Why Hop Tests Might Be Misleading in ACL Rehab

When it comes to ACL rehab, hop tests have become a go-to tool for assessing readiness to return to sport. But here’s the problem: they might not be telling you the full story.




1. Hop Tests Measure Symmetry, Not Strength

Most hop test assessments use the Limb Symmetry Index (LSI) — comparing the injured leg to the uninjured one. But what if both legs are weak? You might score well on symmetry but still lack the strength needed to return safely. This is what I call the “two flat tyres” problem. Symmetrical? Yes. Functional? Not at all.

2. Pre-Injury Scores Matter

One of the biggest gaps in ACL rehab testing is the lack of pre-injury data. Without knowing what your performance looked like before the injury, it’s hard to know how much you’ve truly recovered. A 90% LSI might still mean you’re 30% down from where you used to be.

3. Maximal Strength Is the Real Key

Your maximal strength, especially in key muscle groups like the quads and hamstrings, is a far better indicator of your readiness to return. If you can’t produce force at the levels needed for your sport, hop distance won’t save you.

4. Compare to Normative Data, Not Just Yourself

It’s not enough to compare leg to leg — you need to compare against normative standards for your sport, position, and level. For example, elite field hockey players often require 2x bodyweight strength. Are you there yet?

In Summary:
Hop tests can be a helpful tool, but they shouldn’t be the only one in your ACL rehab toolkit. Prioritise maximal strength, use pre-injury baselines, and always consider normative performance data.

Ready to get back to sport? Make sure you’re testing what truly matters.