What are plyometrics?
Plyometrics are exercises that use a rapid stretch-shortening cycle, where a muscle lengthens under load then immediately shortens, to produce more force than a slow movement could. Jumps, hops, bounds, and throws are the common examples.
How they work
When a muscle-tendon unit is stretched quickly and then shortens straight away, two things help. Elastic energy stored in the tendon during the stretch is returned during the shortening phase, and reflexive muscle activity increases the force produced. Both depend on the transition being fast. Pause at the bottom of a jump and the elastic contribution disappears, which is precisely why plyometrics are defined by their speed rather than by looking energetic.
The main categories
- Jumps: Two-foot takeoff and landing, such as countermovement jumps and box jumps.
- Hops: Same-leg takeoff and landing, such as pogo hops.
- Bounds: Alternating legs with horizontal travel, such as bounding and skater bounds.
- Shock methods: Depth jumps and drops, which are the most demanding and should come last.
- Upper body: Medicine ball throws and clap push-ups.
Why they are worth training
Sprinting, cutting, jumping, and throwing all depend on producing force in very short ground contact or arm-acceleration times. Heavy strength training alone does not fully develop that quality, which is why explosive and reactive work sits alongside it rather than instead of it.
Programming basics
Keep volume modest, in the region of 20 to 60 contacts per session for most people. Do it while fresh, at the start of a session. Rest fully between sets so every effort is maximal. Progress from low-intensity hops to higher-intensity jumps over weeks, not within a session.
Prerequisites
Be able to control your bodyweight in a squat, land quietly from a small hop, and train without current lower-limb pain before starting. The full progression is set out in Introduction to Plyometrics and the mechanism in The Stretch-Shortening Cycle.
