Single Leg Jump Differences: The Anatomy of a Freethrow Line Dunk

Generally speaking, I get two staple questions regarding vertical jumping and associated training:

My training has looked like this ________, what do I do to jump higher?

How do I jump up/out better off of one foot? (usually out)

Many athletes can jump up off of one leg well. Fewer can jump up and out with as much skill and power. Jumping high off one leg is nice, but the majority of highlight reels feature an athlete grabbing a steal, running the court, taking off from just a step inside the free throw line, and punching down a monster slam. This elusive ability is what so many athletes are looking for.

If you are looking for a nice definition of jumping up AND out effectively, check out this video below. We’ll chat about a few of the mechanics in the video in a few paragraphs

Being around track and field for a few years, as well as working with a variety of jumpers in an extended weight-room setting has helped me to gain an idea of not only the biomechanics that separates these qualities, but also some of the specific strength associated with the various movement patterns of long jump vs. high jump specialists.

Let’s get into what it takes to get up off one leg, in both the vertical and horizontal vectors, starting with vertical.

We all know and love this dunk contest display. This is the epitome of an athlete who excels at jumping up off one leg

What does it take to jump up off one leg?

Good feet
Good control and timing of glutes
Speed and acceleration
Quad strength
Coordination

Looking at jumping off of one leg from the perspective of a track and field high jumper, one can see that a variety of body styles and strengths can create vertical lift off of the ground off of one leg.

Using the track and field high jump to assess some qualities of jumping up, a variety of builds and ground contact times can yield success in jumping up off one leg. Clearly the athletes with quicker ground contacts in takeoff are more prone to being able to also take that force out, but a quick ground contact isn’t a guarantee that one can also jump very high off of one leg. If this were true, every long jumper would likely be doubling in high jump. (In this case, the deficiencies are usually foot function and coordination.)

Outside of track and field philosophy, it takes a few select qualities that athletes should be adept at to leap off one leg.

The first is that the foot and ankle complex is strong, resistant to deformity, and can absorb and release energy well. Athletes who leak power through the feet and ankles are at a severe disadvantage. Imagine taking the spring out of a pogo stick for a bit of an over-exaggerated example of how an athlete with dysfunctional feet will function in a one leg jump. Remember, a single leg effort is simply transferring force through a rigid lever (the leg), to take an athlete’s horizontal speed to vertical.

These athletes also must have good function of the glutes and controllers of the hip. This doesn’t necessarily mean absolute strength, as the glutes of high jumpers are rarely even close to the development of 100m sprinters. Rather, it means that when the foot plants to takeoff (or perhaps, even a few milliseconds prior), the glutes and lateral sling (adductor/glute medius/quadratus lumborum) mechanisms are beginning to contract to provide the leg instant control and rigidity when the foot hits, and force transfer begins.

If the glute and sling mechanism are “late” in contracting, they transfer the force to other, compensating muscles, and much of the force transfer of the jump will be lost. This situation also makes it harder for the athlete to plant the foot ahead of the center of mass effectively (needed to create the rigid lever to transfer force upwards), as the muscular control won’t be there in that plant position, so the brain shuts the movement down. You’ll often see athletes who tend to jump with a lack of a rigid takeoff leg, positive shin angles, and poor knee drives as those who have a lack of control and timing in these muscle groups.

Quad and knee extensor strength is important for controlling the deceleration of the shin, as well as stabilizing the knee, and maintaining the leg as a rigid lever in the takeoff. A lot of press is given to the posterior chain in single-leg jumping, as it should be, but one should never forget that jumper’s knee is called that for a reason, and that is because jumping is not possible without lots of tension running through the patellar tendon. A powerful knee extension helps jumpers off one or two legs!

To jump up well off one leg takes one of either two things: low bodyweight and spectacular force transfer through the feet, or very strong knee extensors and glutes. Many times, this is a combination of some form of both qualities. I’ll list three general “types” of single-leg jumpers/high jumpers here for you.

Pure Speed Jumper (Example: Mutaz Barshim, Zach LaVine, James White)

This athlete is typically very low body weight, with great foot strength, and power off of the big toe. They tend to be pretty lousy at squatting anything below 90 degrees of knee bend with much strength or power. Their takeoff is characterized by a tight “folding” of the swing leg foot into the buttocks during the planting mechanism, that goes along with their quick contact in takeoff. There is a specific strength that goes along with this folding, and it cannot be just corrected by cueing (a common mistake of many coaches). The more speed this athlete can bring into their jump, the better.

Pure Power Jumper (Example: Shannon Brown)

This athlete is usually pretty strong and coordinated. They do well at squatting deeper if their limbs can handle it. They also usually boast decent Olympic lifting numbers, and they generally (but not always) enjoy the weight room. If they enjoy it too much, they’ll end up taking the tension in the face and body found in the weight room into their movements on the track, field, or court, which seriously hampers their speed and ability to stay healthy.

Hybrid Jumper (Example: Lebron James, Vince Carter)

This athlete shares characteristics of both types of one leg jumpers. There is quite a spectrum here in regards to what is achievable.

**What does it take to jump up and out off one leg?**

Speed and associated biomechanical strengths
Good feet
Good control and timing of glutes
Coordination
Quad strength

Put all this together, and you get something like this:

James White’s speed and mechanics allow him to not only jump up freakishly high, but do what nobody else in the world can do, and take that vertical out

So we know the basics of jumping up off one leg, but what extra qualities might it take to jump outward well. I’ll say this right away, the ability to jump up and out powerfully is the mark of an explosive, healthy athlete! This type of athlete has it all, strength, speed, explosiveness and coordination. I’ve seen relatively “unathletic” individuals with an ability to jump upwards well off one leg, but only the best of the best can jump out and up with speed and power. There is a reason that dunking a basketball from the free-throw line is such a special feat, even more impressive than a 8 meter long jump in track and field.

To jump high and far, an athlete needs speed. God-given, fast twitch fibers are a useful and important part of this, but it isn’t everything. For a long time, and still today, most coaches believe that early acceleration is highly trainable (it is), but top-end speed is pretty limited in its improvability. While this has some truth, putting a limiter here creates a self-fulfilling prophecy for too many athletes who deserve better. Much of the lack of top-end speed that athletes could have is due to biomechanical weaknesses as much as it is fiber types, insertions, or muscle lengths, pennation angles, and pliabilities (or insert other genetic speed determinant here).

Good sprint biomechanics are a result, largely, of strength and function in specific muscles. Very few coaches think about the fact that prime movers can become weak through the developmental stages of athletic development, or even in the advanced stages (although to a lower degree). Sprinting fast takes strength and timing of a few key muscle groups and their related movements:

Glute driven hip extension
Psoas driven knee flexion
Strong and well-functioning hamstrings that can tuck the heel tight to the buttocks in swing phase (often overlooked)

You can easily tell athletes who are deficient in these qualities. A track and field runner specializing in the 5k or 10k races has a stride that is often devoid of psoas driven knee lift (unless they are Kenyan!). In the swing phase, the foot will come up through force from the hamstring and calf, and then is rammed down back to the ground from the rectus femoris firing in the swing through. Their lack of top-end speed (although they are fantastic at maintaining the speed they have), is largely an issue of the mechanics they have created logging miles in addition to their slower muscle fiber composition.

The need for powerful glutes and hip flexors is well known. Nothing new here. The glutes and psoas must be able to fire both quickies, and with power in order to reach a high running velocity. This is true for both acceleration and top speed. There is another quality, however, that caters a bit more specifically to top-end speed, and the ability to go up and out in a jump. Hamstring strength and power in the swing-phase.

Something I had never considered until a few months ago was the role of the hamstrings in sprint heel recovery (the heel recovery in sprinting should be high, coming through over the knee, and close to the butt)

Reading Charlie Francis, I always thought quadricep flexibility was more of a limiter, as he has mentioned flexibility here as a problem for athletes with weak heel recovery. Ever since I delved deeper into the world of Bret Contreras’s articles and research musings, I became familiar with the fact that the hamstrings role in sprinting is more related to the swing phase, rather than pushing the ground down and away. Pushing the ground is more the role of the glute.

In order to sprint fast, one must be able to draw the heel close to the butt as the leg is coming through. Check out the picture below for a good example of how the knee should optimally pass over the knee (a frame taken from a high knee sprint drill). This is a 10.30-second 100m runner, and most athletes with significant top-end speed will exhibit this type of mechanic.

The strength specific to this action is found in the hamstring, and without it, all the yelling and cueing in the world won’t change a thing. Weakness in the hamstring brings about tightness in the quad. Fix the hamstring, and the situation should resolve itself. The position that the leg is brought up and through is typically with the tibia in a small amount of external rotation, which is not often considered in much strength training and testing.

This specific strength is a reason why I, personally, high jumped with a very straight swing leg (like I was kicking a soccer ball), and had trouble keeping my hamstrings healthy running hurdles (I couldn’t keep my heel tight to my butt in the swing through, and overloaded my hamstring regularly). It also explains largely why I couldn’t convert my speed up and out, in addition to just not being that fast at my top end speed.

Now that we have an idea of the qualities of these jump mechanics, let’s talk about how to train them.

Training implications: Jumping up

The great thing about jumping up off of one leg is that it is more open to the broad spectrum of the genetic lottery than jumping out. Athletes with a less than spectacular arrangement of fast twitch fibers can still be great at jumping high off one leg, as much of the proficiency here is based off of skill and muscular timing that is acquired through practice.

In order to jump up off one leg, athletes should be proficient in a few key skills that, when compounded, really help that pop upwards off of a single leg. These are namely:

Single leg strength and stability
Be able to bound
Be able to straight leg bound with the right technique
Do a variety of depth jumps, both strength and speed-oriented
Be able to do a variety of plyometrics with an efficient and quiet technique
Have good acceleration (0-20m), and decent top-end speed.
General posterior chain strength (be able to do a deadlift or sumo deadlift with good technique)
Solid feet (in addition to plyometric ability, some form of foot and ankle strength work).
Have some strength in the range you are working, namely the ½ squat range. Deep squats aren’t quite as beneficial for this specific skill, but they are good for being a well-rounded jumper.

If you are looking for more information on specific single leg jump mechanics, and training implications, along with sample programming, check out Vertical Foundations, the most complete, modern guide to jump mechanics and training implications.

Training implications: Jumping up and out

This skill is largely the same as jumping up, and then in addition:

Great top-end speed. Flying 10m speed is big here.
Strength in key top-end speed positions: hamstring strength in heel recovery, glute punch in push-off, hip flexors in knee recovery, and to counter glute punch.
Premium on short elastic contacts, and plyometric strength in the sub .16-.20 contact range.
Premium on relaxation of the upper body for improved efficiency of high-speed movements.
Premium on the mechanics of the second and third to last steps in the jump (It’s harder to paint over poor biomechanics with strength at high velocity.)

In a nutshell, to jump up well, train single leg strength through pistols and step-ups, some basic posterior chain strength and explosiveness, as well as strength in the half squat range (and some deep squat work). Work on a variety of vertical plyometrics, bounding, train speed, and elasticity hard, and most importantly, practice, practice, practice.

To jump out, get that top-end speed up through a proper speed program. In addition, make sure those glutes are firing on all cylinders through a variety of specific training means and don’t neglect the hip flexors and action of the hamstring in the swing through.

Strength exercises alone won’t always correct this completely, and personally, I’ve found a lot of magic in Douglas Heel’s BeActivated routines, as well as some things I’ve picked up from Muscle Activation Technique isometric corrections. When the phasic muscles of the body go weak (which they are prone to do), tonic, postural muscles fill in but never do as good of a job as the originals. Correcting the “muscle circuit” can bring fast improvements in speed and function.

Conclusion:

This article covers some topics that are of interest to those interested in expanding their jumping ability from up to out (or perhaps vice versa). Jumping up and out well may seem like a difficult task to many, but with practice and direction, it can be improved.