Last year was a tough one for achieving our fitness goals. Between gyms being shut and ‘home gym equipment’ getting typed into search bars more than ever – there were some unique and challenging circumstances making hitting those goals quite hard to do.

For some of us, we patiently waited for gyms to re-open. For others, we worked out with what had around home and for the lucky-ones that snatched up weights from Facebook Marketplace (looking at you “pending pick-up” person!) some people were able to put together some great home-gym set-ups and continue to get fitter faster and stronger.

With 2020 now firmly in the rear-view mirror let us grip that steering wheel, shift it up a gear and come jump-in with me into your complete guide to the science of jumping high in 2021.

When thinking of jumping in a high-performance sense we often picture the likes of Michael Jordan gracefully floating through the air and dunking the basketball or perhaps Olympic Volley-Ball players springing out of the sand and above the net spike a ball – but how do we measure jumping? How do we train to jump higher and are all jumps the same?

Box Jumps

If you see someone jumping in the gym, they are typically either doing burpees or performing what is commonly referred to as a ‘box-jump’ which are typically performed on plyometric boxes with standard dimensions of 20”x24”x30”.

Pictured: Some guy with the same initials and birthday as me, wearing green, doing a box-jump.

Image credit: Yours truly.

There are 3 key parts to performing a box-jump:

The countermovement – this is what you do leading into your jump. Swinging your arms back, flexing your hips, knees then ankles like springs that are ready uncoil fast.
The jump itself – Now that the springs are loaded your muscles will need to contract fast and hard in order to get you off the ground. The faster you transition from the countermovement and the more force your muscles can produce against the ground -the higher you are able to jump!
The landing: This is where it gets interesting. In 2016 Evan Ungar pictured below set the box jump world record at 63.5 inches (that is the equivalent of over 3 plyometric boxes stacked on their sides!)

Pictured: Evan Ungar working on his world record box jump.
Image credit: https://www.wired.com/story/ai-vertical-leap/

Now you may notice a difference between the first and second picture. The first being that my knees are starting to rise above my hip height, indicating that this was at the end of where the vertical acceleration was taking me, and the rest was becoming a ‘tuck’. Tricky right? In the second picture we can see that Evan is fully tucked – I can certainly not jump as high as he can, but it kind of shows that a box jump is not really a true test of vertical jump height, because once your hips stop going up, it really becomes a measure of who can tuck their legs in more!

So, if watching someone jump onto a wooden box does not give us the clearest picture – what can scientific equipment do for us? Before jumping into the scientific tools to measure jumping performance, let us look at the science of the jump itself.

During the “squatting” or “hinging” phase of a jump the prime mover and synergist muscles of the jump lengthen. During the jump itself, they shorten. This is referred to as a stretch-shortening-cycle (SSC).

The stretch-shortening cycle (SSC) refers to the muscle action when active muscle lengthening is immediately followed by active muscle shortening.

This combination of eccentric and concentric contractions is one the most common type of muscle action during locomotion. Image credit:

https://www.frontiersin.org/image/researchtopic/10437

Force Plates

“Force plates are mechanical sensing systems designed to measure the ground reaction forces and moments involved in human movements. A force plate relies on the use of load cells to determine forces.”
When you jump on a force plate, each phase of your jump sends valuable information to the load cells, which are then computed and graphed out to show just how good or bad your jump is.

The eccentric component:This is where you have swung your arms back, bent your hips, knees and ankles.
The amortization component: This is where your muscle transitions from overcoming the acceleration of gravity and loading the energy to releasing it – the key here is if this segment takes too long the potential elastic energy is lost.
Concentric component: Unloading the elastic energy occurs here, adding tension to the concentric muscle contraction. This where you release the stored and re-directed energy, jumping to the sky.

Pictured: Athlete using force plate to assess jumping performance.
Image credit: https://simplifaster.com/articles/force-velocity-profiling/

How bad jumpers’results look on a force plate reading, according to Jacob Tober from Core Advantage (One of Melbourne’s premier athletic development centres)

Long build up in eccentric phase for minimal output.

(Image credit https://coreadvantage.com.au/blog/2017/the-science-of-vertical-jumping)

How good jumpers’ results look on the force plate:

Faster loading, turnaround time; more powerful jumping.

(Image credit https://coreadvantage.com.au/blog/2017/the-science-of-vertical-jumping)

Key take-aways and challenges

In order to jump high we need to stretch strongly, then quickly switch from that stretched position to a strong and forceful shortening of our muscles.

Box jumps do provide some value in assessing jumping performance; however, we must be mindful of the specificity of the testing here – are we testing true jump height, or a combination of jumping and tucking? If we want to most accurately assess jumping, we need to measure more than whether the dart has hit the board. We need to gauge whether we have hit a bullseye or not!

Unfortunately, there is a price to pay for the luxury of having a force-plates level of specificity and sensitivity. The price being thousands of dollars out of the average trainers pocket.

Expert advice

Presented with the problem of trainers wanting to test specifically and accurately yet also not wanting to spend thousands of dollars, I asked Dr Luke Del Vecchio – one of Australia’s most credentialed sports scientists to see if there are better options for trainers who want accurate testing technology, minus the big bill. Knowing that Dr Luke is a leader in both martial arts and combat sports research and is devoted to the enhancement of human athletic performance, I trusted that he would be able to assist with our predicament. Here is what he had to say:

“Hi Ben, given APP/wearable technology is almost as reliable as a force plate, I would suggest Fitness Trainers familiarise themselves with apps such as “myJump” which can be used to diagnose jumping performance such as “Eccentric Utilisation Ratio”. Put simply, clients should be able to jump at least 10% higher on a countermovement (hinge) jump than squat jump. Anything less than this suggests the client has not developed their SSC (stretch shortening cycle) potential and that they generate most of their jumping force from the contractile force in the muscles”.

My thoughts/conclusion

Woah. A lot to unpack there. So, there are now apps for your phone at a fraction of the cost of laboratory testing equipment, and yet they still provide the type relevant scientific data that we need to assess, interpret and prescribe exercise from.Dr Luke also highlighted that science is now starting to reveal that your hinge-jump to squat-jump performance ratio is key in unlocking maximal jumping height. Given the hinge jump has a larger countermovement and really taps into the stretch shortening cycle, this is golden information for the assessing and planning of our jumping programs.

There are plenty of great exercises out there to help you work that stretch-shortening cycle and increase your jump in 2021.Given the expert advice from Dr Luke Del Vecchio, I would suggest that you consider incorporating these 3 countermovement style exercises into your routine:

1) Kettlebell hinge swings
2) Power bag shouldering
3) Dumbbell pendulum swings.

The three exercises listed above will help bring up that hinge strength, assisting you in bridging the gap between your squat and swing jump and hopefully propelling you to further heights in 2021.

Happy swinging and jumping!

Written by Ben Gunn,

Educator for the Functional Training Institute.

References:

Subscribe To Our Newsletter

For for Newsletter