Depth jumps are one of the most powerful plyometric exercises available for developing explosive athletic performance. They are also one of the most commonly misunderstood and most commonly performed incorrectly. Used well, they develop the reactive strength that underpins sprint speed, jumping ability, and athletic power in a way that no other exercise fully replicates. Used poorly, they load the joints beyond the athlete’s capacity to handle the demand and produce injury rather than adaptation.
This guide covers what depth jumps are, the science behind why they work, how to perform them correctly, and how to programme them for different sports and fitness levels.
What Depth Jumps Are
A depth jump is a plyometric exercise where the athlete steps off an elevated surface (typically a box of 30 to 75 centimetres), contacts the ground, and immediately jumps upward or forward with maximum force. The defining characteristic of a depth jump, which distinguishes it from a box jump or a drop jump, is the intent to minimise ground contact time while maximising the height or distance of the subsequent jump.
How depth jumps differ from similar exercises:
Box jump: The athlete jumps onto a box from the ground. The primary training stimulus is the concentric (muscle-shortening) jump phase. Ground contact is not a variable.
Drop jump: The athlete drops from a box and jumps. The focus is on the landing mechanics and the jump, similar to a depth jump but typically with less emphasis on minimising contact time.
Depth jump: The athlete steps off a box and jumps, with the specific goal of minimising ground contact time while maximising jump performance. The emphasis on brief, reactive ground contact is what makes depth jumps specifically develop the stretch-shortening cycle and reactive strength.
The Science Behind Depth Jumps
Depth jumps work through a specific physiological mechanism called the stretch-shortening cycle (SSC). Understanding this mechanism explains why depth jumps produce adaptations that other exercises cannot replicate.
The stretch-shortening cycle:
The SSC is the sequence of muscle actions that occurs when a muscle is rapidly stretched (eccentric phase) immediately followed by a rapid shortening (concentric phase). The pre-stretch of the eccentric phase stores elastic energy in the tendons and potentiates the subsequent concentric contraction through the stretch reflex.
The SSC is classified into two types:
- Slow SSC: Contact time greater than 250 milliseconds (squats, countermovement jumps)
- Fast SSC: Contact time less than 250 milliseconds (depth jumps, sprinting, hopping)
Depth jumps specifically train the fast SSC, the reactive component of the stretch-shortening cycle that is most relevant to sprinting, jumping, and rapid direction changes. This is the quality that cannot be trained by weight training alone or by slower plyometric exercises.
The reactive strength index:
The reactive strength index (RSI) is a measure of the quality of fast SSC performance, calculated as jump height divided by ground contact time. A higher RSI indicates better reactive strength. Depth jumps are both a training tool for improving RSI and a testing method for measuring it.
Specific adaptations of depth jump training:
- Increased tendon stiffness (particularly Achilles tendon), improving elastic energy storage and return
- Improved stretch reflex sensitivity and neural drive during the SSC
- Reduced ground contact time at a given force output
- Increased rate of force development (how quickly maximum force can be produced)
- Improved neuromuscular coordination during the landing-to-jump transition
These adaptations specifically improve sprint speed, jump height, and athletic agility in ways that slower strength and plyometric training cannot fully replicate.
How to Do Depth Jumps Correctly
Prerequisites Before Attempting Depth Jumps
Depth jumps generate significant ground reaction forces, typically 3 to 7 times bodyweight at the moment of landing. Before attempting them, an athlete should be able to:
- Squat 1.5 times bodyweight (or complete 5 single-leg squats per side with good form as a bodyweight alternative)
- Land safely from a box jump at the intended depth jump height
- Perform 30 consecutive double-leg ankle hops with minimal knee bend and consistent contact time
- Demonstrate consistent jumping and landing mechanics under moderate fatigue
Athletes who cannot meet these prerequisites are not ready for depth jumps and should develop their foundation through less demanding plyometrics (box jumps, broad jumps, pogo jumps) before progressing.
Step-by-Step Technique
Setup:
- Place a box of appropriate height beside a clear, flat, firm landing surface
- The landing area should be a firm, flat surface: rubber gym flooring, grass, or a track. Soft sand or thick mats are not appropriate as they reduce the reactive training stimulus.
- Stand on top of the box with the toes at the front edge
The step-off:
- Step off the box with one foot followed immediately by the other
- Do not jump off. Jumping off adds upward velocity at the start that increases landing impact beyond the intended load.
- The step should be a simple, controlled transfer of weight off the box edge
The landing:
- Contact the ground with the balls of both feet simultaneously
- The heels may lightly contact but the primary contact should be through the forefoot
- The knees should bend to approximately 20 to 30 degrees at contact (not deeply bent)
- The contact should be brief: the goal is to reverse direction as quickly as possible
The jump:
- Immediately upon ground contact, drive upward with maximum force
- Use the arms aggressively: swing them downward as the feet contact and drive them upward during the jump
- The jump should be vertical for standard depth jumps (forward jumps are a variation covered below)
- Aim for maximum height
Landing from the jump:
- Land softly on the balls of the feet with knees and hips absorbing the impact
- The landing from the final jump should be controlled and complete, not immediately followed by another depth jump
- Walk back to the box for the next repetition
Key Technical Cues
The amortisation phase is everything: The amortisation phase is the brief transition between landing contact and jump initiation. A shorter amortisation phase (quicker transition) indicates better reactive strength. Think of the legs as springs that compress briefly and immediately release, not as shock absorbers that gradually decelerate and then accelerate.
Minimal knee bend at landing: Deep knee bend at landing indicates the reactive strength system is insufficient for the current box height. The knee bend extends the contact time and shifts the load to the slow SSC rather than the fast SSC. Reduce the box height until the knee bend can be minimised.
Arms as amplifiers: The arm swing is not optional. Driving the arms downward and then upward dramatically increases jump height by adding momentum to the movement. Athletes who perform depth jumps without aggressive arm swing consistently jump lower than those who use the arms effectively.
Eyes up and chest tall: Maintaining an upright trunk position with the gaze directed forward rather than downward ensures the landing mechanics allow effective force transfer into the jump. Looking down rounds the trunk and reduces jump efficiency.
Box Height Selection
Box height selection is one of the most important and most mismanaged variables in depth jump training. Too low and the stimulus is insufficient to develop fast SSC. Too high and the landing forces exceed the athlete’s capacity, producing deep knee bend (reverting to slow SSC) or injury risk.
The reactive strength test for box height selection:
The optimal box height is the height at which ground contact time is minimised and jump height is maximised. This can be assessed practically:
- Perform 3 depth jumps from a 30-centimetre box and note subjective contact time and jump height
- Repeat from 45 centimetres, then 60 centimetres
- The height that produces the shortest, most explosive contact with the greatest jump height is the optimal height
General guidelines by athlete level:
Beginner (less than 6 months of plyometric training):
- Box height: 30 to 40 centimetres
- Characteristics: Some knee bend at landing, contact time 250 to 350 milliseconds
- Focus: Technique and landing mechanics before contact time
Intermediate (6 to 18 months of plyometric training):
- Box height: 40 to 55 centimetres
- Characteristics: Minimal knee bend, contact time 200 to 270 milliseconds
- Focus: Minimising contact time while maintaining jump height
Advanced (18 months or more of consistent plyometric training):
- Box height: 55 to 75 centimetres
- Characteristics: Very brief contact, contact time 150 to 220 milliseconds
- Focus: Maximising reactive strength index (jump height divided by contact time)
The critical warning about box height: Higher is not better beyond the optimal point. Research by Chu and others has found that box heights beyond the individual optimum produce longer contact times (because the athlete must deeply bend the knees to handle the greater landing force) and lower jump heights. A 30-centimetre depth jump performed with optimal reactive technique is more valuable than a 75-centimetre depth jump performed with deep knee bend and extended contact.
Depth Jump Variations
Standard depth jump (vertical):
The primary variation described above. Step off, contact, jump vertically.
Depth jump to broad jump:
Step off the box and instead of jumping vertically, jump forward as far as possible. Develops horizontal reactive power relevant to sprinting acceleration.
Lateral depth jump:
Step off the box and jump laterally to land on one leg. Develops the lateral reactive strength relevant to direction changes and court sports.
Single-leg depth jump:
Step off on one leg and jump from a single-leg contact. Significantly more demanding than the bilateral version and appropriate only for advanced athletes with excellent landing mechanics. Develops the unilateral reactive strength relevant to single-leg athletic actions.
Depth jump to sprint:
Step off the box, contact the ground, and immediately accelerate into a maximal sprint. Develops the transition from reactive landing to explosive acceleration, which is highly specific to the starting mechanics of sprinting.
Continuous depth jump (reactive hop landing):
After the jump, land and immediately perform another depth jump contact without a pause. Creates a continuous reactive jumping sequence. Very demanding and appropriate only for advanced athletes.
Programming Depth Jumps
Volume guidelines:
Depth jump volume is measured in contacts (each individual foot contact with the ground counts as one contact). The following guidelines reflect best practices in plyometric periodisation:
- Beginner: 40 to 60 contacts per session
- Intermediate: 60 to 80 contacts per session
- Advanced: 80 to 120 contacts per session
Total weekly contacts including all plyometric exercises should not exceed 120 to 150 for beginners, 150 to 200 for intermediate, and 200 to 300 for advanced athletes.
Frequency:
Depth jumps should be performed 2 to 3 times per week during a focused plyometric development phase. Adequate recovery between sessions (48 to 72 hours) is essential for the neuromuscular adaptations to consolidate.
Sets and reps:
- 3 to 5 sets of 4 to 8 repetitions per set
- Rest 2 to 3 minutes between sets
- Quality declines rapidly with fatigue in depth jumps. Stop the set when contact time noticeably increases or jump height decreases.
When in the session:
Depth jumps should always be performed at the beginning of the training session, after a thorough warm-up but before any fatiguing strength or conditioning work. The neuromuscular demands of depth jumps are incompatible with pre-existing significant fatigue.
Periodisation:
Depth jumps should be concentrated in dedicated plyometric development blocks of 4 to 8 weeks rather than included year-round. Following a development block, maintain reactive strength with 1 to 2 sessions per week of lower volume during the competition phase.
Sample 6-week depth jump programme:
Week 1: 3 sets x 5 reps (30cm box), 2 sessions per week
Week 2: 3 sets x 6 reps (30 to 40cm box), 2 sessions per week
Week 3: 4 sets x 5 reps (40cm box), 2 sessions per week
Week 4: 3 sets x 4 reps (40 to 50cm box), 2 sessions per week (reduced volume for adaptation)
Week 5: 4 sets x 6 reps (50cm box), 2 sessions per week
Week 6: 5 sets x 5 reps (50 to 60cm box), 2 sessions per week
Sport-Specific Applications
Sprinting and track and field:
Depth jumps develop the ground contact time and reactive strength that directly improve sprint mechanics. Incorporate depth jump to sprint variations to develop the specific transition from reactive landing to explosive acceleration. Programme 2 sessions per week during pre-season.
Basketball and volleyball:
Jump height is the primary performance quality. Standard vertical depth jumps with emphasis on maximum jump height are the most direct application. Lateral depth jumps develop the direction change ability relevant to defensive movements.
Football and rugby:
The explosive first step, sprint acceleration, and direction change qualities are all supported by depth jump training. Depth jump to sprint and lateral depth jump variations are most relevant. Programme in pre-season with maintenance during the season.
Weightlifting and CrossFit:
Depth jumps develop the explosive hip extension and reactive strength relevant to the receiving position of cleans and snatches. The barbell athlete benefits from depth jump training as an auxiliary exercise during general preparation phases.
Combat sports:
The explosive power of striking and the reactive footwork of defensive movement are both supported by depth jump reactive strength development. Single-leg variations are particularly relevant given the unilateral demands of combat sport movement.
Safety Considerations
Landing surface: Always perform depth jumps on a firm, flat surface. Soft or uneven surfaces reduce the reactive training stimulus and increase ankle instability risk.
Footwear: Wear athletic shoes with adequate lateral support. Minimalist or very flat shoes are not appropriate for depth jump training until the Achilles and calf are fully adapted to the reactive loading demands.
Progression is non-negotiable: Athletes who progress too quickly to high box heights or high volumes before the neuromuscular system is adapted consistently report patellar tendon pain, Achilles pain, and stress reactions. The progression guidelines above exist because they reflect the rate of adaptation in relevant structures.
Monitor fatigue signals: If landing mechanics deteriorate (increasing knee valgus, increasing knee bend, asymmetric landing), end the session. Continued depth jump training through technical fatigue produces poor movement patterns and injury risk.
Avoid during high training load periods: Do not introduce depth jump training during a period of very high running or sport-specific training volume. The combined load exceeds the adaptive capacity of the connective tissue and increases stress fracture risk.
Frequently Asked Questions
How are depth jumps different from box jumps?
Box jumps primarily train the concentric (muscle-shortening) power of the jump from the ground. Depth jumps specifically train the stretch-shortening cycle by using the drop from the box to create a rapid landing that must be immediately redirected into a jump. The reactive element of the landing-to-jump transition is what makes depth jumps specifically develop fast SSC qualities that box jumps do not.
What box height should I start with?
30 centimetres is the appropriate starting height for most athletes who are new to depth jumps but have a solid plyometric foundation. At this height, the landing forces are manageable while still providing a reactive training stimulus. Do not progress the height until the contact time at the current height is consistently brief and the landing mechanics are sound.
How many depth jumps should I do per session?
For beginners, 40 to 60 total contacts per session (approximately 3 sets of 5 to 6 reps from a low box). Volume should be kept low enough that the quality of every rep remains high. The moment contact time noticeably increases or jump height drops, the session should end.
Can depth jumps be done every day?
No. The neuromuscular and connective tissue recovery from depth jumps requires 48 to 72 hours. Performing depth jumps daily prevents the adaptations from consolidating and significantly increases injury risk. Two to three sessions per week during a focused development phase is the appropriate frequency.
Will depth jumps make me jump higher?
Yes, when programmed correctly. Research consistently shows that 6 to 8 weeks of depth jump training improves vertical jump height by 3 to 8 percent in trained athletes. The improvement comes from increased reactive strength, tendon stiffness, and neuromuscular coordination, which allow a more explosive and efficient stretch-shortening cycle during the jump.