Step One: Find the peak
Finding the peak first anchors your entire analysis—it defines both the magnitude and timing of force, which everything else builds from.
In one of my previous articles, “Deconstructing a CMJ Graph,” I listed identifying the peak as the first step when analyzing a CMJ force-time trace. That’s intentional—finding the peak sets the stage for everything that follows.
There are two key aspects of the peak that give us meaningful insight:
How high is it?
Where does it happen?
Number One: How high is it?
This isn’t the end-all-be-all for determining how strong or powerful an athlete is, but peak force during a CMJ gives us a valuable snapshot of the level of force an athlete can produce in a dynamic environment.
A CMJ isn’t a sprint, cut, pitch, or swing—but all of those movements share elements of propulsion. From a vertical ground reaction force standpoint, there are clear similarities. So while it’s not a direct transfer, peak force gives us a sense of what an athlete could produce in those tasks when everything lines up.
Number Two: Where does it happen?
Producing high force is a great starting point. But if that force is produced at the wrong time—or too late to contribute to the movement—how useful is it?
Not very.
When I look at where the peak occurs, I want to understand:
Is the force profile unimodal or bimodal?
Does peak force occur near minimum displacement?
Is it the first or second peak in the trace?
This helps build an initial picture of an athlete’s strategy—how they produce force, not just how much.
From there, the analysis has to become individualized. The goal is to understand what the athlete does well, where they fall short, and how that relates to their sport.
Some of the questions I use to guide that process (which I’ll break down in future posts):
What are the demands of their sport?
Does their available range of motion align with how they execute the jump (and vice versa)?
Do time-based metrics matter for them? If so, are they a limiting factor?
From there, I typically select 2–3 key metrics specific to that athlete and track them over time. Those metrics should directly reflect the qualities they need to improve—not just what’s easy to measure.