Power · 3 min read
A countermovement jump on force plates is one of the most informative tests available for how an athlete produces force. The jump height is the least interesting thing it tells you.
By Chris Gkoufas, DVOTION
The plates measure ground reaction force continuously through the whole movement — the dip down, the transition, the push, the flight and the landing. Sampling is fast enough to resolve what happens within each phase rather than only the outcome.
From that force-time record it is possible to describe not just how much force was produced, but how quickly, in what sequence, and how evenly between limbs.
Two athletes can jump the same height by different means. One may produce a large peak force over a short period. Another may produce less peak force but sustain it for longer. A third may reach the same height with a deeper, slower countermovement.
Those are different capabilities with different training implications, and jump height alone cannot separate them. That is the argument for measuring the force-time curve rather than the result.
How quickly force rises matters in any sport where the time available to produce it is limited. Ground contact in running is short. So is the transition in a change of direction.
An athlete can be strong in absolute terms and still develop force too slowly for the demands of their sport. Conversely, an athlete with modest peak force but rapid development can perform well in tasks constrained by time. Measuring both separates a strength problem from a rate problem, and they are trained differently.
The countermovement and the landing are as informative as the push. Absorbing force is a distinct capability from producing it, and it is where a good deal of the mechanical demand of running and jumping actually sits.
How an athlete organises the downward phase — how deep, how fast, how the load is distributed — shapes what happens in the phase that follows. This is one of the places where force plate findings and a movement assessment inform each other directly.
The countermovement jump is a useful monitoring test because it is quick, low-risk and repeatable. That makes it suitable for tracking across a training block, provided the same protocol is used each time.
What is worth tracking is not the whole output but two or three values relevant to your sport, chosen deliberately. Recording everything and comparing everything tends to produce noise rather than signal.
No. The countermovement jump is used as a window into how you produce and absorb force. It is informative for endurance athletes as well as for sports where jumping is part of the event.
Several, so that a representative trial can be identified rather than a single attempt that may not reflect your usual pattern.
Frequently enough to see change across a training block. Because the test is quick and low-risk, it suits more regular monitoring than a full assessment.