Software & Technology
CMJ (Countermovement Jump)
The countermovement jump is a vertical jump performed from a standing position where the athlete dips into a quarter squat before jumping. It is the most widely used jump assessment in sport performance because it is simple to administer, highly repeatable, and sensitive enough to detect meaningful changes in neuromuscular readiness over time. When measured on a force plate, it becomes one of the most data-rich assessments available to S&C coaches.
What it measures
Jump height is the most commonly reported output, but on a force plate the CMJ captures far more: peak force, rate of force development, impulse, eccentric deceleration, concentric peak power, and landing mechanics. These variables together give a picture of how the neuromuscular system is functioning on a given day — not just how high an athlete can jump. Changes in CMJ metrics over time or across training blocks are used to assess fatigue, track adaptations, and inform load management decisions.
How coaches use it
Many programs now use CMJ as a regular monitoring tool, not just a testing event. A weekly or bi-weekly CMJ gives the coaching staff a reference point for where each athlete’s neuromuscular system is relative to their baseline. Drop in jump height combined with changes in force-time curve shape can flag accumulated fatigue before it becomes a performance or injury problem. The test takes under two minutes per athlete and requires only a force plate or, at lower resolution, a jump mat or smartphone app.
Related terms
Force Plate · RFD (Rate of Force Development) · Readiness Score · Force-Velocity Profiling