Linear Depth Jump
Also works: Calves · Glutes · Hamstrings
You step off one box, absorb the drop with the floor, and immediately jump forward onto a second. The fall pre-loads your legs harder than any voluntary dip can, which makes this one of the most demanding plyometrics there is — and one of the easiest to do too much of.
Own the movement
Set up first, then execute. Every cue below is something you can check on your next set.
Before the first rep
- Start with a drop box 30-40 cm high. Higher boxes lengthen ground contact, which is exactly the wrong direction.
- Place the landing platform 90-150 cm forward — close enough that you clear it without reaching, and set it no higher than the drop box.
- Check both boxes are stable and will not slide, and that the landing top is non-slip.
- Stand on the edge of the drop box with your toes at the lip, weight on the mid-foot, arms slightly behind you.
- Earn the drill first: you should be able to land a plain box jump silently in a quarter squat before you ever step off a box.
Every rep
Breathing & tempo — Inhale on the box, hold through the step-off and the contact, exhale sharply as you leave the floor. The only tempo that matters is the ground contact: target under 0.25 seconds, and if you can hear two distinct sounds down there it is too long.
Before you load it
- Do not attempt depth jumps until you can back squat around 1.5x bodyweight or land plain box jumps silently. Reactive work on unprepared tendons is where patellar tendon problems start.
- Stop the session the instant contact time visibly lengthens. Fatigued depth jumps carry the full injury risk and produce none of the adaptation.
- Skip these entirely if you have current knee, Achilles or lower back pain. There is no light version of a depth jump — the load comes from gravity, and you cannot dial it down much.
Sets, reps & load
Where to start, and what to change when it stops being hard.
Bodyweight only, no exceptions — added load lengthens ground contact and defeats the purpose. Progress in this order: shorten contact time, then push the landing platform 15 cm further away, then raise the drop box by 10 cm. Total contacts should stay under about 30 per session, and under 60 across a week including all other jumps.
What goes wrong
The errors that show up most often, and the cue that fixes each one.
Film a set from the side. If your knees dip past a quarter squat on the floor contact, lower the drop box by 10 cm and try again. Most people are best served by 30-40 cm for years.
Treat the floor as hot. Cue 'off the ground' the moment your forefoot touches; if you cannot, you are not ready for the depth jump and should be doing bench jumps instead.
Cap sets at three reps and rest two to three minutes. The moment the second contact takes longer than the first, that session's useful work is finished.
Step off with one foot and let the other join it in the air. Jumping down turns a 40 cm drop into a 60 cm one and doubles the load your knees never agreed to.
Why bother
A normal jump loads your legs with whatever force you can generate on the way down. Dropping off a box loads them with gravity instead, and the eccentric spike on landing is far higher than you could produce yourself. Your tendons store that energy, and if you reverse it fast enough you get it back. That is the whole mechanism, and it is why depth jumps improve reactive strength faster than any other bodyweight drill.
The catch is the word 'fast enough'. If your foot is on the floor for more than about a quarter of a second, the stored energy has already dissipated as heat and you are just doing a tiring jump with a hard landing. Ground contact time is the metric here, not distance covered or box height.
Where it fits
Only after several months of jump training, only fresh, and only at the front of a session — first thing after the warm-up, before squats. Three or four sets of three, two to three minutes between sets. One session a week is plenty; two is the ceiling for anyone not being coached. Never pair depth jumps with a heavy leg day in the same 48 hours if your knees have any history.
If this one isn't it
No kit, too hard, or too easy — here's where to go instead.
Same job, different kit
Asked and answered
Do I need a second box, or can I just jump straight up?
Both are legitimate and they train different directions. Dropping and jumping vertically is the classic version and the one most research uses; dropping and jumping forward onto a platform, as here, biases horizontal force and carries over better to sprinting and long jump. Pick by what you do. Do not do both in the same session — the contact budget is small and splitting it halves the quality of each.
What is the difference between this and a box jump?
A box jump starts on the floor with you choosing how hard to load your legs. A depth jump starts above the floor and lets gravity choose, which produces a much larger eccentric force and a far more demanding rebound. Box jumps are a starting point; depth jumps are an advanced tool for someone with a real strength base.
How many should I do in a session?
Around 9-12 contacts, split into three or four sets of three, with two to three minutes rest. That feels like nothing, and that is correct — the drill is measured in quality, not volume. If you finish feeling like you have had a workout, you did too many.
Can I do these on a gym floor?
Rubber gym flooring, a sprung wooden floor, or a track are all fine. Bare concrete is not — it returns force to your joints that a forgiving surface would absorb. Grass is safe but soft enough to lengthen your ground contact, which slightly blunts the effect.