The Stretch Shortening Cycle for a Plyometric Boost

The average male is capable of jumping straight up in the air about 16-20 inches. A really good jumper — at the park — might average about 28 inches. What does a Zion Williamson stretch shortening cycle look and feel like? According to Duke coach Mike Krzyzewski, its helps pop a whopping 45 inches on the old vertical! But you’ll need to ask one of Zion’s posterized opponents what it feels like.

Consider, if you will, the curious phenomenon of the Stretch Shortening Cycle (SSC) — a term so esoteric and brimming with scientific undertones that it almost begs for the layperson to glaze over it. But, much like the seemingly mundane act of boiling water which, upon closer inspection, reveals a tumultuous dance of H2O molecules, the SSC is a hidden gem of muscular wonderment¹.

Now, plyometrics, from the Greek “plio” (more) and “metric” (length), is a kind of exercise involving a sort of ballistic burst. Imagine, say, a frog leaping suddenly from one lily pad to another. For us humans, it’s the difference between a casual stroll in the park and a spirited hop over a puddle that you didn’t quite gauge the size of correctly².

At the heart of this leap is our dear SSC. When a muscle is rapidly stretched (the eccentric phase), it’s like you’re pulling back on a slingshot. Release it (the concentric phase), and — voila! — you’ve got an extra oomph in your motion. The muscle, in its pre-stretched state, harnesses more energy, more potential, like a coiled spring or a student waiting anxiously for the bell to signal the end of a particularly tedious lecture³.

The real magic, however, is in the transition. The shorter the pause between the stretch and the release, the greater the resultant force. This is the SSC’s pièce de résistance. It’s a game of milliseconds, a brief moment where the body’s mechanical energy is transformed into a powerful, explosive motion.

Vertical Jump Records are Meant to be Broken

Zion was one and done with great reason. But now Duke Freshmen Cassius Stanley takes vertical leaping to even greater heights — literally. How high can he jump? 46.5 inches of explosive, rim-rattling leaping ability.

How does someone jump that high? Do you have to be born with it? Must you be on the Duke Basketball Team?

While a little natural talent does help, there are exercises you can do to strengthen the muscles needed to reach new heights. 

What Is the Stretch Shortening Cycle

Try to jump straight up in the air from a standstill. Likely you did a little squat first to gather power for your upward travels. Maybe even a couple steps or a little hop beforehand. The key is you were never at a complete standstill.

This is called a “countermovement” and is why this type of jump is called a countermovement jump or CMJ.

You can think of this movement like a coiled spring, exerting a bit of energy downward gives the body the ability to explosively spring back in the opposite direction. Through this action, most people can jump 2-4 centimeters higher than when jumping from a static squat with no countermovement. 

Three phases make up the stretch shortening cycle — eccentric, isometric, and concentric contractions. Think of eccentric contraction like lengthening a rubber band, the isometric phase is a transitional period right before the rubber band snaps or is released, and the concentric contraction is the resulting explosive movement when the rubber band flies from your fingers.

Plyometric Exercises 

You can strengthen this cycle with an assortment of plyometric exercises. While still remaining focused on training individual aspects of the stretch shortening cycle to find your personal Zion Williamson vertical limits.

To do so challenge yourself with a number of different exercises, but when working specifics consider the below when adding plyometrics into any workout.

• Eccentric movements: Like running and jumping in sand. Focus on your lengthening and keep your knees, hips and chest in line to avoid injury
• Isometric: Control the explosive energy without snapping the ‘rubber band’ — hold landings for a full 2 seconds before completing a movement
• Concentric: Ground reaction forces. Focus on the explosion and drive into the direction the energy needs to travel — train fast!

A Word of Caution

Particularly when training the eccentric phase, be aware of Delayed Onset Muscle Soreness (DOMS). Tensing the muscle at the same time that you lengthen it, as happens in the eccentric movement, can more readily cause microscopic tearing in the muscles.

Symptoms, which include short-term muscle weakness, pain, and swelling, appear 12-24 hours after your workout. Keep moving to work out the soreness and massage the muscles. Use varying temperatures to ameliorate the pain and anti-inflammatory foods can also help recovery.

Find New Vertical Limits

Try adding some plyometric exercises to your workout routine. Even if you can’t quite make a Zion Williamson vertical leap, you just might throwdown during your next pickup game.

So, the next time you find yourself bounding up a set of stairs two at a time, or jumping over that deceivingly large puddle, take a moment — a brief one, mind you — to marvel at the intricacies of the human body, that grand symphony of coordinated chaos, playing its tune of motion and might