Power Testing: Drop Jump Test

The Drop Jump Test assesses reactive strength by measuring how quickly and powerfully a client rebounds after dropping from a box. It is useful for plyometric readiness and monitoring stretch-shortening cycle performance.

Introduction

An athlete may jump high, but reactive sport movement often depends on how quickly they can absorb force and rebound. The Drop Jump Test assesses this rapid braking and re-acceleration ability.

Quick Summary

Test name: Drop Jump Test
Purpose: Assess reactive strength and plyometric ability
What it assesses: Jump height, ground contact time, RSI and landing strategy
Equipment: Box, force plate/contact mat/jump system
Key finding: Reactive strength index where available
Best used with: Vertical Jump, Drop Hop, Single Leg Rebound and strength tests
Key limitation: Requires safe landing and appropriate plyometric readiness

What Is the Drop Jump Test?

The MAT page identifies Drop Jump as a Power Testing assessment.   In standard use, the client steps off a box, lands, and immediately jumps vertically as high as possible with minimal ground contact time.

Why It Is Used

It assesses reactive strength, stretch-shortening cycle efficiency and plyometric performance.

What It Measures

It may measure jump height, contact time, flight time and RSI. RSI is commonly calculated as jump height divided by contact time.

Who It Is Useful For

Athletes, jump-sport clients, field sport athletes and rehabilitation clients with adequate strength and landing tolerance.

Equipment Required

Plyometric box
Force plate, contact mat or jump system
Flat surface
Measurz or MAT
Optional video

Step-by-Step Protocol

Select an appropriate box height.

The client stands on the box.

They step off, not jump up or out.

On landing, they rebound upward as quickly and high as possible.

Record jump height and contact time where available.

Repeat for several trials with full rest.

Record best or average result consistently.

Scoring and Interpretation

Key outputs may include jump height, contact time and RSI. Higher RSI may indicate better reactive strength, but only when movement quality and landing strategy are appropriate.

Normative Data or Reference Values

No universal values should be used without matching population, box height and equipment.

Reliability and Validity

Reliability depends heavily on box height, equipment, landing instructions, arm use and athlete familiarity.

Common Errors and Testing Limitations

Common errors include jumping off the box, excessive knee bend, long ground contact, unsafe landing and changing box height.

Practical Applications

Use Drop Jump testing to monitor plyometric ability, readiness for reactive training and response to power programs.

How to Record This in Measurz

Record box height, jump height, contact time, RSI, arm use, pain, landing quality, fatigue and trial notes.

FAQs

What does the Drop Jump Test measure?

Reactive strength and plyometric rebound ability.

What is RSI?

Reactive Strength Index, commonly jump height divided by ground contact time.

Is it suitable for everyone?

No. It requires adequate landing capacity and plyometric readiness.

Key Takeaways

Drop Jump testing assesses reactive strength.
Box height and equipment must be standardised.
Record contact time and jump height where possible.
Prioritise safe landing mechanics.

References

Flanagan, E. P., & Comyns, T. M. (2008). The use of contact time and the reactive strength index to optimise fast stretch-shortening cycle training. Strength and Conditioning Journal, 30(5), 32–38.

Healy, R., Kenny, I. C., & Harrison, A. J. (2018). Assessing reactive strength measures in jump testing. Journal of Human Kinetics, 64, 203–213.