhaps 15,16 or 17 years old? How far behind your peers do you think you would be in this case? Would

    you ever be able to really catch up? You would be able to catch up a little certainly, but since neural

    pathways are really developed at a young age, it is important to get that ball rolling in an athletes early

    years. In my own experience, I learned how to jump off of one foot around age 10 when a classmate

    suggested I might be able to jump higher that way. I tried it and found it to be quite effective, I could

    just an inch or so higher using that method at the time (yes, I have a good memory). Ever since that

    point I was hooked and was constantly trying to jump as high as I could at my school to touchlights/beams etc. When I had reached age 14 I could dunk miniature and deflated basketballs off of one

    leg, but yet I could barely touch the rim jumping off of two feet. My practice of the one leg technique had

    allowed me to achieve a good level of mastery in that area after several years of practice.

    A young Stefan Holm gains an early start on his jumping career

    Plyometrics complimented by strength training provide the backbone of a good single leg jumping

    development program. There are a multitude of plyometric exercises that are available to athletes to

    help them increase their single leg leaping ability. Great basic exercises to help develop the elastic quality

    of the muscle tendon complex would involve submaximal plyometric exercises such as tuck jumps, squat

  • 5/21/2018 Mechanics and Development of Single Leg Vertical Jumping

    jumps, line hops, skater hops, pike jumps, and any other low intensity hopping exercise where the

    ground contact time is fairly low. Athletes should aim to become proficient at these exercises prior to

    moving on to more advanced exercises such as bounding, depth jumps, and hurdle hops, especially

    younger athletes or those without much prior training. Once an athlete does reach a high level,

    improving ones skill at more advanced plyometrics will really help to increase the stiffness of the ankle,

    knee and hip joints and will start to cause single leg jumps to feel fairly effortless.

    On top of plyometrics, one of the final keys to becoming truly proficient at single leg jumping is becoming

    more of a forefoot dominant athlete and having massive amount of stiffness in the lower leg and ankles.

    You can typically tell a forefoot dominant athlete as one who seems to bounce along as they walk or run.

    Their heels barely touch the ground! Because they have built up this particular habit of walking, they

    have amassed a high amount of stiffness, and their Achilles tendons are going to take more force to

    compress than someone who is much more heel dominant. Many track coaches will assign barefooted

    warm-ups for the reason of building forefoot power (that and injury prevention). My personal favorite

    modality for this particular aspect of fitness is that of barefoot rudiment hops. In this particular drill, the

    athlete will perform low amplitude hops with a stiff plant leg. This drill is an excellent way to develop

    power through the forefoot, and will be explained further in video in part IV.

    Part IV: Building a Single Leg Jumper

    The first two parts of this series were devoted to learning about the basic theory and technique ofimproving single leg jumping ability. This final article of the series gets down to business in regards to the

    actual exercises that will help you to tie everything together and hopefully put quite a few inches on your

    single leg running jump! Video sections covered in this final article will include: Plyometrics, Direct

    Practice Methods, Drills, and Supporting Strength Methods.

    The following is a list of exercises to help improve single leg vertical leaping. For the sake of this article, it

    will be assumed that the reader is familiar with simple plyometrics such as tuck jump, squat jumps, line

    hops etc.

    Direct Practice (Direct Jumping Coordination):

    Practicing single leg jumps for height from 3,5, and 10 step approaches1-2-3 Jump

    http://www.youtube.com/watch?v=veK0y0HRlj4&feature=channel_video_titl e

    1-2-3Jump over short hurdles

    http://www.youtube.com/watch?v=ZkUC_Y-

    x3ow&list=UUeVON2SD5dFiqAavFcyC5rw&index=7&feature=plpp_vide o

    http://www.youtube.com/watch?v=veK0y0HRlj4&feature=channel_video_titlehttp://www.youtube.com/watch?v=ZkUC_Y-x3ow&list=UUeVON2SD5dFiqAavFcyC5rw&index=7&feature=plpp_videohttp://www.youtube.com/watch?v=ZkUC_Y-x3ow&list=UUeVON2SD5dFiqAavFcyC5rw&index=7&feature=plpp_videohttp://www.youtube.com/watch?v=ZkUC_Y-x3ow&list=UUeVON2SD5dFiqAavFcyC5rw&index=7&feature=plpp_videohttp://www.youtube.com/watch?v=ZkUC_Y-x3ow&list=UUeVON2SD5dFiqAavFcyC5rw&index=7&feature=plpp_videohttp://www.youtube.com/watch?v=ZkUC_Y-x3ow&list=UUeVON2SD5dFiqAavFcyC5rw&index=7&feature=plpp_videohttp://www.youtube.com/watch?v=ZkUC_Y-x3ow&list=UUeVON2SD5dFiqAavFcyC5rw&index=7&feature=plpp_videohttp://www.youtube.com/watch?v=ZkUC_Y-x3ow&list=UUeVON2SD5dFiqAavFcyC5rw&index=7&feature=plpp_videohttp://www.youtube.com/watch?v=veK0y0HRlj4&feature=channel_video_title
  • 5/21/2018 Mechanics and Development of Single Leg Vertical Jumping

    Holm Hurdles

    http://www.youtube.com/watch?v=WVZ3ZcorTF0

    Assistive Drills (Jumping Coordination Assistance):

    Skips for Height

    http://www.youtube.com/watch?v=qx7qj-Jj1lY

    Repeating Takeoff

    http://www.youtube.com/watch?v=lhqJcDzOJWM&feature=relate d

    Repeating Takeoff Emphasizing COG Heighthttps://www.youtube.com/watch?v=qxdf8UbgpTc&feature=channel_video_titl e

    Center of Gravity Bench Takeoffs

    http://www.youtube.com/watch?v=gtx11MzBP5Q&feature=relate d

    Two Step Knee Drives

    http://www.youtube.com/watch?v=56MXNjgoZX8&list=UUeVON2SD5dFiqAavFcyC5rw&index=1&featur e

    =plcp

    Basic PlyometricsTuck Jumps

    Squat Jumps

    Lunge Jumps

    Butt Kicker Jumps

    Stair Runs

    Low Box to Box JumpsBench Jumps

    Cone HopsLine Hops

    Rudiment Hops

    http://www.youtube.com/watch?v=lvkQgU7Nr38

    Advanced Plyometrics (Stuctural and Motor Recruitment):

    Bounding

    http://www.youtube.com/watch?v=0bQuLV1MFSQ

    Scissor Bounding

    http://www.youtube.com/watch?v=eci4lO2FhSk&feature=relate d

    Hurdle Hops

    http://www.youtube.com/watch?v=LqsmO4POv7c

    Single Leg Hurdle Hopshttp://www.youtube.com/watch?v=re0M7vc3yuU

    http://www.youtube.com/watch?v=WVZ3ZcorTF0http://www.youtube.com/watch?v=qx7qj-Jj1lYhttp://www.youtube.com/watch?v=lhqJcDzOJWM&feature=relatedhttps://www.youtube.com/watch?v=qxdf8UbgpTc&feature=channel_video_titlehttps://www.youtube.com/watch?v=qxdf8UbgpTc&feature=channel_video_titlehttp://www.youtube.com/watch?v=gtx11MzBP5Q&feature=relatedhttp://www.youtube.com/watch?v=56MXNjgoZX8&list=UUeVON2SD5dFiqAavFcyC5rw&index=1&feature=plcphttp://www.youtube.com/watch?v=56MXNjgoZX8&list=UUeVON2SD5dFiqAavFcyC5rw&index=1&feature=plcphttp://www.youtube.com/watch?v=56MXNjgoZX8&list=UUeVON2SD5dFiqAavFcyC5rw&index=1&feature=plcphttp://www.youtube.com/watch?v=56MXNjgoZX8&list=UUeVON2SD5dFiqAavFcyC5rw&index=1&feature=plcphttp://www.youtube.com/watch?v=lvkQgU7Nr38http://www.youtube.com/watch?v=0bQuLV1MFSQhttp://www.youtube.com/watch?v=eci4lO2FhSk&feature=relatedhttp://www.youtube.com/watch?v=LqsmO4POv7chttp://www.youtube.com/watch?v=re0M7vc3yuUhttp://www.youtube.com/watch?v=re0M7vc3yuUhttp://www.youtube.com/watch?v=LqsmO4POv7chttp://www.youtube.com/watch?v=eci4lO2FhSk&feature=relatedhttp://www.youtube.com/watch?v=0bQuLV1MFSQhttp://www.youtube.com/watch?v=lvkQgU7Nr38http://www.youtube.com/watch?v=56MXNjgoZX8&list=UUeVON2SD5dFiqAavFcyC5rw&index=1&feature=plcphttp://www.youtube.com/watch?v=56MXNjgoZX8&list=UUeVON2SD5dFiqAavFcyC5rw&index=1&feature=plcphttp://www.youtube.com/watch?v=56MXNjgoZX8&list=UUeVON2SD5dFiqAavFcyC5rw&index=1&feature=plcphttp://www.youtube.com/watch?v=56MXNjgoZX8&list=UUeVON2SD5dFiqAavFcyC5rw&index=1&feature=plcphttp://www.youtube.com/watch?v=gtx11MzBP5Q&feature=relatedhttps://www.youtube.com/watch?v=qxdf8UbgpTc&feature=channel_video_titlehttps://www.youtube.com/watch?v=qxdf8UbgpTc&feature=channel_video_titlehttp://www.youtube.com/watch?v=lhqJcDzOJWM&feature=relatedhttp://www.youtube.com/watch?v=qx7qj-Jj1lYhttp://www.youtube.com/watch?v=WVZ3ZcorTF0
  • 5/21/2018 Mechanics and Development of Single Leg Vertical Jumping

    Depth Jump

    http://www.youtube.com/watch?v=t1rfTfJ7iDg&feature=plcp&context=C34666c4UDOEgsToPDskLB1mQ z

    tuu3BEKyAMmV-C5B

    Single Leg Depth Jump

    http://www.youtube.com/watch?v=Oo9b4rnzz_I&feature=plcp&context=C38269d9UDOEgsToPDskL0iKwUxuWV0uGiz8bkryNj

    Helpful Strength Training Drills (Maximize Motor Pool and Injury Prevention):

    Pistol Squat

    http://www.youtube.com/watch?v=Ji00tONBmZE

    Explosive Pistol Squat

    http://www.youtube.com/watch?v=pvUSq9E2STk&list=UUE_HRDp99q7dJ5tWy26HYpg&index=1&featur e

    =plcp

    Barbell Skiphttps://www.youtube.com/watch?v=KQP91DSuATs

    Barbell Step-Uphttps://www.youtube.com/watch?v=SPFxUsCy7So

    Barefoot Running/Walking

    Now this information is all nice, but how can it help you as an athlete? How much can you improve? Well,

    that really depends on how hard you are willing to work at it and how much time you are willing to

    invest.

    If you like the exercises but are not sure exactly how to tie everything together in an organized program,

    feel free to send me an email. Right now I am perfectly willing to help you out for free as I have the

    time. You can also check out the free single leg jumping program I have put together which has brought

    about some great single leg jumping gains even in experienced athletes.

    http://www.just-fly-sports.com/?p=120

    Training really doesnt have to be all that complicated, in fact, it is really quite simple. Perhaps the

    simplest way to improve your vertical leap off one leg is to practice 10-20 jumps per day, 5-6 days a

    week off of one leg from different run ups (with technical considerations in mind), and then pick a few

    assistance exercises that you enjoy doing or you feel suit your needs. You will pick up the majority of

    your results from this simple method. Barefoot/forefoot training never hurts either!

    I am also working on an exciting new vertical jump development book, Vertical Ignition, coming out in2012. I look forward to hearing from your response to this report!

    Joel Smith, MS, CSCS

    http://www.youtube.com/watch?v=t1rfTfJ7iDg&feature=plcp&context=C34666c4UDOEgsToPDskLB1mQztuu3BEKyAMmV-C5Bhttp://www.youtube.com/watch?v=t1rfTfJ7iDg&feature=plcp&context=C34666c4UDOEgsToPDskLB1mQztuu3BEKyAMmV-C5Bhttp://www.youtube.com/watch?v=t1rfTfJ7iDg&feature=plcp&context=C34666c4UDOEgsToPDskLB1mQztuu3BEKyAMmV-C5Bhttp://www.youtube.com/watch?v=t1rfTfJ7iDg&feature=plcp&context=C34666c4UDOEgsToPDskLB1mQztuu3BEKyAMmV-C5Bhttp://www.youtube.com/watch?v=Oo9b4rnzz_I&feature=plcp&context=C38269d9UDOEgsToPDskL0iKwUxuWV0uGiz8bkryNjhttp://www.youtube.com/watch?v=Oo9b4rnzz_I&feature=plcp&context=C38269d9UDOEgsToPDskL0iKwUxuWV0uGiz8bkryNjhttp://www.youtube.com/watch?v=Oo9b4rnzz_I&feature=plcp&context=C38269d9UDOEgsToPDskL0iKwUxuWV0uGiz8bkryNjhttp://www.youtube.com/watch?v=Oo9b4rnzz_I&feature=plcp&context=C38269d9UDOEgsToPDskL0iKwUxuWV0uGiz8bkryNjhttp://www.youtube.com/watch?v=Ji00tONBmZEhttp://www.youtube.com/watch?v=pvUSq9E2STk&list=UUE_HRDp99q7dJ5tWy26HYpg&index=1&feature=plcphttp://www.youtube.com/watch?v=pvUSq9E2STk&list=UUE_HRDp99q7dJ5tWy26HYpg&index=1&feature=plcphttp://www.youtube.com/watch?v=pvUSq9E2STk&list=UUE_HRDp99q7dJ5tWy26HYpg&index=1&feature=plcphttp://www.youtube.com/watch?v=pvUSq9E2STk&list=UUE_HRDp99q7dJ5tWy26HYpg&index=1&feature=plcphttps://www.youtube.com/watch?v=KQP91DSuATshttps://www.youtube.com/watch?v=KQP91DSuATshttps://www.youtube.com/watch?v=SPFxUsCy7Sohttps://www.youtube.com/watch?v=SPFxUsCy7Sohttp://www.just-fly-sports.com/?p=120http://www.just-fly-sports.com/?p=120https://www.youtube.com/watch?v=SPFxUsCy7Sohttps://www.youtube.com/watch?v=SPFxUsCy7Sohttps://www.youtube.com/watch?v=KQP91DSuATshttps://www.youtube.com/watch?v=KQP91DSuATshttp://www.youtube.com/watch?v=pvUSq9E2STk&list=UUE_HRDp99q7dJ5tWy26HYpg&index=1&feature=plcphttp://www.youtube.com/watch?v=pvUSq9E2STk&list=UUE_HRDp99q7dJ5tWy26HYpg&index=1&feature=plcphttp://www.youtube.com/watch?v=pvUSq9E2STk&list=UUE_HRDp99q7dJ5tWy26HYpg&index=1&feature=plcphttp://www.youtube.com/watch?v=pvUSq9E2STk&list=UUE_HRDp99q7dJ5tWy26HYpg&index=1&feature=plcphttp://www.youtube.com/watch?v=Ji00tONBmZEhttp://www.youtube.com/watch?v=Oo9b4rnzz_I&feature=plcp&context=C38269d9UDOEgsToPDskL0iKwUxuWV0uGiz8bkryNjhttp://www.youtube.com/watch?v=Oo9b4rnzz_I&feature=plcp&context=C38269d9UDOEgsToPDskL0iKwUxuWV0uGiz8bkryNjhttp://www.youtube.com/watch?v=Oo9b4rnzz_I&feature=plcp&context=C38269d9UDOEgsToPDskL0iKwUxuWV0uGiz8bkryNjhttp://www.youtube.com/watch?v=Oo9b4rnzz_I&feature=plcp&context=C38269d9UDOEgsToPDskL0iKwUxuWV0uGiz8bkryNjhttp://www.youtube.com/watch?v=t1rfTfJ7iDg&feature=plcp&context=C34666c4UDOEgsToPDskLB1mQztuu3BEKyAMmV-C5Bhttp://www.youtube.com/watch?v=t1rfTfJ7iDg&feature=plcp&context=C34666c4UDOEgsToPDskLB1mQztuu3BEKyAMmV-C5Bhttp://www.youtube.com/watch?v=t1rfTfJ7iDg&feature=plcp&context=C34666c4UDOEgsToPDskLB1mQztuu3BEKyAMmV-C5Bhttp://www.youtube.com/watch?v=t1rfTfJ7iDg&feature=plcp&context=C34666c4UDOEgsToPDskLB1mQztuu3BEKyAMmV-C5B
  • 5/21/2018 Mechanics and Development of Single Leg Vertical Jumping

    References:

    25 Tips for Coaching the Horizontal Jumps. Mike Pullins, Championship Productions, 2007.

    Baggett, Kelly. "Unscrambling the Puzzle of The 1-leg Jump." Jump Higher, Run Faster, and Perform

    Better - Enhance Athletic Ability. Web. 19 Dec. 2011.< http://www.higher-faster-sports.com/unilateraljump.html>.

    Best of British Track and Field, Coaching the High Jump. Alex Fuzz Caan. Championship Productions.

    2009.

    Earp, J. E., R. U. Newton, P. Cormie, and Kraemer J. W. "The Influence of Muscle-Tendon Unit Structure

    on Rate of Force Development, During the Squat, Countermovement, and Depth Drop Jumps." Journal of

    Strength and Conditioning Research 25 (2011). Web.

    Jacoby, Ed, and Bob Fraley. Complete Book of Jumps. Champaign, IL: Human Kinetics, 1995. Print.

    Nelsen, Roger Jr., Engineering an Athlete.PDF Version.

    Rogers, Joseph L. USA Track & Field Coaching Manual. Champaign, IL: Human Kinetics, 2000. Print.