Loaded Jump Test: how to measure power under resistance

So far we've covered jump tests with bodyweight only. But what happens when we add external resistance, like a Squat Jump with a barbell? The Loaded Jump Test introduces that variable, and it's the gateway to one of the most powerful concepts in strength-power assessment: how an athlete's power output changes as load increases.

What does this test measure?

It assesses the power produced in a vertical jump (typically a Squat Jump) under different external loads, allowing you to identify the load at which the athlete produces their maximum power (the optimal load). It's the basis for building an individualized load-power profile.

Equipment needed

• Olympic barbell with plates, Smith machine, or weighted vest
• Force plate or linear position transducer (needed to measure power accurately; without these devices you can only measure jump height, which is less informative at higher loads)
• Safe space for jumping with load

Test protocol

1. The subject sets up with the chosen load (barbell on the traps or a weighted vest), in a semi-squat position similar to the Squat Jump
2. Tell them to perform a maximum vertical jump while keeping the load throughout the movement (the barbell isn't released; the vest stays attached to the body)
3. The linear transducer or force plate records the velocity and/or jump height with that load
4. Repeat the process with different progressive loads (e.g., bodyweight, 10%, 20%, 30%, 40% of bodyweight added)
5. Record the power (or jump height) obtained at each load
6. Identify the load that produces the highest absolute power

Common mistakes

• Using only bodyweight, losing the information about how power changes with load (that would just be a regular Squat Jump)
• Not using a velocity/power measurement device, relying only on jump height, which becomes less informative at moderate-to-high loads
• Increasing the load too quickly without specific progressive warm-up
• Not keeping the same execution technique (depth, descent speed) across different loads

How to interpret the result

Interpretation isn't based on a single value but on the shape of the power-load curve:

Pattern observed	Interpretation
Power peaks at light loads (0-20% bodyweight)	Speed-oriented profile, may benefit from maximal strength work
Power peaks at moderate loads (20-40%)	Balanced profile
Power peaks at higher loads (>40%)	Strength-oriented profile, may benefit from speed/plyometric work

The training goal is usually to shift the curve upward across its whole range, not just at one point.

Relationship with other tests

This test is the natural step toward a more complete strength profile assessment:

• Force-Velocity Profile — extends this concept into a full mathematical analysis of the force-velocity-power relationship
• Squat Jump Test — the unloaded version, and the starting point of this progression

Track and monitor

Building a load-power profile means logging several data points (load and result) in an organized way — something that gets messy fast on paper. With Movalytics you can record the power or height obtained at each load during the same assessment, and compare how your athlete's full curve evolves from one training block to the next, not just an isolated value.

Frequently asked questions

Do I need a linear transducer? For accurate power analysis, yes, it's highly recommended. Without one, you can still use jump height at each load as an approximation, though it loses precision at higher loads. What loads should I test? A common range is from bodyweight up to roughly 40-50% of bodyweight added, in 10% increments, though this can be adjusted based on the athlete's level and goals. Is it a safe test? With proper technique and progressive loads, yes — but the athlete should already have solid unloaded Squat Jump technique before adding external resistance.