Plyometrics for Teens

Springs in your legs

Have you ever noticed how a ball bounces higher if it is dropped harder? Your muscles have a similar springiness. Plyometrics are exercises, mostly jumps, hops and bounds, that train your body to use that natural spring to produce explosive power. Done well, they make you jump higher, change direction faster, and feel more athletic.

This lesson explains the science behind plyometrics, how to do them safely, and why landing well comes before jumping high. It builds on the idea of producing force quickly, so it pairs well with The Science of Speed and Strength.

What plyometrics are

Plyometrics are fast, powerful movements where a muscle is quickly stretched and then immediately contracts. Examples include:

• Jumping and landing.
• Hopping on one or two legs.
• Bounding (big, springy running strides).
• Skipping for height.

The defining feature is speed: the contact with the ground is brief and explosive. This is different from slow strength training. Plyometrics train the body to be springy and reactive.

The stretch-shorten cycle

The secret behind plyometrics is the stretch-shorten cycle. Your muscles and tendons behave a little like elastic bands.

When you land from a jump or dip down before leaping, your muscles are quickly stretched under load. This stores elastic energy in the muscles and tendons, like stretching a rubber band. If you then immediately push off, that stored energy is released, adding to the force your muscles produce. The result is a more powerful movement than muscle contraction alone could create.

The key word is immediately. The energy is only useful if the switch from landing to launching happens fast. Pause too long and the stored energy leaks away as heat. That is why plyometrics emphasise quick, reactive ground contacts.

Landing comes first

Here is the rule every good coach insists on: learn to land before you learn to jump high. Every jump ends in a landing, and landings create large forces through your ankles, knees and hips. Landing stiffly or off-balance is where injuries happen.

A good landing is:

• Soft: bend at the ankles, knees and hips to absorb force, like a quiet, cushioned touchdown.
• Quiet: if you hear a loud thud, you are landing too hard.
• Balanced: knees tracking over the toes (not collapsing inward), body controlled.

A great first exercise is the jump and stick: do a small jump and land softly, then "stick" the landing, holding it steady for a second. Master that before adding height or speed.

Safe progressions to try

Build up in this order, only moving on when the previous step feels easy and controlled:

1. Jump and stick: small two-footed jumps, landing softly and holding.
2. Pogo hops: small, quick, springy hops on the spot, staying light and bouncy.
3. Low broad jumps: jump forward a short distance, land softly and stick it.
4. Skipping for height and gentle bounding once landings are solid.
5. Low box step-downs, stepping off a low box and landing softly, before any box jumps.

Keep boxes and jumps low at first. Higher is not better for beginners, it just increases landing forces.

Keeping plyometrics safe

Plyometrics are powerful but demanding, so follow these rules:

1. Warm up thoroughly with easy movement and dynamic drills, see Dynamic Warm-Ups by Sport.
2. Master landings first, soft, quiet and balanced.
3. Start low and simple, progressing only when controlled.
4. Keep the volume low. A small number of quality jumps beats many tired ones. Count your jumps and stop while still sharp.
5. Take full recovery between efforts so each is explosive.
6. Use a forgiving surface (grass or a sprung floor), good footwear, and never jump when fatigued.
7. Progress gradually over weeks and train under a coach, see Preventing Sports Injuries.

Quick recap

• Plyometrics are fast, springy jumps and hops that build explosive power.
• They work through the stretch-shorten cycle: muscles store elastic energy when stretched, then release it.
• The energy only helps if landing-to-launch happens immediately.
• Soft, quiet, balanced landings must be learned before jumping high.
• Start low, simple and low-volume, with full recovery, a good warm-up, gradual progress and coaching.

Treat plyometrics with respect and they can unlock real athletic spring, safely.